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Sample records for acuity improved significantly

  1. Color improves "visual" acuity via sound.

    PubMed

    Levy-Tzedek, Shelly; Riemer, Dar; Amedi, Amir

    2014-01-01

    Visual-to-auditory sensory substitution devices (SSDs) convey visual information via sound, with the primary goal of making visual information accessible to blind and visually impaired individuals. We developed the EyeMusic SSD, which transforms shape, location, and color information into musical notes. We tested the "visual" acuity of 23 individuals (13 blind and 10 blindfolded sighted) on the Snellen tumbling-E test, with the EyeMusic. Participants were asked to determine the orientation of the letter "E." The test was repeated twice: in one test, the letter "E" was drawn with a single color (white), and in the other test, with two colors (red and white). In the latter case, the vertical line in the letter, when upright, was drawn in red, with the three horizontal lines drawn in white. We found no significant differences in performance between the blind and the sighted groups. We found a significant effect of the added color on the "visual" acuity. The highest acuity participants reached in the monochromatic test was 20/800, whereas with the added color, acuity doubled to 20/400. We conclude that color improves "visual" acuity via sound. PMID:25426015

  2. Defining lactation acuity to improve patient safety and outcomes.

    PubMed

    Mannel, Rebecca

    2011-05-01

    While substantial evidence exists identifying risks factors associated with premature weaning from breastfeeding, there are no previously published definitions of patient acuity in the lactation field. This article defines evidence-based levels of lactation acuity based on maternal and infant characteristics. Patient acuity, matching severity of illness to intensity of care required, is an important determinant of patient safety and outcomes. It is often used as part of a patient classification system to determine staffing needs and acceptable workloads in health care settings. As acuity increases, more resources, including more skilled clinicians, are needed to provide optimal care. Developing an evidence-based definition of lactation acuity can help to standardize terminology, more effectively distribute health care staff resources, encourage research to verify the validity and reliability of lactation acuity, and potentially improve breastfeeding initiation and duration rates. PMID:21527797

  3. Microperimetric Biofeedback Training Improved Visual Acuity after Successful Macular Hole Surgery

    PubMed Central

    Ueda-Consolvo, Tomoko; Otsuka, Mitsuya; Hayashi, Yumiko; Ishida, Masaaki; Hayashi, Atsushi

    2015-01-01

    Purpose. To evaluate the efficacy of setting a preferred retinal locus relocation target (PRT) and performing Macular Integrity Assessment (MAIA) biofeedback training in patients showing insufficient recovery of best corrected visual acuity (BCVA) despite successful closure of an idiopathic macular hole (MH). Methods. Retrospective interventional case series. Nine eyes of 9 consecutive patients with the decimal BCVA of less than 0.6 at more than 3 months after successful MH surgery were included. A PRT was chosen based on MAIA microperimetry and the patients underwent MAIA biofeedback training. BCVA, reading speed, fixation stability, and 63% bivariate contour ellipse area (BCEA) were evaluated before and after the training. Statistical analysis was carried out using paired Student's t-test. Results. PRT was chosen on the nasal side of the closed MH fovea in 8 patients. After the MAIA training, BCVA improved in all patients. The mean logMAR value of BCVA significantly improved from 0.33 to 0.12 (p = 0.007). Reading speed improved in all patients (p = 0.29), fixation stability improved in 5 patients (p = 0.70), and 63% BCEA improved in 7 patients (p = 0.21), although these improvements were not statistically significant. Conclusion. MAIA biofeedback training improved visual acuity in patients with insufficient recovery of BCVA after successful MH surgery. PMID:26783452

  4. Improvement of tactile roughness discrimination acuity correlates with perception of improved hand function in patients after hand surgery

    PubMed Central

    Fujimoto, Shuhei; Kon, Noriko

    2016-01-01

    [Purpose] The purpose of this study was to elucidate how well patients’ perceptions related to the improvements in their hand function during hospitalization. [Subjects] Sixteen patients who were hospitalized after hand surgery. [Methods] Using the Japanese Society for Surgery of the Hand edition of the Quick-Disabilities of the Arm, Shoulder, and Hand questionnaire; tactile roughness discrimination acuity, motor imagery, motor function, sensory function, and pain of the upper limb were assessed at admission and discharge. Spearman’s rank-order correlation coefficients were calculated using the differences in all assessment items at admission and discharge. A multiple regression analysis (stepwise method) was performed to investigate factors that correlated with improvements in Quick-Disabilities of the Arm, Shoulder, and Hand scores. [Results] The improvement of tactile roughness discrimination acuity was significantly associated with patient perception of improved hand function. [Conclusion] The results suggest that an improvement in tactile roughness discrimination acuity was most strongly correlated with patient perception of improved hand function. PMID:27190473

  5. Improvement of tactile roughness discrimination acuity correlates with perception of improved hand function in patients after hand surgery.

    PubMed

    Fujimoto, Shuhei; Kon, Noriko

    2016-04-01

    [Purpose] The purpose of this study was to elucidate how well patients' perceptions related to the improvements in their hand function during hospitalization. [Subjects] Sixteen patients who were hospitalized after hand surgery. [Methods] Using the Japanese Society for Surgery of the Hand edition of the Quick-Disabilities of the Arm, Shoulder, and Hand questionnaire; tactile roughness discrimination acuity, motor imagery, motor function, sensory function, and pain of the upper limb were assessed at admission and discharge. Spearman's rank-order correlation coefficients were calculated using the differences in all assessment items at admission and discharge. A multiple regression analysis (stepwise method) was performed to investigate factors that correlated with improvements in Quick-Disabilities of the Arm, Shoulder, and Hand scores. [Results] The improvement of tactile roughness discrimination acuity was significantly associated with patient perception of improved hand function. [Conclusion] The results suggest that an improvement in tactile roughness discrimination acuity was most strongly correlated with patient perception of improved hand function. PMID:27190473

  6. A double dissociation of the acuity and crowding limits to letter identification, and the promise of improved visual screening.

    PubMed

    Song, Shuang; Levi, Dennis M; Pelli, Denis G

    2014-01-01

    Here, we systematically explore the size and spacing requirements for identifying a letter among other letters. We measure acuity for flanked and unflanked letters, centrally and peripherally, in normals and amblyopes. We find that acuity, overlap masking, and crowding each demand a minimum size or spacing for readable text. Just measuring flanked and unflanked acuity is enough for our proposed model to predict the observer's threshold size and spacing for letters at any eccentricity. We also find that amblyopia in adults retains the character of the childhood condition that caused it. Amblyopia is a developmental neural deficit that can occur as a result of either strabismus or anisometropia in childhood. Peripheral viewing during childhood due to strabismus results in amblyopia that is crowding limited, like peripheral vision. Optical blur of one eye during childhood due to anisometropia without strabismus results in amblyopia that is acuity limited, like blurred vision. Furthermore, we find that the spacing:acuity ratio of flanked and unflanked acuity can distinguish strabismic amblyopia from purely anisometropic amblyopia in nearly perfect agreement with lack of stereopsis. A scatter diagram of threshold spacing versus acuity, one point per patient, for several diagnostic groups, reveals the diagnostic power of flanked acuity testing. These results and two demonstrations indicate that the sensitivity of visual screening tests can be improved by using flankers that are more tightly spaced and letter like. Finally, in concert with Strappini, Pelli, Di Pace, and Martelli (submitted), we jointly report a double dissociation between acuity and crowding. Two clinical conditions-anisometropic amblyopia and apperceptive agnosia-each selectively impair either acuity A or the spacing:acuity ratio S/A, not both. Furthermore, when we specifically estimate crowding, we find a double dissociation between acuity and crowding. Models of human object recognition will need to

  7. A double dissociation of the acuity and crowding limits to letter identification, and the promise of improved visual screening

    PubMed Central

    Song, Shuang; Levi, Dennis M.; Pelli, Denis G.

    2014-01-01

    Here, we systematically explore the size and spacing requirements for identifying a letter among other letters. We measure acuity for flanked and unflanked letters, centrally and peripherally, in normals and amblyopes. We find that acuity, overlap masking, and crowding each demand a minimum size or spacing for readable text. Just measuring flanked and unflanked acuity is enough for our proposed model to predict the observer's threshold size and spacing for letters at any eccentricity. We also find that amblyopia in adults retains the character of the childhood condition that caused it. Amblyopia is a developmental neural deficit that can occur as a result of either strabismus or anisometropia in childhood. Peripheral viewing during childhood due to strabismus results in amblyopia that is crowding limited, like peripheral vision. Optical blur of one eye during childhood due to anisometropia without strabismus results in amblyopia that is acuity limited, like blurred vision. Furthermore, we find that the spacing:acuity ratio of flanked and unflanked acuity can distinguish strabismic amblyopia from purely anisometropic amblyopia in nearly perfect agreement with lack of stereopsis. A scatter diagram of threshold spacing versus acuity, one point per patient, for several diagnostic groups, reveals the diagnostic power of flanked acuity testing. These results and two demonstrations indicate that the sensitivity of visual screening tests can be improved by using flankers that are more tightly spaced and letter like. Finally, in concert with Strappini, Pelli, Di Pace, and Martelli (submitted), we jointly report a double dissociation between acuity and crowding. Two clinical conditions—anisometropic amblyopia and apperceptive agnosia—each selectively impair either acuity A or the spacing:acuity ratio S/A, not both. Furthermore, when we specifically estimate crowding, we find a double dissociation between acuity and crowding. Models of human object recognition will need

  8. Acquisition of the Cardinal Principle Coincides with Improvement in Approximate Number System Acuity in Preschoolers

    PubMed Central

    Shusterman, Anna; Slusser, Emily; Halberda, Justin; Odic, Darko

    2016-01-01

    Human mathematical abilities comprise both learned, symbolic representations of number and unlearned, non-symbolic evolutionarily primitive cognitive systems for representing quantities. However, the mechanisms by which our symbolic (verbal) number system becomes integrated with the non-symbolic (non-verbal) representations of approximate magnitude (supported by the Approximate Number System, or ANS) are not well understood. To explore this connection, forty-six children participated in a 6-month longitudinal study assessing verbal number knowledge and non-verbal numerical acuity. Cross-sectional analyses revealed a strong relationship between verbal number knowledge and ANS acuity. Longitudinal analyses suggested that increases in ANS acuity were most strongly related to the acquisition of the cardinal principle, but not to other milestones of verbal number acquisition. These findings suggest that experience with culture and language is intimately linked to changes in the properties of a core cognitive system. PMID:27078257

  9. Acquisition of the Cardinal Principle Coincides with Improvement in Approximate Number System Acuity in Preschoolers.

    PubMed

    Shusterman, Anna; Slusser, Emily; Halberda, Justin; Odic, Darko

    2016-01-01

    Human mathematical abilities comprise both learned, symbolic representations of number and unlearned, non-symbolic evolutionarily primitive cognitive systems for representing quantities. However, the mechanisms by which our symbolic (verbal) number system becomes integrated with the non-symbolic (non-verbal) representations of approximate magnitude (supported by the Approximate Number System, or ANS) are not well understood. To explore this connection, forty-six children participated in a 6-month longitudinal study assessing verbal number knowledge and non-verbal numerical acuity. Cross-sectional analyses revealed a strong relationship between verbal number knowledge and ANS acuity. Longitudinal analyses suggested that increases in ANS acuity were most strongly related to the acquisition of the cardinal principle, but not to other milestones of verbal number acquisition. These findings suggest that experience with culture and language is intimately linked to changes in the properties of a core cognitive system. PMID:27078257

  10. A New Visual Stimulation Program for Improving Visual Acuity in Children with Visual Impairment: A Pilot Study.

    PubMed

    Tsai, Li-Ting; Hsu, Jung-Lung; Wu, Chien-Te; Chen, Chia-Ching; Su, Yu-Chin

    2016-01-01

    The purpose of this study was to investigate the effectiveness of visual rehabilitation of a computer-based visual stimulation (VS) program combining checkerboard pattern reversal (passive stimulation) with oddball stimuli (attentional modulation) for improving the visual acuity (VA) of visually impaired (VI) children and children with amblyopia and additional developmental problems. Six children (three females, three males; mean age = 3.9 ± 2.3 years) with impaired VA caused by deficits along the anterior and/or posterior visual pathways were recruited. Participants received eight rounds of VS training (two rounds per week) of at least eight sessions per round. Each session consisted of stimulation with 200 or 300 pattern reversals. Assessments of VA (assessed with the Lea symbol VA test or Teller VA cards), visual evoked potential (VEP), and functional vision (assessed with the Chinese-version Functional Vision Questionnaire, FVQ) were carried out before and after the VS program. Significant gains in VA were found after the VS training [VA = 1.05 logMAR ± 0.80 to 0.61 logMAR ± 0.53, Z = -2.20, asymptotic significance (2-tailed) = 0.028]. No significant changes were observed in the FVQ assessment [92.8 ± 12.6 to 100.8 ±SD = 15.4, Z = -1.46, asymptotic significance (2-tailed) = 0.144]. VEP measurement showed improvement in P100 latency and amplitude or integration of the waveform in two participants. Our results indicate that a computer-based VS program with passive checkerboard stimulation, oddball stimulus design, and interesting auditory feedback could be considered as a potential intervention option to improve the VA of a wide age range of VI children and children with impaired VA combined with other neurological disorders. PMID:27148014

  11. A New Visual Stimulation Program for Improving Visual Acuity in Children with Visual Impairment: A Pilot Study

    PubMed Central

    Tsai, Li-Ting; Hsu, Jung-Lung; Wu, Chien-Te; Chen, Chia-Ching; Su, Yu-Chin

    2016-01-01

    The purpose of this study was to investigate the effectiveness of visual rehabilitation of a computer-based visual stimulation (VS) program combining checkerboard pattern reversal (passive stimulation) with oddball stimuli (attentional modulation) for improving the visual acuity (VA) of visually impaired (VI) children and children with amblyopia and additional developmental problems. Six children (three females, three males; mean age = 3.9 ± 2.3 years) with impaired VA caused by deficits along the anterior and/or posterior visual pathways were recruited. Participants received eight rounds of VS training (two rounds per week) of at least eight sessions per round. Each session consisted of stimulation with 200 or 300 pattern reversals. Assessments of VA (assessed with the Lea symbol VA test or Teller VA cards), visual evoked potential (VEP), and functional vision (assessed with the Chinese-version Functional Vision Questionnaire, FVQ) were carried out before and after the VS program. Significant gains in VA were found after the VS training [VA = 1.05 logMAR ± 0.80 to 0.61 logMAR ± 0.53, Z = –2.20, asymptotic significance (2-tailed) = 0.028]. No significant changes were observed in the FVQ assessment [92.8 ± 12.6 to 100.8 ±SD = 15.4, Z = –1.46, asymptotic significance (2-tailed) = 0.144]. VEP measurement showed improvement in P100 latency and amplitude or integration of the waveform in two participants. Our results indicate that a computer-based VS program with passive checkerboard stimulation, oddball stimulus design, and interesting auditory feedback could be considered as a potential intervention option to improve the VA of a wide age range of VI children and children with impaired VA combined with other neurological disorders. PMID:27148014

  12. Influence of loupes and age on the near visual acuity of practicing dentists

    NASA Astrophysics Data System (ADS)

    Eichenberger, Martina; Perrin, Philippe; Neuhaus, Klaus W.; Bringolf, Ueli; Lussi, Adrian

    2011-03-01

    We evaluated the near visual acuity of 40 dentists and its improvement by using different magnification devices. The acuity was tested with miniaturized E-optotype tests on a negatoscope under the following conditions: 1. natural visual acuity, 300 mm; 2. single lens loupe, 2×, 250 mm; 3. Galilean loupe, 2.5×, 380 mm; and 4. Keplerian loupe, 4.3×, 400 mm. In part 1, the influence of the magnification devices was investigated for all dentists. The Keplerian loupe obtained the highest visual acuity (4.64), followed by the Galilean loupe (2.43), the single lens loupe (1.42), and natural visual acuity (1.19). For part 2, the dentists were classified according to their age (=40 years). The younger dentists' group achieved a significantly higher visual acuity with all magnification devices (p<0.001). For part 3, the dentists were grouped according to their natural visual acuity. The group with the higher natural visual acuity achieved significantly higher visual acuity with all magnification devices than did the group of dentists with the lower natural visual acuity (p<0.01). It can be concluded that near visual acuity varies highly between individuals and decreases during the lifetime. Independent of age or natural vision, visual acuity can be significantly improved by using magnification devices.

  13. Learning to Identify Near-Acuity Letters, either with or without Flankers, Results in Improved Letter Size and Spacing Limits in Adults with Amblyopia

    PubMed Central

    Chung, Susana T. L.; Li, Roger W.; Levi, Dennis M.

    2012-01-01

    Amblyopia is a developmental abnormality that results in deficits for a wide range of visual tasks, most notably, the reduced ability to see fine details, the loss in contrast sensitivity especially for small objects and the difficulty in seeing objects in clutter (crowding). The primary goal of this study was to evaluate whether crowding can be ameliorated in adults with amblyopia through perceptual learning using a flanked letter identification task that was designed to reduce crowding, and if so, whether the improvements transfer to untrained visual functions: visual acuity, contrast sensitivity and the size of visual span (the amount of information obtained in one fixation). To evaluate whether the improvements following this training task were specific to training with flankers, we also trained another group of adult observers with amblyopia using a single letter identification task that was designed to improve letter contrast sensitivity, not crowding. Following 10,000 trials of training, both groups of observers showed improvements in the respective training task. The improvements generalized to improved visual acuity, letter contrast sensitivity, size of the visual span, and reduced crowding. The magnitude of the improvement for each of these measurements was similar in the two training groups. Perceptual learning regimens aimed at reducing crowding or improving letter contrast sensitivity are both effective in improving visual acuity, contrast sensitivity for near-acuity objects and reducing the crowding effect, and could be useful as a clinical treatment for amblyopia. PMID:22558234

  14. Reducing Short-Wavelength Blue Light in Dry Eye Patients with Unstable Tear Film Improves Performance on Tests of Visual Acuity

    PubMed Central

    Kaido, Minako

    2016-01-01

    Purpose To investigate whether suppression of blue light can improve visual function in patients with short tear break up time (BUT) dry eye (DE). Methods Twenty-two patients with short BUT DE (10 men, 12 women; mean age, 32.4 ± 6.4 years; age range, 23–43 years) and 18 healthy controls (10 men, 8 women; mean age, 30.1 ± 7.4 years; age range, 20–49 years) underwent functional visual acuity (VA) examinations with and without wearing eyeglasses with 50% blue light blocked lenses. The functional VA parameters were starting VA, functional VA, and visual maintenance ratio. Results The baseline mean values (logarithm of the minimum angle of resolution, logMAR) of functional VA and the visual maintenance ratio were significantly worse in the DE patients than in the controls (P < 0.05), while no significant difference was observed in the baseline starting VA (P > 0.05). The DE patients had significant improvement in mean functional VA and visual maintenance ratio while wearing the glasses (P < 0.05), while there were no significant changes with and without the glasses in the control group (P > 0.05), Conclusions Protecting the eyes from short-wavelength blue light may help to ameliorate visual impairment associated with tear instability in patients with DE. This finding represents a new concept, which is that the blue light exposure might be harmful to visual function in patients with short BUT DE. PMID:27045760

  15. Tobias Mayer--experiments on visual acuity (1755).

    PubMed

    Scheerer, E

    1987-01-01

    The pioneering experimental work of Tobias Mayer (1723-1762) on visual acuity, published in 1755 in Latin, is presented in English translation. Mayer distinguished between two kinds of visual acuity, the one (30 arc sec) for single objects seen against a uniform background, the other (1 arc min) for more complex objects such as gratings, grids, or checkerboards. Strong illumination did not improve visual acuity. For targets seen in the light of a candle, the visual angle needed for resolution was inversely proportional to the cube root of the distance of the candle and therefore to the sixth root of 'brightness'. The historical significance of Mayer's work on visual acuity is briefly outlined. PMID:3154942

  16. Visual acuity test

    MedlinePlus

    Eye test -- acuity; Vision test -- acuity; Snellen test ... from your face. This will test your near vision. ... examination, particularly if there is a change in vision or a problem with vision. In children, the ...

  17. Acuity-driven gigapixel visualization.

    PubMed

    Papadopoulos, Charilaos; Kaufman, Arie E

    2013-12-01

    We present a framework for acuity-driven visualization of super-high resolution image data on gigapixel displays. Tiled display walls offer a large workspace that can be navigated physically by the user. Based on head tracking information, the physical characteristics of the tiled display and the formulation of visual acuity, we guide an out-of-core gigapixel rendering scheme by delivering high levels of detail only in places where it is perceivable to the user. We apply this principle to gigapixel image rendering through adaptive level of detail selection. Additionally, we have developed an acuity-driven tessellation scheme for high-quality Focus-and-Context (F+C) lenses that significantly reduces visual artifacts while accurately capturing the underlying lens function. We demonstrate this framework on the Reality Deck, an immersive gigapixel display. We present the results of a user study designed to quantify the impact of our acuity-driven rendering optimizations in the visual exploration process. We discovered no evidence suggesting a difference in search task performance between our framework and naive rendering of gigapixel resolution data, while realizing significant benefits in terms of data transfer overhead. Additionally, we show that our acuity-driven tessellation scheme offers substantially increased frame rates when compared to naive pre-tessellation, while providing indistinguishable image quality. PMID:24051856

  18. The Effect of Zeaxanthin on the Visual Acuity of Zebrafish

    PubMed Central

    Saidi, Eric A.; Davey, Pinakin Gunvant; Cameron, D. Joshua

    2015-01-01

    Oral supplementation of carotenoids such as zeaxanthin or lutein which naturally occur in human retina have been shown to improve vision and prevent progression of damage to advanced AMD in some studies. The zebrafish eye shares many physiological similarities with the human eye and is increasingly being used as model for vision research. We hypothesized that injection of zeaxanthin into the zebrafish eye would improve the visual acuity of the zebrafish over time. Visual acuity, calculated in cycles per degree, was measured in adult zebrafish to establish a consistent baseline using the optokinetic response. Zeaxanthin dissolved into phosphate buffered saline (PBS) or PBS only was injected into the anterior chamber of the right and left eyes of the Zebrafish. Visual acuities were measured at 1 week and 3, 8 and 12 weeks post-injection to compare to baseline values. Repeated measures ANOVA was used to compare visual acuities between fish injected with PBS and zeaxanthin. A significant improvement in visual acuity, 14% better than before the injection (baseline levels), was observed one week after injection with zeaxanthin (p = 0.04). This improvement peaked at more than 30% for some fish a few weeks after the injection and improvement in vision persisted at 3 weeks after injection (p = 0.006). The enhanced visual function was not significantly better than baseline at 8 weeks (p = 0.19) and returned to baseline levels 12 weeks after the initial injection (p = 0.50). Zeaxanthin can improve visual acuity in zebrafish eyes. Further studies are required to develop a better understanding of the role zeaxanthin and other carotenoids play during normal visual function. PMID:26267864

  19. New mobile technologies and visual acuity.

    PubMed

    Livingstone, I A T; Lok, A S L; Tarbert, C

    2014-01-01

    Mobile devices have shown promise in visual assessment. Traditional acuity measurement involves retro-illuminated charts or card-based modalities. Mobile platforms bring potential to improve on both portability and objectivity. The present research activity relates to design and validation of a novel tablet-based infant acuity test. Early results in an adult cohort, with various levels of artificially degraded vision, suggest improved test-retest reliability compared with current standards for infant acuity. Future pragmatic trials will assess the value of this emerging technology in pediatric visual screening. PMID:25570420

  20. A single cohort prospective trial of the immediate effects of spinal manipulation on visual acuity

    PubMed Central

    Athaide, Michelle; Rego, Carol; Budgell, Brian

    2016-01-01

    Introduction: There is no high quality evidence on which to judge the generalizability of isolated reports of improvement in vision following manipulation. The current paucity of research results also precludes the thoughtful design of a controlled, prospective clinical study. Hence, the purpose of the current study was to test the feasibility of conducting a clinical trial of the acute effects of spinal manipulation on visual acuity. Methods: New adult patients presenting to a community based chiropractic clinic were recruited into a single cohort prospective trial to determine the immediate effects of cervical spinal manipulation on visual acuity. Results: The experimental protocol was well accepted by patients and caused minimal or no disruption of the clinic routine. By some measures, chiropractic treatment was accompanied by statistically significant improvements in visual acuity. Discussion: The results of this study indicate that it is quite feasible to conduct a prospective, community based clinical study of the acute effects of spinal manipulation on visual acuity. PMID:27069271

  1. Acuity systems dialogue and patient classification system essentials.

    PubMed

    Harper, Kelle; McCully, Crystal

    2007-01-01

    Obtaining resources for quality patient care is a major responsibility of nurse leaders and requires accurate information in the political world of budgeting. Patient classification systems (PCS) assist nurse managers in controlling cost and improving patient care while appropriately using financial resources. This paper communicates acuity systems development, background, flaws, and components while discussing a few tools currently available. It also disseminates the development of a new acuity tool, the Patient Classification System. The PCS tool, developed in a small rural hospital, uses 5 broad concepts: (1) medications, (2) complicated procedures, (3) education, (4) psychosocial issues, and (5) complicated intravenous medications. These concepts embrace a 4-tiered scale that differentiates significant patient characteristics and assists in staffing measures for equality in patient staffing and improving quality of care and performance. Data obtained through use of the PCS can be used by nurse leaders to effectively and objectively lobby for appropriate patient care resources. Two questionnaires distributed to registered nurses on a medical-surgical unit evaluated the nurses' opinion of the 5 concepts and the importance for establishing patient acuity for in-patient care. Interrater reliability among nurses was 87% with the author's acuity tool. PMID:17909428

  2. Preschool visual acuity screening tests.

    PubMed Central

    Friendly, D S

    1978-01-01

    The purpose of the study was to evaluate the relative merits of two screening tests used for visual acuity assessment of preschool children. The tests that were compared were the Good-Lite Company versions of the E-Test and of the STYCAR (Screening Test for Young Children and Retardates). The former is the most popular method for evaluating central acuity in young children in this nation; the STYCAR is a relatively new letter-matching-test developed in England, where it is widely employed. The E-Test poses left-right orientation problems which are eliminated by the symmetrical letters H, T, O and V utilized in the Letter-Matching-Test. Both visual acuity tests were administered on two separate occasions by personnel from the Prevention of Blindness Society of Metropolitan Washington to 633 preschool children in Washington, D.C. By random selection, 150 of the children received the E-Test at both sessions, 162 children received the Letter-Matching-Test at both sessions, 160 chilt athe the second session, and 161 children received the Letter-Matching-Test at the first session and the E-Test at the second session. The author medically examined the eyes of 408 of the 633 children without knowledge of which test had been initially administered. Statistical analysis of the data obtained from the study indicated that the Letter-Matching-Test was significantly better in terms of testability rates, group and individual instruction time, and performance time. The E-Test was more reliable in terms of test-retest acuity scores and was also more valid in terms of agreement between pass-fail results obtained at the first screening session and two levels of pass-fail refraction criteria. Images FIGURE 4 FIGURE 5 FIGURE 7 A FIGURE 7 B FIGURE 9 A FIGURE 9 B PMID:754379

  3. Recent BRCAPRO upgrades significantly improve calibration

    PubMed Central

    Mazzola, Emanuele; Chipman, Jonathan; Cheng, Su-Chun; Parmigiani, Giovanni

    2014-01-01

    The recent release of version 2.0-8 of the BayesMendel package contains an updated BRCAPRO risk prediction model, which includes revised modeling of Contralateral Breast Cancer (CBC) penetrance, provisions for pedigrees of mixed ethnicity and an adjustment for mastectomies among family members. We estimated penetrance functions for contralateral breast cancer by a combination of parametric survival modeling of literature data and deconvolution of SEER9 data. We then validated the resulting updated model of CBC in BRCAPRO by comparing it with the previous release (BayesMendel 2.0-7), using pedigrees from the Cancer Genetics Network (CGN) Model Validation Study. Version 2.0-8 of BRCAPRO discriminates BRCA1/BRCA2 carriers from non-carriers with similar accuracy compared to the previous version (increase in AUC: 0.0043), is slightly more precise in terms of RMSE (decrease in RMSE: 0.0108), and it significantly improves calibration (ratio of observed to expected events of 0.9765 in version 2.0-8, compared to 0.8910 in version 2.0-7). We recommend that the new version be used in clinical counseling, particularly in settings where families with CBC are common. PMID:24891549

  4. The importance of measuring dynamic visual acuity.

    PubMed

    Muzdalo, Natasa Vujko

    2013-04-01

    In their everyday life, people interact with different objects, static as well as those in motion. However, dynamic acuity is rarely checked in medical examinations, even those preceding the issue of driving license. In order for driving to be safe, good eyesight or good correction with visual aids is imperative. Beside good eyesight, drivers also have to have good reflexes and short reaction span. The aim of this study was to compare dynamic and static visual acuity in order to observe how they vary among individuals. Twenty female and male participants, 65 years of age, took part in the study and the comparison was made with the results provided by 20 20-year old participants. Dynamic acuity was tested using the Landolt-ring optotype which was simulating movement velocity of 72 km/h. T-test demonstrated the presence of a statistically significant difference between dynamic and static acuity among the participants from 62 to 68 years of age (t = 15.852; df = 39; p < 0.01). Within the same group, dynamic acuity (mean = 0.887; std. deviation = 0.297) proved to be significantly worse than static acuity (mean = 1.40; std. deviation = 0.317). By comparing the results measured within the older group of participants with those measured in the younger group, it was shown that there exists a statistically significant difference (t = 0.275; df = 58; p < 0,05) between the older and younger group in their dynamic binocular acuity with correction. Younger participants had better dynamic binocular acuity with correction (mean = 1.063; std. deviation = 0.259) than the older participants (mean = 0.884; std. deviation = 0.298). The differences between dynamic and static acuity and its degradation in the older age groups have to be taken into account when issuing driving licenses. The future of research lies within the study of correlation between the age and acuity in order that the results can be applied in practice. PMID:23837257

  5. Dynamic Visual Acuity: a Functionally Relevant Research Tool

    NASA Technical Reports Server (NTRS)

    Peters, Brian T.; Brady, Rachel A.; Miller, Chris A.; Mulavara, Ajitkumar P.; Wood, Scott J.; Cohen, Helen S.; Bloomberg, Jacob J.

    2010-01-01

    Coordinated movements between the eyes and head are required to maintain a stable retinal image during head and body motion. The vestibulo-ocular reflex (VOR) plays a significant role in this gaze control system that functions well for most daily activities. However, certain environmental conditions or interruptions in normal VOR function can lead to inadequate ocular compensation, resulting in oscillopsia, or blurred vision. It is therefore possible to use acuity to determine when the environmental conditions, VOR function, or the combination of the two is not conductive for maintaining clear vision. Over several years we have designed and tested several tests of dynamic visual acuity (DVA). Early tests used the difference between standing and walking acuity to assess decrements in the gaze stabilization system after spaceflight. Supporting ground-based studies measured the responses from patients with bilateral vestibular dysfunction and explored the effects of visual target viewing distance and gait cycle events on walking acuity. Results from these studies show that DVA is affected by spaceflight, is degraded in patients with vestibular dysfunction, changes with target distance, and is not consistent across the gait cycle. We have recently expanded our research to include studies in which seated subjects are translated or rotated passively. Preliminary results from this work indicate that gaze stabilization ability may differ between similar active and passive conditions, may change with age, and can be affected by the location of the visual target with respect to the axis of motion. Use of DVA as a diagnostic tool is becoming more popular but the functional nature of the acuity outcome measure also makes it ideal for identifying conditions that could lead to degraded vision. By doing so, steps can be taken to alter the problematic environments to improve the man-machine interface and optimize performance.

  6. Grating Visual Acuity Results in the Early Treatment for Retinopathy of Prematurity Study

    PubMed Central

    2015-01-01

    Objective To compare grating (resolution) visual acuity at 6 years of age in eyes that received early treatment (ET) for high-risk prethreshold retinopathy of prematurity (ROP) versus eyes that were managed conventionally (CM). Methods In a randomized clinical trial, infants with bilateral, high-risk prethreshold ROP (N=317) had one eye treated early at high-risk prethreshold disease and the other eye managed conventionally, and treated if ROP progressed to threshold severity. For asymmetric cases (N=84), the high-risk prethreshold eye was randomized to either ET or CM. Main Outcome Measures Grating visual acuity measured at 6 years of age by masked testers using Teller acuity cards. Results Monocular grating acuity results were obtained from 317 (86%) of 370 surviving children. Analysis of grating acuity results for all subjects with high-risk prethreshold ROP showed no statistically significant overall benefit for early treatment (18.1% vs 22.8% unfavorable outcome, P=0.08). When the 6-year grating acuity results were analyzed according to a clinical algorithm (high-risk Type 1 and high-risk Type 2 prethreshold ROP), a benefit was seen in Type 1 eyes (16.4% vs 25.2%, P=0.004) that were treated early, but not in Type 2 eyes (21.3% vs 15.9%, P=0.29). Conclusion Early treatment for eyes with Type 1 ROP improved grating acuity outcomes but early treatment for eyes with Type 2 ROP did not. Application to Clinical Medicine Type I eyes should be treated early; however, based on acuity results at age 6 years, Type 2 eyes should be cautiously monitored for progression to Type 1 ROP. Trial Registration NCT00027222 PMID:21746974

  7. Relation between uncorrected astigmatism and visual acuity in pseudophakia.

    PubMed

    Singh, Archana; Pesala, Veerendranath; Garg, Prashant; Bharadwaj, Shrikant R

    2013-04-01

    PURPOSE.: The end point of astigmatic correction after cataract surgery will depend on how uncorrected astigmatism impacts distance and near vision of pseudophakic eyes. This study determined the impact of induced astigmatism and pupil size on the distance and near acuity of otherwise emmetropic pseudophakic eyes implanted with monofocal intraocular lenses. METHODS.: Monocular high-contrast distance (4 m) and near (40 cm) logMAR acuity was determined in 15 subjects (mean ± 1 SD, 57.9 ± 9.0 years) without astigmatism and with 2.5 diopters (D) myopic to 2.0 D hyperopic astigmatic lenses induced in 0.5-D steps at 0-, 45-, 90-, and 135-degree axes. This experiment was repeated for the same range of induced astigmatism with 1.5-, 3-, and 6-mm artificial pupil diameters placed before one eye of 10 subjects dilated with 10% phenylephrine HCl. RESULTS.: Distance acuity deteriorated with astigmatism for all axes tested (p < 0.01). Near acuity deteriorated with hyperopic astigmatism (p < 0.1), whereas it improved with up to 1 D of myopic astigmatism before saturating for all axes tested (p < 0.01). Distance and near acuity improved with a reduction in pupil diameter (p < 0.01). The change in distance and near acuity with induced astigmatism was smaller for 1.5-mm than for 3-mm and 6-mm pupil diameters (p < 0.01). CONCLUSIONS.: Partial restoration of near acuity with uncorrected myopic astigmatism comes with a proportional loss of distance acuity in pseudophakic eyes. Uncorrected myopic astigmatism more than 1 D results in a large loss of distance acuity at no additional benefit to near acuity. Both distance and near acuities with and without astigmatism are benefited with a reduction in pupil diameter. Uncorrected hyperopic astigmatism results in deterioration of both distance and near acuities of pseudophakic eyes. PMID:23458979

  8. Set shot shooting performance and visual acuity in basketball.

    PubMed

    Applegate, R A; Applegate, R A

    1992-10-01

    Common sense suggests that decreasing visual acuity will have a negative effect on basketball shooting performance. To test the hypothesis that basketball shooting performance monotonically decreases with decreasing acuity, 19 subjects attempted 25 set shots from a fixed location at each of 5 different acuity levels: 6/6 or better and vision blurred (by optical defocus) to visual acuities of 6/12, 6/24, 6/48, and 6/75. Our results revealed a small but statistically nonsignificant decrease in shooting performance between the 6/6+ and 6/12 conditions. For visual acuities between 6/12 and 6/75, the number of baskets made remained constant. We conclude that decreases in visual acuity over the range of 6/6+ to 6/75 resulting from defocus do not significantly reduce set shot shooting performance. PMID:1436997

  9. Tactile Acuity Charts: A Reliable Measure of Spatial Acuity

    PubMed Central

    Bruns, Patrick; Camargo, Carlos J.; Campanella, Humberto; Esteve, Jaume; Dinse, Hubert R.; Röder, Brigitte

    2014-01-01

    For assessing tactile spatial resolution it has recently been recommended to use tactile acuity charts which follow the design principles of the Snellen letter charts for visual acuity and involve active touch. However, it is currently unknown whether acuity thresholds obtained with this newly developed psychophysical procedure are in accordance with established measures of tactile acuity that involve passive contact with fixed duration and control of contact force. Here we directly compared tactile acuity thresholds obtained with the acuity charts to traditional two-point and grating orientation thresholds in a group of young healthy adults. For this purpose, two types of charts, using either Braille-like dot patterns or embossed Landolt rings with different orientations, were adapted from previous studies. Measurements with the two types of charts were equivalent, but generally more reliable with the dot pattern chart. A comparison with the two-point and grating orientation task data showed that the test-retest reliability of the acuity chart measurements after one week was superior to that of the passive methods. Individual thresholds obtained with the acuity charts agreed reasonably with the grating orientation threshold, but less so with the two-point threshold that yielded relatively distinct acuity estimates compared to the other methods. This potentially considerable amount of mismatch between different measures of tactile acuity suggests that tactile spatial resolution is a complex entity that should ideally be measured with different methods in parallel. The simple test procedure and high reliability of the acuity charts makes them a promising complement and alternative to the traditional two-point and grating orientation thresholds. PMID:24504346

  10. Comparison of acuity tests and pattern evoked potential criteria: two mechanisms underly acuity maturation in man.

    PubMed

    Spekreijse, H

    1983-10-01

    A comparative study of acuity tests and pattern evoked potential (EP) criteria was performed on a total of 307 subjects, 214 of them at an age between 2 months post-term and 12 years. All were examined ophthalmologically prior to testing. It was shown that both psychophysical and EP estimated acuity improve in the same way until puberty. From birth to about 6 months a rapid improvement is found. This fast phase can probably be attributed to retinal morphological maturation. During this period a fair estimate of acuity can be obtained by determining the checksize that yields the largest EP; a conclusion of practical importance for screening. The subsequent slow improvement phase, which ends around puberty, is reflected in the development of the waveform of the pattern onset EP. Since it correlates with the growth of a spatial contrast specific component of extrastriate origin in the EP, the slow improvement phase most likely reflects maturation of central processes. PMID:6639719

  11. Dot Display Affects Approximate Number System Acuity and Relationships with Mathematical Achievement and Inhibitory Control

    PubMed Central

    Norris, Jade Eloise; Castronovo, Julie

    2016-01-01

    Much research has investigated the relationship between the Approximate Number System (ANS) and mathematical achievement, with continued debate surrounding the existence of such a link. The use of different stimulus displays may account for discrepancies in the findings. Indeed, closer scrutiny of the literature suggests that studies supporting a link between ANS acuity and mathematical achievement in adults have mostly measured the ANS using spatially intermixed displays (e.g. of blue and yellow dots), whereas those failing to replicate a link have primarily used spatially separated dot displays. The current study directly compared ANS acuity when using intermixed or separate dots, investigating how such methodological variation mediated the relationship between ANS acuity and mathematical achievement. ANS acuity was poorer and less reliable when measured with intermixed displays, with performance during both conditions related to inhibitory control. Crucially, mathematical achievement was significantly related to ANS accuracy difference (accuracy on congruent trials minus accuracy on incongruent trials) when measured with intermixed displays, but not with separate displays. The findings indicate that methodological variation affects ANS acuity outcomes, as well as the apparent relationship between the ANS and mathematical achievement. Moreover, the current study highlights the problem of low reliabilities of ANS measures. Further research is required to construct ANS measures with improved reliability, and to understand which processes may be responsible for the increased likelihood of finding a correlation between the ANS and mathematical achievement when using intermixed displays. PMID:27195749

  12. Short-Term Visual Deprivation, Tactile Acuity, and Haptic Solid Shape Discrimination

    PubMed Central

    Crabtree, Charles E.; Norman, J. Farley

    2014-01-01

    Previous psychophysical studies have reported conflicting results concerning the effects of short-term visual deprivation upon tactile acuity. Some studies have found that 45 to 90 minutes of total light deprivation produce significant improvements in participants' tactile acuity as measured with a grating orientation discrimination task. In contrast, a single 2011 study found no such improvement while attempting to replicate these earlier findings. A primary goal of the current experiment was to resolve this discrepancy in the literature by evaluating the effects of a 90-minute period of total light deprivation upon tactile grating orientation discrimination. We also evaluated the potential effect of short-term deprivation upon haptic 3-D shape discrimination using a set of naturally-shaped solid objects. According to previous research, short-term deprivation enhances performance in a tactile 2-D shape discrimination task – perhaps a similar improvement also occurs for haptic 3-D shape discrimination. The results of the current investigation demonstrate that not only does short-term visual deprivation not enhance tactile acuity, it additionally has no effect upon haptic 3-D shape discrimination. While visual deprivation had no effect in our study, there was a significant effect of experience and learning for the grating orientation task – the participants' tactile acuity improved over time, independent of whether they had, or had not, experienced visual deprivation. PMID:25397327

  13. Coincidence anticipation and dynamic visual acuity in young adolescents.

    PubMed

    Millslagle, Duane

    2004-12-01

    Research involving college-age students and women fast pitch softball players indicated that coincidence anticipation and dynamic visual acuity are different visual abilities. This study used an alternative procedure to measure dynamic visual acuity to re-examine their relationship. Coincidence anticipation and dynamic visual acuity were measured in 24 young adolescents (12 boys, 12 girls) 11 to 14 years of age. During the dynamic visual acuity procedure, the subject tracked an object of a constant size while the researcher manipulated the object's velocity. Analysis indicated that they are different visual abilities. Findings indicated that the dynamic visual acuity of boys was significantly better than that of girls, and coincidence anticipation between boys and girls did not differ. PMID:15739838

  14. Tactile acuity training for patients with chronic low back pain: a pilot randomised controlled trial

    PubMed Central

    2014-01-01

    Background Chronic pain can disrupt the cortical representation of a painful body part. This disruption may play a role in maintaining the individual’s pain. Tactile acuity training has been used to normalise cortical representation and reduce pain in certain pain conditions. However, there is little evidence for the effectiveness of this intervention for chronic low back pain (CLBP). The primary aim of this study was to inform the development of a fully powered randomised controlled trial (RCT) by providing preliminary data on the effect of tactile acuity training on pain and function in individuals with CLBP. The secondary aim was to obtain qualitative feedback about the intervention. Methods In this mixed-methods pilot RCT 15 individuals were randomised to either an intervention (tactile acuity training) or a placebo group (sham tactile acuity training). All participants received 3 sessions of acuity training (intervention or sham) from a physiotherapist and were requested to undertake daily acuity home training facilitated by an informal carer (friend/relative). All participants also received usual care physiotherapy. The primary outcome measures were pain (0-100visual analogue scale (VAS)) and function (Roland Morris Disability Questionnaire (RMDQ)). Participants and their informal carers were invited to a focus group to provide feedback on the intervention. Results The placebo group improved by the greatest magnitude for both outcome measures, but there was no statistically significant difference (Mean difference (95%CI), p-value) between groups for change in pain (25.6 (-0.7 to 51.9), p = 0.056) or function (2.2 (-1.6 to 6.0), p = 0.237). Comparing the number of individuals achieving a minimally clinically significant improvement, the placebo group had better outcomes for pain with all participants achieving ≥30% improvement compared to only a third of the intervention group (6/6 vs. 3/9, p = 0.036). Qualitatively, participants reported that

  15. Photometric Compliance of Tablet Screens and Retro-Illuminated Acuity Charts As Visual Acuity Measurement Devices

    PubMed Central

    Livingstone, I. A. T.; Tarbert, C. M.; Giardini, M. E.; Bastawrous, A.; Middleton, D.; Hamilton, R.

    2016-01-01

    Mobile technology is increasingly used to measure visual acuity. Standards for chart-based acuity tests specify photometric requirements for luminance, optotype contrast and luminance uniformity. Manufacturers provide some photometric data but little is known about tablet performance for visual acuity testing. This study photometrically characterised seven tablet computers (iPad, Apple inc.) and three ETDRS (Early Treatment Diabetic Retinopathy Study) visual acuity charts with room lights on and off, and compared findings with visual acuity measurement standards. Tablet screen luminance and contrast were measured using nine points across a black and white checkerboard test screen at five arbitrary brightness levels. ETDRS optotypes and adjacent white background luminance and contrast were measured. All seven tablets (room lights off) exceeded the most stringent requirement for mean luminance (≥ 120 cd/m2) providing the nominal brightness setting was above 50%. All exceeded contrast requirement (Weber ≥ 90%) regardless of brightness setting, and five were marginally below the required luminance uniformity threshold (Lmin/Lmax ≥ 80%). Re-assessing three tablets with room lights on made little difference to mean luminance or contrast, and improved luminance uniformity to exceed the threshold. The three EDTRS charts (room lights off) had adequate mean luminance (≥ 120 cd/m2) and Weber contrast (≥ 90%), but all three charts failed to meet the luminance uniformity standard (Lmin/Lmax ≥ 80%). Two charts were operating beyond manufacturer’s recommended lamp replacement schedule. With room lights on, chart mean luminance and Weber contrast increased, but two charts still had inadequate luminance uniformity. Tablet computers showed less inter-device variability, higher contrast, and better luminance uniformity than charts in both lights-on and lights-off environments, providing brightness setting was >50%. Overall, iPad tablets matched or marginally out

  16. Photometric Compliance of Tablet Screens and Retro-Illuminated Acuity Charts As Visual Acuity Measurement Devices.

    PubMed

    Livingstone, I A T; Tarbert, C M; Giardini, M E; Bastawrous, A; Middleton, D; Hamilton, R

    2016-01-01

    Mobile technology is increasingly used to measure visual acuity. Standards for chart-based acuity tests specify photometric requirements for luminance, optotype contrast and luminance uniformity. Manufacturers provide some photometric data but little is known about tablet performance for visual acuity testing. This study photometrically characterised seven tablet computers (iPad, Apple inc.) and three ETDRS (Early Treatment Diabetic Retinopathy Study) visual acuity charts with room lights on and off, and compared findings with visual acuity measurement standards. Tablet screen luminance and contrast were measured using nine points across a black and white checkerboard test screen at five arbitrary brightness levels. ETDRS optotypes and adjacent white background luminance and contrast were measured. All seven tablets (room lights off) exceeded the most stringent requirement for mean luminance (≥ 120 cd/m2) providing the nominal brightness setting was above 50%. All exceeded contrast requirement (Weber ≥ 90%) regardless of brightness setting, and five were marginally below the required luminance uniformity threshold (Lmin/Lmax ≥ 80%). Re-assessing three tablets with room lights on made little difference to mean luminance or contrast, and improved luminance uniformity to exceed the threshold. The three EDTRS charts (room lights off) had adequate mean luminance (≥ 120 cd/m2) and Weber contrast (≥ 90%), but all three charts failed to meet the luminance uniformity standard (Lmin/Lmax ≥ 80%). Two charts were operating beyond manufacturer's recommended lamp replacement schedule. With room lights on, chart mean luminance and Weber contrast increased, but two charts still had inadequate luminance uniformity. Tablet computers showed less inter-device variability, higher contrast, and better luminance uniformity than charts in both lights-on and lights-off environments, providing brightness setting was >50%. Overall, iPad tablets matched or marginally out

  17. The Frequency of Decreased Visual Acuity in Orbital Fractures.

    PubMed

    Kim, Yeon Soo; Kim, Joo Ho; Hwang, Kun

    2015-07-01

    The aim of this systematic review is to summarize and evaluate the effect of orbital fractures (blowout fractures and nonblowout fractures) on visual acuity. In PubMed search and Scopus search, the terms "orbital fracture OR maxillofacial injury OR facial trauma OR craniofacial fracture," and "visual acuity OR functional outcome OR visual outcome OR improving document of visual acuity OR blindness OR optic nerve neuropathy" were used, which resulted in 1634 and 1152 papers, respectively. Of the 2226 titles excluding 560 duplicated titles, 227 abstracts were reviewed. Of the 227 abstracts reviewed, the authors found 56 potentially relevant full-text articles, of which 5 studies met our inclusion criteria. The odds ratio and 95% confidence intervals from each study were abstracted. The statistical analysis was performed with review manager (The Nordic Cochrane Centre). A summary of 5 studies affirmed that 43 patients among 532 orbital fractures (8.1%) had decreased visual acuity. Twelve patients among 159 blowout fractures (7.5%) had decreased visual acuity. Thirty-one patients among 373 orbital fractures other than pure blowout fractures (8.3%) had decreased visual acuity. In orbital fractures other than pure blowout fractures, the frequency of decreased visual acuity was higher than pure blowout fractures (n = 532, odds ratio, 2.23, 95% confidence interval = 1.06-4.70). Surgeons should acknowledge this with patients before surgery. PMID:26114513

  18. The development of an obstetric triage acuity tool.

    PubMed

    Paisley, Kathleen S; Wallace, Ruth; DuRant, Patricia G

    2011-01-01

    The purpose of this article is to describe the journey a multicampus hospital system took to improve the obstetric triage process. A review of literature revealed no current comprehensive obstetric acuity tool, and thus our team developed a tool with a patient flow process, revised and updated triage nurse competencies, and then educated the nurses about the new tool and process. Data were collected to assess the functionality of the new process in assigning acuity upon patient arrival, conveying appropriate acuities based on patient complaints, and initiating the medical screening examination, all within prescribed time intervals. Initially data indicated that processes were still not optimal, and re-education was provided for all triage nurses. This improved all data points. The result of this QI project is that our patients are now seen based on their acuity within designated time frames. PMID:21857199

  19. Visual Acuity and the Eye.

    ERIC Educational Resources Information Center

    Beynon, J.

    1985-01-01

    Shows that visual acuity is a function of the structure of the eye and that its limit is set by the structure of the retina, emphasizing the role of lens aberrations and difraction on image quality. Also compares human vision with that of other vertebrates and insects. (JN)

  20. Olfactory acuity in theropods: palaeobiological and evolutionary implications

    PubMed Central

    Zelenitsky, Darla K.; Therrien, François; Kobayashi, Yoshitsugu

    2008-01-01

    This research presents the first quantitative evaluation of the olfactory acuity in extinct theropod dinosaurs. Olfactory ratios (i.e. the ratio of the greatest diameter of the olfactory bulb to the greatest diameter of the cerebral hemisphere) are analysed in order to infer the olfactory acuity and behavioural traits in theropods, as well as to identify phylogenetic trends in olfaction within Theropoda. A phylogenetically corrected regression of olfactory ratio to body mass reveals that, relative to predicted values, the olfactory bulbs of (i) tyrannosaurids and dromaeosaurids are significantly larger, (ii) ornithomimosaurs and oviraptorids are significantly smaller, and (iii) ceratosaurians, allosauroids, basal tyrannosauroids, troodontids and basal birds are within the 95% CI. Relative to other theropods, olfactory acuity was high in tyrannosaurids and dromaeosaurids and therefore olfaction would have played an important role in their ecology, possibly for activities in low-light conditions, locating food, or for navigation within large home ranges. Olfactory acuity was the lowest in ornithomimosaurs and oviraptorids, suggesting a reduced reliance on olfaction and perhaps an omnivorous diet in these theropods. Phylogenetic trends in olfaction among theropods reveal that olfactory acuity did not decrease in the ancestry of birds, as troodontids, dromaeosaurids and primitive birds possessed typical or high olfactory acuity. Thus, the sense of smell must have remained important in primitive birds and its presumed decrease associated with the increased importance of sight did not occur until later among more derived birds. PMID:18957367

  1. Binocular visual acuity for the correction of spherical aberration in polychromatic and monochromatic light.

    PubMed

    Schwarz, Christina; Cánovas, Carmen; Manzanera, Silvestre; Weeber, Henk; Prieto, Pedro M; Piers, Patricia; Artal, Pablo

    2014-01-01

    Correction of spherical (SA) and longitudinal chromatic aberrations (LCA) significantly improves monocular visual acuity (VA). In this work, the visual effect of SA correction in polychromatic and monochromatic light on binocular visual performance is investigated. A liquid crystal based binocular adaptive optics visual analyzer capable of operating in polychromatic light is employed in this study. Binocular VA improves when SA is corrected and LCA effects are reduced separately and in combination, resulting in the highest value for SA correction in monochromatic light. However, the binocular summation ratio is highest for the baseline condition of uncorrected SA in polychromatic light. Although SA correction in monochromatic light has a greater impact monocularly than binocularly, bilateral correction of both SA and LCA may further improve binocular spatial visual acuity which may support the use of aspheric-achromatic ophthalmic devices, in particular, intraocular lenses (IOLs). PMID:24520150

  2. Gains following perceptual learning are closely linked to the initial visual acuity

    PubMed Central

    Yehezkel, Oren; Sterkin, Anna; Lev, Maria; Levi, Dennis M.; Polat, Uri

    2016-01-01

    The goal of the present study was to evaluate the dependence of perceptual learning gains on initial visual acuity (VA), in a large sample of subjects with a wide range of VAs. A large sample of normally sighted and presbyopic subjects (N = 119; aged 40 to 63) with a wide range of uncorrected near visual acuities (VA, −0.12 to 0.8 LogMAR), underwent perceptual learning. Training consisted of detecting briefly presented Gabor stimuli under spatial and temporal masking conditions. Consistent with previous findings, perceptual learning induced a significant improvement in near VA and reading speed under conditions of limited exposure duration. Our results show that the improvements in VA and reading speed observed following perceptual learning are closely linked to the initial VA, with only a minor fraction of the observed improvement that may be attributed to the additional sessions performed by those with the worse VA. PMID:27122254

  3. Visual acuity in mammals: effects of eye size and ecology.

    PubMed

    Veilleux, Carrie C; Kirk, E Christopher

    2014-01-01

    Previous comparative research has attributed interspecific variation in eye size among mammals to selection related to visual acuity. Mammalian species have also been hypothesized to differ in visual acuity partly as a result of differences in ecology. While a number of prior studies have explored ecological and phylogenetic effects on eye shape, a broad comparative analysis of the relationships between visual acuity, eye size and ecology in mammals is currently lacking. Here we use phylogenetic comparative methods to explore these relationships in a taxonomically and ecologically diverse sample of 91 mammal species. These data confirm that axial eye length and visual acuity are significantly positively correlated in mammals. This relationship conforms to expectations based on theoretical optics and prior analyses of smaller comparative samples. Our data also demonstrate that higher visual acuity in mammals is associated with: (1) diurnality and (2) predatory habits once the effects of eye size and phylogeny have been statistically controlled. These results suggest that interspecific variation in mammalian visual acuity is the result of a complex interplay between phylogenetic history, visual anatomy and ecology. PMID:24603494

  4. Preferential looking and recognition acuities in clinical amblyopia.

    PubMed

    Mandava, N; Simon, J W; Jenkins, P L

    1991-01-01

    Although others have noted a correlation between grating and recognition acuities (RA) when both tests are performed on the same day, the value of preferential looking (PL) in predicting eventual visual outcome has not been studied. PL acuities of 64 preverbal patients considered at risk of amblyopia were measured. When these children became verbal, their visual acuities were determined using standard recognition acuity tests. Based on intervening amblyopia treatment between PL and RA measures, 40 patients were designated the minimal treatment group (MTG) and 24 the intensive treatment group (ITG). Chi-square analysis for the MTG showed agreement (P less than .005) between PL and RA in identifying better, equal, and worse eyes. Interocular ratios of PL and RA were significantly correlated for the MTG (P less than .001), but not for the ITG. Monocularly, a consistent correlation between PL and RA was not found. Our data suggest that PL is predictive of recognition acuity in patients whose visual acuity was expected to remain stable. PMID:1757857

  5. Visual acuity and pupillary reactions after peribulbar anaesthesia.

    PubMed Central

    Talks, S J; Chong, N H; Gibson, J M; Francis, I R

    1994-01-01

    The effect of peribulbar anaesthesia on optic nerve function in 20 patients, before and after cataract surgery, was measured. All the patients had decreased visual acuity. Five (25%) had no perception of light. Seventeen (85%) developed a relative afferent pupil defect (RAPD). No patients saw the operating instruments. Seven (35%) had improved visual acuity immediately postoperatively. Patients should be warned that they may lose vision completely on being given a peribulbar anaesthetic; however their vision will improve, but not necessarily immediately, postoperatively. Examination for an RAPD is a good method of providing reassurance that the operating instruments will not be seen. PMID:8110698

  6. Response Classification Images in Vernier Acuity

    NASA Technical Reports Server (NTRS)

    Ahumada, Albert J., Jr.; Beard, B. L.; Ellis, Stephen R. (Technical Monitor)

    1997-01-01

    Orientation selective and local sign mechanisms have been proposed as the basis for vernier acuity judgments. Linear image features contributing to discrimination can be determined for a two choice task by adding external noise to the images and then averaging the noises separately for the four types of stimulus/response trials. This method is applied to a vernier acuity task with different spatial separations to compare the predictions of the two theories. Three well-practiced observers were presented around 5000 trials of a vernier stimulus consisting of two dark horizontal lines (5 min by 0.3 min) within additive low-contrast white noise. Two spatial separations were tested, abutting and a 10 min horizontal separation. The task was to determine whether the target lines were aligned or vertically offset. The noises were averaged separately for the four stimulus/response trial types (e.g., stimulus = offset, response = aligned). The sum of the two 'not aligned' images was then subtracted from the sum of the 'aligned' images to obtain an overall image. Spatially smoothed images were quantized according to expected variability in the smoothed images to allow estimation of the statistical significance of image features. The response images from the 10 min separation condition are consistent with the local sign theory, having the appearance of two linear operators measuring vertical position with opposite sign. The images from the abutting stimulus have the same appearance with the two operators closer together. The image predicted by an oriented filter model is similar, but has its greatest weight in the abutting region, while the response images fall to nonsignificance there. The response correlation image method, previously demonstrated for letter discrimination, clarifies the features used in vernier acuity.

  7. Significant improvements in long trace profiler measurement performance

    SciTech Connect

    Takacs, P.Z.; Bresloff, C.J.

    1996-07-01

    A Modifications made to the Long Trace Profiler (LTP II) system at the Advanced Photon Source at Argonne National Laboratory have significantly improved the accuracy and repeatability of the instrument The use of a Dove prism in the reference beam path corrects for phasing problems between mechanical efforts and thermally-induced system errors. A single reference correction now completely removes both error signals from the measured surface profile. The addition of a precision air conditioner keeps the temperature in the metrology enclosure constant to within {+-}0.1{degrees}C over a 24 hour period and has significantly improved the stability and repeatability of the system. We illustrate the performance improvements with several sets of measurements. The improved environmental control has reduced thermal drift error to about 0.75 microradian RMS over a 7.5 hour time period. Measurements made in the forward scan direction and the reverse scan direction differ by only about 0.5 microradian RMS over a 500mm, trace length. We are now able to put 1-sigma error bar of 0.3 microradian on an average of 10 slope profile measurements over a 500mm long trace length, and we are now able to put a 0.2 microradian error bar on an average of 10 measurements over a 200mm trace length. The corresponding 1-sigma height error bar for this measurement is 1.1 run.

  8. Significant improvements in Long Trace Profiler measurement performance

    SciTech Connect

    Takacs, P.Z.; Bresloff, C.J.

    1996-12-31

    Modifications made to the Long Trace Profiler (LTP II) system at the Advanced Photon Source at Argonne National Laboratory have significantly improved the accuracy and repeatability of the instrument. The use of a Dove prism in the reference beam path corrects for phasing problems between mechanical errors and thermally-induced system errors. A single reference correction now completely removes both error signals from the measured surface profile. The addition of a precision air conditioner keeps the temperature in the metrology enclosure constant to within {+-} 0.1 C over a 24 hour period and has significantly improved the stability and repeatability of the system. The authors illustrate the performance improvements with several sets of measurements. The improved environmental control has reduced thermal drift error to about 0.75 microradian RMS over a 7.5 hour time period. Measurements made in the forward scan direction and the reverse scan direction differ by only about 0.5 microradian RMS over a 500 mm trace length. They are now able to put 1-sigma error bar of 0.3 microradian on an average of 10 slope profile measurements over a 500 mm long trace length, and they are now able to put a 0.2 microradian error bar on an average of 10 measurements over a 200 mm trace length. The corresponding 1-sigma height error bar for this measurement is 1.1 nm.

  9. Sonocrystallization yields monoclinic paracetamol with significantly improved compaction behavior.

    PubMed

    Bučar, Dejan-Krešimir; Elliott, James A; Eddleston, Mark D; Cockcroft, Jeremy K; Jones, William

    2015-01-01

    Ultrasound-assisted crystallization (sonocrystallization) was used to prepare a mixture of nano- and micrometer-sized crystals of the monoclinic form of paracetamol-a widely used analgesic known for its particularly problematic mechanical behavior under compression (i.e. poor tabletability). The nano- and micrometer-sized crystals yielded a powder which exhibits elastic moduli and bulk cohesions that are significantly higher than those observed in samples consisting of macrometer-sized crystals, thus leading to enhanced tabletability without the use of excipients, particle coating, salt, or cocrystal formation. Experimental compaction and finite element analysis were utilized to rationalize the significantly improved compaction behavior of the monoclinic form of paracetamol. PMID:25370777

  10. Prediction of Visual Acuity from Wavefront Aberrations

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B. (Inventor); Ahumada, Albert J. (Inventor)

    2013-01-01

    A method for generating a visual acuity metric, based on wavefront aberrations (WFAs), associated with a test subject and representing classes of imperfections, such as defocus, astigmatism, coma and spherical aberrations, of the subject's visual system. The metric allows choices of different image template, can predict acuity for different target probabilities, can incorporate different and possibly subject-specific neural transfer functions, can predict acuity for different subject templates, and incorporates a model of the optotype identification task.

  11. An improved optical identity authentication system with significant output images

    NASA Astrophysics Data System (ADS)

    Yuan, Sheng; Liu, Ming-tang; Yao, Shu-xia; Xin, Yan-hui

    2012-06-01

    An improved method for optical identity authentication system with significant output images is proposed. In this method, a predefined image is digitally encoded into two phase-masks relating to a fixed phase-mask, and this fixed phase-mask acts as a lock to the system. When the two phase-masks, serving as the key, are presented to the system, the predefined image is generated at the output. In addition to simple verification, our method is capable of identifying the type of input phase-mask, and the duties of identity verification and recognition are separated and, respectively, assigned to the amplitude and phase of the output image. Numerical simulation results show that our proposed method is feasible and the output image with better image quality can be obtained.

  12. Functional Visual Acuity of Early Presbyopia

    PubMed Central

    Watanabe, Kazuhiro; Shigeno, Yuta; Saiki, Megumi; Torii, Hidemasa; Kaido, Minako; Tsubota, Kazuo

    2016-01-01

    Purpose To evaluate visual function in patients with early presbyopia using the functional visual acuity (FVA) test. Methods This study included 27 eyes of 27 healthy older volunteers (mean age, 44.1 ± 2.6 years) and 14 eyes of 14 healthy young volunteers (mean age, 28.4±4.8 years). The distance-corrected visual acuity (DCVA), distance-corrected near VA (DCNVA), subjective amplitude of accommodation (AA), and distance and near pupillary diameters were measured. The distance FVA and distance-corrected near FVA (DCNFVA) were measured using the FVA Measurement System. The standard Schirmer test and standard tear break-up time measurement also were performed. Results The logarithm of the minimum angle of resolution (logMAR) DCVA was better than 0 in all subjects. The percentages of subjects with logMAR DCNVA below 0 was significantly lower in the presbyopia group than in the young group. The DCNFVA in the presbyopia group was significantly (P < 0.001) poorer than the DCNVA in that group. Significant linear negative correlations were seen between the DCNVA and AA (r = -0.507, P < 0.001) and the DCNFVA and AA (r = -0.681, P < 0.001) in the older subjects. Stepwise regression analysis showed that only the AA was a significant factor predictive of the DCNFVA in the presbyopia group. Tear function parameters were not adopted in the regression model. Conclusions Measurement of the DCNFVA can detect decreased AA in early presbyopia better than measurement of the conventional near VA. The DCNFVA is a good index for early presbyopia. PMID:26959362

  13. Warfarin improves neuropathy in monoclonal gammopathy of undetermined significance.

    PubMed

    Henry Gomez, Teny; Holkova, Beata; Noreika, Danielle; Del Fabbro, Egidio

    2016-01-01

    We report a case of a 60-year-old man who was referred to a palliative care clinic with monoclonal gammopathy of undetermined significance (MGUS)-associated neuropathy, responding to a therapeutic trial of warfarin. Electromyography showed distal symmetric sensory axonal neuropathy. The patient reported having had improvement of his neuropathic symptoms while taking warfarin postoperatively for thromboprophylaxis 1 year prior, and recurrence of his symptoms after the warfarin was discontinued. The patient was rechallenged with a trial of warfarin, targeting an international normalised ratio of 1.5-2.0. His pain scores decreased from 5/10 to 3/10 at 1 month and symptom improvement was maintained through 24 months of follow-up. Warfarin had a remarkable impact on our patient's symptoms and quality of life. The mechanisms mediating the symptomatic benefit with warfarin are unclear; however, a placebo effect is unlikely. Further studies may help guide the use of warfarin for MGUS-associated neuropathy. PMID:27317760

  14. The Relationship between OCT-measured Central Retinal Thickness and Visual Acuity in Diabetic Macular Edema

    PubMed Central

    2008-01-01

    Objective To compare optical coherence tomography (OCT)-measured retinal thickness and visual acuity in eyes with diabetic macular edema (DME) both before and after macular laser photocoagulation. Design Cross-sectional and longitudinal study. Participants 210 subjects (251 eyes) with DME enrolled in a randomized clinical trial of laser techniques. Methods Retinal thickness was measured with OCT and visual acuity was measured with the electronic-ETDRS procedure. Main Outcome Measures OCT-measured center point thickness and visual acuity Results The correlation coefficients for visual acuity versus OCT center point thickness were 0.52 at baseline and 0.49, 0.36, and 0.38 at 3.5, 8, and 12 months post-laser photocoagulation. The slope of the best fit line to the baseline data was approximately 4.4 letters (95% C.I.: 3.5, 5.3) better visual acuity for every 100 microns decrease in center point thickness at baseline with no important difference at follow-up visits. Approximately one-third of the variation in visual acuity could be predicted by a linear regression model that incorporated OCT center point thickness, age, hemoglobin A1C, and severity of fluorescein leakage in the center and inner subfields. The correlation between change in visual acuity and change in OCT center point thickening 3.5 months after laser treatment was 0.44 with no important difference at the other follow-up times. A subset of eyes showed paradoxical improvements in visual acuity with increased center point thickening (7–17% at the three time points) or paradoxical worsening of visual acuity with a decrease in center point thickening (18%–26% at the three time points). Conclusions There is modest correlation between OCT-measured center point thickness and visual acuity, and modest correlation of changes in retinal thickening and visual acuity following focal laser treatment for DME. However, a wide range of visual acuity may be observed for a given degree of retinal edema and paradoxical

  15. Ceramic Composite Intermediate Temperature Stress-Rupture Properties Improved Significantly

    NASA Technical Reports Server (NTRS)

    Morscher, Gregory N.; Hurst, Janet B.

    2002-01-01

    Silicon carbide (SiC) composites are considered to be potential materials for future aircraft engine parts such as combustor liners. It is envisioned that on the hot side (inner surface) of the combustor liner, composites will have to withstand temperatures in excess of 1200 C for thousands of hours in oxidizing environments. This is a severe condition; however, an equally severe, if not more detrimental, condition exists on the cold side (outer surface) of the combustor liner. Here, the temperatures are expected to be on the order of 800 to 1000 C under high tensile stress because of thermal gradients and attachment of the combustor liner to the engine frame (the hot side will be under compressive stress, a less severe stress-state for ceramics). Since these composites are not oxides, they oxidize. The worst form of oxidation for strength reduction occurs at these intermediate temperatures, where the boron nitride (BN) interphase oxidizes first, which causes the formation of a glass layer that strongly bonds the fibers to the matrix. When the fibers strongly bond to the matrix or to one another, the composite loses toughness and strength and becomes brittle. To increase the intermediate temperature stress-rupture properties, researchers must modify the BN interphase. With the support of the Ultra-Efficient Engine Technology (UEET) Program, significant improvements were made as state-of-the-art SiC/SiC composites were developed during the Enabling Propulsion Materials (EPM) program. Three approaches were found to improve the intermediate-temperature stress-rupture properties: fiber-spreading, high-temperature silicon- (Si) doped boron nitride (BN), and outside-debonding BN.

  16. A Comparison of Patched HOTV Visual Acuity and Photoscreening

    ERIC Educational Resources Information Center

    Leman, Rachel; Clausen, Michelle M.; Bates, Janice; Stark, Lee; Arnold, Koni K.; Arnold, Robert W.

    2006-01-01

    Early detection of significant vision problems in children is a high priority for pediatricians and school nurses. Routine vision screening is a necessary part of that detection and has traditionally involved acuity charts. However, photoscreening in which "red eye" is elicited to show whether each eye is focusing may outperform routine acuity…

  17. 38 CFR 4.76 - Visual acuity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer...

  18. 38 CFR 4.76 - Visual acuity.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer...

  19. 38 CFR 4.76 - Visual acuity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer...

  20. 38 CFR 4.76 - Visual acuity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer...

  1. 38 CFR 4.76 - Visual acuity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... distance and near vision using Snellen's test type or its equivalent. (b) Evaluation of visual acuity. (1) Evaluate central visual acuity on the basis of corrected distance vision with central fixation, even if a central scotoma is present. However, when the lens required to correct distance vision in the poorer...

  2. Final Visual Acuity Results in the Early Treatment for Retinopathy of Prematurity Study

    PubMed Central

    2014-01-01

    Objective To compare visual acuity at 6 years of age in eyes that received early treatment for high-risk prethreshold retinopathy of prematurity (ROP) with conventionally-managed eyes. Methods Infants with symmetrical, high-risk prethreshold ROP (N=317) had one eye randomized to earlier treatment at high-risk prethreshold disease and the other eye managed conventionally, treated if ROP progressed to threshold severity. For asymmetric cases (N=84), the high-risk prethreshold eye was randomized to either early treatment or conventional management. Main Outcome Measures ETDRS visual acuity measured at 6 years of age by masked testers. Retinal structure was assessed as a secondary outcome. Results Analysis of all subjects with high-risk prethreshold ROP showed no statistically significant benefit for early treatment (24.6% v. 29.0% unfavorable outcome, P=0.15). Analysis of 6-year visual acuity results according to the Type 1 and 2 clinical algorithm showed a benefit for Type 1 eyes (25.1% v. 32.8%, P=0.02) treated early, but not Type 2 eyes (23.6% v. 19.4%, P=0.37). Early treated eyes showed a significantly better structural outcome compared with conventionally managed eyes (8.9% v. 15.2% unfavorable outcome, P<0.001), with no greater risk of ocular complications. Conclusion Early treatment for Type 1 high-risk prethreshold eyes improved visual acuity outcomes at 6 years of age. Early treatment for Type 2 high-risk prethreshold eyes did not. Application to Clinical Practice Type 1 eyes, not Type 2 eyes should be treated early. These results are particularly important considering that 52 % of Type 2 high-risk prethreshold eyes underwent regression of ROP without requiring treatment. PMID:20385926

  3. Acuity of the Approximate Number System and Preschoolers' Quantitative Development

    ERIC Educational Resources Information Center

    van Marle, Kristy; Chu, Felicia W.; Li, Yaoran; Geary, David C.

    2014-01-01

    The study assessed the relations among acuity of the inherent approximate number system (ANS), performance on measures of symbolic quantitative knowledge, and mathematics achievement for a sample of 138 (64 boys) preschoolers. The Weber fraction (a measure of ANS acuity) and associated task accuracy were significantly correlated with mathematics…

  4. SHIFTX2: significantly improved protein chemical shift prediction.

    PubMed

    Han, Beomsoo; Liu, Yifeng; Ginzinger, Simon W; Wishart, David S

    2011-05-01

    A new computer program, called SHIFTX2, is described which is capable of rapidly and accurately calculating diamagnetic (1)H, (13)C and (15)N chemical shifts from protein coordinate data. Compared to its predecessor (SHIFTX) and to other existing protein chemical shift prediction programs, SHIFTX2 is substantially more accurate (up to 26% better by correlation coefficient with an RMS error that is up to 3.3× smaller) than the next best performing program. It also provides significantly more coverage (up to 10% more), is significantly faster (up to 8.5×) and capable of calculating a wider variety of backbone and side chain chemical shifts (up to 6×) than many other shift predictors. In particular, SHIFTX2 is able to attain correlation coefficients between experimentally observed and predicted backbone chemical shifts of 0.9800 ((15)N), 0.9959 ((13)Cα), 0.9992 ((13)Cβ), 0.9676 ((13)C'), 0.9714 ((1)HN), 0.9744 ((1)Hα) and RMS errors of 1.1169, 0.4412, 0.5163, 0.5330, 0.1711, and 0.1231 ppm, respectively. The correlation between SHIFTX2's predicted and observed side chain chemical shifts is 0.9787 ((13)C) and 0.9482 ((1)H) with RMS errors of 0.9754 and 0.1723 ppm, respectively. SHIFTX2 is able to achieve such a high level of accuracy by using a large, high quality database of training proteins (>190), by utilizing advanced machine learning techniques, by incorporating many more features (χ(2) and χ(3) angles, solvent accessibility, H-bond geometry, pH, temperature), and by combining sequence-based with structure-based chemical shift prediction techniques. With this substantial improvement in accuracy we believe that SHIFTX2 will open the door to many long-anticipated applications of chemical shift prediction to protein structure determination, refinement and validation. SHIFTX2 is available both as a standalone program and as a web server ( http://www.shiftx2.ca ). PMID:21448735

  5. Effects of distance and duration on vertical dynamic visual acuity in screening healthy adults and people with vestibular disorders

    PubMed Central

    Peters, Brian T.; Cohen, Helen S.; Sangi-Haghpeykar, Haleh; Bloomberg, Jacob J.

    2013-01-01

    Background Dynamic visual acuity (DVA) testing may be a useful, indirect indicator of vestibulo-ocular reflex function. Previous evidence shows that acuity for 2 m targets differs little between patients and normals using a 75 ms display duration and that healthy subjects do not differ in acuity when standing and walking while viewing a far target but they do differ when viewing a near target. Objective Improve the protocol of a screening tool by testing the hypothesis that healthy control subjects and patients and with unilateral peripheral vestibular weakness differ on DVA when viewing far targets while seated. Methods Controls and patients were tested while they were seated in a chair that oscillated vertically at 2 Hz. They viewed a computer screen 4 m away, while stationary and while moving, with viewing times of either 75 ms or 500 ms. Results The amount of change between static and dynamic conditions did not differ significantly between patients and controls for the 75 ms condition but controls had lower difference scores than patients when using the 500 ms duration. The ROC value was low, 0.68. Compared to historical data using the 75 ms duration at a distance of 2 m, subjects in both diagnostic groups had better visual acuity at the 75 ms/ 4 m distance. Conclusions These results suggest that using the longer duration is better for differentiating patients from healthy controls and they support previous evidence showing that near target viewing is more challenging. PMID:24447968

  6. How well do you see what you hear? The acuity of visual-to-auditory sensory substitution

    PubMed Central

    Haigh, Alastair; Brown, David J.; Meijer, Peter; Proulx, Michael J.

    2013-01-01

    Sensory substitution devices (SSDs) aim to compensate for the loss of a sensory modality, typically vision, by converting information from the lost modality into stimuli in a remaining modality. “The vOICe” is a visual-to-auditory SSD which encodes images taken by a camera worn by the user into “soundscapes” such that experienced users can extract information about their surroundings. Here we investigated how much detail was resolvable during the early induction stages by testing the acuity of blindfolded sighted, naïve vOICe users. Initial performance was well above chance. Participants who took the test twice as a form of minimal training showed a marked improvement on the second test. Acuity was slightly but not significantly impaired when participants wore a camera and judged letter orientations “live”. A positive correlation was found between participants' musical training and their acuity. The relationship between auditory expertise via musical training and the lack of a relationship with visual imagery, suggests that early use of a SSD draws primarily on the mechanisms of the sensory modality being used rather than the one being substituted. If vision is lost, audition represents the sensory channel of highest bandwidth of those remaining. The level of acuity found here, and the fact it was achieved with very little experience in sensory substitution by naïve users is promising. PMID:23785345

  7. Visual acuity and patient satisfaction at varied distances and lighting conditions after implantation of an aspheric diffractive multifocal one-piece intraocular lens

    PubMed Central

    Chang, Daniel H

    2016-01-01

    Purpose The aim of the study is to evaluate the visual acuity and patient satisfaction at varied distances under photopic and mesopic lighting conditions in patients bilaterally implanted with aspheric diffractive multifocal one-piece intraocular lenses. Methods In this retrospective–prospective study, 16 patients with a mean age of 66.2±9.2 years (range: 50–81 years) who had undergone bilateral phacoemulsification surgery with implantation of a Tecnis multifocal one-piece intraocular lens (ZMB00) were evaluated. Monocular and binocular uncorrected and distance-corrected visual acuities were measured at distance (20 ft), intermediate (70–80 cm), and near (35–40 cm) under photopic (85 cd/m2) and mesopic (3 cd/m2) lighting conditions and were compared using the paired t-test. All patients also completed a subjective questionnaire. Results At a mean follow-up of 9.5±3.9 months, distance, near, and intermediate visual acuity improved significantly from preoperative acuity. Under photopic and mesopic conditions, 93.8% and 62.5% of patients, respectively, had binocular uncorrected intermediate visual acuity of 20/40 or better, and 62.5% and 31.3% of patients had binocular uncorrected near visual acuity of 20/20 or better. All patients were satisfied with their overall vision without using glasses and/or contact lenses when compared with before surgery. A total of 87.5% of patients reported no glare and 68.8% of patients reported no halos around lights at night. Conclusion Tecnis multifocal one-piece intraocular lenses provide good distance, intermediate, and near visual acuity under photopic as well as mesopic lighting conditions. High levels of spectacle independence with low levels of photic phenomenon were achieved, resulting in excellent patient satisfaction. PMID:27536061

  8. Tactile Spatial Acuity in Childhood: Effects of Age and Fingertip Size

    PubMed Central

    Peters, Ryan M.; Goldreich, Daniel

    2013-01-01

    Tactile acuity is known to decline with age in adults, possibly as the result of receptor loss, but less is understood about how tactile acuity changes during childhood. Previous research from our laboratory has shown that fingertip size influences tactile spatial acuity in young adults: those with larger fingers tend to have poorer acuity, possibly because mechanoreceptors are more sparsely distributed in larger fingers. We hypothesized that a similar relationship would hold among children. If so, children’s tactile spatial acuity might be expected to worsen as their fingertips grow. However, concomitant CNS maturation might result in more efficient perceptual processing, counteracting the effect of fingertip growth on tactile acuity. To investigate, we conducted a cross-sectional study, testing 116 participants ranging in age from 6 to 16 years on a precision-controlled tactile grating orientation task. We measured each participant's grating orientation threshold on the dominant index finger, along with physical properties of the fingertip: surface area, volume, sweat pore spacing, and temperature. We found that, as in adults, children with larger fingertips (at a given age) had significantly poorer acuity, yet paradoxically acuity did not worsen significantly with age. We propose that finger growth during development results in a gradual decline in innervation density as receptive fields reposition to cover an expanding skin surface. At the same time, central maturation presumably enhances perceptual processing. PMID:24454612

  9. An investigation of the relation between sibilant production and somatosensory and auditory acuity

    PubMed Central

    Ghosh, Satrajit S.; Matthies, Melanie L.; Maas, Edwin; Hanson, Alexandra; Tiede, Mark; Ménard, Lucie; Guenther, Frank H.; Lane, Harlan; Perkell, Joseph S.

    2010-01-01

    The relation between auditory acuity, somatosensory acuity and the magnitude of produced sibilant contrast was investigated with data from 18 participants. To measure auditory acuity, stimuli from a synthetic sibilant continuum ([s]-[ʃ]) were used in a four-interval, two-alternative forced choice adaptive-staircase discrimination task. To measure somatosensory acuity, small plastic domes with grooves of different spacing were pressed against each participant’s tongue tip and the participant was asked to identify one of four possible orientations of the grooves. Sibilant contrast magnitudes were estimated from productions of the words ‘said,’ ‘shed,’ ‘sid,’ and ‘shid’. Multiple linear regression revealed a significant relation indicating that a combination of somatosensory and auditory acuity measures predicts produced acoustic contrast. When the participants were divided into high- and low-acuity groups based on their median somatosensory and auditory acuity measures, separate ANOVA analyses with sibilant contrast as the dependent variable yielded a significant main effect for each acuity group. These results provide evidence that sibilant productions have auditory as well as somatosensory goals and are consistent with prior results and the theoretical framework underlying the DIVA model of speech production. PMID:21110603

  10. Acuity assessment of non-verbal infants and children: clinical experience with the acuity card procedure.

    PubMed

    Mohn, G; van Hof-van Duin, J; Fetter, W P; de Groot, L; Hage, M

    1988-04-01

    The acuity card procedure was used to assess the visual acuity of 510 neurologically normal and abnormal infants and children. Acuity estimates were obtained for 93 per cent of 842 binocular and 279 monocular tests. The observed development of binocular acuity of normal fullterm and preterm infants agreed well with previous reports using the traditional forced-choice preferential looking technique. Monocular tests seemed to support earlier suggestions that grating acuity may be relatively insensitive to strabismic amblyopia. Infants at risk of later neurological deficits but developing normally had only a slight delay in development of acuity, but there was a high incidence of acuity deficits (54 per cent) among those with severe neurological defects. The great majority of a group of multiply handicapped children had low acuity for age. Repeat tests showed a high degree of test-retest consistency. The acuity card procedure was a successful and useful method for assessing the acuity of infants and children who cannot be tested with standard ophthalmological methods. PMID:3384203

  11. Visual acuity and magnification devices in dentistry.

    PubMed

    Perrin, Philippe; Eichenberger, Martina; Neuhaus, Klaus W; Lussi, Adrian

    2016-01-01

    This review discusses visual acuity in dentistry and the influence of optical aids. Studies based on objective visual tests at a dental working distance were included. These studies show dramatic individual variation independent of the dentists’ age. The limitations due to presbyopia begin at an age of 40 years. Dental professionals should have their near vision tested regularly. Visual deficiencies can be compensated with magnification aids. It is important to differentiate between Galilean and Keplerian loupes. The lightweight Galilean loupes allow an almost straight posture and offer improved ergonomics. Younger dentists profit more from the ergonomic aspects, while dentists over the age of 40 can compensate their age-related visual deficiencies when using this type of loupe. Keplerian loupes, with their superior optical construction, improve the visual performance for dentists of all age groups. The optical advantages come at the cost of ergonomic constraints due to the weight of these loupes. The microscope is highly superior visually and ergonomically, and it is indispensable for the visual control of endodontic treatments. PMID:27023468

  12. Significant improvement in IR surface-temperature measurements

    SciTech Connect

    Briles, S.D.; Bennett, G.A.; Larkin, T.H.; Worcester, P.

    1989-06-01

    Obtaining infrared (IR) surface-temperature measurements of miniature square targets on the order of 1.6 mm with a spatial resolution of 15 ..mu..m has recently become possible using the Barnes Engineering Computherm System, but the accuracy and precision of the measurements have been limited. The objective of this work is to provide a calibration procedure that will improve by a factor of 8 the accuracy and precision of the two-dimensional temperature measurement. The IR microscope detects energy emitted by the target and displays it as a radiance image. Heating the target to two known temperatures permits calculation of the target emissivity using the radiances at each pixel in the two-dimensional field. An error is induced in the emissivity calculation by substituting the thermal-well temperature for the known target surface temperature. At the same time, the radiance image is distorted by two functions that affect the measurement accuracy. The precision of the instrument is altered by a random noise field function. The noise functions were investigated to determine whether they were added to or multiplied by the radiance equation. A plot of image-radiance means shows the same trends as the added noise functions suggested by the prediction. Correction of the induced distortions improved the accuracy noticeably. Further improvement in the accuracy is accomplished by using a syringe thermocouple to measure the actual surface temperatures used for the emissivity calculations. Investigation of the random noise field shows that it is zero-mean and Gaussian in nature. We can therefore average images over time to improve the precision. 9 refs., 12 figs., 1 tab.

  13. Effect of yellow filter on visual acuity and contrast sensitivity under glare condition among different age groups.

    PubMed

    Mahjoob, Monireh; Heydarian, Samira; Koochi, Somayyeh

    2016-08-01

    The aim of this study is to investigate the effect of yellow filter on visual acuity and contrast sensitivity under glare condition for various ages. A total of 60 subjects, aged 5-60 years, with no ocular pathology and no previous surgery were assessed in this cross-sectional study. We divided subjects into six subgroups according to their ages, and the number of subjects in each group was 10: group 1, aged 5-10 years; group 2, aged 11-20 years; group 3, aged 21-30 years; group 4, aged 31-40 years; group 5, aged 41-50 years; and group 6, aged 51-60 years. Snellen visual acuity and Pelli Robson contrast sensitivity with and without glare and with the use of yellow filter under glare condition were determined. Data analysis was carried out using SPSS, version 20. Our results showed a significant reduction in contrast sensitivity under glare condition in all age groups (p = 0.000), which improved significantly with the use of yellow filter (p = 0.000). Although when data in different age groups were analyzed separately, this improvement was only significant in older subjects, aged 51-60 years (p = 0.007). No significant difference was found between Snellen visual acuity with and without glare (p = 0.083), and also we found no yellow filter effect on visual acuity under glare condition. We conclude that yellow filter, which absorbs short wavelength, may provide significant contrast sensitivity benefits for individuals and influences older subjects more than younger ones. PMID:26613932

  14. Strong tilt illusions always reduce orientation acuity.

    PubMed

    Solomon, Joshua A; Morgan, Michael J

    2009-03-01

    The apparent spatial orientation of an object can differ from its physical orientation when differently oriented objects surround it. This is the "tilt illusion". Previously [Solomon, J. A., & Morgan, M. J. (2006). Stochastic re-calibration: Contextual effects on perceived tilt. Proceedings of the Royal Society of London. Series B, Biological Sciences, 273, 2681-2686], we reported a loss of orientation acuity whenever a large physical tilt was required to compensate for the tilt illusion and make a target appear horizontal. Since all of those targets appeared to be at least approximately horizontal, we concluded that orientation acuity was not wholly determined by the target's apparent orientation. In the present study, we used oblique (i.e. neither horizontal nor vertical) reference orientations to more directly examine the effect of perceived orientation on orientation acuity. The results show that when surround and reference were parallel, there was no tilt illusion and acuity was high. Acuity suffered whenever the tilt illusion caused a large discrepancy between the target's physical and perceived tilts. Since this was true even for tilted references, context-induced acuity loss cannot be simply an "oblique effect" of the target's physical orientation. PMID:19268684

  15. Creating a Middle Grades Environment that Significantly Improves Student Achievement

    ERIC Educational Resources Information Center

    L'Esperance, Mark E.; Lenker, Ethan; Bullock, Ann; Lockamy, Becky; Mason, Cathy

    2013-01-01

    This article offers an overview of the framework that Sampson County Public Schools (North Carolina) used to critically reflect on the current state of their middle grades schools. The article also highlights the changes that resulted from the district-wide analysis and the ways in which these changes led to a significant increase in the academic…

  16. Accuracy of pitch matching significantly improved by live voice model.

    PubMed

    Granot, Roni Y; Israel-Kolatt, Rona; Gilboa, Avi; Kolatt, Tsafrir

    2013-05-01

    Singing is, undoubtedly, the most fundamental expression of our musical capacity, yet an estimated 10-15% of Western population sings "out-of-tune (OOT)." Previous research in children and adults suggests, albeit inconsistently, that imitating a human voice can improve pitch matching. In the present study, we focus on the potentially beneficial effects of the human voice and especially the live human voice. Eighteen participants varying in their singing abilities were required to imitate in singing a set of nine ascending and descending intervals presented to them in five different randomized blocked conditions: live piano, recorded piano, live voice using optimal voice production, recorded voice using optimal voice production, and recorded voice using artificial forced voice production. Pitch and interval matching in singing were much more accurate when participants repeated sung intervals as compared with intervals played to them on the piano. The advantage of the vocal over the piano stimuli was robust and emerged clearly regardless of whether piano tones were played live and in full view or were presented via recording. Live vocal stimuli elicited higher accuracy than recorded vocal stimuli, especially when the recorded vocal stimuli were produced in a forced vocal production. Remarkably, even those who would be considered OOT singers on the basis of their performance when repeating piano tones were able to pitch match live vocal sounds, with deviations well within the range of what is considered accurate singing (M=46.0, standard deviation=39.2 cents). In fact, those participants who were most OOT gained the most from the live voice model. Results are discussed in light of the dual auditory-motor encoding of pitch analogous to that found in speech. PMID:23528675

  17. Low Dose Vaporized Cannabis Significantly Improves Neuropathic Pain

    PubMed Central

    Wilsey, Barth; Marcotte, Thomas D.; Deutsch, Reena; Gouaux, Ben; Sakai, Staci; Donaghe, Haylee

    2013-01-01

    We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling either medium dose (3.53%), low dose (1.29%), or placebo cannabis with the primary outcome being VAS pain intensity. Psychoactive side-effects, and neuropsychological performance were also evaluated. Mixed effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the two active dose groups’ results (p>0.7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo vs. low dose, 2.9 for placebo vs. medium dose, and 25 for medium vs. low dose. As these NNT are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being, for all intents and purposes, as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well-tolerated, and neuropsychological effects were of limited duration and readily reversible within 1–2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. PMID:23237736

  18. Direct ChIP-Seq significance analysis improves target prediction

    PubMed Central

    2015-01-01

    Background Chromatin immunoprecipitation followed by sequencing of protein-bound DNA fragments (ChIP-Seq) is an effective high-throughput methodology for the identification of context specific DNA fragments that are bound by specific proteins in vivo. Despite significant progress in the bioinformatics analysis of this genome-scale data, a number of challenges remain as technology-dependent biases, including variable target accessibility and mappability, sequence-dependent variability, and non-specific binding affinity must be accounted for. Results and discussion We introduce a nonparametric method for scoring consensus regions of aligned immunoprecipitated DNA fragments when appropriate control experiments are available. Our method uses local models for null binding; these are necessary because binding prediction scores based on global models alone fail to properly account for specialized features of genomic regions and chance pull downs of specific DNA fragments, thus disproportionally rewarding some genomic regions and decreasing prediction accuracy. We make no assumptions about the structure or amplitude of bound peaks, yet we show that our method outperforms leading methods developed using either global or local null hypothesis models for random binding. We test prediction performance by comparing analyses of ChIP-seq, ChIP-chip, motif-based binding-site prediction, and shRNA assays, showing high reproducibility, binding-site enrichment in predicted target regions, and functional regulation of predicted targets. Conclusions Given appropriate controls, a direct nonparametric method for identifying transcription-factor targets from ChIP-Seq assays may lead to both higher sensitivity and higher specificity, and should be preferred or used in conjunction with methods that use parametric models for null binding. PMID:26040656

  19. Evaluation of visual acuity with Gen 3 night vision goggles

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur; Kaiser, Mary K.

    1994-01-01

    Using laboratory simulations, visual performance was measured at luminance and night vision imaging system (NVIS) radiance levels typically encountered in the natural nocturnal environment. Comparisons were made between visual performance with unaided vision and that observed with subjects using image intensification. An Amplified Night Vision Imaging System (ANVIS6) binocular image intensifier was used. Light levels available in the experiments (using video display technology and filters) were matched to those of reflecting objects illuminated by representative night-sky conditions (e.g., full moon, starlight). Results show that as expected, the precipitous decline in foveal acuity experienced with decreasing mesopic luminance levels is effectively shifted to much lower light levels by use of an image intensification system. The benefits of intensification are most pronounced foveally, but still observable at 20 deg eccentricity. Binocularity provides a small improvement in visual acuity under both intensified and unintensified conditions.

  20. Potential acuity meter for predicting visual acuity after Nd:YAG posterior capsulotomy

    SciTech Connect

    Smiddy, W.E.; Radulovic, D.; Yeo, J.H.; Stark, W.J.; Maumenee, A.E.

    1986-03-01

    We studied 30 patients with opacifications of the posterior capsule to determine if the potential acuity meter (PAM) could accurately predict final visual outcome after Nd:YAG discussion. The final visual acuity was within one line of the PAM prediction in 22 of 30 patients (73%), better by two or more lines in seven patients (23%), and worse in one patient (4%) by two lines. Although in thicker capsules the final acuity was occasionally better than the PAM prediction, the rates of false negative and false positive predictions were very low. Mild cystoid macular edema (3 patients), age-related macular degeneration (3 patients), intraocular lens status, and level of initial acuity did not diminish PAM accuracy. The PAM effectively predicts final visual acuity after YAG posterior capsulotomy, when used in a patient, unhurried manner.

  1. Relationship among fMRI, contrast sensitivity and visual acuity.

    PubMed

    Leguire, L E; Algaze, A; Kashou, N H; Lewis, J; Rogers, G L; Roberts, C

    2011-01-01

    The purpose of this study was to ascertain whether visual acuity or contrast sensitivity function (CSF) is proportional to visual cortical function based on fMRI volume and level of activation or Z-score. Forced choice procedures were utilized to measure the monocular log minimal angle of resolution (logMAR) visual acuity and CSF. The CSF data were collapsed into a single index by the use of weighted mean contrast sensitivity (WMCS), being defined as the mean of the products of each spatial frequency multiplied by its corresponding contrast sensitivity. fMRI data had been obtained with a 1.5 T GE Signa scanner with visual stimuli including 1.0 and 2.0 c/deg vertical sinusoidal gratings. Subjects consisted of eight normal adults and five amblyopic patients, with the amblyopic subjects added to gauge whether the outcome was due to a restricted range of scores or the small number of study participants. In normal subjects, the fMRI volume and level of activation exhibited no statistically significant correlation with visual acuity at P<0.05. Statistically significant correlations were obtained between WMCS and fMRI volume (R=0.765, P=0.027) and fMRI level of activation (R=0.645, P=0.007), with right eye stimulation using the 1.0 c/deg grating. On the whole, statistically significant correlations between WMCS and fMRI parameters were maintained when subject age was held constant and when data from the five amblyopic subjects were included to expand the range of values and increase the number of data sets for analysis. fMRI volume and Z-score were more closely associated with the CSF, as defined by WMCS, than visual acuity. The results suggest that the CSF reflects the underlying visual cortical cells responsible for fMRI volume and the level of activation. PMID:21035430

  2. The Effect of 3D Visual Simulator on Children’s Visual Acuity - A Pilot Study Comparing Two Different Modalities

    PubMed Central

    Ide, Takeshi; Ishikawa, Mariko; Tsubota, Kazuo; Miyao, Masaru

    2013-01-01

    Purpose : To evaluate the efficacy of two non-surgical interventions of vision improvement in children. Methods : A prospective, randomized, pilot study to compare fogging method and the use of head mounted 3D display. Subjects were children, between 5 to 15 years old, with normal best corrected visual acuity (BCVA) and up to -3D myopia. Subjects played a video game as near point work, and received one of the two methods of treatments. Measurements of uncorrected far visual acuity (UCVA), refraction with autorefractometer, and subjective accommodative amplitude were taken 3 times, at the baseline, after the near work, and after the treatment. Results : Both methods applied after near work, improved UCVA. Head mounted 3D display group showed significant improvement in UCVA and resulted in better UCVA than baseline. Fogging group showed improvement in subjective accommodative amplitude. While 3D display group did not show change in the refraction, fogging group’s myopic refraction showed significant increase indicating the eyes showed myopic change of eyes after near work and treatment. Discussion : Despite our lack of clear knowledge in the mechanisms, both methods improved UCVA after the treatments. The improvement in UCVA was not correlated to measured refraction values. Conclusion : UCVA after near work can be improved by repeating near and distant accommodation by fogging and 3D image viewing, although at the different degrees. Further investigation on mechanisms of improvements and their clinical significance are warranted. PMID:24222810

  3. Effects of Horizontal Acceleration on Human Visual Acuity and Stereopsis

    PubMed Central

    Horng, Chi-Ting; Hsieh, Yih-Shou; Tsai, Ming-Ling; Chang, Wei-Kang; Yang, Tzu-Hung; Yauan, Chien-Han; Wang, Chih-Hung; Kuo, Wu-Hsien; Wu, Yi-Chang

    2015-01-01

    The effect of horizontal acceleration on human visual acuity and stereopsis is demonstrated in this study. Twenty participants (mean age 22.6 years) were enrolled in the experiment. Acceleration from two different directions was performed at the Taiwan High-Speed Rail Laboratory. Gx and Gy (< and >0.1 g) were produced on an accelerating platform where the subjects stood. The visual acuity and stereopsis of the right eye were measured before and during the acceleration. Acceleration <0.1 g in the X- or Y-axis did not affect dynamic vision and stereopsis. Vision decreased (mean from 0.02 logMAR to 0.25 logMAR) and stereopsis declined significantly (mean from 40 s to 60.2 s of arc) when Gx > 0.1 g. Visual acuity worsened (mean from 0.02 logMAR to 0.19 logMAR) and poor stereopsis was noted (mean from 40 s to 50.2 s of arc) when Gy > 0.1 g. The effect of acceleration from the X-axis on the visual system was higher than that from the Y-axis. During acceleration, most subjects complained of ocular strain when reading. To our knowledge, this study is the first to report the exact levels of visual function loss during Gx and Gy. PMID:25607601

  4. Effects of horizontal acceleration on human visual acuity and stereopsis.

    PubMed

    Horng, Chi-Ting; Hsieh, Yih-Shou; Tsai, Ming-Ling; Chang, Wei-Kang; Yang, Tzu-Hung; Yauan, Chien-Han; Wang, Chih-Hung; Kuo, Wu-Hsien; Wu, Yi-Chang

    2015-01-01

    The effect of horizontal acceleration on human visual acuity and stereopsis is demonstrated in this study. Twenty participants (mean age 22.6 years) were enrolled in the experiment. Acceleration from two different directions was performed at the Taiwan High-Speed Rail Laboratory. Gx and Gy (< and >0.1 g) were produced on an accelerating platform where the subjects stood. The visual acuity and stereopsis of the right eye were measured before and during the acceleration. Acceleration <0.1 g in the X- or Y-axis did not affect dynamic vision and stereopsis. Vision decreased (mean from 0.02 logMAR to 0.25 logMAR) and stereopsis declined significantly (mean from 40 s to 60.2 s of arc) when Gx > 0.1 g. Visual acuity worsened (mean from 0.02 logMAR to 0.19 logMAR) and poor stereopsis was noted (mean from 40 s to 50.2 s of arc) when Gy > 0.1 g. The effect of acceleration from the X-axis on the visual system was higher than that from the Y-axis. During acceleration, most subjects complained of ocular strain when reading. To our knowledge, this study is the first to report the exact levels of visual function loss during Gx and Gy. PMID:25607601

  5. Visual Acuity of Children: United States.

    ERIC Educational Resources Information Center

    Health Services and Mental Health Administration (DHEW), Bethesda, MD.

    National estimates based on the findings from the Health Examination Survey in 1963 to 1965 of uncorrected monocular and binocular visual-acuity levels of children were studied. A nationwide sample of 7,417 children was selected to represent the approximately 24 million noninstitutionalized American children between ages 6 and 11 years. Testing…

  6. Linkages of biomarkers of zinc with cognitive performance and taste acuity in adolescent girls.

    PubMed

    Chiplonkar, Shashi A; Kawade, Rama

    2014-06-01

    A cross-sectional study (n = 403) was conducted to examine the relationship of plasma zinc (PZ) and erythrocyte zinc (EZ) levels with cognitive performance and taste acuity for salt in Indian adolescent girls. PZ, EZ and hemoglobin were estimated in schoolgirls (10-16 years). Cognitive performance was assessed by simple-reaction-time (SRT), recognition-reaction-time (RRT), visual-memory, Raven's Progressive Matrices (RPM) test. Taste acuity was determined by recognition-thresholds-for-salt (RTS) using 10 different salt concentrations. Low PZ (<0.7 mg/l) and EZ (<8 µg/g of packed cells) were observed in 72% and 23.6% of girls, respectively. PZ and EZ were negatively associated with SRT (r = -0.41, -0.34), RRT (r = -0.49, -0.4), and positively with Memory (r = 0.43, 0.34) and RPM (r = 0.39, 0.31; p < 0.05) and remained significant after adjusting for socio-demographic factors and hemoglobin. RTS was impaired in 18.3% girls and significantly correlated with EZ (r = -0.31, p < 0.05). Zinc deficiency in adolescent girls was associated with poor cognition and taste function implying need for improving their dietary zinc intakes. PMID:24490852

  7. Recovery of Upper Extremity Sensorimotor System Acuity in Baseball Athletes After a Throwing-Fatigue Protocol

    PubMed Central

    Tripp, Brady L; Yochem, Eric M; Uhl, Timothy L

    2007-01-01

    Context: Research indicates that upper extremity fatigue hampers sensorimotor system acuity. However, no investigators have observed recovery of upper extremity acuity after fatigue. Objective: To observe recovery of active position reproduction acuity in overhead throwers after a throwing-fatigue protocol. Design: Single-session, repeated-measures design. Setting: University musculoskeletal laboratory. Patients or Other Participants: Sixteen healthy collegiate baseball players (age = 21.0 ± 1.6 years, height = 175.8 ± 10.2 cm, mass = 82.8 ± 4.3 kg). Intervention(s): Subjects threw a baseball with maximum velocity (every 5 seconds) from a single knee. Every 20 throws, subjects rated their upper extremity exertion on a Borg scale until reporting a level of more than 14. Main Outcome Measure(s): We used an electromagnetic tracking system to measure active multijoint position reproduction acuity at 5 intervals: prefatigue; immediately postfatigue; and after 4, 7, and 10 minutes of recovery. Blindfolded subjects reproduced their arm-cocked and ball-release positions. Dependent variables were 3-dimensional variable errors of scapulothoracic, glenohumeral, elbow, and wrist joints; endpoint (ie, hand) position error represented overall upper extremity acuity. The independent variable was time (measured prefatigue and at 4 postfatigue intervals). Results: Fatigue significantly affected acuity of scapulothoracic, glenohumeral, and elbow joints and endpoint error for both positions (P < .001). Fatigue significantly affected wrist acuity only for ball release (P < .001). For arm-cocked reproduction, each measure of acuity, except that of the glenohumeral joint, recovered by 7 minutes; for ball release, each measure of acuity recovered within 4 minutes (P > .05). Conclusions: The sensorimotor system deficits that we observed after fatigue recovered within 7 minutes in most upper extremity joints. Glenohumeral arm-cocked position reproduction acuity failed to recover within

  8. Water-Induced Finger Wrinkles Do Not Affect Touch Acuity or Dexterity in Handling Wet Objects

    PubMed Central

    Frenzel, Henning; Gross, Manfred; Lewin, Gary R.

    2014-01-01

    Human non-hairy (glabrous) skin of the fingers, palms and soles wrinkles after prolonged exposure to water. Wrinkling is a sympathetic nervous system-dependent process but little is known about the physiology and potential functions of water-induced skin wrinkling. Here we investigated the idea that wrinkling might improve handling of wet objects by measuring the performance of a large cohort of human subjects (n = 40) in a manual dexterity task. We also tested the idea that skin wrinkling has an impact on tactile acuity or vibrotactile sensation using two independent sensory tasks. We found that skin wrinkling did not improve dexterity in handling wet objects nor did it affect any aspect of touch sensitivity measured. Thus water-induced wrinkling appears to have no significant impact on tactile driven performance or dexterity in handling wet or dry objects. PMID:24416318

  9. Visual Acuity Testing: Feedback Affects Neither Outcome nor Reproducibility, but Leaves Participants Happier

    PubMed Central

    Bach, Michael; Schäfer, Kerstin

    2016-01-01

    Assessment of visual acuity is a well standardized procedure at least for expert opinions and clinical trials. It is often recommended not giving patients feedback on the correctness of their responses. As this viewpoint has not been quantitatively examined so far, we quantitatively assessed possible effects of feedback on visual acuity testing. In 40 normal participants we presented Landolt Cs in 8 orientations using the automated Freiburg Acuity Test (FrACT, acuity threshold was measured with an adaptive staircase procedure. In an ABCDDCBA scheme, trial-by-trial feedback was provided in 2 x 4 conditions: (A) no feedback, (B) acoustic signals indicating correctness, (C)visual indication of correct orientation, and (D) a combination of (B) and (C). After each run the participants judged comfort. Main outcome measures were absolute visual acuity (logMAR), its test-retest agreement (limits of agreement) and participants’ comfort estimates on a 5-step symmetric Likert scale. Feedback influenced acuity outcome significantly (p = 0.02), but with a tiny effect size: 0.02 logMAR poorer acuity for (D) compared to (A), even weaker effects for (B) and (C). Test-retest agreement was high (limits of agreement: ± 1.0 lines) and did not depend on feedback (p>0.5). The comfort ranking clearly differed, by 2 steps on the Likert scale: the condition (A)–no feedback–was on average “slightly uncomfortable”, the other three conditions were “slightly comfortable” (p<0.0001). Feedback affected neither reproducibility nor the acuity outcome to any relevant extent. The participants, however, reported markedly greater comfort with any kind of feedback. We conclude that systematic feedback (as implemented in FrACT) offers nothing but advantages for routine use. PMID:26824693

  10. Visual Acuity Testing: Feedback Affects Neither Outcome nor Reproducibility, but Leaves Participants Happier.

    PubMed

    Bach, Michael; Schäfer, Kerstin

    2016-01-01

    Assessment of visual acuity is a well standardized procedure at least for expert opinions and clinical trials. It is often recommended not giving patients feedback on the correctness of their responses. As this viewpoint has not been quantitatively examined so far, we quantitatively assessed possible effects of feedback on visual acuity testing. In 40 normal participants we presented Landolt Cs in 8 orientations using the automated Freiburg Acuity Test (FrACT, acuity threshold was measured with an adaptive staircase procedure. In an ABCDDCBA scheme, trial-by-trial feedback was provided in 2 x 4 conditions: (A) no feedback, (B) acoustic signals indicating correctness, (C)visual indication of correct orientation, and (D) a combination of (B) and (C). After each run the participants judged comfort. Main outcome measures were absolute visual acuity (logMAR), its test-retest agreement (limits of agreement) and participants' comfort estimates on a 5-step symmetric Likert scale. Feedback influenced acuity outcome significantly (p = 0.02), but with a tiny effect size: 0.02 logMAR poorer acuity for (D) compared to (A), even weaker effects for (B) and (C). Test-retest agreement was high (limits of agreement: ± 1.0 lines) and did not depend on feedback (p>0.5). The comfort ranking clearly differed, by 2 steps on the Likert scale: the condition (A)-no feedback-was on average "slightly uncomfortable", the other three conditions were "slightly comfortable" (p<0.0001). Feedback affected neither reproducibility nor the acuity outcome to any relevant extent. The participants, however, reported markedly greater comfort with any kind of feedback. We conclude that systematic feedback (as implemented in FrACT) offers nothing but advantages for routine use. PMID:26824693

  11. Crowding and visual acuity measured in adults using paediatric test letters, pictures and symbols.

    PubMed

    Lalor, Sarah J H; Formankiewicz, Monika A; Waugh, Sarah J

    2016-04-01

    Crowding refers to the degradation of visual acuity for target optotypes with, versus without, surrounding features. Crowding is important clinically, however the effect of target-flanker spacing on acuity for symbols and pictures, compared to letters, has not been investigated. Five adults with corrected-to-normal vision had visual acuity measured for modified single target versions of Kay Pictures, Lea Symbols, HOTV and Cambridge Crowding Cards, tests. Single optotypes were presented in isolation and with surrounding features placed 0-5 stroke-widths away. Visual acuity measured with Kay Picture optotypes is 0.13-0.19logMAR better than for other test optotypes and varies significantly across picture. The magnitude of crowding is strongest when the surrounding features abut, or are placed 1 stroke-width away from the target optotype. The slope of the psychometric function is steeper in the region just beyond maximum crowding. Crowding is strongest and the psychometric function steepest, with the Cambridge Crowding Cards arrangement, than when any single optotype is surrounded by a box. Estimates of crowding extent are less variable across test when expressed in units of stroke-width, than optotype-width. Crowding for single target presentations of letters, symbols and pictures used in paediatric visual acuity tests can be maximised and made more sensitive to change in visual acuity, by careful selection of optotype, by surrounding the target with similar flankers, and by using a closer target-flanker separation than half an optotype-width. PMID:26878696

  12. Variable acuity remote viewing system flight demonstration

    NASA Technical Reports Server (NTRS)

    Fisher, R. W.

    1983-01-01

    The Variable Acuity Remote Viewing System (VARVS), originally developed under contract to the Navy (ONR) as a laboratory brassboard, was modified for flight demonstration. The VARVS system was originally conceived as a technique which could circumvent the acuity/field of view/bandwidth tradeoffs that exists in remote viewing to provide a nearly eye limited display in both field of view (160 deg) and resolution (2 min arc) while utilizing conventional TV sensing, transmission, and display equipment. The modifications for flight demonstration consisted of modifying the sensor so it could be installed and flow in a Piper PA20 aircraft, equipped for remote control and modifying the display equipment so it could be integrated with the NASA Research RPB (RPRV) remote control cockpit.

  13. Acuity of mental representations of pitch.

    PubMed

    Janata, Petr

    2012-04-01

    Singing in one's mind or forming expectations about upcoming notes both require that mental images of one or more pitches will be generated. As with other musical abilities, the acuity with which such images are formed might be expected to vary across individuals and may depend on musical training. Results from several behavioral tasks involving intonation judgments indicate that multiple memory systems contribute to the formation of accurate mental images for pitch, and that the functionality of each is affected by musical training. Electrophysiological measures indicate that the ability to form accurate mental images is associated with greater engagement of auditory areas and associated error-detection circuitry when listeners imagine ascending scales and make intonation judgments about target notes. A view of auditory mental images is espoused in which unified mental image representations are distributed across multiple brain areas. Each brain area helps shape the acuity of the unified representation based on current behavioral demands and past experience. PMID:22524362

  14. 21 CFR 886.1150 - Visual acuity chart.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Visual acuity chart. 886.1150 Section 886.1150...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1150 Visual acuity chart. (a) Identification. A visual acuity chart is a device that is a chart, such as a Snellen chart with block letters...

  15. 21 CFR 886.1150 - Visual acuity chart.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Visual acuity chart. 886.1150 Section 886.1150...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1150 Visual acuity chart. (a) Identification. A visual acuity chart is a device that is a chart, such as a Snellen chart with block letters...

  16. 21 CFR 886.1150 - Visual acuity chart.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Visual acuity chart. 886.1150 Section 886.1150...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1150 Visual acuity chart. (a) Identification. A visual acuity chart is a device that is a chart, such as a Snellen chart with block letters...

  17. 21 CFR 886.1150 - Visual acuity chart.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Visual acuity chart. 886.1150 Section 886.1150...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1150 Visual acuity chart. (a) Identification. A visual acuity chart is a device that is a chart, such as a Snellen chart with block letters...

  18. 21 CFR 886.1150 - Visual acuity chart.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Visual acuity chart. 886.1150 Section 886.1150...) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1150 Visual acuity chart. (a) Identification. A visual acuity chart is a device that is a chart, such as a Snellen chart with block letters...

  19. The effects of lubricant eye drops on visual function as measured by the Inter-blink interval Visual Acuity Decay test

    PubMed Central

    Torkildsen, Gail

    2009-01-01

    Objective: The purpose of the current study was to evaluate the effects of two marketed ocular lubricants on the visual decay in dry eye patients using the Inter-blink interval Visual Acuity Decay (IVAD) test. Methods: This controlled, randomized, double-masked crossover study compared the effects of a polyethylene glycol/propylene glycol-based (PEG/PG) tear and a carboxymethylcellulose sodium (CMC)/glycerin tear on the visual acuity decay between blinks of dry eye patients. At visit 1 (Day 0), baseline IVAD measurements were recorded prior to instillation of a single drop of randomized study medication. IVAD testing was repeated at 15-, 45-, and 90-minutes post-instillation. Reading rate and functional blink rate were also evaluated. At the second visit (Day 7 ± 3), study procedures were repeated using crossover treatment. Results: Forty-eight (48) subjects with dry eye (61.1 ± 14.8 years old, 79.2% female, 95.8% white) completed the study. Treatment with the PEG/PG-based tear demonstrated statistically significantly longer time to one-line loss of best-corrected visual acuity (BCVA) as determined by the IVAD test at 90 minutes post-instillation compared to the CMC/glycerin tear (P = 0.0365). Measurements of median time at BCVA, reading rate, and functional blink rate were similar for both treatments. Both formulations were well tolerated in the population studied. Conclusions: Treatment with the PEG/PG-based tear demonstrated statistically significant improved maintenance of visual acuity between blinks at 90 minutes post-instillation compared to the CMC/glycerin tear. This is the first study to demonstrate the ability of an artificial tear to extend visual acuity maintenance between blinks, as measured by the IVAD test. PMID:19789659

  20. Macular edema in Asian Indian premature infants with retinopathy of prematurity: Impact on visual acuity and refractive status after 1-year

    PubMed Central

    Vinekar, Anand; Mangalesh, Shwetha; Jayadev, Chaitra; Bauer, Noel; Munusamy, Sivakumar; Kemmanu, Vasudha; Kurian, Mathew; Mahendradas, Padmamalini; Avadhani, Kavitha; Shetty, Bhujang

    2015-01-01

    Purpose: To report the impact of transient, self-resolving, untreated “macular edema” detected on spectral domain optical coherence tomography in Asian Indian premature infants with retinopathy of prematurity (ROP) on visual acuity (VA) and refraction at 1-year of corrected age. Materials and Methods: Visual acuity and refraction of 11 infants with bilateral macular edema (Group A) was compared with gestational age-matched 16 infants with ROP without edema (Group B) and 17 preterms infants without ROP and without edema (Group C) at 3, 6, 9 and 12 months of corrected age using Teller Acuity Cards and cycloplegic retinoscopy. Sub-group analysis of the previously described pattern A and B macular edema was performed. Results: Visual acuity was lower in infants with macular edema compared with the other two control groups throughout the study period, but statistically significant only at 3 months. Visual improvement in these infants was highest between the 3rd and 6th month and plateaued by the end of the 1st year with acuity comparable to the other two groups. The edema cohort was more hyperopic compared to the other two groups between 3 and 12 months of age. Pattern A edema had worse VA compared to pattern B, although not statistically significant. Conclusion: Macular edema, although transient, caused reduced VA as early as 3 months of corrected age in Asian Indian premature infants weighing <2000 g at birth. The higher hyperopia in these infants is possibly due to visual disturbances caused at a critical time of fovealization. We hypothesize a recovery and feedback mechanism based on the principles of active emmetropization to explain our findings. PMID:26139806

  1. The influence of corrected visual acuity on visual attention and incidental learning in patients with multiple sclerosis.

    PubMed

    Davis, Andrew S; Hertza, Jeremy; Williams, Ronald N; Gupta, Ajay S; Ohly, Johann G

    2009-07-01

    Visual disturbance is one of the hallmarks of multiple sclerosis (MS), yet clinical neuropsychologists rarely quantitatively assess visual acuity using standardized and norm-referenced measures. This is a significant oversight because disturbances in visual acuity can have an obvious and profound impact on neuropsychological tests which rely upon visual attention and/or scanning. This study investigated the relationship between corrected visual acuity and a widely used measure of visual attention and incidental learning in a group of 35 patients with MS. Regression analysis indicated that corrected visual acuity accounted for 21.3% of the variance in a Coding subtest. The results suggest neuropsychologists and other health care providers should exercise caution in interpreting visually based tests for patients with MS and should assess visual acuity with standardized and norm-referenced measures. PMID:20183167

  2. Determine the effect of neck muscle fatigue on dynamic visual acuity in healthy young adults

    PubMed Central

    Al Saif, Amer A.; Al Senany, Samira

    2015-01-01

    [Purpose] The aim of this study was to determine whether neck muscle fatigue affects dynamic visual acuity in healthy young participants. [Subjects and Methods] This study was a double-blinded, prospective, randomized, controlled trial. Thirty healthy young subjects (ages 21 to 30 years) participated in the study. Participants were randomly divided into an experimental group (n=15) and a control group (n=15). The experimental group performed an exercise designed to induce neck muscle fatigue and the control group preformed non-fatiguing sham exercises. [Results] There were significant differences in mean dynamic visual acuity between the two groups (0.26±0.11 LogMar versus 0.003±0.02 LogMar). Subjects in the experimental group showed a significant decline in their dynamic visual acuity compared with the control group. Dynamic visual acuity strongly correlated with neck muscle fatigue (r = 0.79). No significant differences in joint position error were observed between the two groups and no significant correlations between joint position error and neck muscle fatigue were observed (r = 0.23). [Conclusion] The results of this study suggest that neck muscle fatigue negatively impacts dynamic visual acuity. Although not statistically significant, cervical spine proprioception as measured by the joint position error in the experimental group was diminished after fatigue. PMID:25642087

  3. Effect of Target Location on Dynamic Visual Acuity During Passive Horizontal Rotation

    NASA Technical Reports Server (NTRS)

    Appelbaum, Meghan; DeDios, Yiri; Kulecz, Walter; Peters, Brian; Wood, Scott

    2010-01-01

    The vestibulo-ocular reflex (VOR) generates eye rotation to compensate for potential retinal slip in the specific plane of head movement. Dynamic visual acuity (DVA) has been utilized as a functional measure of the VOR. The purpose of this study was to examine changes in accuracy and reaction time when performing a DVA task with targets offset from the plane of rotation, e.g. offset vertically during horizontal rotation. Visual acuity was measured in 12 healthy subjects as they moved a hand-held joystick to indicate the orientation of a computer-generated Landolt C "as quickly and accurately as possible." Acuity thresholds were established with optotypes presented centrally on a wall-mounted LCD screen at 1.3 m distance, first without motion (static condition) and then while oscillating at 0.8 Hz (DVA, peak velocity 60 deg/s). The effect of target location was then measured during horizontal rotation with the optotypes randomly presented in one of nine different locations on the screen (offset up to 10 deg). The optotype size (logMar 0, 0.2 or 0.4, corresponding to Snellen range 20/20 to 20/50) and presentation duration (150, 300 and 450 ms) were counter-balanced across five trials, each utilizing horizontal rotation at 0.8 Hz. Dynamic acuity was reduced relative to static acuity in 7 of 12 subjects by one step size. During the random target trials, both accuracy and reaction time improved proportional to optotype size. Accuracy and reaction time also improved between 150 ms and 300 ms presentation durations. The main finding was that both accuracy and reaction time varied as a function of target location, with greater performance decrements when acquiring vertical targets. We conclude that dynamic visual acuity varies with target location, with acuity optimized for targets in the plane of motion. Both reaction time and accuracy are functionally relevant DVA parameters of VOR function.

  4. Dynamic visual acuity testing for screening patients with vestibular impairments

    PubMed Central

    Peters, Brian T.; Mulavara, Ajitkumar P.; Cohen, Helen S.; Sangi-Haghpeykar, Haleh; Bloomberg, Jacob J.

    2013-01-01

    Dynamic visual acuity (DVA) may be a useful indicator of the function of the vestibulo-ocular reflex (VOR) but most DVA tests involve active head motion in the yaw plane. During gait the passive, vertical VOR may be more relevant and passive testing would be less likely to elicit compensatory strategies. The goal of this study was to determine if testing dynamic visual acuity during passive vertical motion of the subject would differentiate normal subjects from patients with known vestibular disorders. Subjects, normals and patients who had been diagnosed with either unilateral vestibular weaknesses or were post-acoustic neuroma resections, sat in a chair that could oscillate vertically with the head either free or constrained with a cervical orthosis. They viewed a computer screen 2 m away that showed Landholt C optotypes in one of 8 spatial configurations and which ranged in size from 0.4 to 1.0 logMAR. They were tested while the chair was stationary and while it was moving. Scores were worse for both groups during the dynamic condition compared to the static condition. In the dynamic condition patients’ scores were significantly worse than normals’ scores. Younger and older age groups differed slightly but significantly; the sample size was too small to examine age differences by decade. The data suggest that many well-compensated patients have dynamic visual acuity that is as good as age-matched normals. Results of ROC analyses were only moderate, indicating that the differences between patients and normals were not strong enough, under the conditions tested, for this test to be useful for screening people to determine if they have vestibular disorders. Modifications of the test paradigm may make it more useful for screening potential patients. PMID:23000614

  5. Dynamic visual acuity testing for screening patients with vestibular impairments.

    PubMed

    Peters, Brian T; Mulavara, Ajitkumar P; Cohen, Helen S; Sangi-Haghpeykar, Haleh; Bloomberg, Jacob J

    2012-01-01

    Dynamic visual acuity (DVA) may be a useful indicator of the function of the vestibulo-ocular reflex (VOR) but most DVA tests involve active head motion in the yaw plane. During gait the passive, vertical VOR may be more relevant and passive testing would be less likely to elicit compensatory strategies. The goal of this study was to determine if testing dynamic visual acuity during passive vertical motion of the subject would differentiate normal subjects from patients with known vestibular disorders. Subjects, normals and patients who had been diagnosed with either unilateral vestibular weaknesses or were post-acoustic neuroma resections, sat in a chair that could oscillate vertically with the head either free or constrained with a cervical orthosis. They viewed a computer screen 2 m away that showed Landholt C optotypes in one of 8 spatial configurations and which ranged in size from 0.4 to 1.0 logMAR. They were tested while the chair was stationary and while it was moving. Scores were worse for both groups during the dynamic condition compared to the static condition. In the dynamic condition patients' scores were significantly worse than normals' scores. Younger and older age groups differed slightly but significantly; the sample size was too small to examine age differences by decade. The data suggest that many well-compensated patients have dynamic visual acuity that is as good as age-matched normals. Results of ROC analyses were only moderate, indicating that the differences between patients and normals were not strong enough, under the conditions tested, for this test to be useful for screening people to determine if they have vestibular disorders. Modifications of the test paradigm may make it more useful for screening potential patients. PMID:23000614

  6. Modeling acuity for optotypes varying in complexity.

    PubMed

    Watson, Andrew B; Ahumada, Albert J

    2012-01-01

    Watson and Ahumada (2008) described a template model of visual acuity based on an ideal-observer limited by optical filtering, neural filtering, and noise. They computed predictions for selected optotypes and optical aberrations. Here we compare this model's predictions to acuity data for six human observers, each viewing seven different optotype sets, consisting of one set of Sloan letters and six sets of Chinese characters, differing in complexity (Zhang, Zhang, Xue, Liu, & Yu, 2007). Since optical aberrations for the six observers were unknown, we constructed 200 model observers using aberrations collected from 200 normal human eyes (Thibos, Hong, Bradley, & Cheng, 2002). For each condition (observer, optotype set, model observer) we estimated the model noise required to match the data. Expressed as efficiency, performance for Chinese characters was 1.4 to 2.7 times lower than for Sloan letters. Efficiency was weakly and inversely related to perimetric complexity of optotype set. We also compared confusion matrices for human and model observers. Correlations for off-diagonal elements ranged from 0.5 to 0.8 for different sets, and the average correlation for the template model was superior to a geometrical moment model with a comparable number of parameters (Liu, Klein, Xue, Zhang, & Yu, 2009). The template model performed well overall. Estimated psychometric function slopes matched the data, and noise estimates agreed roughly with those obtained independently from contrast sensitivity to Gabor targets. For optotypes of low complexity, the model accurately predicted relative performance. This suggests the model may be used to compare acuities measured with different sets of simple optotypes. PMID:23024356

  7. Functional Visual Acuity in Age-Related Macular Degeneration

    PubMed Central

    Tomita, Yohei; Nagai, Norihiro; Suzuki, Misa; Shinoda, Hajime; Uchida, Atsuro; Mochimaru, Hiroshi; Izumi-Nagai, Kanako; Sasaki, Mariko; Tsubota, Kazuo; Ozawa, Yoko

    2016-01-01

    ABSTRACT Purpose We evaluated whether a functional visual acuity (FVA) system can detect subtle changes in central visual acuity that reflect pathological findings associated with age-related macular degeneration (AMD). Methods Twenty-eight patients with unilateral AMD and logMAR monocular best corrected VA better than 0 in both eyes, as measured by conventional chart examination, were analyzed between November 2012 and April 2013. After measuring conventional VA, FVA, and contrast VA with best correction, routine eye examinations including spectral domain–optical coherence tomography were performed. Standard Schirmer test was performed, and corneal and lens densities were measured. Results The FVA score (p < 0.001) and visual maintenance ratio (p < 0.001) measured by the FVA system, contrast VA (p < 0. 01), and conventional VA (p < 0.01) were significantly worse in the AMD-affected eyes than in the fellow eyes. No significant differences were observed in the anterior segment conditions. Forward stepwise regression analysis demonstrated that the length of interdigitation zone disruption, as visualized by optical coherence tomography imaging, correlated with the FVA score (p < 0.01) but not with any other parameters investigated. Conclusions The FVA system detects subtle changes in best corrected VA in AMD-affected eyes and reflects interdigitation zone disruption, an anatomical change in the retina recorded by optical coherence tomography. Further studies are required to understand the value of the FVA system in detecting subtle changes in AMD. PMID:26583795

  8. Development of Proprioceptive Acuity in Typically Developing Children: Normative Data on Forearm Position Sense.

    PubMed

    Holst-Wolf, Jessica M; Yeh, I-Ling; Konczak, Jürgen

    2016-01-01

    This study mapped the development of proprioception in healthy, typically developing children by objectively measuring forearm position sense acuity. We assessed position sense acuity in a cross-sectional sample of 308 children (5-17 years old; M/F = 127/181) and a reference group of 26 healthy adults (18-25 years old; M/F = 12/14) using a body-scalable bimanual manipulandum that allowed forearm flexion/extension in the horizontal plane. The non-dominant forearm was passively displaced to one of three target positions. Then participants actively matched the target limb position with their dominant forearm. Each of three positions was matched five times. Position error (PE), calculated as the mean difference between the angular positions of the matching and reference arms, measured position sense bias or systematic error. The respective standard deviation of the differences between the match and reference arm angular positions (SDPdiff) indicated position sense precision or random error. The main results are as follows: First, systematic error, measured by PE, did not change significantly from early childhood to late adolescence (Median PE at 90° target: -2.85° in early childhood; -2.28° in adolescence; and 1.30° in adults). Second, response variability as measured by SDPdiff significantly decreased with age (Median SDPdiff at 90° target: 9.66° in early childhood; 5.30° in late adolescence; and 3.97° in adults). The data of this large cross-sectional sample of children document that proprioceptive development in typically developing children is characterized as an age-related improvement in precision, not as a development or change in bias. In other words, it is the reliability of the perceptual response that improves between early childhood and adulthood. This study provides normative data against which position sense acuity in pediatric patient populations can be compared. The underlying neurophysiological processes that could explain the observed

  9. Development of Proprioceptive Acuity in Typically Developing Children: Normative Data on Forearm Position Sense

    PubMed Central

    Holst-Wolf, Jessica M.; Yeh, I-Ling; Konczak, Jürgen

    2016-01-01

    This study mapped the development of proprioception in healthy, typically developing children by objectively measuring forearm position sense acuity. We assessed position sense acuity in a cross-sectional sample of 308 children (5–17 years old; M/F = 127/181) and a reference group of 26 healthy adults (18–25 years old; M/F = 12/14) using a body-scalable bimanual manipulandum that allowed forearm flexion/extension in the horizontal plane. The non-dominant forearm was passively displaced to one of three target positions. Then participants actively matched the target limb position with their dominant forearm. Each of three positions was matched five times. Position error (PE), calculated as the mean difference between the angular positions of the matching and reference arms, measured position sense bias or systematic error. The respective standard deviation of the differences between the match and reference arm angular positions (SDPdiff) indicated position sense precision or random error. The main results are as follows: First, systematic error, measured by PE, did not change significantly from early childhood to late adolescence (Median PE at 90° target: −2.85° in early childhood; −2.28° in adolescence; and 1.30° in adults). Second, response variability as measured by SDPdiff significantly decreased with age (Median SDPdiff at 90° target: 9.66° in early childhood; 5.30° in late adolescence; and 3.97° in adults). The data of this large cross-sectional sample of children document that proprioceptive development in typically developing children is characterized as an age-related improvement in precision, not as a development or change in bias. In other words, it is the reliability of the perceptual response that improves between early childhood and adulthood. This study provides normative data against which position sense acuity in pediatric patient populations can be compared. The underlying neurophysiological processes that could explain the observed

  10. Evaluation of vernier acuity near healed retinal laser lesions

    NASA Astrophysics Data System (ADS)

    Schmeisser, Elmar T.

    1997-05-01

    Seven Cynomolgus fasciculata who had graded laser lesions placed in own eye 6 years previously were evaluated for their vernier acuity by electrophysiologic recording techniques. In these experiments, 95 percent contrast vernier acuity targets were presented at high luminance levels to anesthetized primates. Visual evoked potentials were recorded by conventional means form scalp electrodes through hospital grade amplifiers. All animal testing was performed under IACUC approved protocols. The single q-switched pulses form a neodymium-YAG laser had produced lesions of 4 types: no visible change, minimal visible lesions, 'white dot' lesions and 'red dot' lesions in the eye at the time of placement. Single exposures had been made in four locations: 5 degrees superior, inferior and temporal to the fovea, and one foveally. Vernier recording proved somewhat successful in smaller animals with less than contained retinal hemorrhage lesions in the fovea. Initial analyses demonstrated a significant decrease of the pattern response signal/noise in the experimental eye overall, and an apparent relative loss of vernier signal in some lesioned eyes. Animals with the more severe lesions have somewhat degraded small patten responses and no recordable vernier response. Apparent lesser losses produced less effect.

  11. Changes in brain morphology in albinism reflect reduced visual acuity.

    PubMed

    Bridge, Holly; von dem Hagen, Elisabeth A H; Davies, George; Chambers, Claire; Gouws, Andre; Hoffmann, Michael; Morland, Antony B

    2014-07-01

    Albinism, in humans and many animal species, has a major impact on the visual system, leading to reduced acuity, lack of binocular function and nystagmus. In addition to the lack of a foveal pit, there is a disruption to the routing of the nerve fibers crossing at the optic chiasm, resulting in excessive crossing of fibers to the contralateral hemisphere. However, very little is known about the effect of this misrouting on the structure of the post-chiasmatic visual pathway, and the occipital lobes in particular. Whole-brain analyses of cortical thickness in a large cohort of subjects with albinism showed an increase in cortical thickness, relative to control subjects, particularly in posterior V1, corresponding to the foveal representation. Furthermore, mean cortical thickness across entire V1 was significantly greater in these subjects compared to controls and negatively correlated with visual acuity in albinism. Additionally, the group with albinism showed decreased gyrification in the left ventral occipital lobe. While the increase in cortical thickness in V1, also found in congenitally blind subjects, has been interpreted to reflect a lack of pruning, the decreased gyrification in the ventral extrastriate cortex may reflect the reduced input to the foveal regions of the ventral visual stream. PMID:23039995

  12. Crossmodal temporal order and processing acuity in developmentally dyslexic young adults.

    PubMed

    Laasonen, Marja; Service, Elisabet; Virsu, Veijo

    2002-03-01

    We investigated crossmodal temporal performance in processing rapid sequential nonlinguistic events in developmentally dyslexic young adults (ages 20-36 years) and an age- and IQ-matched control group in audiotactile, visuotactile, and audiovisual combinations. Two methods were used for estimating 84% correct temporal acuity thresholds: temporal order judgment (TOJ) and temporal processing acuity (TPA). TPA requires phase difference detection: the judgment of simultaneity/nonsimultaneity of brief stimuli in two parallel, spatially separate triplets. The dyslexic readers' average temporal performance was somewhat poorer in all six comparisons; in audiovisual comparisons the group differences were not statistically significant, however. A principal component analysis indicated that temporal acuity and phonological awareness are related in dyslexic readers. The impairment of temporal input processing seems to be a general correlative feature of dyslexia in children and adults, but the overlap in performance between dyslexic and normal readers suggests that it is not a sufficient reason for developmental reading difficulties. PMID:11896646

  13. Using the Significant Learning Taxonomy and Active Learning to Improve Accounting Education

    ERIC Educational Resources Information Center

    Killian, Larita J.; Brandon, Christopher D.

    2009-01-01

    Like other members of the academy, accounting professors are challenged to improve student learning. We must help students move beyond the "bean counter" role and develop higher-level skills such as analysis, synthesis, and problem-solving. The Significant Learning Taxonomy was used as a template to improve learning in an introductory accounting…

  14. Visual acuity and associated factors. The Central India Eye and Medical Study.

    PubMed

    Nangia, Vinay; Jonas, Jost B; Sinha, Ajit; Gupta, Rajesh; Agarwal, Shubhra

    2011-01-01

    Visual acuity is a major parameter for quality of vision and quality of life. Information on visual acuity and its associated factors in rural societies almost untouched by any industrialization is mostly non-available. It was, therefore, the purpose of our study to determine the distribution of visual acuity and its associated factors in a rural population not marked influenced by modern lifestyle. The population-based Central India Eye and Medical Study included 4711 subjects (aged 30+ years), who underwent a detailed ophthalmologic examination including visual acuity measurement. Visual acuity measurements were available for 4706 subjects with a mean age of 49.5±13.4 years (range: 30-100 years). BCVA decreased significantly (P<0.001) from the moderately hyperopic group (0.08±0.15 logMAR) to the emmetropic group (0.16±0.52 logMAR), the moderately myopic group (0.28±0.33 logMAR), the highly hyperopic group (0.66±0.62 logMAR) and finally the highly myopic group (1.32±0.92 logMAR). In multivariate analysis, BCVA was significantly associated with the systemic parameters of lower age (P<0.001), higher level of education (P<0.001), higher body stature (P<0.001) and higher body mass index (P<0.001), and with the ophthalmic parameters of more hyperopic refractive error (spherical equivalent) (P<0.001), shorter axial length (P<0.001), lower degree of nuclear cataract (P<0.001), and lower intraocular pressure (P = 0.006). The results suggest that in the rural population of Central India, major determinants of visual acuity were socioeconomic background, body stature and body mass index, age, refractive error, cataract and intraocular pressure. PMID:21829503

  15. Brief Report: Visual Acuity in Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Albrecht, Matthew A.; Stuart, Geoffrey W.; Falkmer, Marita; Ordqvist, Anna; Leung, Denise; Foster, Jonathan K.; Falkmer, Torbjorn

    2014-01-01

    Recently, there has been heightened interest in suggestions of enhanced visual acuity in autism spectrum disorders (ASD) which was sparked by evidence that was later accepted to be methodologically flawed. However, a recent study that claimed children with ASD have enhanced visual acuity (Brosnan et al. in "J Autism Dev Disord"…

  16. Reduction in Dynamic Visual Acuity Reveals Gaze Control Changes Following Spaceflight

    NASA Technical Reports Server (NTRS)

    Peters, Brian T.; Brady, Rachel A.; Miller, Chris; Lawrence, Emily L.; Mulavara Ajitkumar P.; Bloomberg, Jacob J.

    2010-01-01

    INTRODUCTION: Exposure to microgravity causes adaptive changes in eye-head coordination that can lead to altered gaze control. This could affect postflight visual acuity during head and body motion. The goal of this study was to characterize changes in dynamic visual acuity after long-duration spaceflight. METHODS: Dynamic Visual Acuity (DVA) data from 14 astro/cosmonauts were collected after long-duration (6 months) spaceflight. The difference in acuity between seated and walking conditions provided a metric of change in the subjects ability to maintain gaze fixation during self-motion. In each condition, a psychophysical threshold detection algorithm was used to display Landolt ring optotypes at a size that was near each subject s acuity threshold. Verbal responses regarding the orientation of the gap were recorded as the optotypes appeared sequentially on a computer display 4 meters away. During the walking trials, subjects walked at 6.4 km/h on a motorized treadmill. RESULTS: A decrement in mean postflight DVA was found, with mean values returning to baseline within 1 week. The population mean showed a consistent improvement in DVA performance, but it was accompanied by high variability. A closer examination of the individual subject s recovery curves revealed that many did not follow a pattern of continuous improvement with each passing day. When adjusted on the basis of previous long-duration flight experience, the population mean shows a "bounce" in the re-adaptation curve. CONCLUSION: Gaze control during self-motion is altered following long-duration spaceflight and changes in postflight DVA performance indicate that vestibular re-adaptation may be more complex than a gradual return to normal.

  17. Visual acuity in the short-tailed opossum (Monodelphis domestica)

    PubMed Central

    Dooley, James C.; Nguyen, Hoang; Seelke, Adele M. H.; Krubitzer, Leah

    2013-01-01

    Monodelphis domestica (short-tailed opossum) is an emerging animal model for studies of neural development due to the extremely immature state of the nervous system at birth and its subsequent rapid growth to adulthood. Yet little is known about its normal sensory discrimination abilities. In the present investigation, visual acuity was determined in this species using the optokinetic test (OPT), which relies on involuntary head tracking of a moving stimulus and can be easily elicited using a rotating visual stimulus of varying spatial frequencies. Using this methodology, we determined that the acuity of Monodelphis is 0.58 cycles per degree (cpd), which is similar to the acuity of rats using the same methodology, and higher than in mice. However, acuity in the short-tailed opossum is lower than in other marsupials. This is in part due to the methodology used to determine acuity, but may also be due to differences in diel patterns, lifestyle and phylogeny. We demonstrate that for the short-tailed opossum, the OPT is a rapid and reliable method of determining a baseline acuity and can be used to study enhanced acuities due to cortical plasticity. PMID:22871523

  18. Retinal Glial Cells Enhance Human Vision Acuity

    NASA Astrophysics Data System (ADS)

    Labin, A. M.; Ribak, E. N.

    2010-04-01

    We construct a light-guiding model of the retina outside the fovea, in which an array of glial (Muller) cells permeates the depth of the retina down to the photoreceptors. Based on measured refractive indices, we propagate light to obtain a significant increase of the intensity at the photoreceptors. For pupils up to 6 mm width, the coupling between neighboring cells is only a few percent. Low cross talk over the whole visible spectrum also explains the insensitivity to chromatic aberrations of the eye. The retina is revealed as an optimal structure designed for improving the sharpness of images.

  19. Automatic coronary lumen segmentation with partial volume modeling improves lesions' hemodynamic significance assessment

    NASA Astrophysics Data System (ADS)

    Freiman, M.; Lamash, Y.; Gilboa, G.; Nickisch, H.; Prevrhal, S.; Schmitt, H.; Vembar, M.; Goshen, L.

    2016-03-01

    The determination of hemodynamic significance of coronary artery lesions from cardiac computed tomography angiography (CCTA) based on blood flow simulations has the potential to improve CCTA's specificity, thus resulting in improved clinical decision making. Accurate coronary lumen segmentation required for flow simulation is challenging due to several factors. Specifically, the partial-volume effect (PVE) in small-diameter lumina may result in overestimation of the lumen diameter that can lead to an erroneous hemodynamic significance assessment. In this work, we present a coronary artery segmentation algorithm tailored specifically for flow simulations by accounting for the PVE. Our algorithm detects lumen regions that may be subject to the PVE by analyzing the intensity values along the coronary centerline and integrates this information into a machine-learning based graph min-cut segmentation framework to obtain accurate coronary lumen segmentations. We demonstrate the improvement in hemodynamic significance assessment achieved by accounting for the PVE in the automatic segmentation of 91 coronary artery lesions from 85 patients. We compare hemodynamic significance assessments by means of fractional flow reserve (FFR) resulting from simulations on 3D models generated by our segmentation algorithm with and without accounting for the PVE. By accounting for the PVE we improved the area under the ROC curve for detecting hemodynamically significant CAD by 29% (N=91, 0.85 vs. 0.66, p<0.05, Delong's test) with invasive FFR threshold of 0.8 as the reference standard. Our algorithm has the potential to facilitate non-invasive hemodynamic significance assessment of coronary lesions.

  20. Rehearsal significantly improves immediate and delayed recall on the Rey Auditory Verbal Learning Test.

    PubMed

    Hessen, Erik

    2011-10-01

    A repeated observation during memory assessment with the Rey Auditory Verbal Learning Test (RAVLT) is that patients who spontaneously employ a memory rehearsal strategy by repeating the word list more than once achieve better scores than patients who only repeat the word list once. This observation led to concern about the ability of the standard test procedure of RAVLT and similar tests in eliciting the best possible recall scores. The purpose of the present study was to test the hypothesis that a rehearsal recall strategy of repeating the word list more than once would result in improved scores of recall on the RAVLT. We report on differences in outcome after standard administration and after experimental administration on Immediate and Delayed Recall measures from the RAVLT of 50 patients. The experimental administration resulted in significantly improved scores for all the variables employed. Additionally, it was found that patients who failed effort screening showed significantly poorer improvement on Delayed Recall compared with those who passed the effort screening. The general clear improvement both in raw scores and T-scores demonstrates that recall performance can be significantly influenced by the strategy of the patient or by small variations in instructions by the examiner. PMID:22074064

  1. Group mindfulness-based therapy significantly improves sexual desire in women.

    PubMed

    Brotto, Lori A; Basson, Rosemary

    2014-06-01

    At least a third of women across reproductive ages experience low sexual desire and impaired arousal. There is increasing evidence that mindfulness, defined as non-judgmental present moment awareness, may improve women's sexual functioning. The goal of this study was to test the effectiveness of mindfulness-based therapy, either immediately or after a 3-month waiting period, in women seeking treatment for low sexual desire and arousal. Women participated in four 90-min group sessions that included mindfulness meditation, cognitive therapy, and education. A total of 117 women were assigned to either the immediate treatment (n = 68, mean age 40.8 yrs) or delayed treatment (n = 49, mean age 42.2 yrs) group, in which women had two pre-treatment baseline assessments followed by treatment. A total of 95 women completed assessments through to the 6-month follow-up period. Compared to the delayed treatment control group, treatment significantly improved sexual desire, sexual arousal, lubrication, sexual satisfaction, and overall sexual functioning. Sex-related distress significantly decreased in both conditions, regardless of treatment, as did orgasmic difficulties and depressive symptoms. Increases in mindfulness and a reduction in depressive symptoms predicted improvements in sexual desire. Mindfulness-based group therapy significantly improved sexual desire and other indices of sexual response, and should be considered in the treatment of women's sexual dysfunction. PMID:24814472

  2. Evaluation of vestibular and dynamic visual acuity in adults with congenital deafness.

    PubMed

    Nakajima, Yukinori; Kaga, Kimitaka; Takekoshi, Hideki; Sakuraba, Keisyoku

    2012-10-01

    This study compared vestibular and dynamic visual acuity in 19 adult athletes with deafness participating in Deaflympics to those of 25 young adults with normal hearing. Balance capability was evaluated using a one-leg standing test with eyes open and stabilometry. Caloric tests and vestibular evoked myogenic potential tests were conducted to test vestibular function. Visual function was evaluated using a dynamic visual acuity test. No significant difference was found between results of the one-leg standing test with eyes open and stabilometry with eyes open. Athletes with deafness performed better than normal hearing young adults with eyes closed. The caloric test indicated hypofunction of the lateral semicircular canal function in 5 of the 19 athletes with deafness. Balance-function tests showed normal results for both groups. The results for athletes with deafness on visual acuity were better than those of controls. Young Deaflympics athletes with deafness can adjust their balance function as well as or better than normal hearing young adults using dynamic visual acuity. PMID:23265013

  3. Visual Vestibular Interaction in the Dynamic Visual Acuity Test during Voluntary Head Rotation

    NASA Technical Reports Server (NTRS)

    Lee, Moo Hoon; Durnford, Simon; Crowley, John; Rupert, Angus

    1996-01-01

    Although intact vestibular function is essential in maintaining spatial orientation, no good screening tests of vestibular function are available to the aviation community. High frequency voluntary head rotation was selected as a vestibular stimulus to isolate the vestibulo-ocular reflex (VOR) from visual influence. A dynamic visual acuity test that incorporates voluntary head rotation was evaluated as a potential vestibular function screening tool. Twenty-seven normal subjects performed voluntary sinusoidal head rotation at frequencies from 0.7-4.0 Hz under three different visual conditions: visually-enhanced VOR, normal VOR, and visually suppressed VOR. Standardized Baily-Lovie chart letters were presented on a computer monitor in front of the subject, who then was asked to read the letters while rotating his head horizontally. The electro-oculogram and dynamic visual acuity score were recorded and analyzed. There were no significant differences in gain or phase shift among three visual conditions in the frequency range of 2.8 to 4.0 Hz. The dynamic visual acuity score shifted less than 0.3 logMAR at frequencies under 2.0 Hz. The dynamic visual acuity test at frequencies a round 2.0 Hz can be recommended for evaluating vestibular function.

  4. Visual acuity changes in rhesus following low-level Q-switched exposures

    NASA Astrophysics Data System (ADS)

    Robbins, David O.; Zwick, Harry; Bearden, Bradley D.; Evans, Brenda S.; Stuck, Bruce E.

    1997-05-01

    Previously we have shown that visual deficits can be produced by long duration pulses at or slightly below traditional threshold levels for retinal injury. Initially the deficits produced were only transient shifts in baseline acuity that lasted less than 30 min, but successive exposures over a period of days at these same power levels were shown to be cumulative and their impact on visual acuity lengthened and became permanent. The present investigation extended these exposures to Q-switched, 532 nm Nd/YAG pulses presented to awake, task-oriented nonhuman primates performing Landolt ring discriminations. At and above the ED50, single pulses of minimal spot diameter produced only minor, transient shifts in visual acuity while repeated exposures produced significant shifts in acuity that became permanent over time. At lower energies, minimal spot, single-pulsed exposures again produced little observable consequence until either retinal spot sizes or number of pulses were increased. At these lower energy levels, however, no permanent functional loss was observed. Hence, the functional impact of single Q-switched pulses was more difficult to assess than longer time domain exposures. Multiple, low level Q-switched pulses, and/or larger spot sizes produced visual deficits similar to those observed for msec time domain exposures, suggesting both temporal and spatial summation at energy levels where no permanent effects have been noted.

  5. Determination of significance in Ecological Impact Assessment: Past change, current practice and future improvements

    SciTech Connect

    Briggs, Sam; Hudson, Malcolm D.

    2013-01-15

    Ecological Impact Assessment (EcIA) is an important tool for conservation and achieving sustainable development. 'Significant' impacts are those which disturb or alter the environment to a measurable degree. Significance is a crucial part of EcIA, our understanding of the concept in practice is vital if it is to be effective as a tool. This study employed three methods to assess how the determination of significance has changed through time, what current practice is, and what would lead to future improvements. Three data streams were collected: interviews with expert stakeholders, a review of 30 Environmental Statements and a broad-scale survey of the United Kingdom Institute of Ecology and Environmental Management (IEEM) members. The approach taken in the determination of significance has become more standardised and subjectivity has become constrained through a transparent framework. This has largely been driven by a set of guidelines produced by IEEM in 2006. The significance of impacts is now more clearly justified and the accuracy with which it is determined has improved. However, there are limitations to accuracy and effectiveness of the determination of significance. These are the quality of baseline survey data, our scientific understanding of ecological processes and the lack of monitoring and feedback of results. These in turn are restricted by the limited resources available in consultancies. The most notable recommendations for future practice are the implementation of monitoring and the publication of feedback, the creation of a central database for baseline survey data and the streamlining of guidance. - Highlights: Black-Right-Pointing-Pointer The assessment of significance has changed markedly through time. Black-Right-Pointing-Pointer The IEEM guidelines have driven a standardisation of practice. Black-Right-Pointing-Pointer Currently limited by quality of baseline data and scientific understanding. Black-Right-Pointing-Pointer Monitoring and

  6. Is acuity enough? Other considerations in clinical investigations of visual prostheses.

    PubMed

    Lepri, Bernard P

    2009-06-01

    Visual impairing eye diseases are the major frontier facing ophthalmic research today in light of our rapidly aging population. The visual skills necessary for improving the quality of daily function and life are inextricably linked to these impairing diseases. Both research and reimbursement programs are emphasizing outcome-based results. Is improvement in visual acuity alone enough to improve the function and quality of life of visually impaired persons? This perspective summarizes the types of effectiveness endpoints for clinical investigations of visual prostheses that go beyond visual acuity. The clinical investigation of visual prostheses should include visual function, functional vision and quality of life measures. Specifically, they encompass contrast sensitivity, orientation and mobility, activities of daily living and quality of life assessments. The perspective focuses on the design of clinical trials for visual prostheses and the methods of determining effectiveness above and beyond visual acuity that will yield outcomes that are measured by improved function in the visual world and quality of life. The visually impaired population is the primary consideration in this presentation with particular emphases on retinitis pigmentosa and age-related macular degeneration. Clinical trials for visual prostheses cannot be isolated from the need for medical rehabilitation in order to obtain measurements of effectiveness that produce outcomes/evidence-based success. This approach will facilitate improvement in daily function and quality of life of patients with diseases that cause chronic vision impairment. PMID:19458402

  7. Assessment of imaging with extended depth-of-field by means of the light sword lens in terms of visual acuity scale

    PubMed Central

    Kakarenko, Karol; Ducin, Izabela; Grabowiecki, Krzysztof; Jaroszewicz, Zbigniew; Kolodziejczyk, Andrzej; Mira-Agudelo, Alejandro; Petelczyc, Krzysztof; Składowska, Aleksandra; Sypek, Maciej

    2015-01-01

    We present outcomes of an imaging experiment using the refractive light sword lens (LSL) as a contact lens in an optical system that serves as a simplified model of the presbyopic eye. The results show that the LSL produces significant improvements in visual acuity of the simplified presbyopic eye model over a wide range of defocus. Therefore, this element can be an interesting alternative for the multifocal contact and intraocular lenses currently used in ophthalmology. The second part of the article discusses possible modifications of the LSL profile in order to render it more suitable for fabrication and ophthalmological applications. PMID:26137376

  8. Assessment of imaging with extended depth-of-field by means of the light sword lens in terms of visual acuity scale.

    PubMed

    Kakarenko, Karol; Ducin, Izabela; Grabowiecki, Krzysztof; Jaroszewicz, Zbigniew; Kolodziejczyk, Andrzej; Mira-Agudelo, Alejandro; Petelczyc, Krzysztof; Składowska, Aleksandra; Sypek, Maciej

    2015-05-01

    We present outcomes of an imaging experiment using the refractive light sword lens (LSL) as a contact lens in an optical system that serves as a simplified model of the presbyopic eye. The results show that the LSL produces significant improvements in visual acuity of the simplified presbyopic eye model over a wide range of defocus. Therefore, this element can be an interesting alternative for the multifocal contact and intraocular lenses currently used in ophthalmology. The second part of the article discusses possible modifications of the LSL profile in order to render it more suitable for fabrication and ophthalmological applications. PMID:26137376

  9. Communication: Proper treatment of classically forbidden electronic transitions significantly improves detailed balance in surface hopping.

    PubMed

    Sifain, Andrew E; Wang, Linjun; Prezhdo, Oleg V

    2016-06-01

    Surface hopping is the most popular method for nonadiabatic molecular dynamics. Many have reported that it does not rigorously attain detailed balance at thermal equilibrium, but does so approximately. We show that convergence to the Boltzmann populations is significantly improved when the nuclear velocity is reversed after a classically forbidden hop. The proposed prescription significantly reduces the total number of classically forbidden hops encountered along a trajectory, suggesting that some randomization in nuclear velocity is needed when classically forbidden hops constitute a large fraction of attempted hops. Our results are verified computationally using two- and three-level quantum subsystems, coupled to a classical bath undergoing Langevin dynamics. PMID:27276938

  10. Significantly Improved Mechanical Properties of Bi- Sn Solder Alloys by Ag- Doping

    NASA Astrophysics Data System (ADS)

    McCormack, M.; Chen, H. S.; Kammlott, G. W.; Jin, S.

    1997-08-01

    The addition of small amounts of Ag (less than ~;0.5 wt. %) is found to significantly improve the ductility of the binary Bi-Sn eutectic solder. The ductility improvement, more than a threefold increase in tensile elongation, is observed even at a relatively high strain rate (0.01 s-1). As the Bi-Sn binary eutectic alloy tends to fail catastrophically by brittle fracture at high strain rates, the reduced strain-rate sensitivity in the Ag-containing alloy is beneficial for improving solder reliability on sudden impacting as might be encountered during device assembly, shipping, or thermal shock/cycling. The observed increase in alloy ductility by Ag additions is attributed to a substantial refinement of the solidification microstructure.

  11. Baseline Characteristics of the Infant Aphakia Treatment Study Population: Predicting Recognition Acuity at 4.5 Years of Age

    PubMed Central

    Hartmann, E. Eugenie; Lynn, Michael J.; Lambert, Scott R.

    2015-01-01

    Purpose. To identify patient baseline characteristics that predict recognition acuity at 4.5 years of age in the Infant Aphakia Treatment Study, a study of patients with monocular infantile cataracts. Methods. We analyzed baseline characteristics of the 114 infants enrolled in the Infant Aphakia Treatment Study to determine which were most predictive of visual outcome at 4.5 years of age. All infants underwent cataract surgery between 1 and 7 months of age. Monocular acuity was assessed at 4.5 years of age by a traveling examiner using the Amblyopia Treatment Study HOTV protocol. Results. Age at cataract surgery was weakly associated with visual acuity (Spearman rank correlation coefficient = 0.19, P = 0.041) with median visual acuity better among the younger patients (28–48 days: 0.50 logMAR, 49–210 days: 1.10 logMAR, P = 0.046). Patients from families with private insurance had significantly better median visual acuity (0.60 vs. 1.40 logMAR, P = 0.0004). No other baseline characteristic revealed a significant bivariate relationship with visual acuity. A multiple linear regression relating visual acuity to all baseline characteristics demonstrated that only the availability of private insurance was statistically significant, accounting for 12% of the variance. Conclusions. This analysis concurs with previous studies that early surgery is important for good visual outcomes in patients with unilateral infantile cataracts. The fact that only one baseline variable (private insurance) contributed to the multivariate analysis, accounting for 12% of the variance, suggests that predicting visual outcome for these patients is complicated at best, and cannot be estimated from baseline characteristics alone. (ClinicalTrials.gov number, NCT00212134.) PMID:25503455

  12. Comparison of improved operating parameters of five different wavelength LEDs for significantly brighter illumination

    NASA Astrophysics Data System (ADS)

    Mueller, Eduard K.; Lee, Susanne M.; Van de Workeen, Brian C.; Mueller, Otward M.

    2001-05-01

    Although light-emitting diodes exhibit much higher efficiencies and greatly reduced power consumption compared to incandescent light sources, the use of LEDs in lighting applications is limited by their smaller size and subsequently lower light output. However, it has been found that these parameters can be increased significantly by cooling the diodes to cryogenic temperatures. This may make their use feasible for several applications requiring more efficient and brighter illumination for much less cost. In this paper, we compare the temperature-dependent behavior of five commercially available LEDs of different wavelengths down to liquid nitrogen temperatures. It was found that three AlInGaP diodes (red, yellow, and green) demonstrated significant operating improvements. The performance of InGaN-based blue LEDs declined at low temperatures, and because most white LEDs are simply blue LEDs coated with YAG, these exhibited similar behavior. However, the three AlInGaP LEDs demonstrated at least an order of magnitude improvement in illuminance, absolute intensity, and maximum operating current. The green LEDs showed the largest improvement factors, while the yellow LEDs produced the brightest illumination at low temperatures. The emissions of all five LEDs shifted to shorter wavelengths at low temperatures. This is significant in terms of lighting applications since the low-temperature AlInGaP diodes emitted more visible spectra.

  13. 49 CFR 242.117 - Vision and hearing acuity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... required in 29 CFR 1910.95(h) (OSHA); (2) As required in § 227.111 of this chapter; or (3) Conducted using... 49 Transportation 4 2013-10-01 2013-10-01 false Vision and hearing acuity. 242.117 Section 242.117... Requirements § 242.117 Vision and hearing acuity. (a) Each railroad shall adopt and comply with a program...

  14. 49 CFR 242.117 - Vision and hearing acuity.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... required in 29 CFR 1910.95(h) (OSHA); (2) As required in § 227.111 of this chapter; or (3) Conducted using... 49 Transportation 4 2014-10-01 2014-10-01 false Vision and hearing acuity. 242.117 Section 242.117... Requirements § 242.117 Vision and hearing acuity. (a) Each railroad shall adopt and comply with a program...

  15. 49 CFR 242.117 - Vision and hearing acuity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... required in 29 CFR 1910.95(h) (OSHA); (2) As required in § 227.111 of this chapter; or (3) Conducted using... 49 Transportation 4 2012-10-01 2012-10-01 false Vision and hearing acuity. 242.117 Section 242.117... Requirements § 242.117 Vision and hearing acuity. (a) Each railroad shall adopt and comply with a program...

  16. Etiology of reduced visual acuity in congenital nystagmus.

    PubMed

    Spierer, A

    1991-10-01

    A study was undertaken to identify the etiologic factor of reduced visual acuity in congenital nystagmus. Fourteen children with congenital nystagmus and reduced visual acuity were examined, using a modified "E" game test. Their success rate in identifying vertical lines was compared with their success rate in identifying horizontal lines. The children identified both vertical and horizontal lines with a similar rate of success. These results may indicate that poor vision in congenital nystagmus patients is partly the result of amblyopia. PMID:1755616

  17. Lingual tactile acuity and food texture preferences among children and their mothers

    PubMed Central

    Lukasewycz, Laura D.; Mennella, Julie A.

    2012-01-01

    Despite anecdotal reports of children being more sensitive to texture than adults, and of texture being one of the main drivers of food aversions, there is a paucity of scientific knowledge on the influence of texture perception on food choice in children. The primary goals of this study were to assess the use of a modified letter-identification task to study lingual tactile acuity, one aspect of oral sensitivity, in children and to examine age-related differences in sensitivity. The secondary goal was to explore whether lingual tactile acuity and age relate to various measures of food choice and preference. To this end, children 7–10 years old (31 girls, 21 boys) and their mothers were tested using identical procedures. To assess lingual tactile acuity, children and mothers were asked to use the tips of their tongues to identify raised alphabetical letters of varying size (2.5–8.0 mm) on Teflon strips. To relate lingual tactile acuity to food texture preferences, a forced-choice questionnaire assessed preferences for foods similar in flavor but different in texture (e.g., smooth versus crunchy peanut butter). Children were able to complete the lingual acuity task as well as their mothers and took less time to assess each letter stimulus (p < 0.001); however, there were no age-related differences in lingual acuity (p = 0.14). Age, but not lingual acuity, related to food texture preferences: mothers preferred harder foods (p < 0.001) and those containing more particles (p < 0.04) than did children, although children‘s preferences became more adult-like with increasing age. The availability of a rapid, child-friendly method for assessing oral sensitivity opens up new possibilities of examining differences in oral tactile perceptions across the life span. That food preferences changed with age and were not related to oral sensitivity underscores the fact that factors such as experience, culture and family food practices have a significant impact on children

  18. PXD101 significantly improves nuclear reprogramming and the in vitro developmental competence of porcine SCNT embryos

    SciTech Connect

    Jin, Jun-Xue; Kang, Jin-Dan; Li, Suo; Jin, Long; Zhu, Hai-Ying; Guo, Qing; Gao, Qing-Shan; Yan, Chang-Guo; Yin, Xi-Jun

    2015-01-02

    Highlights: • First explored that the effects of PXD101 on the development of SCNT embryos in vitro. • 0.5 μM PXD101 treated for 24 h improved the development of porcine SCNT embryos. • Level of AcH3K9 was significantly higher than control group at early stages. - Abstract: In this study, we investigated the effects of the histone deacetylase inhibitor PXD101 (belinostat) on the preimplantation development of porcine somatic cell nuclear transfer (SCNT) embryos and their expression of the epigenetic markers histone H3 acetylated at lysine 9 (AcH3K9). We compared the in vitro developmental competence of SCNT embryos treated with various concentrations of PXD101 for 24 h. Treatment with 0.5 μM PXD101 significantly increased the proportion of SCNT embryos that reached the blastocyst stage, in comparison to the control group (23.3% vs. 11.5%, P < 0.05). We tested the in vitro developmental competence of SCNT embryos treated with 0.5 μM PXD101 for various amounts of times following activation. Treatment for 24 h significantly improved the development of porcine SCNT embryos, with a significantly higher proportion of embryos reaching the blastocyst stage in comparison to the control group (25.7% vs. 10.6%, P < 0.05). PXD101-treated SCNT embryos were transferred into two surrogate sows, one of whom became pregnant and four fetuses developed. PXD101 treatment significantly increased the fluorescence intensity of immunostaining for AcH3K9 in embryos at the pseudo-pronuclear and 2-cell stages. At these stages, the fluorescence intensities of immunostaining for AcH3K9 were significantly higher in PXD101-treated embryos than in control untreated embryos. In conclusion, this study demonstrates that PXD101 can significantly improve the in vitro and in vivo developmental competence of porcine SCNT embryos and can enhance their nuclear reprogramming.

  19. Active Hemovigilance Significantly Improves Reporting of Acute Non-infectious Adverse Reactions to Blood Transfusion.

    PubMed

    Agnihotri, Naveen; Agnihotri, Ajju

    2016-09-01

    One of the key purposes of a hemovigilance program is to improve reporting of transfusion related adverse events and subsequent data-driven improvement in blood transfusion (BT) practices. We conducted a study over 3 years to assess the impact of healthcare worker training and an active feedback programme on reporting of adverse reactions to BTs. All hospitalized patients who required a BT were included in the study. Healthcare workers involved in BT to patients were sensitized and trained in adverse reaction reporting by conducting training sessions and meetings. All the transfused patients were 'actively' monitored for any acute adverse reaction by using a uniquely coded blood issue form. A total of 18,914 blood components transfused to 5785 different patients resulted in 61 adverse reaction episodes. This incidence of 0.32 % in our study was found to be significantly higher (p < 0.005) than that reported from the same region in the past. Red blood cell units were the most frequently transfused component and thus most commonly involved in an adverse reaction (42.6 %), however apheresis platelets had the highest chance of reaction per unit transfused (0.66 %). There was no mortality associated with the BT during the study period. An active surveillance program significantly improves reporting and management of adverse reactions to BTs. PMID:27429527

  20. Storage of human pancreatic digest in University of Wisconsin solution significantly improves subsequent islet purification.

    PubMed

    Robertson, G S; Chadwick, D; Contractor, H; Rose, S; Chamberlain, R; Clayton, H; Bell, P R; James, R F; London, N J

    1992-09-01

    Density-gradient purification of human pancreatic islets from the collagenase-digested pancreas relies on the exocrine tissue being denser than the islets. Cold storage of the pancreas before and after digestion causes cell swelling, which can decrease the density of pancreatic exocrine tissue and adversely affect subsequent purification. Using 14 human pancreata (seven perfused in situ with hyperosmolar citrate (HOC) and seven with University of Wisconsin solution (UW)), it is shown that storage of the pancreatic digest in UW significantly increases the density of pancreatic exocrine tissue compared with storage in minimal essential medium (MEM) (P = 0.009). This results in an improvement in islet purity (P = 0.036) for HOC- but not UW-perfused pancreata. Storage in UW for 1 h not only prevented the deterioration that occurred in MEM, but resulted in an improvement in islet purity for five of the seven HOC-perfused pancreata. Most pancreata in the UK are perfused with HOC, but storage of the digest in UW results in significantly better islet purity and, when islets cannot be purified immediately, a period of storage will often improve separation and allow islets to be purified. PMID:1422750

  1. Insects groom their antennae to enhance olfactory acuity

    PubMed Central

    Böröczky, Katalin; Wada-Katsumata, Ayako; Batchelor, Dale; Zhukovskaya, Marianna; Schal, Coby

    2013-01-01

    Grooming, a common behavior in animals, serves the important function of removing foreign materials from body surfaces. When antennal grooming was prevented in the American cockroach, Periplaneta americana, field emission gun scanning electron microscopy images revealed that an unstructured substance accumulated on nongroomed antennae, covering sensillar pores, but not on groomed antennae of the same individuals. Gas chromatography analysis of antennal extracts showed that over a 24-h period nongroomed antennae accumulated three to four times more cuticular hydrocarbons than groomed antennae. Moreover, nongroomed antennae accumulated significantly more environmental contaminants from surfaces (stearic acid) and from air (geranyl acetate) than groomed antennae. We hypothesized that the accumulation of excess native cuticular hydrocarbons on the antennae would impair olfactory reception. Electroantennogram experiments and single-sensillum recordings supported this hypothesis: antennae that were prevented from being groomed were significantly less responsive than groomed antennae to the sex pheromone component periplanone-B, as well as to the general odorants geranyl acetate and hexanol. We therefore conclude that antennal grooming removes excess native cuticular lipids and foreign chemicals that physically and/or chemically interfere with olfaction, and thus maintains the olfactory acuity of the antennae. Similar experimental manipulations of the German cockroach (Blattella germanica), carpenter ant (Camponotus pennsylvanicus), and the housefly (Musca domestica), which use different modes of antennal grooming, support the hypothesis that antennal grooming serves a similar function in a wide range of insect taxa. PMID:23382193

  2. Insects groom their antennae to enhance olfactory acuity.

    PubMed

    Böröczky, Katalin; Wada-Katsumata, Ayako; Batchelor, Dale; Zhukovskaya, Marianna; Schal, Coby

    2013-02-26

    Grooming, a common behavior in animals, serves the important function of removing foreign materials from body surfaces. When antennal grooming was prevented in the American cockroach, Periplaneta americana, field emission gun scanning electron microscopy images revealed that an unstructured substance accumulated on nongroomed antennae, covering sensillar pores, but not on groomed antennae of the same individuals. Gas chromatography analysis of antennal extracts showed that over a 24-h period nongroomed antennae accumulated three to four times more cuticular hydrocarbons than groomed antennae. Moreover, nongroomed antennae accumulated significantly more environmental contaminants from surfaces (stearic acid) and from air (geranyl acetate) than groomed antennae. We hypothesized that the accumulation of excess native cuticular hydrocarbons on the antennae would impair olfactory reception. Electroantennogram experiments and single-sensillum recordings supported this hypothesis: antennae that were prevented from being groomed were significantly less responsive than groomed antennae to the sex pheromone component periplanone-B, as well as to the general odorants geranyl acetate and hexanol. We therefore conclude that antennal grooming removes excess native cuticular lipids and foreign chemicals that physically and/or chemically interfere with olfaction, and thus maintains the olfactory acuity of the antennae. Similar experimental manipulations of the German cockroach (Blattella germanica), carpenter ant (Camponotus pennsylvanicus), and the housefly (Musca domestica), which use different modes of antennal grooming, support the hypothesis that antennal grooming serves a similar function in a wide range of insect taxa. PMID:23382193

  3. Surgically-Induced Weight Loss Significantly Improves Nonalcoholic Fatty Liver Disease and the Metabolic Syndrome

    PubMed Central

    Mattar, Samer G.; Velcu, Laura M.; Rabinovitz, Mordechai; Demetris, A J.; Krasinskas, A M.; Barinas-Mitchell, Emma; Eid, George M.; Ramanathan, Ramesh; Taylor, Debra S.; Schauer, Philip R.

    2005-01-01

    Objective: To evaluate the effects of surgical weight loss on fatty liver disease in severely obese patients. Summary Background Data: Nonalcoholic fatty liver disease (NAFLD), a spectrum that extends to liver fibrosis and cirrhosis, is rising at an alarming rate. This increase is occurring in conjunction with the rise of severe obesity and is probably mediated in part by metabolic syndrome (MS). Surgical weight loss operations, probably by reversing MS, have been shown to result in improvement in liver histology. Methods: Patients who underwent laparoscopic surgical weight loss operations from March 1999 through August 2004, and who agreed to have an intraoperative liver biopsy followed by at least one postoperative liver biopsy, were included. Results: There were 70 patients who were eligible. All patients underwent laparoscopic operations, the majority being laparoscopic Roux-en-Y gastric bypass. The mean excess body weight loss at time of second biopsy was 59% ± 22% and the time interval between biopsies was 15 ± 9 months. There was a reduction in prevalence of metabolic syndrome, from 70% to 14% (P < 0.001), and a marked improvement in liver steatosis (from 88% to 8%), inflammation (from 23% to 2%), and fibrosis (from 31% to 13%; all P < 0.001). Inflammation and fibrosis resolved in 37% and 20% of patients, respectively, corresponding to improvement of 82% (P < 0.001) in grade and 39% (P < 0.001) in stage of liver disease. Conclusion: Surgical weight loss results in significant improvement of liver morphology in severely obese patients. These beneficial changes may be associated with a significant reduction in the prevalence of the metabolic syndrome. PMID:16192822

  4. Intestinal-borne dermatoses significantly improved by oral application of Escherichia coli Nissle 1917

    PubMed Central

    Manzhalii, Elina; Hornuss, Daniel; Stremmel, Wolfgang

    2016-01-01

    AIM: To evaluate the effect of oral Escherichia coli (E. coli) Nissle application on the outcome of intestinal-borne dermatoses. METHODS: In a randomized, controlled, non-blinded prospective clinical trial 82 patients with intestinal-borne facial dermatoses characterized by an erythematous papular-pustular rash were screened. At the initiation visit 37 patients entered the experimental arm and 20 patients constituted the control arm. All 57 patients were treated with a vegetarian diet and conventional topical therapy of the dermatoses with ointments containing tetracycline, steroids and retinoids. In the experimental arm patients received a one month therapy with oral E. coli Nissle at a maintenance dose of 2 capsules daily. The experimental group was compared to a non-treatment group only receiving the diet and topical therapy. The primary outcome parameter was improvement of the dermatoses, secondary parameters included life quality and adverse events. In addition the immunological reaction profile (IgA, interleucin-8 and interferon-α) was determined. Furthermore the changes of stool consistency and the microbiota composition over the time of intervention were recorded. RESULTS: Eighty-nine percent of the patients with acne, papular-pustular rosacea and seborrhoic dermatitis responded to E. coli Nissle therapy with significant amelioration or complete recovery in contrast to 56% in the control arm (P < 0.01). Accordingly, in the E. coli Nissle treated patients life quality improved significantly (P < 0.01), and adverse events were not recorded. The clinical improvement was associated with a significant increase of IgA levels to normal values in serum as well as suppression of the proinflammatory cytokine IL-8 (P < 0.01 for both parameters). In the E. coli Nissle treated group a shift towards a protective microbiota with predominance of bifidobacteria and lactobacteria (> 107 CFU/g stool) was observed in 79% and 63% of the patients, respectively (P < 0

  5. [Orally administered polaprezinc significantly improves taste disorders in ovarian cancer patient undergoing chemotherapy].

    PubMed

    Nishijima, Shota; Yanase, Toru; Hata, Yuki; Tamura, Ryo; Tsuneki, Ikunosuke; Tamura, Masaki; Kurabayashi, Takumi

    2011-04-01

    The subject was a 75-year-old female who was receiving paclitaxel and carboplatin(TC)chemotherapy every other week after surgery for ovarian cancer. She greatly complained of taste disorders after four cycles(of every other week administration) of TC chemotherapy. To understand how the taste disorder was caused by chemotherapy objectively, taste examinations were conducted for the patient in our department. These examinations were conducted after receiving the informed consent from the patient. The authors conducted taste examinations for the patient using serum zinc measurement, tongue cell culture, electrogustometry, and filter paper disc tests(before and after starting chemotherapy), and found that her serum zinc level fell significantly after four cycles of chemotherapy. Orally disintegrating tablets of polaprezinc were then administered to the patient, after which the subjective symptom of taste disorder improved. Her serum zinc level increased, and the electrogustometric threshold rapidly fell(an improvement). The filter paper disc test showed some improvement, particularly in the glossopharyngeal nerve and the greater petrosal nerve field. PMID:21499007

  6. Significant Improvements in the Practice Patterns of Adult Related Donor Care in US Transplantation Centers.

    PubMed

    Anthias, Chloe; Shaw, Bronwen E; Kiefer, Deidre M; Liesveld, Jane L; Yared, Jean; Kamble, Rammurti T; D'Souza, Anita; Hematti, Peiman; Seftel, Matthew D; Norkin, Maxim; DeFilipp, Zachariah; Kasow, Kimberly A; Abidi, Muneer H; Savani, Bipin N; Shah, Nirali N; Anderlini, Paolo; Diaz, Miguel A; Malone, Adriana K; Halter, Joerg P; Lazarus, Hillard M; Logan, Brent R; Switzer, Galen E; Pulsipher, Michael A; Confer, Dennis L; O'Donnell, Paul V

    2016-03-01

    Recent investigations have found a higher incidence of adverse events associated with hematopoietic cell donation in related donors (RDs) who have morbidities that if present in an unrelated donor (UD) would preclude donation. In the UD setting, regulatory standards ensure independent assessment of donors, one of several crucial measures to safeguard donor health and safety. A survey conducted by the Center for International Blood and Marrow Transplant Research (CIBMTR) Donor Health and Safety Working Committee in 2007 reported a potential conflict of interest in >70% of US centers, where physicians had simultaneous responsibility for RDs and their recipients. Consequently, several international organizations have endeavored to improve practice through regulations and consensus recommendations. We hypothesized that the changes in the 2012 Foundation for the Accreditation of Cellular Therapy and the Joint Accreditation Committee-International Society for Cellular Therapy and European Society for Blood and Marrow Transplantation standards resulting from the CIBMTR study would have significantly impacted practice. Accordingly, we conducted a follow-up survey of US transplantation centers to assess practice changes since 2007, and to investigate additional areas where RD care was predicted to differ from UD care. A total of 73 centers (53%), performing 79% of RD transplantations in the United States, responded. Significant improvements were observed since the earlier survey; 62% centers now ensure separation of RD and recipient care (P < .0001). This study identifies several areas where RD management does not meet international donor care standards, however. Particular concerns include counseling and assessment of donors before HLA typing, with 61% centers first disclosing donor HLA results to an individual other than the donor, the use of unlicensed mobilization agents, and the absence of long-term donor follow-up. Recommendations for improvement are made. PMID

  7. Carfilzomib significantly improves the progression-free survival of high-risk patients in multiple myeloma

    PubMed Central

    Fonseca, Rafael; Siegel, David; Dimopoulos, Meletios A.; Špička, Ivan; Masszi, Tamás; Hájek, Roman; Rosiñol, Laura; Goranova-Marinova, Vesselina; Mihaylov, Georgi; Maisnar, Vladimír; Mateos, Maria-Victoria; Wang, Michael; Niesvizky, Ruben; Oriol, Albert; Jakubowiak, Andrzej; Minarik, Jiri; Palumbo, Antonio; Bensinger, William; Kukreti, Vishal; Ben-Yehuda, Dina; Stewart, A. Keith; Obreja, Mihaela; Moreau, Philippe

    2016-01-01

    The presence of certain high-risk cytogenetic abnormalities, such as translocations (4;14) and (14;16) and deletion (17p), are known to have a negative impact on survival in multiple myeloma (MM). The phase 3 study ASPIRE (N = 792) demonstrated that progression-free survival (PFS) was significantly improved with carfilzomib, lenalidomide, and dexamethasone (KRd), compared with lenalidomide and dexamethasone (Rd) in relapsed MM. This preplanned subgroup analysis of ASPIRE was conducted to evaluate KRd vs Rd by baseline cytogenetics according to fluorescence in situ hybridization. Of 417 patients with known cytogenetic risk status, 100 patients (24%) were categorized with high-risk cytogenetics (KRd, n = 48; Rd, n = 52) and 317 (76%) were categorized with standard-risk cytogenetics (KRd, n = 147; Rd, n = 170). For patients with high-risk cytogenetics, treatment with KRd resulted in a median PFS of 23.1 months, a 9-month improvement relative to treatment with Rd. For patients with standard-risk cytogenetics, treatment with KRd led to a 10-month improvement in median PFS vs Rd. The overall response rates for KRd vs Rd were 79.2% vs 59.6% (high-risk cytogenetics) and 91.2% vs 73.5% (standard-risk cytogenetics); approximately fivefold as many patients with high- or standard-risk cytogenetics achieved a complete response or better with KRd vs Rd (29.2% vs 5.8% and 38.1% vs 6.5%, respectively). KRd improved but did not abrogate the poor prognosis associated with high-risk cytogenetics. This regimen had a favorable benefit-risk profile in patients with relapsed MM, irrespective of cytogenetic risk status, and should be considered a standard of care in these patients. This trial was registered at www.clinicaltrials.gov as #NCT01080391. PMID:27439911

  8. Intensity-Modulated Radiation Therapy Significantly Improves Acute Gastrointestinal Toxicity in Pancreatic and Ampullary Cancers

    SciTech Connect

    Yovino, Susannah; Poppe, Matthew; Jabbour, Salma; David, Vera; Garofalo, Michael; Pandya, Naimesh; Alexander, Richard; Hanna, Nader; Regine, William F.

    2011-01-01

    Purpose: Among patients with upper abdominal malignancies, intensity-modulated radiation therapy (IMRT) can improve dose distributions to critical dose-limiting structures near the target. Whether these improved dose distributions are associated with decreased toxicity when compared with conventional three-dimensional treatment remains a subject of investigation. Methods and Materials: 46 patients with pancreatic/ampullary cancer were treated with concurrent chemoradiation (CRT) using inverse-planned IMRT. All patients received CRT based on 5-fluorouracil in a schema similar to Radiation Therapy Oncology Group (RTOG) 97-04. Rates of acute gastrointestinal (GI) toxicity for this series of IMRT-treated patients were compared with those from RTOG 97-04, where all patients were treated with three-dimensional conformal techniques. Chi-square analysis was used to determine if there was a statistically different incidence in acute GI toxicity between these two groups of patients. Results: The overall incidence of Grade 3-4 acute GI toxicity was low in patients receiving IMRT-based CRT. When compared with patients who had three-dimensional treatment planning (RTOG 97-04), IMRT significantly reduced the incidence of Grade 3-4 nausea and vomiting (0% vs. 11%, p = 0.024) and diarrhea (3% vs. 18%, p = 0.017). There was no significant difference in the incidence of Grade 3-4 weight loss between the two groups of patients. Conclusions: IMRT is associated with a statistically significant decrease in acute upper and lower GI toxicity among patients treated with CRT for pancreatic/ampullary cancers. Future clinical trials plan to incorporate the use of IMRT, given that it remains a subject of active investigation.

  9. Dynamic Visual Acuity and Landing Sickness in Crewmembers Returning from Long-Duration Spaceflight

    NASA Technical Reports Server (NTRS)

    Rosenberg, M.J.F; Peters, B.T.; Reschke, M. F.

    2016-01-01

    Long-term exposure to microgravity causes sensorimotor adaptations that result in functional deficits upon returning to a gravitational environment. At landing the vestibular system and the central nervous system, responsible for coordinating head and eye movements, are adapted to microgravity and must re-adapt to the gravitational environment. This re-adaptation causes decrements in gaze control and dynamic visual acuity, with astronauts reporting oscillopsia and blurred vision. Dynamic visual acuity (DVA) is assessed using an oscillating chair developed in the Neuroscience Laboratory at JSC. This chair is lightweight and easily portable for quick deployment in the field. The base of the chair is spring-loaded and allows for manual oscillation of the subject. Using a metronome, the chair is vertically oscillated plus or minus 2 cm at 2 Hz by an operator, to simulate walking. While the subject is being oscillated, they are asked to discern the direction of Landolt-C optotypes of varying sizes and record their direction using a gamepad. The visual acuity thresholds are determined using an algorithm that alters the size of the optotype based on the previous response of the subject using a forced-choice best parameter estimation that is able to rapidly converge on the threshold value. Visual acuity thresholds were determined both for static (seated) and dynamic (oscillating) conditions. Dynamic visual acuity is defined as the difference between the dynamic and static conditions. Dynamic visual acuity measures will be taken prior to flight (typically L-180, L-90, and L-60) and up to eight times after landing, including up to 3 times on R plus 0. Follow up measurements will be taken at R plus 1 (approximately 36 hours after landing). Long-duration International Space Station crewmembers will be tested once at the refueling stop in Europe and once again upon return to Johnson Space Center. In addition to DVA, subjective ratings of motion sickness will be recorded

  10. Assessing the utility of visual acuity measures in visual prostheses.

    PubMed

    Caspi, Avi; Zivotofsky, Ari Z

    2015-03-01

    There are presently several ongoing clinical trials to provide usable sight to profoundly visually impaired patients by means of electrical stimulation of the retina. Some of the blind patients implanted with retinal prosthesis reported un-patterned perception and yet benefit from the device in many activities of daily living, seemingly because they adopt active scanning strategies. The aim of the present work is to evaluate if and under what conditions a measured visual acuity level is truly an indication that the brain perceived a patterned image from the electrical stimulation of the visual prosthesis. Sighted subjects used a pixelized simulator in which they perceived either a low resolution sub-sampling of the original image ("normal mode"--patterned vision) or an image that was solely a function of the brightness and size of the original image ("brightness mode"--no patterned vision). Results show that subjects were able to adopt a head scanning strategy that enabled acuity beyond the resolution set by a static view of the stimulus. In brightness mode, i.e. without patterned vision, most subjects achieved a measurable acuity level better than the limit set by the geometrical resolution of the entire array but worse than the limit set by the distance between neighboring simulated pixels. In normal mode all subject achieved acuity level that is better than the geometrical resolution of the simulated pixels. Thus, visual acuity levels comparable with the electrodes/pixels resolution implies that the patient perceives an image with spatial patterns. PMID:25637855

  11. Effect of Myopic Defocus on Visual Acuity after Phakic Intraocular Lens Implantation and Wavefront-guided Laser in Situ Keratomileusis.

    PubMed

    Kamiya, Kazutaka; Shimizu, Kimiya; Igarashi, Akihito; Kawamorita, Takushi

    2015-01-01

    This study aimed to investigate the effect of myopic defocus on visual acuity after phakic intraocular lens (IOL) implantation and wavefront-guided laser in situ keratomileusis (wfg-LASIK). Our prospective study comprised thirty eyes undergoing posterior chamber phakic IOL implantation and 30 eyes undergoing wfg-LASIK. We randomly measured visual acuity under myopic defocus after cycloplegic and non-cycloplegic correction. We also calculated the modulation transfer function by optical simulation and estimated visual acuity from Campbell &Green's retinal threshold curve. Visual acuity in the phakic IOL group was significantly better than that in the wfg-LASIK group at myopic defocus levels of 0, -1, and -2 D (p < 0.001, p < 0.001, and p = 0.02, Mann-Whitney U-test), but not at a defocus of -3 D (p = 0.30). Similar results were also obtained in a cycloplegic condition. Decimal visual acuity values at a myopic defocus of 0, -1, -2, and -3 D by optical simulation were estimated to be 1.95, 1.21, 0.97, and 0.75 in the phakic IOL group, and 1.39, 1.11, 0.94, and 0.71 in the wfg-LASIK group, respectively. From clinical and optical viewpoints, phakic IOL implantation was superior to wfg-LASIK in terms of the postoperative visual performance, even in the presence of low to moderate myopic regression. PMID:25994984

  12. Significantly improving electromagnetic performance of nanopaper and its shape-memory nanocomposite by aligned carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Lu, Haibao; Gou, Jan

    2012-04-01

    A new nanopaper that exhibits exciting electrical and electromagnetic performances is fabricated by incorporating magnetically aligned carbon nanotube (CNT) with carbon nanofibers (CNFs). Electromagnetic CNTs were blended with and aligned into the nanopaper using a magnetic field, to significantly improve the electrical and electromagnetic performances of nanopaper and its enabled shape-memory polymer (SMP) composite. The morphology and structure of the aligned CNT arrays in nanopaper were characterized with scanning electronic microscopy (SEM). A continuous and compact network of CNFs and aligned CNTs indicated that the nanopaper could have highly conductive properties. Furthermore, the electromagnetic interference (EMI) shielding efficiency of the SMP composites with different weight content of aligned CNT arrays was characterized. Finally, the aligned CNT arrays in nanopapers were employed to achieve the electrical actuation and accelerate the recovery speed of SMP composites.

  13. Novel analogues of the therapeutic complement inhibitor compstatin with significantly improved affinity and potency1

    PubMed Central

    Qu, Hongchang; Magotti, Paola; Ricklin, Daniel; Wu, Emilia L.; Kourtzelis, Ioannis; Wu, You-Qiang; Kaznessis, Yiannis N.; Lambris, John D.

    2010-01-01

    Compstatin is a 13-residue disulfide-bridged peptide that inhibits a key step in the activation of the human complement system. Compstatin and its derivatives have shown great promise for the treatment of many clinical disorders associated with unbalanced complement activity. To obtain more potent compstatin analogues, we have now performed an N-methylation scan of the peptide backbone and amino acid substitutions at position 13. One analogue (Ac-I[CVW(Me)QDW-Sar-AHRC](NMe)I-NH2) displayed a 1,000-fold increase in both potency (IC50=62 nM) and binding affinity for C3b (KD=2.3 nM) over that of the original compstatin. Biophysical analysis using surface plasmon resonance and isothermal titration calorimetry suggests that the improved binding originates from more favorable free conformation and stronger hydrophobic interactions. This study provides a series of significantly improved drug leads for therapeutic applications in complement-related diseases, and offers new insights into the structure-activity relationships of compstatin analogues. PMID:21067811

  14. Significantly improved cyclability of lithium manganese oxide under elevated temperature by an easily oxidized electrolyte additive

    NASA Astrophysics Data System (ADS)

    Zhu, Yunmin; Rong, Haibo; Mai, Shaowei; Luo, Xueyi; Li, Xiaoping; Li, Weishan

    2015-12-01

    Spinel lithium manganese oxide, LiMn2O4, is a promising cathode for lithium ion battery in large-scale applications, because it possesses many advantages compared with currently used layered lithium cobalt oxide (LiCoO2) and olivine phosphate (LiFePO4), including naturally abundant resource, environmental friendliness and high and long work potential plateau. Its poor cyclability under high temperature, however, limits its application. In this work, we report a significant cyclability improvement of LiMn2O4 under elevated temperature by using dimethyl phenylphonite (DMPP) as an electrolyte additive. Charge/discharge tests demonstrate that the application of 0.5 wt.% DMPP yields a capacity retention improvement from 16% to 82% for LiMn2O4 after 200 cycles under 55 °C at 1 C (1C = 148 mAh g-1) between 3 and 4.5 V. Electrochemical and physical characterizations indicate that DMPP is electrochemically oxidized at the potential lower than that for lithium extraction, forming a protective cathode interphase on LiMn2O4, which suppresses the electrolyte decomposition and prevents LiMn2O4 from crystal destruction.

  15. Randomised clinical trial evaluating best-corrected visual acuity and central macular thickness after 532-nm subthreshold laser grid photocoagulation treatment in diabetic macular oedema

    PubMed Central

    Pei-pei, W; Shi-zhou, H; Zhen, T; Lin, L; Ying, L; Jiexiong, O; Wen-bo, Z; Chen-jin, J

    2015-01-01

    Purpose To compare best-corrected visual acuity (BCVA) and central macular thickness (CMT) after 532-nm subthreshold laser grid photocoagulation and threshold laser grid photocoagulation for the treatment of diabetic macular oedema (DME). Patients and methods Twenty-three patients (46 eyes) with binocular DME were enroled in this study. The two eyes of each patient were divided into a subthreshold photocoagulation group and a threshold photocoagulation group. The eyes of the subthreshold group underwent 532-nm patter scan laser system (PASCAL) 50% end point subthreshold laser grid photocoagulation therapy, whereas the threshold photocoagulation group underwent short-pulse grid photocoagulation with a 532-nm PASCAL system. BCVA and CMT were assessed in all patients before treatment, 7 days after treatment, and 1, 3, and 6 months after treatment. Results After grid photocoagulation, the mean BCVA improved in both the subthreshold group, and the threshold group, and the two groups did not differ statistically significantly from each other. Similarly, the macular oedema diminished in both groups after treatment, and the two groups did not differ statistically significantly from each other with regard to CMT. Conclusion Both 532-nm subthreshold laser grid photocoagulation and threshold laser grid photocoagulation can improve the visual acuity and reduce CMT in DME patients. PMID:25697457

  16. Vision-guided ocular growth in a mutant chicken model with diminished visual acuity

    PubMed Central

    Ritchey, Eric R.; Zelinka, Christopher; Tang, Junhua; Liu, Jun; Code, Kimberly A.; Petersen-Jones, Simon; Fischer, Andy J.

    2012-01-01

    Visual experience is known to guide ocular growth. We tested the hypothesis that vision-guided ocular growth is disrupted in a model system with diminished visual acuity. We examine whether ocular elongation is influenced by form-deprivation (FD) and lens-imposed defocus in the Retinopathy, Globe Enlarged (RGE) chicken. Young RGE chicks have poor visual acuity, without significant retinal pathology, resulting from a mutation in guanine nucleotide-binding protein β3 (GNB3), also known as transducin β3 or Gβ3. The mutation in GNB3 destabilizes the protein and causes a loss of Gβ3 from photoreceptors and ON-bipolar cells. (Ritchey et al. 2010)FD increased ocular elongation in RGE eyes in a manner similar to that seen in wild-type (WT) eyes. By comparison, the excessive ocular elongation that results from hyperopic defocus was increased, whereas myopic defocus failed to significantly decrease ocular elongation in RGE eyes. Brief daily periods of unrestricted vision interrupting FD prevented ocular elongation in RGE chicks in a manner similar to that seen in WT chicks. Glucagonergic amacrine cells differentially expressed the immediate early gene Egr1 in response to growth-guiding stimuli in RGE retinas, but the defocus-dependent up-regulation of Egr1 was lesser in RGE retinas compared to that of WT retinas. We conclude that high visual acuity, and the retinal signaling mediated by Gβ3, is not required for emmetropization and the excessive ocular elongation caused by FD and hyperopic defocus. However, the loss of acuity and Gβ3 from RGE retinas causes enhanced responses to hyperopic defocus and diminished responses to myopic defocus. PMID:22824538

  17. Visual Acuity of Simulated Thalamic Visual Prostheses in Normally Sighted Humans

    PubMed Central

    Jeffries, Ailsa; Pezaris, John S.

    2013-01-01

    Simulation in normally sighted individuals is a crucial tool to evaluate the performance of potential visual prosthesis designs prior to human implantation of a device. Here, we investigated the effects of electrode count on visual acuity, learning rate and response time in 16 normally sighted subjects using a simulated thalamic visual prosthesis, providing the first performance reports for thalamic designs. A new letter recognition paradigm using a multiple-optotype two-alternative forced choice task was adapted from the Snellen eye chart, and specifically devised to be readily communicated to both human and non-human primate subjects. Validation of the method against a standard Snellen acuity test in 21 human subjects showed no significant differences between the two tests. The novel task was then used to address three questions about simulations of the center-weighted phosphene patterns typical of thalamic designs: What are the expected Snellen acuities for devices with varying numbers of contacts, do subjects display rapid adaptation to the new visual modality, and can response time in the task provide clues to the mechanisms of perception in low-resolution artificial vision? Population performance (hit rate) was significantly above chance when viewing Snellen 20/200 optotypes (Log MAR 1.0) with 370 phosphenes in the central 10 degrees of vision, ranging to Snellen 20/800 (Log MAR 1.6) with 25 central phosphenes. Furthermore, subjects demonstrated learning within the 1–2 hours of task experience indicating the potential for an effective rehabilitation and possibly better visual performance after a longer period of training. Response time differences suggest that direct letter perception occurred when hit rate was above 75%, whereas a slower strategy like feature-based pattern matching was used in conditions of lower relative resolution. As pattern matching can substantially boost effective acuity, these results suggest post-implant therapy should specifically

  18. Aerodynamic Improvements of an Empty Timber Truck can Have the Potential of Significantly Reducing Fuel Consumption

    NASA Astrophysics Data System (ADS)

    Andersson, Magnus; Marashi, Seyedeh Sepideh; Karlsson, Matts

    2012-11-01

    In the present study, aerodynamic drag (AD) has been estimated for an empty and a fully loaded conceptual timber truck (TT) using Computational Fluid Dynamics (CFD). The increasing fuel prices have challenged heavy duty vehicle (HDV) manufactures to strive for better fuel economy, by e.g. utilizing drag reducing external devices. Despite this knowledge, the TT fleets seem to be left in the dark. Like HDV aerodynamics, similarities can be observed as a large low pressure wake is formed behind the tractor (unloaded) and downstream of the trailer (full load) thus generating AD. As TTs travel half the time without any cargo, focus on drag reduction is important. The full scaled TTs where simulated using the realizable k-epsilon model with grid adaption techniques for mesh independence. Our results indicate that a loaded TT reduces the AD significantly as both wake size and turbulence kinetic energy are lowered. In contrast to HDV the unloaded TTs have a much larger design space available for possible drag reducing devices, e.g. plastic wrapping and/or flaps. This conceptual CFD study has given an indication of the large AD difference between the unloaded and fully loaded TT, showing the potential for significant AD improvements.

  19. Significant improvement in one-dimensional cursor control using Laplacian electroencephalography over electroencephalography

    NASA Astrophysics Data System (ADS)

    Boudria, Yacine; Feltane, Amal; Besio, Walter

    2014-06-01

    Objective. Brain-computer interfaces (BCIs) based on electroencephalography (EEG) have been shown to accurately detect mental activities, but the acquisition of high levels of control require extensive user training. Furthermore, EEG has low signal-to-noise ratio and low spatial resolution. The objective of the present study was to compare the accuracy between two types of BCIs during the first recording session. EEG and tripolar concentric ring electrode (TCRE) EEG (tEEG) brain signals were recorded and used to control one-dimensional cursor movements. Approach. Eight human subjects were asked to imagine either ‘left’ or ‘right’ hand movement during one recording session to control the computer cursor using TCRE and disc electrodes. Main results. The obtained results show a significant improvement in accuracies using TCREs (44%-100%) compared to disc electrodes (30%-86%). Significance. This study developed the first tEEG-based BCI system for real-time one-dimensional cursor movements and showed high accuracies with little training.

  20. SPOT HRVIR: A significant improvement of high resolution visible SPOT camera to i.r. wavelengths

    NASA Astrophysics Data System (ADS)

    Jouan, J.; Reulet, J. F.; Costes, G.

    Since March 1986, the SPOT-HRV cameras are imaging the Earth in a 10 m resolution panchromatic mode and three 20 m resolution spectral modes all in the visible and near infra-red wavelengths. The interest of medium i.r. imaging for observing vegetation has raised in the past and the implementation of a 1.6 μm band was decided by CNES for SPOT 4. New 3000 elements detector matrix had to be developed. This work is nearly completed now through a contract placed at Thomson by CNES. In parallel, the focal plane of the previous HRV cameras has been completely redesigned and the video electronics has also been significantly improved taking into account both some problems identified on SPOT 1 in orbit and the implementation of the MIR band. A significant change in integration and test is introduced by the operating temperature of the MIR detectors to be accurately controlled at 5°C and a calibration of the whole instrument in vacuum is foreseen. Following a presentation of HRV-SPOT 1 main flight results, technical and programmatical points of the SPOT 4 HRVIR situation is presented in the paper.

  1. Human Time-Frequency Acuity Beats the Fourier Uncertainty Principle

    NASA Astrophysics Data System (ADS)

    Oppenheim, Jacob N.; Magnasco, Marcelo O.

    2013-01-01

    The time-frequency uncertainty principle states that the product of the temporal and frequency extents of a signal cannot be smaller than 1/(4π). We study human ability to simultaneously judge the frequency and the timing of a sound. Our subjects often exceeded the uncertainty limit, sometimes by more than tenfold, mostly through remarkable timing acuity. Our results establish a lower bound for the nonlinearity and complexity of the algorithms employed by our brains in parsing transient sounds, rule out simple “linear filter” models of early auditory processing, and highlight timing acuity as a central feature in auditory object processing.

  2. Brief report: the relationship between visual acuity, the embedded figures test and systemizing in autism spectrum disorders.

    PubMed

    Brosnan, Mark J; Gwilliam, Lucy R; Walker, Ian

    2012-11-01

    Enhanced performance upon the Embedded Figures Test (EFT) in individuals with autism spectrum disorder (ASD) has informed psychological theories of the non-social aspects that characterise ASD. The Extreme Male Brain theory of autism proposes that enhanced visual acuity underpins greater attention to detail (assessed by the EFT) which is a prerequisite for Systemizing. To date, however, no study has empirically examined these relationships. 13 males with ASD and 13 male controls were assessed upon tasks argued to reflect these levels of processing. The ASD group were found to have significantly greater visual acuity, EFT performance and Systemizing ability than the control group. However, regression analysis revealed that the strongest relationship was between visual acuity and EFT performance. PMID:22450702

  3. Testing vision testing: quantifying the effect of movement on visual acuity measurement

    PubMed Central

    Tidbury, L P; O'Connor, A R

    2015-01-01

    Purpose Assessment of visual acuity (VA) has been shown to vary between tests, which may be attributable in part to test inaccuracies, such as a change in the distance between the chart and subject. Therefore, the study aim was to quantify changes in chart/patient separation during near and distance VA testing, and to analyse the relationship between VA and movement observed. Methods Volunteer orthoptists and subjects were filmed during near and distance VA testing, with the amount of movement determined from the recording. Controlling for movement using chin rests and chart stands, VA was retested. Actual changes in VA due to a change in subject or chart movement were compared with theoretical predictions. Results Fifty-one subjects (18–73 years) were assessed. Median (interquartile) movements of 0.06 m (0.07) towards and 0.11 m (0.08) away from the chart were measured (maximum 0.17 m towards and 0.24 m away). Significant differences in VA score were measured when movement was restricted, at near and distance (P<0.05). VA score change agreed with predicted values in 67% of the cases, however, reduced test distance during near vision testing resulted in a degradation of VA, opposite to the improvement expected. Conclusion There were significant variations in subject/chart separation during testing, which could have affected VA values. While this movement is associated with a change in VA, additional factors to movement appear to influence the score achieved during near testing. Procedures to minimise variation, by eliminating movement of test chart or subject, will improve VA test accuracy. PMID:25341437

  4. Significantly Improving Regional Seismic Amplitude Tomography at Higher Frequencies by Determining S -Wave Bandwidth

    DOE PAGESBeta

    Fisk, Mark D.; Pasyanos, Michael E.

    2016-05-03

    Characterizing regional seismic signals continues to be a difficult problem due to their variability. Calibration of these signals is very important to many aspects of monitoring underground nuclear explosions, including detecting seismic signals, discriminating explosions from earthquakes, and reliably estimating magnitude and yield. Amplitude tomography, which simultaneously inverts for source, propagation, and site effects, is a leading method of calibrating these signals. A major issue in amplitude tomography is the data quality of the input amplitude measurements. Pre-event and prephase signal-to-noise ratio (SNR) tests are typically used but can frequently include bad signals and exclude good signals. The deficiencies ofmore » SNR criteria, which are demonstrated here, lead to large calibration errors. To ameliorate these issues, we introduce a semi-automated approach to assess the bandwidth of a spectrum where it behaves physically. We determine the maximum frequency (denoted as Fmax) where it deviates from this behavior due to inflections at which noise or spurious signals start to bias the spectra away from the expected decay. We compare two amplitude tomography runs using the SNR and new Fmax criteria and show significant improvements to the stability and accuracy of the tomography output for frequency bands higher than 2 Hz by using our assessments of valid S-wave bandwidth. We compare Q estimates, P/S residuals, and some detailed results to explain the improvements. Lastly, for frequency bands higher than 4 Hz, needed for effective P/S discrimination of explosions from earthquakes, the new bandwidth criteria sufficiently fix the instabilities and errors so that the residuals and calibration terms are useful for application.« less

  5. Improved bowel preparation increases polyp detection and unmasks significant polyp miss rate

    PubMed Central

    Papanikolaou, Ioannis S; Sioulas, Athanasios D; Magdalinos, Nektarios; Beintaris, Iosif; Lazaridis, Lazaros-Dimitrios; Polymeros, Dimitrios; Malli, Chrysoula; Dimitriadis, George D; Triantafyllou, Konstantinos

    2015-01-01

    AIM: To retrospectively compare previous-day vs split-dose preparation in terms of bowel cleanliness and polyp detection in patients referred for polypectomy. METHODS: Fifty patients underwent two colonoscopies: one diagnostic in a private clinic and a second for polypectomy in a University Hospital. The latter procedures were performed within 12 wk of the index ones. Examinations were accomplished by two experienced endoscopists, different in each facility. Twenty-seven patients underwent screening/surveillance colonoscopy, while the rest were symptomatic. Previous day bowel preparation was utilized initially and split-dose for polypectomy. Colon cleansing was evaluated using the Aronchick scale. We measured the number of detected polyps, and the polyp miss rates per-polyp. RESULTS: Excellent/good preparation was reported in 38 cases with previous-day preparation (76%) vs 46 with split-dose (92%), respectively (P = 0.03). One hundred and twenty-six polyps were detected initially and 169 subsequently (P < 0.0001); 88 vs 126 polyps were diminutive (P < 0.0001), 25 vs 29 small (P = 0.048) and 13 vs 14 equal or larger than 10 mm. The miss rates for total, diminutive, small and large polyps were 25.4%, 30.1%, 13.7% and 6.6%, respectively. Multivariate analysis revealed that split-dose preparation was significantly associated (OR, P) with increased number of polyps detected overall (0.869, P < 0.001), in the right (0.418, P = 0.008) and in the left colon (0.452, P = 0.02). CONCLUSION: Split-dose preparation improved colon cleansing, enhanced polyp detection and unmasked significant polyp miss rates. PMID:26488024

  6. Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognition in urban children

    PubMed Central

    Calderón-Garcidueñas, Lilian; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Cross, Janet V.; Engle, Randall; Aragón-Flores, Mariana; Gómez-Garza, Gilberto; Jewells, Valerie; Weili, Lin; Medina-Cortina, Humberto; Solorio, Edelmira; Chao, Chih-kai; Zhu, Hongtu; Mukherjee, Partha S.; Ferreira-Azevedo, Lara; Torres-Jardón, Ricardo; D'Angiulli, Amedeo

    2013-01-01

    Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9–24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases. PMID:23986703

  7. Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognition in urban children.

    PubMed

    Calderón-Garcidueñas, Lilian; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Cross, Janet V; Engle, Randall; Aragón-Flores, Mariana; Gómez-Garza, Gilberto; Jewells, Valerie; Medina-Cortina, Humberto; Solorio, Edelmira; Chao, Chih-Kai; Zhu, Hongtu; Mukherjee, Partha S; Ferreira-Azevedo, Lara; Torres-Jardón, Ricardo; D'Angiulli, Amedeo

    2013-01-01

    Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9-24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases. PMID:23986703

  8. Association of Visual Acuity and Cognitive Impairment in Older Individuals: Fujiwara-kyo Eye Study

    PubMed Central

    Mine, Masashi; Miyata, Kimie; Morikawa, Masayuki; Nishi, Tomo; Okamoto, Nozomi; Kawasaki, Ryo; Yamashita, Hidetoshi; Kurumatani, Norio; Ogata, Nahoko

    2016-01-01

    Abstract Both visual impairment and cognitive impairment are essential factors that determine the quality of life in the aged population. The aim of this study was to determine if a correlation existed between visual acuity and cognitive impairment in an elderly Japanese population. The Fujiwara-kyo Eye Study was a cross-sectional study of individuals aged ≥68 years who lived in Nara Prefecture of Japan. Participants underwent ophthalmological examinations and cognitive function test. A mild visual impairment was defined as having a best corrected visual acuity (BCVA) >0.2 logarithm of the minimum angle of resolution (logMAR) units in the better eye. Cognitive impairment was defined as having a Mini-Mental State Examination (MMSE) score of ≤23 points. A total to 2818 individuals completed the examinations. The mean age of the participants was 76.3 ± 4.8 years (mean ± standard deviation). The mean BCVA of the better eye was −0.02 ± 0.13 logMAR units and 6.6% subjects were classified as being mildly visually impaired. The mean MMSE score was 27.3 ± 2.3 and 5.7% subjects were classified as being cognitively impaired. The proportion of subjects with cognitive or moderate visual impairment increased with age, and there was a significant correlation between the visual acuity and MMSE score (r = −0.10, p < 0.0001). Subjects with mild visual impairments had 2.4 times higher odds of having cognitive impairment than those without visual impairment (odds ratio 2.4, 95% confidence interval, 1.5–3.8, p < 0.001) after adjusting for age, sex, and length of education. We conclude that it may be important to maintain good visual acuity to reduce the risk of having cognitive impairment. PMID:27610269

  9. Association of Visual Acuity and Cognitive Impairment in Older Individuals: Fujiwara-kyo Eye Study.

    PubMed

    Mine, Masashi; Miyata, Kimie; Morikawa, Masayuki; Nishi, Tomo; Okamoto, Nozomi; Kawasaki, Ryo; Yamashita, Hidetoshi; Kurumatani, Norio; Ogata, Nahoko

    2016-01-01

    Both visual impairment and cognitive impairment are essential factors that determine the quality of life in the aged population. The aim of this study was to determine if a correlation existed between visual acuity and cognitive impairment in an elderly Japanese population. The Fujiwara-kyo Eye Study was a cross-sectional study of individuals aged ≥68 years who lived in Nara Prefecture of Japan. Participants underwent ophthalmological examinations and cognitive function test. A mild visual impairment was defined as having a best corrected visual acuity (BCVA) >0.2 logarithm of the minimum angle of resolution (logMAR) units in the better eye. Cognitive impairment was defined as having a Mini-Mental State Examination (MMSE) score of ≤23 points. A total to 2818 individuals completed the examinations. The mean age of the participants was 76.3 ± 4.8 years (mean ± standard deviation). The mean BCVA of the better eye was -0.02 ± 0.13 logMAR units and 6.6% subjects were classified as being mildly visually impaired. The mean MMSE score was 27.3 ± 2.3 and 5.7% subjects were classified as being cognitively impaired. The proportion of subjects with cognitive or moderate visual impairment increased with age, and there was a significant correlation between the visual acuity and MMSE score (r = -0.10, p < 0.0001). Subjects with mild visual impairments had 2.4 times higher odds of having cognitive impairment than those without visual impairment (odds ratio 2.4, 95% confidence interval, 1.5-3.8, p < 0.001) after adjusting for age, sex, and length of education. We conclude that it may be important to maintain good visual acuity to reduce the risk of having cognitive impairment. PMID:27610269

  10. Development of significantly improved catalysts for coal liquefaction and upgrading of coal extracts

    SciTech Connect

    Sinha, V.T.; Kutzenco, P.D.; Preston, W.J.; Brinen, J.S.; Graham, S.W.; Butensky, M.; Muchnick, T.L.; Hyman, D.

    1982-01-01

    During 1979-80, a new generation of very active, long-lived catlaysts for hydrotrating was discovered at the Stamford Research Laboratories of the American Cyanamid Company. The catalysts are based on a unique substrate prepared in bead form from a rehydratable alumina. Their spherical shape, crush strength, and abrasion resistance seem ideally suited for the ebullated bed reactors used in the H-COAL process developed by Hydrocarbon Research, Inc. (HRI). The beads have internal pore structures that are controllable over a wider range than conventional alumina supports, leading to active catalysts that are resistant to poisoning. In September, 1981, the Department of Energy granted a 3-year contract to the American Cyanamid Company for the development of significantly improved catalysts for coal liquefaction anf for upgrading coal extracts, particularly in reactors used in the H-COAL process. Catalysts will first be screened in a batch reactor to identify promising candidated. The latter will be tested in a continuous aging reactor to evaluate their resistance to deactivation under col-liquefaction and extract upgrading conditions. Cold flow ebullation tests of catalysts of different head size are presented, along with some screening and crying of experimental catalysts. Spherical methods for examining catalysts are described.

  11. Activation of Big Grain1 significantly improves grain size by regulating auxin transport in rice

    PubMed Central

    Liu, Linchuan; Tong, Hongning; Xiao, Yunhua; Che, Ronghui; Xu, Fan; Hu, Bin; Liang, Chengzhen; Chu, Jinfang; Li, Jiayang; Chu, Chengcai

    2015-01-01

    Grain size is one of the key factors determining grain yield. However, it remains largely unknown how grain size is regulated by developmental signals. Here, we report the identification and characterization of a dominant mutant big grain1 (Bg1-D) that shows an extra-large grain phenotype from our rice T-DNA insertion population. Overexpression of BG1 leads to significantly increased grain size, and the severe lines exhibit obviously perturbed gravitropism. In addition, the mutant has increased sensitivities to both auxin and N-1-naphthylphthalamic acid, an auxin transport inhibitor, whereas knockdown of BG1 results in decreased sensitivities and smaller grains. Moreover, BG1 is specifically induced by auxin treatment, preferentially expresses in the vascular tissue of culms and young panicles, and encodes a novel membrane-localized protein, strongly suggesting its role in regulating auxin transport. Consistent with this finding, the mutant has increased auxin basipetal transport and altered auxin distribution, whereas the knockdown plants have decreased auxin transport. Manipulation of BG1 in both rice and Arabidopsis can enhance plant biomass, seed weight, and yield. Taking these data together, we identify a novel positive regulator of auxin response and transport in a crop plant and demonstrate its role in regulating grain size, thus illuminating a new strategy to improve plant productivity. PMID:26283354

  12. Significant effect of Ca2+ on improving the heat resistance of lactic acid bacteria.

    PubMed

    Huang, Song; Chen, Xiao Dong

    2013-07-01

    The heat resistance of lactic acid bacteria (LAB) has been extensively investigated due to its highly practical significance. Reconstituted skim milk (RSM) has been found to be one of the most effective protectant wall materials for microencapsulating microorganisms during convective drying, such as spray drying. In addition to proteins and carbohydrate, RSM is rich in calcium. It is not clear which component is critical in the RSM protection mechanism. This study investigated the independent effect of calcium. Ca(2+) was added to lactose solution to examine its influence on the heat resistance of Lactobacillus rhamnosus ZY, Lactobacillus casei Zhang, Lactobacillus plantarum P8 and Streptococcus thermophilus ND03. The results showed that certain Ca(2+) concentrations enhanced the heat resistance of the LAB strains to different extents, that is produced higher survival and shorter regrowth lag times of the bacterial cells. In some cases, the improvements were dramatic. More scientifically insightful and more intensive instrumental study of the Ca(2+) behavior around and in the cells should be carried out in the near future. In the meantime, this work may lead to the development of more cost-effective wall materials with Ca(2+) added as a prime factor. PMID:23617813

  13. Activation of Big Grain1 significantly improves grain size by regulating auxin transport in rice.

    PubMed

    Liu, Linchuan; Tong, Hongning; Xiao, Yunhua; Che, Ronghui; Xu, Fan; Hu, Bin; Liang, Chengzhen; Chu, Jinfang; Li, Jiayang; Chu, Chengcai

    2015-09-01

    Grain size is one of the key factors determining grain yield. However, it remains largely unknown how grain size is regulated by developmental signals. Here, we report the identification and characterization of a dominant mutant big grain1 (Bg1-D) that shows an extra-large grain phenotype from our rice T-DNA insertion population. Overexpression of BG1 leads to significantly increased grain size, and the severe lines exhibit obviously perturbed gravitropism. In addition, the mutant has increased sensitivities to both auxin and N-1-naphthylphthalamic acid, an auxin transport inhibitor, whereas knockdown of BG1 results in decreased sensitivities and smaller grains. Moreover, BG1 is specifically induced by auxin treatment, preferentially expresses in the vascular tissue of culms and young panicles, and encodes a novel membrane-localized protein, strongly suggesting its role in regulating auxin transport. Consistent with this finding, the mutant has increased auxin basipetal transport and altered auxin distribution, whereas the knockdown plants have decreased auxin transport. Manipulation of BG1 in both rice and Arabidopsis can enhance plant biomass, seed weight, and yield. Taking these data together, we identify a novel positive regulator of auxin response and transport in a crop plant and demonstrate its role in regulating grain size, thus illuminating a new strategy to improve plant productivity. PMID:26283354

  14. An extended bioreaction database that significantly improves reconstruction and analysis of genome-scale metabolic networks.

    PubMed

    Stelzer, Michael; Sun, Jibin; Kamphans, Tom; Fekete, Sándor P; Zeng, An-Ping

    2011-11-01

    The bioreaction database established by Ma and Zeng (Bioinformatics, 2003, 19, 270-277) for in silico reconstruction of genome-scale metabolic networks has been widely used. Based on more recent information in the reference databases KEGG LIGAND and Brenda, we upgrade the bioreaction database in this work by almost doubling the number of reactions from 3565 to 6851. Over 70% of the reactions have been manually updated/revised in terms of reversibility, reactant pairs, currency metabolites and error correction. For the first time, 41 spontaneous sugar mutarotation reactions are introduced into the biochemical database. The upgrade significantly improves the reconstruction of genome scale metabolic networks. Many gaps or missing biochemical links can be recovered, as exemplified with three model organisms Homo sapiens, Aspergillus niger, and Escherichia coli. The topological parameters of the constructed networks were also largely affected, however, the overall network structure remains scale-free. Furthermore, we consider the problem of computing biologically feasible shortest paths in reconstructed metabolic networks. We show that these paths are hard to compute and present solutions to find such paths in networks of small and medium size. PMID:21952610

  15. PERSPECTIVE: Is acuity enough? Other considerations in clinical investigations of visual prostheses

    NASA Astrophysics Data System (ADS)

    Lepri, Bernard P.

    2009-06-01

    Visual impairing eye diseases are the major frontier facing ophthalmic research today in light of our rapidly aging population. The visual skills necessary for improving the quality of daily function and life are inextricably linked to these impairing diseases. Both research and reimbursement programs are emphasizing outcome-based results. Is improvement in visual acuity alone enough to improve the function and quality of life of visually impaired persons? This perspective summarizes the types of effectiveness endpoints for clinical investigations of visual prostheses that go beyond visual acuity. The clinical investigation of visual prostheses should include visual function, functional vision and quality of life measures. Specifically, they encompass contrast sensitivity, orientation and mobility, activities of daily living and quality of life assessments. The perspective focuses on the design of clinical trials for visual prostheses and the methods of determining effectiveness above and beyond visual acuity that will yield outcomes that are measured by improved function in the visual world and quality of life. The visually impaired population is the primary consideration in this presentation with particular emphases on retinitis pigmentosa and age-related macular degeneration. Clinical trials for visual prostheses cannot be isolated from the need for medical rehabilitation in order to obtain measurements of effectiveness that produce outcomes/evidence-based success. This approach will facilitate improvement in daily function and quality of life of patients with diseases that cause chronic vision impairment. The views and opinions are those of the author and do not necessarily reflect those of the US Food and Drug Administration, the US Department of Health and Human Services or the Public Health Service.

  16. Astronaut Charles Conrad during visual acuity experiments over Laredo

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Astronaut Charles Conrad Jr., pilot for the prime crew on the Gemini 5 space flight, takes pictures of predetermined land areas during visual acuity experiments over Laredo, Texas. The experiments will aid in learning to identify known terrestrial features under controlled conditions.

  17. Astronauts Cooper and Conrad prepare cameras during visual acuity tests

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Astronauts L. Gordon Cooper Jr. (left), command pilot, and Charles Conrad Jr., pilot, the prime crew of the Gemini 5 space flight, prepare their cameras while aboard a C-130 aircraft flying near Laredo. The two astronauts are taking part in a series of visual acuity experiments to aid them in learning to identify known terrestrial features under controlled conditions.

  18. The Approximate Number System Acuity Redefined: A Diffusion Model Approach

    PubMed Central

    Park, Joonkoo; Starns, Jeffrey J.

    2015-01-01

    While all humans are capable of non-verbally representing numerical quantity using so-called the approximate number system (ANS), there exist considerable individual differences in its acuity. For example, in a non-symbolic number comparison task, some people find it easy to discriminate brief presentations of 14 dots from 16 dots while others do not. Quantifying individual ANS acuity from such a task has become an essential practice in the field, as individual differences in such a primitive number sense is thought to provide insights into individual differences in learned symbolic math abilities. However, the dominant method of characterizing ANS acuity—computing the Weber fraction (w)—only utilizes the accuracy data while ignoring response times (RT). Here, we offer a novel approach of quantifying ANS acuity by using the diffusion model, which accounts both accuracy and RT distributions. Specifically, the drift rate in the diffusion model, which indexes the quality of the stimulus information, is used to capture the precision of the internal quantity representation. Analysis of behavioral data shows that w is contaminated by speed-accuracy tradeoff, making it problematic as a measure of ANS acuity, while drift rate provides a measure more independent from speed-accuracy criterion settings. Furthermore, drift rate is a better predictor of symbolic math ability than w, suggesting a practical utility of the measure. These findings demonstrate critical limitations of the use of w and suggest clear advantages of using drift rate as a measure of primitive numerical competence. PMID:26733929

  19. Readers' Trust, Socio-Demographic, and Acuity Influences in Citizen Journalism Credibility for Disrupted Online Newspapers

    ERIC Educational Resources Information Center

    Wester, Aaron Micah

    2013-01-01

    The purpose of this quantitative research study was to evaluate and determine if significant associations and linear correlations exist between reader socio-demographics, levels of trust and affinity in online citizen writer news story article content, brand loyalty, and acuity in newspaper organizations transitioning from print to online in a…

  20. Gap Detection and Temporal Modulation Transfer Function as Behavioral Estimates of Auditory Temporal Acuity Using Band-Limited Stimuli in Young and Older Adults

    PubMed Central

    Shen, Yi

    2015-01-01

    Purpose Gap detection and the temporal modulation transfer function (TMTF) are 2 common methods to obtain behavioral estimates of auditory temporal acuity. However, the agreement between the 2 measures is not clear. This study compares results from these 2 methods and their dependencies on listener age and hearing status. Method Gap detection thresholds and the parameters that describe the TMTF (sensitivity and cutoff frequency) were estimated for young and older listeners who were naive to the experimental tasks. Stimuli were 800-Hz-wide noises with upper frequency limits of 2400 Hz, presented at 85 dB SPL. A 2-track procedure (Shen & Richards, 2013) was used for the efficient estimation of the TMTF. Results No significant correlation was found between gap detection threshold and the sensitivity or the cutoff frequency of the TMTF. No significant effect of age and hearing loss on either the gap detection threshold or the TMTF cutoff frequency was found, while the TMTF sensitivity improved with increasing hearing threshold and worsened with increasing age. Conclusion Estimates of temporal acuity using gap detection and TMTF paradigms do not seem to provide a consistent description of the effects of listener age and hearing status on temporal envelope processing. PMID:25087722

  1. Using gas modifiers to significantly improve sensitivity and selectivity in a cylindrical FAIMS device.

    PubMed

    Purves, Randy W; Ozog, Allison R; Ambrose, Stephen J; Prasad, Satendra; Belford, Michael; Dunyach, Jean-Jacques

    2014-07-01

    Recent reports describing enhanced performance when using gas additives in a DMS device (planar electrodes) have indicated that comparable benefits are not attainable using FAIMS (cylindrical electrodes), owing to the non-homogeneous electric fields within the analyzer region. In this study, a FAIMS system (having cylindrical electrodes) was modified to allow for controlled delivery of gas additives. An experiment was carried out that illustrates the important distinction between gas modifiers present as unregulated contaminants and modifiers added in a controlled manner. The effect of contamination was simulated by adjusting the ESI needle position to promote incomplete desolvation, thereby permitting ESI solvent vapor into the FAIMS analyzer region, causing signal instability and irreproducible CV values. However, by actively controlling the delivery of the gas modifier, reproducible CV spectra were obtained. The effects of adding different gas modifiers were examined using 15 positive ions having mass-to-charge (m/z) values between 90 and 734. Significant improvements in peak capacity and increases in ion transmission were readily attained by adding acetonitrile vapor, even at trace levels (≤0.1%). Increases in signal intensity were greatest for the low m/z ions; for the six lowest molecular weight species, signal intensities increased by ∼10- to over 100-fold compared with using nitrogen without gas additives, resulting in equivalent or better signal intensities compared with ESI without FAIMS. These results confirm that analytical benefits derived from the addition of gas modifiers reported with a uniform electric field (DMS) also are observed using a non-homogenous electric field (FAIMS) in the analyser region. PMID:24796261

  2. Significant contribution of realistic vegetation representation to improved simulation and prediction of climate anomalies over land

    NASA Astrophysics Data System (ADS)

    Alessandri, Andrea; Catalano, Franco; De Felice, Matteo; Doblas-Reyes, Francisco; van den Hurk, Bart; Miller, Paul

    2015-04-01

    The EC-Earth earth system model has been recently developed to include the dynamics of vegetation through the coupling with the LPJ-Guess model. In its original formulation, the coupling between atmosphere and vegetation variability is simply operated by the vegetation Leaf Area Index (LAI), which affects climate by only changing the vegetation physiological resistance to evapotranspiration. This coupling with no implied change of the vegetation fractional coverage has been reported to have a weak effect on the surface climate modeled by EC-Earth (e.g.: also Weiss et al. 2012). The effective sub-grid vegetation fractional coverage can vary seasonally and at interannual time-scales as a function of leaf-canopy growth, phenology and senescence, and therefore affect biophysical parameters such as the surface roughness, albedo and soil field capacity. To adequately represent this effect in EC-Earth, we included an exponential dependence of the vegetation densitiy to the LAI, based on a Lambert-Beer formulation. By comparing historical 20th century simulations and retrospective forecasts performed applying the new effective fractional-coverage parameterization with the respective reference simulations using the original constant vegetation-fraction, we showed an increased effect of vegetation on the EC-Earth surface climate. The analysis shows considerable sensitivity of EC-Earth surface climate at seasonal to interannual time-scales due to the variability of vegetation effective fractional coverage. Particularly large effects are shown over boreal winter middle-to-high latitudes, where the cooling effect of the new parameterization corrects the warm biases of the control simulations over land. For boreal winter, the realistic representation of vegetation variability leads to a significant improvement of the skill in predicting surface climate over land at seasonal time-scales. A potential predictability experiment extended to longer time-scales also indicates the

  3. An optimized procedure for plant recovery from somatic embryos significantly facilitates the genetic improvement of Vitis.

    PubMed

    Li, Zhijian T; Kim, Kyung-Hee; Dhekney, Sadanand A; Jasinski, Jonathan R; Creech, Matthew R; Gray, Dennis J

    2014-01-01

    Plant regeneration from grapevine (Vitis spp.) via somatic embryogenesis typically is poor. Recovery of plants from Vitis rotundifolia Michx. (muscadine grape) is particularly problematic due to extremely low efficiency, including extended culture durations required for embryo-plant conversion. Poor plant recovery is an obstacle to the selection of improved genetically modified lines. Somatic embryos (SEs) of V. rotundifolia cultivar Delicious (Del-HS) and Vitis vinifera L cultivar Thompson Seedless (TS) were used to identify culture media and conditions that promoted embryo differentiation and plant conversion; this resulted in a two-step culture system. In comparative culture experiments, C2D medium containing 6% sucrose was the most effective, among four distinct formulae tested, for inducing precocious SE germination and cell differentiation. This medium, further supplemented with 4 µM 6-benzylaminopurine (C2D4B), was subsequently determined to enhance post-germinative growth of SE. MS medium supplemented with 0.5 µM 1-naphthaleneacetic acid (MSN) was then utilized to stimulate root and shoot growth of germinated SE. An average of 35% and 80% 'Del-HS' and 'TS' SE, respectively, developed into plants. All plants developed robust root and shoot systems and exhibited excellent survival following transfer to soil. Over 150 plants of 'Del-HS' were regenerated and established within 2.5 months, which is a dramatic reduction from the 6- to 12-month time period previously required. Similarly, 88 'TS' plant lines were obtained within the same time period. Subsequently, seven out of eight Vitis cultivars exhibited significantly increased plant conversion percentages, demonstrating broad application of the two-step culture system to produce the large numbers of independent plant lines needed for selection of desired traits. PMID:26504540

  4. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions

    PubMed Central

    Hengl, Tomislav; Heuvelink, Gerard B. M.; Kempen, Bas; Leenaars, Johan G. B.; Walsh, Markus G.; Shepherd, Keith D.; Sila, Andrew; MacMillan, Robert A.; Mendes de Jesus, Jorge; Tamene, Lulseged; Tondoh, Jérôme E.

    2015-01-01

    80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008–2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management—organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na). We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15–75% in Root Mean Squared Error (RMSE) across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols) help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring pedological

  5. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions.

    PubMed

    Hengl, Tomislav; Heuvelink, Gerard B M; Kempen, Bas; Leenaars, Johan G B; Walsh, Markus G; Shepherd, Keith D; Sila, Andrew; MacMillan, Robert A; Mendes de Jesus, Jorge; Tamene, Lulseged; Tondoh, Jérôme E

    2015-01-01

    80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management--organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na). We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15-75% in Root Mean Squared Error (RMSE) across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols) help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring pedological

  6. An optimized procedure for plant recovery from somatic embryos significantly facilitates the genetic improvement of Vitis

    PubMed Central

    Li, Zhijian T; Kim, Kyung-Hee; Dhekney, Sadanand A; Jasinski, Jonathan R; Creech, Matthew R; Gray, Dennis J

    2014-01-01

    Plant regeneration from grapevine (Vitis spp.) via somatic embryogenesis typically is poor. Recovery of plants from Vitis rotundifolia Michx. (muscadine grape) is particularly problematic due to extremely low efficiency, including extended culture durations required for embryo–plant conversion. Poor plant recovery is an obstacle to the selection of improved genetically modified lines. Somatic embryos (SEs) of V. rotundifolia cultivar Delicious (Del-HS) and Vitis vinifera L cultivar Thompson Seedless (TS) were used to identify culture media and conditions that promoted embryo differentiation and plant conversion; this resulted in a two-step culture system. In comparative culture experiments, C2D medium containing 6% sucrose was the most effective, among four distinct formulae tested, for inducing precocious SE germination and cell differentiation. This medium, further supplemented with 4 µM 6-benzylaminopurine (C2D4B), was subsequently determined to enhance post-germinative growth of SE. MS medium supplemented with 0.5 µM 1-naphthaleneacetic acid (MSN) was then utilized to stimulate root and shoot growth of germinated SE. An average of 35% and 80% ‘Del-HS’ and ‘TS’ SE, respectively, developed into plants. All plants developed robust root and shoot systems and exhibited excellent survival following transfer to soil. Over 150 plants of ‘Del-HS’ were regenerated and established within 2.5 months, which is a dramatic reduction from the 6- to 12-month time period previously required. Similarly, 88 ‘TS’ plant lines were obtained within the same time period. Subsequently, seven out of eight Vitis cultivars exhibited significantly increased plant conversion percentages, demonstrating broad application of the two-step culture system to produce the large numbers of independent plant lines needed for selection of desired traits. PMID:26504540

  7. Waste Minimization Improvements Achieved Through Six Sigma Analysis Result In Significant Cost Savings

    SciTech Connect

    Mousseau, Jeffrey, D.; Jansen, John, R.; Janke, David, H.; Plowman, Catherine, M.

    2003-02-26

    Improved waste minimization practices at the Department of Energy's (DOE) Idaho National Engineering and Environmental Laboratory (INEEL) are leading to a 15% reduction in the generation of hazardous and radioactive waste. Bechtel, BWXT Idaho, LLC (BBWI), the prime management and operations contractor at the INEEL, applied the Six Sigma improvement process to the INEEL Waste Minimization Program to review existing processes and define opportunities for improvement. Our Six Sigma analysis team: composed of an executive champion, process owner, a black belt and yellow belt, and technical and business team members used this statistical based process approach to analyze work processes and produced ten recommendations for improvement. Recommendations ranged from waste generator financial accountability for newly generated waste to enhanced employee recognition programs for waste minimization efforts. These improvements have now been implemented to reduce waste generation rates and are producing positive results.

  8. [Prediction of postoperative visual acuity in retinal detachment with macular involvement].

    PubMed

    Yasukawa, T; Fukuda, T; Kishimoto, M; Ogura, Y

    1995-03-01

    We used laser interferometry (LI) and a potential acuity meter (PAM) to predict visual acuity after surgery for patients with rhegmatogenous retinal detachment with macular involvement. Thirty one eyes of 31 patients with retinal detachment were treated with scleral buckling procedures. Postoperative visual acuity was correlated with preoperative measurements of the LI and PAM, preoperative visual acuity by Landort's ring, and the estimated duration of macular detachment. The correlation between the duration of macular detachment and the postoperative visual acuity was not good (r = 0.55, p < 0.01). Although the preoperative visual acuity showed a relatively good correlation with postoperative visual acuity (r = 0.62, p < 0.01), the results of the LI and PAM provided a better correlation (LI; r = 0.73, PAM; r = 0.71). Our results suggest that the LI and PAM are useful to predict the visual acuity after retinal reattachment in patients with preoperative macular detachment. PMID:7732924

  9. Maturation of visual acuity is accelerated in breast-fed term infants fed baby food containing DHA-enriched egg yolk.

    PubMed

    Hoffman, Dennis R; Theuer, Richard C; Castañeda, Yolanda S; Wheaton, Dianna H; Bosworth, Rain G; O'Connor, Anna R; Morale, Sarah E; Wiedemann, Lindsey E; Birch, Eileen E

    2004-09-01

    Between 6 and 12 mo of age, blood levels of the (n-3) long-chain PUFA, docosahexaenoic acid (DHA), in breast-fed infants typically decrease due to diminished maternal DHA stores and the introduction of DHA-poor solid foods displacing human milk as the primary source of nutrition. Thus, we utilized a randomized, clinical trial format to evaluate the effect of supplemental DHA in solid foods on visual development of breast-fed infants with the primary outcome, sweep visual-evoked potential (VEP) acuity, as an index for maturation of the retina and visual cortex. At 6 mo of age, breast-fed infants were randomly assigned to receive 1 jar (113 g)/d of baby food containing egg yolk enriched with DHA (115 mg DHA/100 g food; n = 25) or control baby food (0 mg DHA; n = 26). Gravimetric measures were used to estimate the supplemental DHA intake which was 83 mg DHA/d in the supplemented group and 0 mg/d in controls. Although many infants in both groups continued to breast-feed for a mean of 9 mo, RBC DHA levels decreased significantly between 6 and 12 mo (from 3.8 to 3.0 g/100 g total fatty acids) in control infants, whereas RBC DHA levels increased by 34% from 4.1 to 5.5 g/100 g by 12 mo in supplemented infants. VEP acuity at 6 mo was 0.49 logMAR (minimum angle of resolution) and improved to 0.29 logMAR by 12 mo in controls. In DHA-supplemented infants, VEP acuity was 0.48 logMAR at 6 mo and matured to 0.14 logMAR at 12 mo (1.5 lines on the eye chart better than controls). At 12 mo, the difference corresponded to 1.5 lines on the eye chart. RBC DHA levels and VEP acuity at 12 mo were correlated (r = -0.50; P = 0.0002), supporting the need of an adequate dietary supply of DHA throughout 1 y of life for neural development. PMID:15333721

  10. A Review of New and Developing Technology to Significantly Improve Mars Sample-Return Missions

    NASA Technical Reports Server (NTRS)

    Carsey, F.; Brophy, J.; Gilmore, M.; Rodgers, D.; Wilcox, B.

    2000-01-01

    A JPL development activity was initiated in FY 1999 for the purpose of examining and evaluating technologies that could materially improve future (i.e., beyond the 2005 launch) Mars sample return missions. The scope of the technology review was comprehensive and end-to-end; the goal was to improve mass, cost, risk, and scientific return. A specific objective was to assess approaches to sample return with only one Earth launch. While the objective of the study was specifically for sample-return, in-situ missions can also benefit from using many of the technologies examined.

  11. Panic attacks and interoceptive acuity for cardiac sensations.

    PubMed

    Asmundson, G J; Sandler, L S; Wilson, K G; Norton, G R

    1993-02-01

    It has been suggested that perception of visceral changes, and cognitive reactions to such changes, may be important for triggering panic attacks. It remains to be determined, however, whether people with panic attacks are actually characterized by enhanced perceptual acuity for interoceptive stimuli. The purpose of this study was to explore the relationship between panic attacks and awareness for cardiac sensations using an objective heartbeat discrimination procedure. Twenty panickers and 20 nonpanickers were given 60 trials of the Whitehead heartbeat discrimination procedure. Thirty trials were given during rest and 30 following hyperventilation. Results indicated that panic attacks were not related to enhanced interoceptive acuity for cardiac sensations, either at rest or following hyperventilation. These results are discussed in terms of their relevance to cognitive models of panic. PMID:8442744

  12. Assessment of Visual Acuity in Relation to Central Nervous System Activation in Children with Mental Retardation.

    ERIC Educational Resources Information Center

    Jacobsen, Karl; Grottland, Havar; Flaten, Magne Arve

    2001-01-01

    Assessment of visual acuity, using Teller Acuity Cards, was combined with observations of behavioral state to indicate central nervous system activation in 24 individuals with mental retardation. Results indicate that forced-choice preferential-looking technique can be used to test visual acuity in this population unless the participant is drowsy.…

  13. A chemically reactive spinning dope for significant improvements in wet spun carbon nanotube fibres.

    PubMed

    González-Domínguez, Jose M; Neri, Wilfrid; Maugey, Maryse; Poulin, Philippe; Ansón-Casaos, Alejandro; Martínez, M Teresa

    2013-05-11

    Single-walled carbon nanotubes can be spun in a polyvinyl alcohol stream to produce nanocomposite fibres. We use a facile ester linking between both elements to create improved fibres which exhibit outstanding enhancements in the absence of post-processing stages, providing a promising alternative based on a chemical method. PMID:23471091

  14. Accommodation, Acuity, and their Relationship to Emmetropization in Infants

    PubMed Central

    Mutti, Donald O.; Mitchell, G. Lynn; Jones, Lisa A.; Friedman, Nina E.; Frane, Sara L.; Lin, Wendy K.; Moeschberger, Melvin L.; Zadnik, Karla

    2009-01-01

    Purpose To evaluate the relationship between accommodation, visual acuity, and emmetropization in human infancy. Methods Defocus at distance and near (57cm) was assessed using Mohindra and dynamic retinoscopy, respectively, in 262 normal birthweight infants at 3, 9, and 18 months of age. Preferential looking provided acuity data at the same ages. The spherical equivalent refractive error was measured by cycloplegic retinoscopy (cyclopentolate 1%). Results Univariate linear regression analyses showed no associations between the change in refractive error and defocus at distance or near. Change in refractive error was linearly related to the accommodative response at distance (R2 = 0.17, p<0.0001) and near (R2 = 0.13, p<0.0001). The ten subjects with the poorest emmetropization relative to the change predicted by the linear effects of their refractive error had higher average levels of hyperopic defocus at distance and near (p-values <0.043). Logistic regression showed a decrease in the odds of reaching +2.00D or less hyperopia by 18 months with increasing levels of hyperopia at 3 months, or if Mohindra retinoscopy was myopic combined with acuity better than the median level of 1.25 logMAR (area under the receiver operating characteristic curve = 0.78 (95% CI = 0.68, 0.88)). Conclusions The level of cycloplegic refractive error was the best single factor for predicting emmetropization by 18 months of age, with smaller contributions from visual acuity and Mohindra retinoscopy. The lack of correlation between defocus and change in refractive error does not support a simple model of emmetropization in response to the level of hyperopic defocus. Infants were capable of maintaining accurate average levels of accommodation across a range of moderate hyperopic refractive errors at 3 months of age. The association between the change in refractive error and accommodative response suggests that the amount of accommodation is a plausible visual signal for emmetropization. PMID

  15. The Two Sides of Sensory-Cognitive Interactions: Effects of Age, Hearing Acuity, and Working Memory Span on Sentence Comprehension.

    PubMed

    DeCaro, Renee; Peelle, Jonathan E; Grossman, Murray; Wingfield, Arthur

    2016-01-01

    Reduced hearing acuity is among the most prevalent of chronic medical conditions among older adults. An experiment is reported in which comprehension of spoken sentences was tested for older adults with good hearing acuity or with a mild-to-moderate hearing loss, and young adults with age-normal hearing. Comprehension was measured by participants' ability to determine the agent of an action in sentences that expressed this relation with a syntactically less complex subject-relative construction or a syntactically more complex object-relative construction. Agency determination was further challenged by inserting a prepositional phrase into sentences between the person performing an action and the action being performed. As a control, prepositional phrases of equivalent length were also inserted into sentences in a non-disruptive position. Effects on sentence comprehension of age, hearing acuity, prepositional phrase placement and sound level of stimulus presentations appeared only for comprehension of sentences with the more syntactically complex object-relative structures. Working memory as tested by reading span scores accounted for a significant amount of the variance in comprehension accuracy. Once working memory capacity and hearing acuity were taken into account, chronological age among the older adults contributed no further variance to comprehension accuracy. Results are discussed in terms of the positive and negative effects of sensory-cognitive interactions in comprehension of spoken sentences and lend support to a framework in which domain-general executive resources, notably verbal working memory, play a role in both linguistic and perceptual processing. PMID:26973557

  16. The Two Sides of Sensory–Cognitive Interactions: Effects of Age, Hearing Acuity, and Working Memory Span on Sentence Comprehension

    PubMed Central

    DeCaro, Renee; Peelle, Jonathan E.; Grossman, Murray; Wingfield, Arthur

    2016-01-01

    Reduced hearing acuity is among the most prevalent of chronic medical conditions among older adults. An experiment is reported in which comprehension of spoken sentences was tested for older adults with good hearing acuity or with a mild-to-moderate hearing loss, and young adults with age-normal hearing. Comprehension was measured by participants’ ability to determine the agent of an action in sentences that expressed this relation with a syntactically less complex subject-relative construction or a syntactically more complex object-relative construction. Agency determination was further challenged by inserting a prepositional phrase into sentences between the person performing an action and the action being performed. As a control, prepositional phrases of equivalent length were also inserted into sentences in a non-disruptive position. Effects on sentence comprehension of age, hearing acuity, prepositional phrase placement and sound level of stimulus presentations appeared only for comprehension of sentences with the more syntactically complex object-relative structures. Working memory as tested by reading span scores accounted for a significant amount of the variance in comprehension accuracy. Once working memory capacity and hearing acuity were taken into account, chronological age among the older adults contributed no further variance to comprehension accuracy. Results are discussed in terms of the positive and negative effects of sensory–cognitive interactions in comprehension of spoken sentences and lend support to a framework in which domain-general executive resources, notably verbal working memory, play a role in both linguistic and perceptual processing. PMID:26973557

  17. Significant improvement in electronic properties of transparent amorphous indium zinc oxide through yttrium doping

    NASA Astrophysics Data System (ADS)

    Sun, Jian; Yu, Zhigen; Huang, Yanhua; Xia, Yijie; Lai, Weng Soon; Gong, Hao

    2014-04-01

    One big challenge in transparent conducting oxides (TCOs) is to achieve high conductivity and mobility at a low processing temperature. Although optimized conductivity has been achieved in indium zinc oxide (IZO) without doping, it is still interesting to find whether doping can improve conductivity of IZO further. In this paper, we report a low processing temperature achievement of high conductivity and mobility of IZO through yttrium (Y) doping. We found that with different Y doping levels, room temperature fabricated amorphous IZO (a-IZO) samples can be controlled to exhibit either metallic or semiconductor characteristics. Y2O3 is demonstrated to be an effective doping source to achieve conductivity 300% higher than the non-doped IZO sample. Anomalously improved mobility of certain Y2O3-doped IZO samples compared with the non-doped IZO sample is found and analyzed. Besides, a low-temperature resistivity anomaly (semiconductor metal transition) phenomenon is observed and discussed.

  18. Brief Communication: Upper air relaxation in RACMO2 significantly improves modelled interannual SMB variability in Antarctica

    NASA Astrophysics Data System (ADS)

    van de Berg, W. J.; Medley, B.

    2015-09-01

    The regional climate model RACMO2 has been a powerful tool for improving SMB estimates from GCMs or reanalyses. However, new yearly SMB observations for West Antarctica show that the modelled interannual variability in SMB is poorly simulated by RACMO2, in contrast to ERA-Interim, which resolves this variability well. In an attempt to remedy RACMO2 performance, we included additional upper air relaxation (UAR) in RACMO2. With UAR, the correlation to observations is similar for RACMO2 and ERA-Interim. The spatial SMB patterns and ice sheet integrated SMB modelled using UAR remain very similar to the estimates of RACMO2 without UAR. We only observe an upstream smoothing of precipitation in regions with very steep topography like the Antarctic Peninsula. We conclude that UAR is a useful improvement for RCM simulations, although results in regions with steep topography should be treated with care.

  19. A comparison of visual acuity, predictability, and visual function outcomes after intracorneal ring segments and laser in situ keratomileusis.

    PubMed Central

    Suiter, B G; Twa, M D; Ruckhofer, J; Schanzlin, D J

    2000-01-01

    PURPOSE: To compare correction of low myopia by intrastromal corneal ring segments (ICRS) and by laser in situ keratomileusis (LASIK) with respect to early visual recovery and refractive outcomes. METHODS: Eighty-two eyes implanted with ICRS in a phase III study for US Food and Drug Administration review were matched with 133 eyes treated with LASIK by criteria of age (> 18 years, < 65 years), preoperative myopia (-1.00 to -3.50 diopters [D]), astigmatism (< or = 1.00 D), single treatment, and attempted full correction. Examinations were performed preoperatively and postoperatively at days 1 and 7 and months 1 and 3. Visual acuity and manifest refraction data were collected retrospectively. Visual function scores were assigned, and summarized results were compared. RESULTS: Uncorrected visual acuity was 20/20 or better at day 1 in 24% of eyes (20/82) after ICRS and in 55% of eyes (73/133) after LASIK, and at month 3 in 75% of eyes (58/77) after ICRS and in 67% of eyes (84/126) after LASIK. Spherical equivalent refraction at month 3 was within +/- 1.00 D of intended correction in 99% of eyes (76/77) after ICRS and in 96% of eyes (121/126) after LASIK. Excellent visual function scores were noted at month 3 in 90% of eyes (69/77) after ICRS and in 78% of eyes (98/126) after LASIK. CONCLUSION: Patients treated with LASIK showed better uncorrected visual acuity immediately following surgery; however, beyond 1 month, patients treated with ICRS achieved better uncorrected visual acuity that continued to improve with time. Visual function scores indicate that ICRS eyes see at higher levels of uncorrected visual acuity than LASIK eyes do with the same refractive error. The ICRS and LASIK were comparable in the correction of mild myopia. PMID:11190040

  20. Significant Advancements in Technology to Improve Instruction for All Students: Including Those with Disabilities

    ERIC Educational Resources Information Center

    Meyen, Edward

    2015-01-01

    Sharing thoughts on what represents significant advancements involving the education of persons for whom typical instruction is not effective seems simple enough. You think about the work you are engaged in and reflect on how you came to do what you are doing. If you have a record of being persistent in your work, then that becomes the context for…

  1. Targeted agri-environment schemes significantly improve the population size of common farmland bumblebee species.

    PubMed

    Wood, Thomas J; Holland, John M; Hughes, William O H; Goulson, Dave

    2015-04-01

    Changes in agricultural practice across Europe and North America have been associated with range contractions and local extinction of bumblebees (Bombus spp.). A number of agri-environment schemes have been implemented to halt and reverse these declines, predominantly revolving around the provision of additional forage plants. Although it has been demonstrated that these schemes can attract substantial numbers of foraging bumblebees, it remains unclear to what extent they actually increase bumblebee populations. We used standardized transect walks and molecular techniques to compare the size of bumblebee populations between Higher Level Stewardship (HLS) farms implementing pollinator-friendly schemes and Entry Level Stewardship (ELS) control farms. Bumblebee abundance on the transect walks was significantly higher on HLS farms than ELS farms. Molecular analysis suggested maximum foraging ranges of 566 m for Bombus hortorum, 714 m for B. lapidarius, 363 m for B. pascuorum and 799 m for B. terrestris. Substantial differences in maximum foraging range were found within bumblebee species between farm types. Accounting for foraging range differences, B. hortorum (47 vs 13 nests/km(2) ) and B. lapidarius (45 vs 22 nests/km(2) ) were found to nest at significantly greater densities on HLS farms than ELS farms. There were no significant differences between farm type for B. terrestris (88 vs 38 nests/km(2) ) and B. pascuorum (32 vs 39 nests/km(2) ). Across all bumblebee species, HLS management had a significantly positive effect on bumblebee nest density. These results show that targeted agri-environment schemes that increase the availability of suitable forage can significantly increase the size of wild bumblebee populations. PMID:25753513

  2. Significant Improvement of Metabolic Characteristics and Bioactivities of Clopidogrel and Analogs by Selective Deuteration.

    PubMed

    Xu, Xueyu; Zhao, Xue; Yang, Zhichao; Wang, Hao; Meng, Xiangjun; Su, Chong; Liu, Mingyuan; Fawcett, John Paul; Yang, Yan; Gu, Jingkai

    2016-01-01

    In the search for prodrug analogs of clopidogrel with improved metabolic characteristics and antiplatelet bioactivity, a group of clopidogrel and vicagrel analogs selectively deuterated at the benzylic methyl ester group were synthesized, characterized, and evaluated. The compounds included clopidogrel-d₃ (8), 2-oxoclopidogrel-d₃ (9), vicagrel-d₃ (10a), and 12 vicagrel-d₃ analogs (10b-10m) with different alkyl groups in the thiophene ester moiety. The D₃C-O bond length in 10a was shown by X-ray single crystal diffraction to be shorter than the H₃C-O bond length in clopidogrel, consistent with the slower rate of hydrolysis of 8 than of clopidogrel in rat whole blood in vitro. A study of the ability of the compounds to inhibit ADP-induced platelet aggregation in fresh rat whole blood collected 2 h after oral dosing of rats with the compounds (7.8 μmol/kg) showed that deuteration increased the activity of clopidogrel and that increasing the size of the alkyl group in the thiophene ester moiety reduced activity. A preliminary pharmacokinetic study comparing 10a with vicagrel administered simultaneously as single oral doses (72 μmol/kg of each drug) to male Wistar rats showed 10a generated more of its active metabolite than vicagrel. These results suggest that 10a is a potentially superior antiplatelet agent with improved metabolic characteristics and bioactivity, and less dose-related toxicity. PMID:27248988

  3. Significant improvement of mouse cloning technique by treatment with trichostatin A after somatic nuclear transfer

    SciTech Connect

    Kishigami, Satoshi . E-mail: kishigami@cdb.riken.jp; Mizutani, Eiji; Ohta, Hiroshi; Hikichi, Takafusa; Thuan, Nguyen Van; Wakayama, Sayaka; Bui, Hong-Thuy; Wakayama, Teruhiko

    2006-02-03

    The low success rate of animal cloning by somatic cell nuclear transfer (SCNT) is believed to be associated with epigenetic errors including abnormal DNA hypermethylation. Recently, we elucidated by using round spermatids that, after nuclear transfer, treatment of zygotes with trichostatin A (TSA), an inhibitor of histone deacetylase, can remarkably reduce abnormal DNA hypermethylation depending on the origins of transferred nuclei and their genomic regions [S. Kishigami, N. Van Thuan, T. Hikichi, H. Ohta, S. Wakayama. E. Mizutani, T. Wakayama, Epigenetic abnormalities of the mouse paternal zygotic genome associated with microinsemination of round spermatids, Dev. Biol. (2005) in press]. Here, we found that 5-50 nM TSA-treatment for 10 h following oocyte activation resulted in more efficient in vitro development of somatic cloned embryos to the blastocyst stage from 2- to 5-fold depending on the donor cells including tail tip cells, spleen cells, neural stem cells, and cumulus cells. This TSA-treatment also led to more than 5-fold increase in success rate of mouse cloning from cumulus cells without obvious abnormality but failed to improve ES cloning success. Further, we succeeded in establishment of nuclear transfer-embryonic stem (NT-ES) cells from TSA-treated cloned blastocyst at a rate three times higher than those from untreated cloned blastocysts. Thus, our data indicate that TSA-treatment after SCNT in mice can dramatically improve the practical application of current cloning techniques.

  4. Near-field visual acuity of pigeons: effects of head location and stimulus luminance.

    PubMed Central

    Hodos, W; Leibowitz, R W; Bonbright, J C

    1976-01-01

    Two pigeons were trained to discriminate a grating stimulus from a blank stimulus of equivalent luminance in a three-key chamber. The stimuli and blanks were presented behind a transparent center key. The procedure was a conditional discrimination in which pecks on the left key were reinforced if the blank had been present behind the center key and pecks on the right key were reinforced if the grating had been present behind the center key. The spatial frequency of the stimuli was varied in each session from four to 29.5 lines per millimeter in accordance with a variation of the method of constant stimuli. The number of lines per millimeter that the subjects could discriminate at threshold was determined from psychometric functions. Data were collected at five values of stimulus luminance ranging from--0.07 to 3.29 log cd/m2. The distance from the stimulus to the anterior nodal point of the eye, which was determined from measurements taken from high-speed motion-picture photographs of three additional pigeons and published intraocular measurements, was 62.0 mm. This distance and the grating detection thresholds were used to calculate the visual acuity of the birds at each level of luminance. Acuity improved with increasing luminance to a peak value of 0.52, which corresponds to a visual angle of 1.92 min, at a luminance of 2.33 log cd/m2. Further increase in luminance produced a small decline in acuity. Images Fig. 1. PMID:932615

  5. Seeing Steps and Ramps with Simulated Low Acuity: Impact of Texture and Locomotion

    PubMed Central

    Bochsler, Tiana M.; Legge, Gordon E.; Kallie, Christopher S.; Gage, Rachel

    2012-01-01

    Purpose Detecting and recognizing steps and ramps is an important component of the visual accessibility of public spaces for people with impaired vision. The present study, which is part of a larger program of research on visual accessibility, investigated the impact of two factors that may facilitate the recognition of steps and ramps during low-acuity viewing. Visual texture on the ground plane is an environmental factor that improves judgments of surface distance and slant. Locomotion (walking) is common during observations of a layout, and may generate visual motion cues that enhance the recognition of steps and ramps. Methods In two experiments, normally sighted subjects viewed the targets monocularly through blur goggles that reduced acuity to either approx. 20/150 Snellen (mild blur) or 20/880 (severe blur). The subjects judged whether a step, ramp or neither was present ahead on a sidewalk. In the texture experiment, subjects viewed steps and ramps on a surface with a coarse black-and-white checkerboard pattern. In the locomotion experiment, subjects walked along the sidewalk toward the target before making judgments. Results Surprisingly, performance was lower with the textured surface than with a uniform surface, perhaps because the texture masked visual cues necessary for target recognition. Subjects performed better in walking trials than in stationary trials, possibly because they were able to take advantage of visual cues that were only present during motion. Conclusions We conclude that under conditions of simulated low acuity, large, high-contrast texture elements can hinder the recognition of steps and ramps while locomotion enhances recognition. PMID:22863792

  6. Significant improvements in the area of stroke timing of motor-operated valves for nuclear plants

    SciTech Connect

    Wohld, P.R. ); Newsome, R.C. )

    1990-01-01

    This paper reports on valve stroke timing test equipment developed and tested for use in a nuclear power plant main control room that can provide significant advantages to the user for valve surveillance testing required by the Nuclear Regulatory Commission. The equipment is particularly suitable for Motor-Operated Valves (MOVs) because of its accuracy and repeatability that is necessary to detect the effects of small changes in actuator motor RPM.

  7. An improved method to set significance thresholds for β diversity testing in microbial community comparisons.

    PubMed

    Gülay, Arda; Smets, Barth F

    2015-09-01

    Exploring the variation in microbial community diversity between locations (β diversity) is a central topic in microbial ecology. Currently, there is no consensus on how to set the significance threshold for β diversity. Here, we describe and quantify the technical components of β diversity, including those associated with the process of subsampling. These components exist for any proposed β diversity measurement procedure. Further, we introduce a strategy to set significance thresholds for β diversity of any group of microbial samples using rarefaction, invoking the notion of a meta-community. The proposed technique was applied to several in silico generated operational taxonomic unit (OTU) libraries and experimental 16S rRNA pyrosequencing libraries. The latter represented microbial communities from different biological rapid sand filters at a full-scale waterworks. We observe that β diversity, after subsampling, is inflated by intra-sample differences; this inflation is avoided in the proposed method. In addition, microbial community evenness (Gini > 0.08) strongly affects all β diversity estimations due to bias associated with rarefaction. Where published methods to test β significance often fail, the proposed meta-community-based estimator is more successful at rejecting insignificant β diversity values. Applying our approach, we reveal the heterogeneous microbial structure of biological rapid sand filters both within and across filters. PMID:25534614

  8. A quantitative analysis of head movement behaviour during visual acuity assessment under prosthetic vision simulation

    NASA Astrophysics Data System (ADS)

    Chen, S. C.; Hallum, L. E.; Suaning, G. J.; Lovell, N. H.

    2007-03-01

    In most current vision prosthesis designs, head movement is the sole director of visual gaze and scanning due to the head-mounted nature of the camera. Study of this unnatural behaviour may provide insight into improved prosthesis designs and rehabilitation procedures. In this paper, we conducted a psychophysical study to investigate the characteristics of head movements of normally sighted subjects undergoing a visual acuity task in simulated prosthetic vision (SPV). In 12 naïve, untrained subjects, we recorded spontaneous changes in the amount of head movements during SPV sessions compared to control (normal vision) sessions. The observed behaviour continued to be refined until five or six sessions of practice. Increased head movement velocity was shown to be correlated to improved visual acuity performance, up to 0.3 logMAR, an equivalent of detecting details at half the physical size compared to complete deprivation of head movements. We postulate that visual scanning can as much as double the spatial frequency information in prosthetic vision. Increased head movement velocity observed when subjects were attempting smaller test items and for low-pass filtering schemes with higher cut-off frequencies may be further evidence that higher frequency content may be available through visual scanning, unconsciously driving subjects to increase head movement velocity.

  9. Upper gastrointestinal bleeding in Scotland 2000-2010: Improved outcomes but a significant weekend effect

    PubMed Central

    Ahmed, Asma; Armstrong, Matthew; Robertson, Ishbel; Morris, Allan John; Blatchford, Oliver; Stanley, Adrian J

    2015-01-01

    AIM: To assess numbers and case fatality of patients with upper gastrointestinal bleeding (UGIB), effects of deprivation and whether weekend presentation affected outcomes. METHODS: Data was obtained from Information Services Division (ISD) Scotland and National Records of Scotland (NRS) death records for a ten year period between 2000-2001 and 2009-2010. We obtained data from the ISD Scottish Morbidity Records (SMR01) database which holds data on inpatient and day-case hospital discharges from non-obstetric and non-psychiatric hospitals in Scotland. The mortality data was obtained from NRS and linked with the ISD SMR01 database to obtain 30-d case fatality. We used 23 ICD-10 (International Classification of diseases) codes which identify UGIB to interrogate database. We analysed these data for trends in number of hospital admissions with UGIB, 30-d mortality over time and assessed effects of social deprivation. We compared weekend and weekday admissions for differences in 30-d mortality and length of hospital stay. We determined comorbidities for each admission to establish if comorbidities contributed to patient outcome. RESULTS: A total of 60643 Scottish residents were admitted with UGIH during January, 2000 and October, 2009. There was no significant change in annual number of admissions over time, but there was a statistically significant reduction in 30-d case fatality from 10.3% to 8.8% (P < 0.001) over these 10 years. Number of admissions with UGIB was higher for the patients from most deprived category (P < 0.05), although case fatality was higher for the patients from the least deprived category (P < 0.05). There was no statistically significant change in this trend between 2000/01-2009/10. Patients admitted with UGIB at weekends had higher 30-d case fatality compared with those admitted on weekdays (P < 0.001). Thirty day mortality remained significantly higher for patients admitted with UGIB at weekends after adjusting for comorbidities. Length of

  10. Lithium deficient mesoporous Li2-xMnSiO4 with significantly improved electrochemical performance

    NASA Astrophysics Data System (ADS)

    Wang, Haiyan; Hou, Tianli; Sun, Dan; Huang, Xiaobing; He, Hanna; Tang, Yougen; Liu, Younian

    2014-02-01

    Li2-xMnSiO4 compounds with mesoporous structure are first proposed in the present work. It is interesting to note that the lithium deficient compounds exhibit much higher electrochemical performance in comparison with the stoichiometric one. Among these compounds, Li1.8MnSiO4 shows the best electrochemical performance. It is found that mesoporous Li1.8MnSiO4 without carbon coating delivers a maximum discharge capacity of 110.9 mAh g-1 at 15 mA g-1, maintaining 90.8 mAh g-1 after 25 cycles, while that of the stoichiometric one is only 48.0 mAh g-1, with 12.5 mAh g-1 remaining. The superior properties are mainly due to the great improvement of electronic conductivity and structure stability, as well as suppressed charge-transfer resistance.

  11. Resolution-adapted recombination of structural features significantly improves sampling in restraint-guided structure calculation

    PubMed Central

    Lange, Oliver F; Baker, David

    2012-01-01

    Recent work has shown that NMR structures can be determined by integrating sparse NMR data with structure prediction methods such as Rosetta. The experimental data serve to guide the search for the lowest energy state towards the deep minimum at the native state which is frequently missed in Rosetta de novo structure calculations. However, as the protein size increases, sampling again becomes limiting; for example, the standard Rosetta protocol involving Monte Carlo fragment insertion starting from an extended chain fails to converge for proteins over 150 amino acids even with guidance from chemical shifts (CS-Rosetta) and other NMR data. The primary limitation of this protocol—that every folding trajectory is completely independent of every other—was recently overcome with the development of a new approach involving resolution-adapted structural recombination (RASREC). Here we describe the RASREC approach in detail and compare it to standard CS-Rosetta. We show that the improved sampling of RASREC is essential in obtaining accurate structures over a benchmark set of 11 proteins in the 15-25 kDa size range using chemical shifts, backbone RDCs and HN-HN NOE data; in a number of cases the improved sampling methodology makes a larger contribution than incorporation of additional experimental data. Experimental data are invaluable for guiding sampling to the vicinity of the global energy minimum, but for larger proteins, the standard Rosetta fold-from-extended-chain protocol does not converge on the native minimum even with experimental data and the more powerful RASREC approach is necessary to converge to accurate solutions. PMID:22423358

  12. A patient/family-centered strategic plan can drive significant improvement.

    PubMed

    Brilli, Richard J; Crandall, Wallace V; Berry, Janet C; Stoverock, Linda; Rosen, Kerry; Budin, Lee; Kelleher, Kelly J; Gleeson, Sean P; Davis, J Terrance

    2014-08-01

    The use of a PFCSP, as a road map to operationalize the hospital's vision, has been a compelling paradigm to achieve significant QI results. The framework is simple yet directly aligns with the IOM domains of quality. It has inspired and helped actively engage hospital personnel in the work required to achieve the goals and vision of the hospital system. Five years after initiating this type of plan, activity is flourishing in each of the domains and midterm results are substantial. We think that the nature of this strategic plan has been an important aspect of our success to date. PMID:25037128

  13. Effect of Myopic Defocus on Visual Acuity after Phakic Intraocular Lens Implantation and Wavefront-guided Laser in Situ Keratomileusis

    PubMed Central

    Kamiya, Kazutaka; Shimizu, Kimiya; Igarashi, Akihito; Kawamorita, Takushi

    2015-01-01

    This study aimed to investigate the effect of myopic defocus on visual acuity after phakic intraocular lens (IOL) implantation and wavefront-guided laser in situ keratomileusis (wfg-LASIK). Our prospective study comprised thirty eyes undergoing posterior chamber phakic IOL implantation and 30 eyes undergoing wfg-LASIK. We randomly measured visual acuity under myopic defocus after cycloplegic and non-cycloplegic correction. We also calculated the modulation transfer function by optical simulation and estimated visual acuity from Campbell & Green’s retinal threshold curve. Visual acuity in the phakic IOL group was significantly better than that in the wfg-LASIK group at myopic defocus levels of 0, –1, and –2 D (p < 0.001, p < 0.001, and p = 0.02, Mann-Whitney U-test), but not at a defocus of –3 D (p = 0.30). Similar results were also obtained in a cycloplegic condition. Decimal visual acuity values at a myopic defocus of 0, −1, −2, and -3 D by optical simulation were estimated to be 1.95, 1.21, 0.97, and 0.75 in the phakic IOL group, and 1.39, 1.11, 0.94, and 0.71 in the wfg-LASIK group, respectively. From clinical and optical viewpoints, phakic IOL implantation was superior to wfg-LASIK in terms of the postoperative visual performance, even in the presence of low to moderate myopic regression. PMID:25994984

  14. Active loading into extracellular vesicles significantly improves the cellular uptake and photodynamic effect of porphyrins.

    PubMed

    Fuhrmann, Gregor; Serio, Andrea; Mazo, Manuel; Nair, Rekha; Stevens, Molly M

    2015-05-10

    Extracellular vesicles (EVs) are phospholipid-based particles endogenously produced by cells. Their natural composition and selective cell interactions make them promising drug carriers. However, in order to harness their properties, efficient exogenous drug encapsulation methods need to be investigated. Here, EVs from various cellular origins (endothelial, cancer and stem cells) were produced and characterised for size and composition. Porphyrins of different hydrophobicities were employed as model drugs and encapsulated into EVs using various passive and active methods (electroporation, saponin, extrusion and dialysis). Hydrophobic compounds loaded very efficiently into EVs and at significantly higher amounts than into standard liposomes composed of phosphocholine and cholesterol using passive incubation. Moreover, loading into EVs significantly increased the cellular uptake by >60% and the photodynamic effect of hydrophobic porphyrins in vitro compared to free or liposome encapsulated drug. The active encapsulation techniques, with the saponin-assisted method in particular, allowed an up to 11 fold higher drug loading of hydrophilic porphyrins compared to passive methods. EVs loaded with hydrophilic porphyrins induced a stronger phototoxic effect than free drug in a cancer cell model. Our findings create a firm basis for the development of EVs as smart drug carriers based on straightforward and transferable methods. PMID:25483424

  15. Possible breakthrough: Significant improvement of signal to noise ratio by stochastic resonance

    SciTech Connect

    Kiss, L.B.

    1996-06-01

    The {ital simplest} {ital stochastic} {ital resonator} {ital is} {ital used}, {ital a} {ital level} {ital crossing} {ital detector} (LCD), to investigate key properties of stochastic resonance (SR). It is pointed out that successful signal processing and biological applications of SR require to work in the {ital large} {ital signal} {ital limit} (nonlinear transfer limit) which requires a completely new approach: {ital wide} {ital band} {ital input} {ital signal} and a {ital new}, {ital generalised} {ital definition} {ital of} {ital output} {ital noise}. The new way of approach is illustrated by a new arrangement. The arrangement employs a special LCD, white input noise and a special, large, subthreshold wide band signal. {ital First} {ital time} {ital in} {ital the} {ital history} {ital of} {ital SR} (for a wide band input noise), the {ital signal} {ital to} {ital noise} {ital ratio} {ital becomes} {ital much} {ital higher} {ital at} {ital the} {ital output} of a stochastic resonator than {ital at} {ital its} {ital input}. In that way, SR is proven to have a potential to improve signal transfer. Note, that the new arrangement seems to have resemblance to {ital neurone} {ital models}, therefore, it has a potential also for biological applications. {copyright} {ital 1996 American Institute of Physics.}

  16. Three-phase textile nanocomposites: significant improvements in strength, toughness and ductility.

    PubMed

    Srivastava, Iti; Proper, Andrew; Rafiee, Mohammad A; Koratkar, Nikhil

    2010-02-01

    It is well established that in-plane tensile properties of unidirectional microfiber-reinforced composites are not significantly influenced by addition of carbon nanotubes to the matrix. This is because the principal effect of the nanotubes is to enhance the matrix dominated (out-of-plane) properties. Here we report that the above situation changes when nanotubes are incorporated into woven-fabric (textile) composites. We report up to 200% increase in strain-to-break and 180% increase in toughness under in-plane tensile load with approximately 0.05% weight of nanotube additives. We attribute this effect to the geometrical arrangement of the micro-fibers and the critical role of the pure-matrix-block in textile composites. PMID:20352752

  17. Are Individual Differences in Reading Speed Related to Extrafoveal Visual Acuity and Crowding?

    PubMed Central

    Frömer, Romy; Dimigen, Olaf; Niefind, Florian; Krause, Niels; Kliegl, Reinhold; Sommer, Werner

    2015-01-01

    Readers differ considerably in their speed of self-paced reading. One factor known to influence fixation durations in reading is the preprocessing of words in parafoveal vision. Here we investigated whether individual differences in reading speed or the amount of information extracted from upcoming words (the preview benefit) can be explained by basic differences in extrafoveal vision—i.e., the ability to recognize peripheral letters with or without the presence of flanking letters. Forty participants were given an adaptive test to determine their eccentricity thresholds for the identification of letters presented either in isolation (extrafoveal acuity) or flanked by other letters (crowded letter recognition). In a separate eye-tracking experiment, the same participants read lists of words from left to right, while the preview of the upcoming words was manipulated with the gaze-contingent moving window technique. Relationships between dependent measures were analyzed on the observational level and with linear mixed models. We obtained highly reliable estimates both for extrafoveal letter identification (acuity and crowding) and measures of reading speed (overall reading speed, size of preview benefit). Reading speed was higher in participants with larger uncrowded windows. However, the strength of this relationship was moderate and it was only observed if other sources of variance in reading speed (e.g., the occurrence of regressive saccades) were eliminated. Moreover, the size of the preview benefit—an important factor in normal reading—was larger in participants with better extrafoveal acuity. Together, these results indicate a significant albeit moderate contribution of extrafoveal vision to individual differences in reading speed. PMID:25789812

  18. Global regulator engineering significantly improved Escherichia coli tolerances toward inhibitors of lignocellulosic hydrolysates.

    PubMed

    Wang, Jianqing; Zhang, Yan; Chen, Yilu; Lin, Min; Lin, Zhanglin

    2012-12-01

    Lignocellulosic biomass is regarded as the most viable source of feedstock for industrial biorefinery, but the harmful inhibitors generated from the indispensable pretreatments prior to fermentation remain a daunting technical hurdle. Using an exogenous regulator, irrE, from the radiation-resistant Deinococcus radiodurans, we previously showed that a novel global regulator engineering (GRE) approach significantly enhanced tolerances of Escherichia coli to alcohol and acetate stresses. In this work, an irrE library was subjected to selection under various stresses of furfural, a typical hydrolysate inhibitor. Three furfural tolerant irrE mutants including F1-37 and F2-1 were successfully obtained. The cells containing these mutants reached OD(600) levels of 4- to 16-fold of that for the pMD18T cells in growth assay under 0.2% (v/v) furfural stress. The cells containing irrE F1-37 and F2-1 also showed considerably reduced intracellular oxygen species (ROS) levels under furfural stress. Moreover, these two irrE mutants were subsequently found to confer significant cross tolerances to two other most common inhibitors, 5-hydroxymethyl-2-furaldehyde (HMF), vanillin, as well as real lignocellulosic hydrolysates. When evaluated in Luria-Bertani (LB) medium supplemented with corn stover cellulosic hydrolysate (prepared with a solid loading of 30%), the cells containing the mutants exhibited lag phases markedly shortened by 24-44 h in comparison with the control cells. This work thus presents a promising step forward to resolve the inhibitor problem for E. coli. From the view of synthetic biology, irrE can be considered as an evolvable "part" for various stresses. Furthermore, this GRE approach can be extended to exploit other exogenous global regulators from extremophiles, and the native counterparts in E. coli, for eliciting industrially useful phenotypes. PMID:22684885

  19. Increased Macular Pigment Optical Density and Visual Acuity following Consumption of a Buttermilk Drink Containing Lutein-Enriched Egg Yolks: A Randomized, Double-Blind, Placebo-Controlled Trial

    PubMed Central

    van der Made, Sanne M.; Kelly, Elton R.; Kijlstra, Aize; Plat, Jogchum

    2016-01-01

    Purpose. To study the effect of 1-year daily consumption of a dairy drink containing lutein-enriched egg yolks on macular pigment optical density (MPOD) and visual function parameters in elderly subjects with ocular drusen and/or retinal pigment abnormalities. Methods. One hundred and one subjects were recruited to participate in this randomized, double-blind, placebo-controlled parallel intervention trial. Statistical analyses were performed with 46 subjects in the lutein group and 43 in the control group. MPOD, best corrected visual acuity (BCVA, logMAR), and dark adaptation were measured at the start of the study, after 6 months and after 12 months. Plasma lutein and zeaxanthin concentrations were assessed at baseline and at the end of the study. Results. In the lutein group, plasma lutein concentrations increased significantly from 205 ng/mL at baseline to 399 ng/mL after twelve months of intervention. MPOD increased significantly from 0.45 to 0.52 and BCVA improved significantly from −0.04 to −0.09 LogMar. Differences in rod dark adaptation rate between both groups were not significant. Conclusion. Daily consumption of a dairy drink containing lutein-enriched egg yolks for one year improves visual acuity, MPOD, and plasma lutein concentration in elderly subjects with drusen and/or retinal pigment epithelial abnormalities. PMID:27064326

  20. Impact of visual acuity on developing literacy at age 4–5 years: a cohort-nested cross-sectional study

    PubMed Central

    Bruce, Alison; Fairley, Lesley; Chambers, Bette; Wright, John; Sheldon, Trevor A

    2016-01-01

    Objectives To estimate the prevalence of poor vision in children aged 4–5 years and determine the impact of visual acuity on literacy. Design Cross-sectional study linking clinical, epidemiological and education data. Setting Schools located in the city of Bradford, UK. Participants Prevalence was determined for 11 186 children participating in the Bradford school vision screening programme. Data linkage was undertaken for 5836 Born in Bradford (BiB) birth cohort study children participating both in the Bradford vision screening programme and the BiB Starting Schools Programme. 2025 children had complete data and were included in the multivariable analyses. Main outcome measures Visual acuity was measured using a logMAR Crowded Test (higher scores=poorer visual acuity). Literacy measured by Woodcock Reading Mastery Tests-Revised (WRMT-R) subtest: letter identification (standardised). Results The mean (SD) presenting visual acuity was 0.14 (0.09) logMAR (range 0.0–1.0). 9% of children had a presenting visual acuity worse than 0.2logMAR (failed vision screening), 4% worse than 0.3logMAR (poor visual acuity) and 2% worse than 0.4logMAR (visually impaired). Unadjusted analysis showed that the literacy score was associated with presenting visual acuity, reducing by 2.4 points for every 1 line (0.10logMAR) reduction in vision (95% CI −3.0 to −1.9). The association of presenting visual acuity with the literacy score remained significant after adjustment for demographic and socioeconomic factors reducing by 1.7 points (95% CI −2.2 to −1.1) for every 1 line reduction in vision. Conclusions Prevalence of decreased visual acuity was high compared with other population-based studies. Decreased visual acuity at school entry is associated with reduced literacy. This may have important implications for the children's future educational, health and social outcomes. PMID:26883240

  1. Oxamflatin Significantly Improves Nuclear Reprogramming, Blastocyst Quality, and In Vitro Development of Bovine SCNT Embryos

    PubMed Central

    Li, Yanyan; Li, Ruizhe; Li, Qian; Wu, Yongyan; Quan, Fusheng; Liu, Jun; Guo, Zekun; Zhang, Yong

    2011-01-01

    Aberrant epigenetic nuclear reprogramming results in low somatic cloning efficiency. Altering epigenetic status by applying histone deacetylase inhibitors (HDACi) enhances developmental potential of somatic cell nuclear transfer (SCNT) embryos. The present study was carried out to examine the effects of Oxamflatin, a novel HDACi, on the nuclear reprogramming and development of bovine SCNT embryos in vitro. We found that Oxamflatin modified the acetylation status on H3K9 and H3K18, increased total and inner cell mass (ICM) cell numbers and the ratio of ICM∶trophectoderm (TE) cells, reduced the rate of apoptosis in SCNT blastocysts, and significantly enhanced the development of bovine SCNT embryos in vitro. Furthermore, Oxamflatin treatment suppressed expression of the pro-apoptotic gene Bax and stimulated expression of the anti-apoptotic gene Bcl-XL and the pluripotency-related genes OCT4 and SOX2 in SCNT blastocysts. Additionally, the treatment also reduced the DNA methylation level of satellite I in SCNT blastocysts. In conclusion, Oxamflatin modifies epigenetic status and gene expression, increases blastocyst quality, and subsequently enhances the nuclear reprogramming and developmental potential of SCNT embryos. PMID:21912607

  2. A Cell Type Independent Binary Grading System Does Not Significantly Improve Endometrial Biopsy Interpretation.

    PubMed

    Nastic, Denis; Kahlin, Frida; Dahlstrand, Hanna; Carlson, Joseph W

    2016-05-01

    The revised International Federation of Gynecology and Obstetrics (FIGO) grading system is widely accepted as the standard in evaluating endometrial carcinoma on biopsy. Determination of tumor cell type [using the World Health Organization (WHO) diagnostic criteria] and grade (using FIGO) guides surgical approach. Several studies have highlighted discrepancies between biopsy and hysterectomy diagnosis. Recently, a binary grading system was proposed, yielding a low-risk and high-risk assessment but in a cell type independent (CTI) way. No study has assessed its utility in biopsy grading, a situation where this system may be particularly useful. Archived endometrial biopsies from 70 cases of endometrial carcinoma were graded by 3 independent observers using the WHO/FIGO and the CTI grading systems. The overall accuracy, interobserver agreement, and ease of use were assessed. This study found comparable substantial accuracy between the WHO/FIGO and CTI grading systems (κ=0.71 vs. κ=0.69), with the same setbacks in overgrading of 20.9% versus 25.6% of low-risk tumors. The CTI grading system was not superior to the WHO/FIGO grading system in accuracy of subtyping and grading and interobserver reproducibility. Although determination of cell type is difficult, it does not appear that the proposed CTI system confers any significant advantages over existing grading. PMID:26863477

  3. Under-reporting of notifiable infectious disease hospitalizations: significant improvements in the Irish context.

    PubMed

    Brabazon, E D; Sheridan, A; Finnegan, P; Carton, M W; Bedford, D

    2015-04-01

    Notification of infectious disease is essential for prompt public health action and epidemiological analysis. The aim of this study was to compare national hospitalization data to national notification data in order to assess if there was significant under-reporting of hospitalized notifiable infectious diseases in recent years in Ireland. All in-patient discharges from public hospitals in the Republic of Ireland from 2006 to 2011 with a principal diagnosis of a notifiable disease were compared with national notification data. It was found that only a potential 1·8% of extra notifications could have arisen due to these hospitalization events and would represent a tenfold reduction on a previous estimate of under-reporting in the Irish context. Viral meningitis, viral encephalitis, bacterial meningitis not otherwise specified and malaria were the most common diseases for which there were more hospitalizations than notifications reported. The results of this study support the conclusion that the reduction in under-reporting can mainly be accounted for by the introduction of laboratories as notifiers in conjunction with the roll out of the Computerized Infectious Disease Reporting system (CIDR). However, for the diseases highlighted, the notification data underestimates the true burden of disease and this has implications for understanding the epidemiology of these diseases. PMID:25035904

  4. Routine Testing for Anaerobic Bacteria in Cerebrospinal Fluid Cultures Improves Recovery of Clinically Significant Pathogens

    PubMed Central

    Pittman, Meredith E.; Thomas, Benjamin S.; Wallace, Meghan A.; Weber, Carol J.

    2014-01-01

    In North America, the widespread use of vaccines targeting Haemophilus influenzae type b and Streptococcus pneumoniae have dramatically altered the epidemiology of bacterial meningitis, while the methodology for culturing cerebrospinal fluid (CSF) specimens has remained largely unchanged. The aims of this study were 2-fold: to document the current epidemiology of bacterial meningitis at a tertiary care medical center and to assess the clinical utility of routinely querying for anaerobes in CSF cultures. To that end, we assessed CSF cultures submitted over a 2-year period. A brucella blood agar (BBA) plate, incubated anaerobically for 5 days, was included in the culture procedure for all CSF specimens during the second year of evaluation. In the pre- and postimplementation years, 2,353 and 2,302 CSF specimens were cultured, with 49 and 99 patients having positive culture results, respectively. The clinical and laboratory data for patients with positive cultures were reviewed. Anaerobic bacteria were isolated in the CSF samples from 33 patients post-BBA compared to two patients pre-BBA (P = 0.01). The anaerobic isolates included Bacteroides thetaiotaomicron (n = 1), Propionibacterium species (n = 15), and Propionibacterium acnes (n = 19) isolates; all of these isolates were recovered on the BBA. Eight of the 35 patients from whom anaerobic organisms were isolated received antimicrobial therapy. Although six of these patients had central nervous system hardware, two patients did not have a history of a neurosurgical procedure and had community-acquired anaerobic bacterial meningitis. This study demonstrates that the simple addition of an anaerobically incubated BBA to the culture of CSF specimens enhances the recovery of clinically significant anaerobic pathogens. PMID:24622102

  5. Occupation-related long-term sensory training enhances roughness discrimination but not tactile acuity.

    PubMed

    Mueller, S; Winkelmann, C; Krause, F; Grunwald, M

    2014-06-01

    Extensive use of sensorimotor properties has been shown to lead to use-dependent plasticity in the human motor cortex as well as sensory areas. The sensory consequences of these cortical changes, however, remain widely unclear. We were interested whether job-related long-term haptic training is measurable in terms of changes in haptic perception (active touch exploration) in manual physiotherapists (PT). To that end, the haptic thresholds of PT (students and employed) and registered osteopathic manual therapists (OMT; PT with postgraduate specialization) were measured and compared to age- and sex-matched control groups. Additionally, tactile acuity (passive static touch) was assessed using grating domes. PT and OMT had superior mean haptic thresholds compared to the control group, suggesting an increase in sensitivity through use. An age-related decline in haptic perception capacity occurred only in the control group, suggesting that the job-related training of the manual therapist groups may have slowed their age-related decline. Contrary to our expectation, we found significantly poorer mean haptic threshold results in the PT student group than for the controls. No significant differences or changes in tactile acuity were found for any of the groups (students and professional). The present results demonstrate use-dependent plasticity in manual therapists. Furthermore, the results underline the known effect of a superior discrimination ability of haptic as opposed to tactile perception. PMID:24609417

  6. Improving Significant Wave Height detection for Coastal Satellite Altimetry: validation in the German Bight.

    NASA Astrophysics Data System (ADS)

    Passaro, Marcello; Benveniste, Jérôme; Cipollini, Paolo; Fenoglio-Marc, Luciana

    For more than two decades, it has been possible to map the Significant Wave Height (SWH) globally through Satellite Altimetry. SWH estimation is possible because the shape of an altimetric waveform, which usually presents a sharp leading edge and a slowly decaying trailing edge, depends on the sea state: in particular, the higher the sea state, the longer the rising time of the leading edge. The algorithm for SWH also depends on the width of the point target response (PTR) function, which is usually approximated by a constant value that contributes to the rising time. Particularly challenging for SWH detection are coastal data and low sea states. The first are usually flagged as unreliable due to land and calm water interference in the altimeter footprint; the second are characterized by an extremely sharp leading edge that is consequently poorly sampled in the digitalized waveform. ALES, a new algorithm for reprocessing altimetric waveforms, has recently been validated for sea surface height estimation (Passaro et al. 2014). The aim of this work is to check its validity also for SWH estimation in a particularly challenging area. The German Bight region presents both low sea state and coastal issues and is particularly suitable for validation, thanks to the extended network of buoys of the Bundesamt für Seeschifffahrt und Hydrographie (BSH). In-situ data include open sea, off-shore and coastal sea conditions, respectively at the Helgoland, lighthouse Alte Weser and Westerland locations. Reprocessed data from Envisat, Jason-1 and Jason-2 tracks are validated against those three buoys. The in-situ validation is applied both at the nearest point and at points along-track. The skill metrics is based on bias, standard deviation, slope of regression line, scatter index, number of cycles with correlation larger than 90%. The same metrics is applied to the altimeter data obtained by standard processing and the validation results are compared. Data are evaluated at high

  7. Temporal perceptual coding using a visual acuity model

    NASA Astrophysics Data System (ADS)

    Adzic, Velibor; Cohen, Robert A.; Vetro, Anthony

    2014-02-01

    This paper describes research and results in which a visual acuity (VA) model of the human visual system (HVS) is used to reduce the bitrate of coded video sequences, by eliminating the need to signal transform coefficients when their corresponding frequencies will not be detected by the HVS. The VA model is integrated into the state of the art HEVC HM codec. Compared to the unmodified codec, up to 45% bitrate savings are achieved while maintaining the same subjective quality of the video sequences. Encoding times are reduced as well.

  8. Development of retinal structure and visual acuity in Japanese flounder ( Paralichthys olivaceus)

    NASA Astrophysics Data System (ADS)

    Zhang, Xiu-Mei; Gao, Tian-Xiang; Arimoto, Takafumi

    2000-12-01

    The retinal structure and visual acuity in Japanese flounder Paralichthys olivaceus at different stages of development were examined by light microscopy. The resolving power of the retina, the visual axis and the best visual field were estimated based on the distribution of cone cells in the retina. The visual system of the larvae appears poorly developed at hatching. The larvae with total length (TL) of less than 10 mm, have single cones only and the eyes were well pigmented. At 10 11 mm TL, most single cones fused to form double cones, with the single and double cones forming a mosaic pattern. From larvae to early juvenile the retina stretches, the cones increase in diameter and rods increase in number. Based on the highest density of the cones in the ventro-temporal region, the visual axis was orientated upforward. The resolving power of the retina in 40 530 mm TL Japanese flounder was found to range from 25.1 to 11.5 min. The results indicated continual improvements in the visual system of the growing fish towards higher resolving power, visual acuity and sensitivity.

  9. Factors affecting visual acuity after one year of follow up after repeated intravitreal ranibizumab for macular degeneration

    PubMed Central

    Williams, Gwyn Samuel; Seow, Eulee; Evans, Huw; Owoniyi, Muyiwa; Evans, Sam; Blyth, Christopher

    2015-01-01

    Aim Providing intravitreal ranibizumab therapy for neovascular age related macular degeneration (nARMD) is a source of increasing strain for many UK eye departments. Whilst most units attempt to adhere to the product licence of following up patients at four weekly intervals; delays in follow up appointments can and do occur. We aim to see if mean follow up intervals during the maintenance phase are correlated with visual outcomes at one year and perform a multivariate analysis of patient factors in a bit to understand the factors affecting visual acuity outcomes. Method A continuously updated prospective audit of patients receiving ranibizumab therapy at the Royal Gwent Hospital was accessed and a coefficient of determination and Spearman’s rank test undertaken to see whether mean follow up delays resulted in visual acuity penalties after nine months of maintenance. Multivariate analysis using ANOVA was then undertaken to examine in more detail the various factors affecting visual acuity outcomes. Results 805 eyes of 708 patients were included in the study. Mean follow up intervals varied between 28.0 and 96.3 days over the first six treatments of the maintenance phase (mean 49.2 – SD 10.7) with a mean change in visual acuity from baseline of +7.1 letters at 12 weeks and +4.6 letters at 52 weeks. There was a negative correlation seen between visual acuity gains after nine months of the maintenance phase and increasing clinic follow up times although Spearman’s rank analysis demonstrated a correlation coefficient of only −0.078, which was not statistically significant. Variability in follow up appointments resulting in worse outcomes was however significant (p < 0.01), as was increasing age at presentation (p = 0.04). Smoking was found to decrease age of presentation by six years (74.2 years vs 80.0 years). The adjusted R2 for the whole analysis was 0.44. Conclusion Wide variation in follow up intervals was associated with a worse visual acuity

  10. Levodopa-carbidopa may improve vision loss in indirect traumatic optic neuropathy.

    PubMed

    Razeghinejad, M Reza; Rahat, Feisal; Bagheri, Mohammadhadi

    2010-10-01

    To compare the effect of levodopa-carbidopa on the visual outcome of patients with indirect traumatic optic neuropathy (ITON), this randomized, double-blind, placebo-controlled study was conducted on 32 patients with ITON within 6 days after trauma. Patients underwent a complete ocular examination, pattern visual evoked potential (PVEP) testing, and high-resolution orbital computed tomography (CT) scanning. All patients received high-dose intravenous methylprednisolone, and levodopa was also administered to the levodopa group. The main outcome measures were best corrected visual acuity and PVEP results at the last-completed examination. The study was completed on 16 patients in the levodopa group and 10 patients in the placebo group because the others were lost to follow-up. There were no statistically significant differences for age, sex, involved eye, ocular and CT scan findings, pretreatment visual acuity, frequency of recordable PVEPs, and follow-up. In the levodopa group the visual acuity improved significantly after treatment (p = 0.009), but not in the placebo group (p = 0.34). After treatment the visual acuity in the levodopa group was 2.1 ± 2.1, and in the placebo group was 3.9 ± 1.2 (p = 0.008). In those who had visual acuity less than or equal to figure count, significant improvement in visual acuity was observed in the levodopa group (p = 0.03), but not in the placebo group (p = 0.34). However, the final visual acuity in these patients was comparable after treatment (p = 0.21). Nine patients (56.2%) in the levodopa group, and 1 (10%) in the placebo group, experienced improvement in visual acuity (p = 0.02). The frequency of unrecordable PVEPs were comparable in both groups (p = 0.09). Patients treated with levodopa within 6 days of onset of ITON were more likely to experience improvement in visual acuity than those in the placebo group. PMID:20649490

  11. Determination of myopes' visual acuity using stimuli with different contrast

    NASA Astrophysics Data System (ADS)

    Ikaunieks, G.; Caure, E.; Kassaliete, E.; Meskovska, Z.

    2012-10-01

    The influence of different contrast stimuli on the myopes’ visual acuity (VA) was studied using positive (35.7), negative (-0.97) and low contrast (-0.11) Landolt optotypes. Test subjects were 13 myopes with corrected eyesight and 8 emmetropes, all of them being 20-22 years old. For VA determination the FrACT computer program was employed. In the tests it was found that for emmetropes the positive and negative contrast VA values do not differ significantly, while for myopes the respective values are better with positive than with negative contrast stimuli. These differences were the same in the measurements taken with spectacles or contact lenses. Our results also show that the retinal straylight created by clean spectacles or soft contact lenses is similar in both cases. Dažu autoru pētījumi rāda, ka miopijas gadījumā redzes asums ir labāks ar pozitīva Vēbera kontrasta stimuliem (balts stimuls uz melna fona) nekā negatīva kontrasta stimuliem (melns stimuls uz balta fona). Šis fenomens tiek saistītas ar neirālām izmaiņām ON un OFF ceļos un miopiskās acīs. Citi pētījumi rāda, ka arī acī izkliedētās gaismas ietekmē labāks redzes asums ir ar pozitīviem kontrasta stimuliem nekā negatīva. Miopijas gadījumā papildus gaismas izkliedi rada briļļu lēcas vai kontaktlēcas. Mēs savā pētījumā vēlējāmies noskaidrot, cik lielā mērā labāks redzes asums ar pozitīva kontrasta stimuliem miopiskās acīs ir saistāms ar optiskās korekcijas radīto gaismas izkliedi. Pētījumā piedalījās 21 dalībnieks - 8 emetropi un 13 miopi ar sfērisko refrakcijas lielumu no -1.25 līdz -6,25 D. Dalībnieku vecums bija no 20 līdz 22 gadi. Izmantojot FrACT datorprogrammu, tika noteiks monokulārais redzes asums VA ar Landolta gredzeniem pie pozitīva, negatīva un zema kontrasta fotopiskos apstākļos. Vēbera kontrasti stimuliem attiecīgi bija 35.7, -0.97 un -0.11. Miopiem mērījumi tika veikti gan ar brillēm, gan

  12. Influences of multiple memory systems on auditory mental image acuity.

    PubMed

    Navarro Cebrian, Ana; Janata, Petr

    2010-05-01

    The influence of different memory systems and associated attentional processes on the acuity of auditory images, formed for the purpose of making intonation judgments, was examined across three experiments using three different task types (cued-attention, imagery, and two-tone discrimination). In experiment 1 the influence of implicit long-term memory for musical scale structure was manipulated by varying the scale degree (leading tone versus tonic) of the probe note about which a judgment had to be made. In experiments 2 and 3 the ability of short-term absolute pitch knowledge to develop was manipulated by presenting blocks of trials in the same key or in seven different keys. The acuity of auditory images depended on all of these manipulations. Within individual listeners, thresholds in the two-tone discrimination and cued-attention conditions were closely related. In many listeners, cued-attention thresholds were similar to thresholds in the imagery condition, and depended on the amount of training individual listeners had in playing a musical instrument. The results indicate that mental images formed at a sensory/cognitive interface for the purpose of making perceptual decisions are highly malleable. PMID:21117767

  13. Significant Improvements to LOGIST.

    ERIC Educational Resources Information Center

    Wingersky, Marilyn S.

    The computer program LOGIST (Wingersky, Patrick, and Lord, 1988) estimates the item parameters and the examinee's abilities for Birnbaum's three-parameter logistic item response theory model using Newton's method for solving the joint maximum likelihood equations. In 1989, Martha Stocking discovered a problem with this procedure in that when the…

  14. Impact on stereo-acuity of two presbyopia correction approaches: monovision and small aperture inlay

    PubMed Central

    Fernández, Enrique J.; Schwarz, Christina; Prieto, Pedro M.; Manzanera, Silvestre; Artal, Pablo

    2013-01-01

    Some of the different currently applied approaches that correct presbyopia may reduce stereovision. In this work, stereo-acuity was measured for two methods: (1) monovision and (2) small aperture inlay in one eye. When performing the experiment, a prototype of a binocular adaptive optics vision analyzer was employed. The system allowed simultaneous measurement and manipulation of the optics in both eyes of a subject. The apparatus incorporated two programmable spatial light modulators: one phase-only device using liquid crystal on silicon technology for wavefront manipulation and one intensity modulator for controlling the exit pupils. The prototype was also equipped with a stimulus generator for creating retinal disparity based on two micro-displays. The three-needle test was programmed for characterizing stereo-acuity. Subjects underwent a two-alternative forced-choice test. The following cases were tested for the stimulus placed at distance: (a) natural vision; (b) 1.5 D monovision; (c) 0.75 D monovision; (d) natural vision and small pupil; (e) 0.75 D monovision and small pupil. In all cases the standard pupil diameter was 4 mm and the small pupil diameter was 1.6 mm. The use of a small aperture significantly reduced the negative impact of monovision on stereopsis. The results of the experiment suggest that combining micro-monovision with a small aperture, which is currently being implemented as a corneal inlay, can yield values of stereoacuity close to those attained under normal binocular vision. PMID:23761846

  15. Smartphone-Based Visual Acuity Measurement for Screening and Clinical Assessment

    PubMed Central

    Brady, Christopher J.; Eghrari, Allen O.; Labrique, Alain B.

    2016-01-01

    IMPORTANCE Visual acuity is the most frequently performed measure of visual function in clinical practice and most people worldwide living with visual impairment are living in low- and middle-income countries. OBJECTIVE To design and validate a smartphone-based visual acuity test that is not dependent on familiarity with symbols or letters commonly used in the English language. DESIGN, SETTING, AND PARTICIPANTS Validation study conducted from December 11, 2013, to March 4, 2014, comparing results from smartphone-based Peek Acuity to Snellen acuity (clinical normal) charts and the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart (reference standard). This study was nested within the 6-year follow-up of the Nakuru Eye Disease Cohort in central Kenya and included 300 adults aged 55 years and older recruited consecutively. MAIN OUTCOMES AND MEASURES Outcome measures were monocular logMAR visual acuity scores for each test: ETDRS chart logMAR, Snellen acuity, and Peek Acuity. Peek Acuity was compared, in terms of test-retest variability and measurement time, with the Snellen acuity and ETDRS logMAR charts in participants’ homes and temporary clinic settings in rural Kenya in 2013 and 2014. RESULTS The 95%CI limits for test-retest variability of smartphone acuity data were ±0.029 logMAR. The mean differences between the smartphone-based test and the ETDRS chart and the smartphone-based test and Snellen acuity data were 0.07 (95%CI, 0.05–0.09) and 0.08 (95%CI, 0.06–0.10) logMAR, respectively, indicating that smartphone-based test acuities agreed well with those of the ETDRS and Snellen charts. The agreement of Peek Acuity and the ETDRS chart was greater than the Snellen chart with the ETDRS chart (95%CI, 0.05–0.10; P = .08). The local Kenyan community health care workers readily accepted the Peek Acuity smartphone test; it required minimal training and took no longer than the Snellen test (77 seconds vs 82 seconds; 95%CI, 71–84 seconds vs 73–91

  16. Natalizumab Significantly Improves Cognitive Impairment over Three Years in MS: Pattern of Disability Progression and Preliminary MRI Findings

    PubMed Central

    Mattioli, Flavia; Stampatori, Chiara; Bellomi, Fabio; Scarpazza, Cristina; Capra, Ruggero

    2015-01-01

    Previous studies reported that Multiple Sclerosis (MS) patients treated with natalizumab for one or two years exhibit a significant reduction in relapse rate and in cognitive impairment, but the long term effects on cognitive performance are unknown. This study aimed to evaluate the effects of natalizumab on cognitive impairment in a cohort of 24 consecutive patients with relapsing remitting MS treated for 3 years. The neuropsychological tests, as well as relapse number and EDSS, were assessed at baseline and yearly for three years. The impact on cortical atrophy was also considered in a subgroup of them, and are thus to be considered as preliminary. Results showed a significant reduction in the number of impaired neuropsychological tests after three years, a significant decrease in annualized relapse rate at each time points compared to baseline and a stable EDSS. In the neuropsychological assessment, a significant improvement in memory, attention and executive function test scores was detected. Preliminary MRI data show that, while GM volume did not change at 3 years, a significantly greater parahippocampal and prefrontal gray matter density was noticed, the former correlating with neuropsychological improvement in a memory test. This study showed that therapy with Natalizumab is helpful in improving cognitive performance, and is likely to have a protective role on grey matter, over a three years follow-up. PMID:26148120

  17. Visual acuity in an opportunistic raptor, the chimango caracara (Milvago chimango).

    PubMed

    Potier, Simon; Bonadonna, Francesco; Kelber, Almut; Duriez, Olivier

    2016-04-01

    Raptors are always considered to have an extraordinary resolving power of their eyes (high visual acuity). Nevertheless, raptors differ in their diet and foraging tactics, which could lead to large differences in visual acuity. The visual acuity of an opportunist bird of prey, the Chimango caracara (Mivalgo chimango) was estimated by operant conditioning. Three birds were trained to discriminate two stimuli, a positive grey uniform pattern and a negative grating pattern stimulus. The visual acuity range from 15.08 to 39.83cycles/degrees. When compared to other birds, they have a higher visual acuity than non-raptorial birds, but they have the lowest visual acuity found in bird of prey so far. We discuss this result in the context of the ecology of the bird, with special focus on it is foraging tactic. PMID:26821187

  18. [Predicting visual acuity in media opacities and uncorrectable refractive errors. Assessing so-called "retinal visual acuity"].

    PubMed

    Lachenmayr, B

    1990-01-01

    Three different components contribute to the modulation transfer function of the visual system: (1) formation of the optical image (refractive media, pupil); (2) scattering of light in the prereceptoral layers of the retina; (3) neuronal processing in the retina und superior visual centers. In the presence of media opacities or non-correctable refractive errors, the clinical question often arises as to which macular function can be expected under the assumption of normal optical image formation (e.g. prior to cataract extraction, corneal transplantation, or vitrectomy). Simple tests such as light projection, color discrimination, and two-point discrimination cannot provide adequate information about macular function. The same holds true for the global luminance ERG. The X-ray phosphene is obsolete. The Maddox rod (with limitations), transilluminated Amsler grid, and various entoptic phenomena (Purkinje vascular phenomenon, foveal chagrin, Haidinger's brushes, blue field phenomenon) are available as qualitative subjective tests. Maxwellian view systems with pinhole aperture (potential acuity meter PAM) and the interferometers (retinometer, visometer, SITE-IRAS interferometer) provide quantitative subjective methods. The flash VECP is primarily a qualitative objective test that allows semiquantitative acuity prediction under special conditions (unilateral opacities). Psychophysical criteria that are less affected by the quality of the retinal image show promising developments in future subjective tests, e.g. optotypes in positive contrast, optotypes or targets superimposed on a background of optical noise, or hyperacuity. Future objective test developments are pattern VECP or even pattern ERG elicited by interferometric stimulation, speckle VECP and focal ERG. PMID:2083891

  19. Impaired acuity of the approximate number system underlies mathematical learning disability (dyscalculia).

    PubMed

    Mazzocco, Michèle M M; Feigenson, Lisa; Halberda, Justin

    2011-01-01

    Many children have significant mathematical learning disabilities (MLD, or dyscalculia) despite adequate schooling. The current study hypothesizes that MLD partly results from a deficiency in the Approximate Number System (ANS) that supports nonverbal numerical representations across species and throughout development. In this study of 71 ninth graders, it is shown that students with MLD have significantly poorer ANS precision than students in all other mathematics achievement groups (low, typically, and high achieving), as measured by psychophysical assessments of ANS acuity (w) and of the mappings between ANS representations and number words (cv). This relation persists even when controlling for domain-general abilities. Furthermore, this ANS precision does not differentiate low-achieving from typically achieving students, suggesting an ANS deficit that is specific to MLD. PMID:21679173

  20. Comparability of ophthalmic diagnoses by clinical and Reading Center examiners in the Visual Acuity Impairment Survey Pilot Study.

    PubMed

    Sperduto, R D; Hiller, R; Podgor, M J; Palmberg, P; Ferris, F L; Wentworth, D

    1986-12-01

    Technologic advances in ophthalmic equipment offer the possibility of replacing direct clinical examinations with Reading Center evaluations of data recorded in epidemiologic studies. Clinical and Reading Center examiners made independent ophthalmic diagnoses of 133 right and 132 left eyes of 138 adults in the Visual Acuity Impairment Survey Pilot Study, carried out in three US cities, Boston, Detroit, and Minneapolis, in August 1981-December 1982. The Reading Center diagnosed eye conditions using only photographic and visual field data collected at the time of the clinical examination. In the comparisons of clinical and Reading Center evaluations reported here, only eyes judged by the examiners to have pathology severe enough to reduce visual acuity to 6/9 or worse were classified as having pathology. (No visual acuity criterion was required for the diagnosis of glaucoma or diabetic retinopathy.) There was agreement in diagnostic assessments between clinical and Reading Center examiners in about 80% of eyes. The kappa statistic, which adjusts for chance agreement, was in the fair to good range: 0.60 for 133 right eyes and 0.62 for 132 left eyes. When the Reading Center examiners were provided with additional information on medical history, refractive error and best corrected visual acuity, the agreement between clinical and Reading Center assessments among the subset of eyes with 6/9 or worse vision again was in the fair to good range, with kappas of 0.61 for 45 right eyes and 0.68 for 48 left eyes. Inter-observer agreement between Reading Center examiners in diagnosing pathology was in the good to excellent range. Use of Reading Centers in future epidemiologic studies should be considered, but elimination of the clinical examinations is not recommended until modifications in the protocol described here have been made and shown to improve levels of agreement between clinical and Reading Center examiners. PMID:3776982

  1. Predicting visual acuity from the structure of visual cortex

    PubMed Central

    Srinivasan, Shyam; Carlo, C. Nikoosh; Stevens, Charles F.

    2015-01-01

    Three decades ago, Rockel et al. proposed that neuronal surface densities (number of neurons under a square millimeter of surface) of primary visual cortices (V1s) in primates is 2.5 times higher than the neuronal density of V1s in nonprimates or many other cortical regions in primates and nonprimates. This claim has remained controversial and much debated. We replicated the study of Rockel et al. with attention to modern stereological precepts and show that indeed primate V1 is 2.5 times denser (number of neurons per square millimeter) than many other cortical regions and nonprimate V1s; we also show that V2 is 1.7 times as dense. As primate V1s are denser, they have more neurons and thus more pinwheels than similar-sized nonprimate V1s, which explains why primates have better visual acuity. PMID:26056277

  2. Recovery of stereo acuity in adults with amblyopia

    PubMed Central

    Astle, Andrew T; McGraw, Paul V; Webb, Ben S

    2011-01-01

    Disruption of visual input to one eye during early development leads to marked functional impairments of vision, commonly referred to as amblyopia. A major consequence of amblyopia is the inability to encode binocular disparity information leading to impaired depth perception or stereo acuity. If amblyopia is treated early in life (before 4 years of age), then recovery of normal stereoscopic function is possible. Treatment is rarely undertaken later in life (adulthood) because declining levels of neural plasticity are thought to limit the effectiveness of standard treatments. Here, the authors show that a learning-based therapy, designed to exploit experience-dependent plastic mechanisms, can be used to recover stereoscopic visual function in adults with amblyopia. These cases challenge the long-held dogma that the critical period for visual development and the window for treating amblyopia are one and the same. PMID:22707543

  3. Collective enhancement of numerical acuity by meritocratic leadership in fish.

    PubMed

    Bisazza, Angelo; Butterworth, Brian; Piffer, Laura; Bahrami, Bahador; Miletto Petrazzini, Maria Elena; Agrillo, Christian

    2014-01-01

    It has been known for more than a century that interacting people can generally achieve more accurate decisions than single individuals. Here we show that interacting guppy fish (Poecilia reticulata) achieve a superior level of numerosity discrimination well beyond the average ability of the isolated individual fish. This enhancement of numerical acuity was observed in dyadic interactions when (Experiment 1) the dyad chose which larger shoal of guppies to join and when (Experiment 2) the dyad chose the higher or the lower numerosity among two decision options after having learned the task individually. Dyadic accuracy and that of the more competent member of each dyad matched closely, supporting the hypothesis that meritocratic leadership arises spontaneously between dyadically interacting fish, rather than the 'many wrongs' principle that has been used to explain group superiority in many species. PMID:24691116

  4. Photovoltaic restoration of sight with high visual acuity

    PubMed Central

    Lorach, Henri; Goetz, Georges; Smith, Richard; Lei, Xin; Mandel, Yossi; Kamins, Theodore; Mathieson, Keith; Huie, Philip; Harris, James; Sher, Alexander; Palanker, Daniel

    2015-01-01

    Patients with retinal degeneration lose sight due to gradual demise of photoreceptors. Electrical stimulation of the surviving retinal neurons provides an alternative route for delivery of visual information. We demonstrate that subretinal arrays with 70 μm photovoltaic pixels provide highly localized stimulation, with electrical and visual receptive fields of comparable sizes in rat retinal ganglion cells. Similarly to normal vision, retinal response to prosthetic stimulation exhibits flicker fusion at high frequencies, adaptation to static images and non-linear spatial summation. In rats with retinal degeneration, these photovoltaic arrays provide spatial resolution of 64 ± 11 μm, corresponding to half of the normal visual acuity in pigmented rats. Ease of implantation of these wireless and modular arrays, combined with their high resolution opens the door to functional restoration of sight. PMID:25915832

  5. Sensitivity of The Dynamic Visual Acuity Test To Sensorimotor Change

    NASA Technical Reports Server (NTRS)

    Cohen, Helen; Bloomberg, Jacob; Elizalde, Elizabeth; Fregia, Melody

    1999-01-01

    Post-flight astronauts, acutely post-vestibular nerve section patients, and patients with severe chronic bilateral vestibular deficits have oscillopsia caused by reduced vestibulocular reflex gains and decreased postural stability. Therefore, as previous work has shown, a test of dynamic visual acuity (DVA), in which the subject must read numbers from a computer screen while standing still or walking in place provides a composite measure of sensorimotor integration. This measure may be useful for determining the level of recovery, post-flight, post-operatively, or after vestibular rehabilitation. To determine the sensitivity of DVA to change in impaired populations we have tested patients with acoustic neuromas before and during the first post-operative week after resection of the tumors, and with bilaterally labyrinthine deficient subjects before and after six weeks of balance rehabilitation therapy.

  6. Comparison of the performance of the CRUSADE, ACUITY-HORIZONS, and ACTION bleeding risk scores in STEMI undergoing primary PCI: insights from a cohort of 1391 patients

    PubMed Central

    Couto-Mallón, D; Rodríguez-Garrido, J; García-Guimaraes, M; Gargallo-Fernández, P; Piñón-Esteban, P; Aldama-López, G; Salgado-Fernández, J; Calviño-Santos, R; Vázquez-González, N; Castro-Beiras, A

    2013-01-01

    Aims: To compare the performance of the CRUSADE, ACUITY-HORIZONS, and ACTION risk models in the ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). Methods: We studied all consecutive patients with STEMI who underwent PPCI at our institution between 2006 and 2010 (n=1391). The CRUSADE, ACUITY-HORIZONS, and ACTION risk scores were calculated based on the patients’ clinical characteristics. The occurrence of in-hospital major bleeding (defined as the composite of intracranial or intraocular bleeding, access site haemorrhage requiring intervention, reduction in haemoglobin ≥4 g/dl without or ≥3g/dl with overt bleeding source, reoperation for bleeding, or blood transfusion) reached 9.8%. Calibration and discrimination of the three risk models were evaluated by the Hosmer−Lemeshow test and the C-statistic, respectively. We compared the predictive accuracy of the risk scores by the DeLong non-parametric test. Results: Calibration of the three risk scores was adequate, given the non-significant results of Hosmer−Lemeshow test for the three risk models. Discrimination of CRUSADE, ACUITY-HORIZONS, and ACTION models was good (C-statistic 0.77, 0.70, and 0.78, respectively). The CRUSADE and ACTION risk scores had a greater predictive accuracy than the ACUITY-HORIZONS risk model (z=3.89, p-value=0.0001 and z=3.51, p-value=0.0004, respectively). There was no significant difference between the CRUSADE and ACTION models (z=0.63, p=0.531). Conclusions: The CRUSADE, ACUITY-HORIZONS, and ACTION scores are useful tools for the risk stratification of bleeding in STEMI treated by PPCI. Our findings favour the CRUSADE and ACTION risk models over the ACUITY-HORIZONS risk score. PMID:24062930

  7. Two-Point Orientation Discrimination Versus the Traditional Two-Point Test for Tactile Spatial Acuity Assessment

    PubMed Central

    Tong, Jonathan; Mao, Oliver; Goldreich, Daniel

    2013-01-01

    Two-point discrimination is widely used to measure tactile spatial acuity. The validity of the two-point threshold as a spatial acuity measure rests on the assumption that two points can be distinguished from one only when the two points are sufficiently separated to evoke spatially distinguishable foci of neural activity. However, some previous research has challenged this view, suggesting instead that two-point task performance benefits from an unintended non-spatial cue, allowing spuriously good performance at small tip separations. We compared the traditional two-point task to an equally convenient alternative task in which participants attempt to discern the orientation (vertical or horizontal) of two points of contact. We used precision digital readout calipers to administer two-interval forced-choice versions of both tasks to 24 neurologically healthy adults, on the fingertip, finger base, palm, and forearm. We used Bayesian adaptive testing to estimate the participants’ psychometric functions on the two tasks. Traditional two-point performance remained significantly above chance levels even at zero point separation. In contrast, two-point orientation discrimination approached chance as point separation approached zero, as expected for a valid measure of tactile spatial acuity. Traditional two-point performance was so inflated at small point separations that 75%-correct thresholds could be determined on all tested sites for fewer than half of participants. The 95%-correct thresholds on the two tasks were similar, and correlated with receptive field spacing. In keeping with previous critiques, we conclude that the traditional two-point task provides an unintended non-spatial cue, resulting in spuriously good performance at small spatial separations. Unlike two-point discrimination, two-point orientation discrimination rigorously measures tactile spatial acuity. We recommend the use of two-point orientation discrimination for neurological assessment. PMID

  8. Measuring acuity of the approximate number system reliably and validly: the evaluation of an adaptive test procedure

    PubMed Central

    Lindskog, Marcus; Winman, Anders; Juslin, Peter; Poom, Leo

    2013-01-01

    Two studies investigated the reliability and predictive validity of commonly used measures and models of Approximate Number System acuity (ANS). Study 1 investigated reliability by both an empirical approach and a simulation of maximum obtainable reliability under ideal conditions. Results showed that common measures of the Weber fraction (w) are reliable only when using a substantial number of trials, even under ideal conditions. Study 2 compared different purported measures of ANS acuity as for convergent and predictive validity in a within-subjects design and evaluated an adaptive test using the ZEST algorithm. Results showed that the adaptive measure can reduce the number of trials needed to reach acceptable reliability. Only direct tests with non-symbolic numerosity discriminations of stimuli presented simultaneously were related to arithmetic fluency. This correlation remained when controlling for general cognitive ability and perceptual speed. Further, the purported indirect measure of ANS acuity in terms of the Numeric Distance Effect (NDE) was not reliable and showed no sign of predictive validity. The non-symbolic NDE for reaction time was significantly related to direct w estimates in a direction contrary to the expected. Easier stimuli were found to be more reliable, but only harder (7:8 ratio) stimuli contributed to predictive validity. PMID:23964256

  9. The role of ANS acuity and numeracy for the calibration and the coherence of subjective probability judgments

    PubMed Central

    Winman, Anders; Juslin, Peter; Lindskog, Marcus; Nilsson, Håkan; Kerimi, Neda

    2014-01-01

    The purpose of the study was to investigate how numeracy and acuity of the approximate number system (ANS) relate to the calibration and coherence of probability judgments. Based on the literature on number cognition, a first hypothesis was that those with lower numeracy would maintain a less linear use of the probability scale, contributing to overconfidence and nonlinear calibration curves. A second hypothesis was that also poorer acuity of the ANS would be associated with overconfidence and non-linearity. A third hypothesis, in line with dual-systems theory (e.g., Kahneman and Frederick, 2002) was that people higher in numeracy should have better access to the normative probability rules, allowing them to decrease the rate of conjunction fallacies. Data from 213 participants sampled from the Swedish population showed that: (i) in line with the first hypothesis, overconfidence and the linearity of the calibration curves were related to numeracy, where people higher in numeracy were well calibrated with zero overconfidence. (ii) ANS was not associated with overconfidence and non-linearity, disconfirming the second hypothesis. (iii) The rate of conjunction fallacies was slightly, but to a statistically significant degree decreased by numeracy, but still high at all numeracy levels. An unexpected finding was that participants with better ANS acuity gave more realistic estimates of their performance relative to others. PMID:25140163

  10. Relationship between Functional Visual Acuity and Useful Field of View in Elderly Drivers

    PubMed Central

    Negishi, Kazuno; Masui, Sachiko; Mimura, Masaru; Fujita, Yoshio; Tsubota, Kazuo

    2016-01-01

    Purpose To investigate the relationship between the functional visual acuity (FVA) and useful field of view (UFOV) in elderly drivers and assess the usefulness of the FVA test to screen driving aptitude in elderly drivers. Methods This study included 45 elderly drivers (31 men, 14 women; mean age, 68.1 years) and 30 younger drivers (26 men, 4 women; mean age, 34.2 years) who drive regularly. All participants underwent measurement of the binocular corrected distant visual acuity (CDVA), binocular corrected distant FVA (CDFVA), and Visual Field with Inhibitory Tasks Elderly Version (VFIT-EV) to measure UFOV. The tear function and cognitive status also were evaluated. Results The CDVA, the CDFVA, cognitive status, and the correct response rate (CAR) of the VFIT-EV were significantly worse in the elderly group than in the control group (P = 0.000 for all parameters). The cognitive status was correlated significantly with the CDVA (r = -0.301, P = 0.009), CDFVA (r = -0.402, P = 0.000), and the CAR of the VFIT-EV (r = 0.348, P = 0.002) in all subjects. The results of the tear function tests were not correlated with the CDVA, CDFVA, or VFIT-EV in any subjects. Stepwise regression analysis for all subjects in the elderly and control groups showed that the CDFVA predicted the CAR most significantly among the clinical factors evaluated. Conclusion The FVA test is a promising method to screen the driving aptitude, including both visual and cognitive functions, in a short time. PMID:26808364

  11. Absolute Pitch—Functional Evidence of Speech-Relevant Auditory Acuity

    PubMed Central

    Oechslin, Mathias S.; Meyer, Martin

    2010-01-01

    Absolute pitch (AP) has been shown to be associated with morphological changes and neurophysiological adaptations in the planum temporale, a cortical area involved in higher-order auditory and speech perception processes. The direct link between speech processing and AP has hitherto not been addressed. We provide first evidence that AP compared with relative pitch (RP) ability is associated with significantly different hemodynamic responses to complex speech sounds. By systematically varying the lexical and/or prosodic information of speech stimuli, we demonstrated consistent activation differences in AP musicians compared with RP musicians and nonmusicians. These differences relate to stronger activations in the posterior part of the middle temporal gyrus and weaker activations in the anterior mid-part of the superior temporal gyrus. Furthermore, this pattern is considerably modulated by the auditory acuity of AP. Our results suggest that the neural underpinnings of pitch processing expertise exercise a strong influence on propositional speech perception (sentence meaning). PMID:19592570

  12. Vernier Acuity and the Magnocellular System Revisited: Response to Skottun and Skoyles

    ERIC Educational Resources Information Center

    Keri, Szabolcs; Benedek, Gyorgy

    2010-01-01

    Skottun and Skoyles (2009) recently presented a comment on Vernier acuity and magnocellular dysfunctions in fragile X premutation carriers (Keri & Benedek, 2009). The authors concluded that our finding that the magnocellular deficit, as revealed by luminance-contrast sensitivity measurements, is associated with impaired Vernier acuity for…

  13. Comparison of Dynamic Visual Acuity between Water Polo Players and Sedentary Students

    ERIC Educational Resources Information Center

    Quevedo-Junyent, Lluisa; Aznar-Casanova, Jose Antonio; Merindano-Encina, Dolores; Cardona, Genis; Sole-Forto, Joan

    2011-01-01

    In this study, we examined differences in dynamic visual acuity between elite and subelite water polo players and sedentary students. To measure dynamic visual acuity binocularly, we asked participants to indicate the orientation of a broken ring, similar to the Landolt C, which increased in size as it moved across a computer screen. Two different…

  14. 49 CFR 240.207 - Procedures for making the determination on vision and hearing acuity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Procedures for making the determination on vision and hearing acuity. 240.207 Section 240.207 Transportation Other Regulations Relating to... making the determination on vision and hearing acuity. (a) Each railroad, prior to initially...

  15. 49 CFR 240.121 - Criteria for vision and hearing acuity data.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Criteria for vision and hearing acuity data. 240... ENGINEERS Component Elements of the Certification Process § 240.121 Criteria for vision and hearing acuity... paragraph (e) of this section, a person's vision and hearing shall meet or exceed the standards...

  16. 49 CFR 240.121 - Criteria for vision and hearing acuity data.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Criteria for vision and hearing acuity data. 240... ENGINEERS Component Elements of the Certification Process § 240.121 Criteria for vision and hearing acuity... paragraph (e) of this section, a person's vision and hearing shall meet or exceed the standards...

  17. 49 CFR 240.207 - Procedures for making the determination on vision and hearing acuity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Procedures for making the determination on vision and hearing acuity. 240.207 Section 240.207 Transportation Other Regulations Relating to... making the determination on vision and hearing acuity. (a) Each railroad, prior to initially...

  18. 49 CFR 240.207 - Procedures for making the determination on vision and hearing acuity.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Procedures for making the determination on vision and hearing acuity. 240.207 Section 240.207 Transportation Other Regulations Relating to... making the determination on vision and hearing acuity. (a) Each railroad, prior to initially...

  19. 49 CFR 240.121 - Criteria for vision and hearing acuity data.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Criteria for vision and hearing acuity data. 240... ENGINEERS Component Elements of the Certification Process § 240.121 Criteria for vision and hearing acuity... paragraph (e) of this section, a person's vision and hearing shall meet or exceed the standards...

  20. 49 CFR 240.121 - Criteria for vision and hearing acuity data.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Criteria for vision and hearing acuity data. 240... ENGINEERS Component Elements of the Certification Process § 240.121 Criteria for vision and hearing acuity... paragraph (e) of this section, a person's vision and hearing shall meet or exceed the standards...

  1. 49 CFR 240.207 - Procedures for making the determination on vision and hearing acuity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Procedures for making the determination on vision and hearing acuity. 240.207 Section 240.207 Transportation Other Regulations Relating to... making the determination on vision and hearing acuity. (a) Each railroad, prior to initially...

  2. 49 CFR 240.207 - Procedures for making the determination on vision and hearing acuity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Procedures for making the determination on vision and hearing acuity. 240.207 Section 240.207 Transportation Other Regulations Relating to... making the determination on vision and hearing acuity. (a) Each railroad, prior to initially...

  3. 49 CFR 240.121 - Criteria for vision and hearing acuity data.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Criteria for vision and hearing acuity data. 240... ENGINEERS Component Elements of the Certification Process § 240.121 Criteria for vision and hearing acuity... paragraph (e) of this section, a person's vision and hearing shall meet or exceed the standards...

  4. Comparison of visual acuity of the patients on the first day after sub-Bowman keratomileusis or laser in situ keratomileusis

    PubMed Central

    Zhao, Wei; Wu, Ting; Dong, Ze-Hong; Feng, Jie; Ren, Yu-Feng; Wang, Yu-Sheng

    2016-01-01

    AIM To compare recovery of the visual acuity in patients one day after sub-Bowman keratomileusis (SBK) or laser in situ keratomileusis (LASIK). METHODS Data from 5923 eyes in 2968 patients that received LASIK (2755 eyes) or SBK (3168 eyes) were retrospectively analyzed. The eyes were divided into 4 groups according to preoperative spherical equivalent: between -12.00 to -9.00 D, extremely high myopia (n=396, including 192 and 204 in SBK and LASIK groups, respectively); -9.00 to -6.00 D, high myopia (n=1822, including 991 and 831 in SBK and LASIK groups, respectively), -6.00 to -3.00 D, moderate myopia (n=3071, including 1658 and 1413 in SBK and LASIK groups, respectively), and -3.00 to 0.00 D, low myopia (n=634, including 327 and 307 in SBK and LASIK groups, respectively). Uncorrected logMAR visual acuity values of patients were assessed under standard natural light. Analysis of variance was used for comparisons among different groups. RESULTS Uncorrected visual acuity values were 0.0115±0.1051 and 0.0466±0.1477 at day 1 after operation for patients receiving SBK and LASIK, respectively (P<0.01); visual acuity values of 0.1854±0.1842, 0.0615±0.1326, -0.0033±0.0978, and -0.0164±0.0972 were obtained for patients in the extremely high, high, moderate, and low myopia groups, respectively (P<0.01). In addition, significant differences in visual acuity at day 1 after operation were found between patients receiving SBK and LASIK in each myopia subgroup. CONCLUSION Compared with LASIK, SBK is safer and more effective, with faster recovery. Therefore, SBK is more likely to be accepted by patients than LASIK for better uncorrected visual acuity the day following operation. PMID:27158619

  5. Significant improvement of GaN crystal quality with ex-situ sputtered AlN nucleation layers

    NASA Astrophysics Data System (ADS)

    Chen, Shuo-Wei; Yang, Young; Wen, Wei-Chih; Li, Heng; Lu, Tien-Chang

    2016-03-01

    Ex-situ sputtered AlN nucleation layer has been demonstrated effective to significantly improve crystal quality and electrical properties of GaN epitaxy layers for GaN based Light-emitting diodes (LEDs). In this report, we have successfully reduced X-ray (102) FWHM from 240 to 110 arcsec, and (002) FWHM from 230 to 101 arcsec. In addition, reverse-bias voltage (Vr) increased around 20% with the sputtered AlN nucleation layer. Furthermore, output power of LEDs grown on sputtered AlN nucleation layer can be improved around 4.0% compared with LEDs which is with conventional GaN nucleation layer on pattern sapphire substrate (PSS).

  6. The Use of Dynamic Visual Acuity as a Functional Test of Gaze Stabilization Following Space Flight

    NASA Technical Reports Server (NTRS)

    Peters, B. T.; Mulavara, A. P.; Brady, R.; Miller, C. A.; Richards, J. T.; Warren, L. E.; Cohen, H. S.; Bloomberg, J. J.

    2006-01-01

    After prolonged exposure to a given gravitational environment the transition to another is accompanied by adaptations in the sensorimotor subsystems, including the vestibular system. Variation in the adaptation time course of these subsystems, and the functional redundancies that exist between them make it difficult to accurately assess the functional capacity and physical limitations of astro/cosmonauts using tests on individual subsystems. While isolated tests of subsystem performance may be the only means to address where interventions are required, direct measures of performance may be more suitable for assessing the operational consequences of incomplete adaptation to changes in the gravitational environment. A test of dynamic visual acuity (DVA) is currently being used in the JSC Neurosciences Laboratory as part of a series of measures to assess the efficacy of a countermeasure to mitigate postflight locomotor dysfunction. In the current protocol, subjects visual acuity is determined using Landolt ring optotypes presented sequentially on a computer display. Visual acuity assessments are made both while standing and while walking at 1.8 m/s on a motorized treadmill. The use of a psychophysical threshold detection algorithm reduces the required number of optotype presentations and the results can be presented immediately after the test. The difference between the walking and standing acuity measures provides a metric of the change in the subject s ability to maintain gaze fixation on the visual target while walking. This functional consequence is observable regardless of the underlying subsystem most responsible for the change. Data from 15 cosmo/astronauts have been collected following long-duration (approx. 6 months) stays in space using a visual target viewing distance of 4.0 meters. An investigation of the group mean shows a change in DVA soon after the flight that asymptotes back to baseline approximately one week following their return to earth. The

  7. Long-term treatment with naproxcinod significantly improves skeletal and cardiac disease phenotype in the mdx mouse model of dystrophy.

    PubMed

    Uaesoontrachoon, Kitipong; Quinn, James L; Tatem, Kathleen S; Van Der Meulen, Jack H; Yu, Qing; Phadke, Aditi; Miller, Brittany K; Gordish-Dressman, Heather; Ongini, Ennio; Miglietta, Daniela; Nagaraju, Kanneboyina

    2014-06-15

    In Duchenne muscular dystrophy (DMD) patients and the mouse model of DMD, mdx, dystrophin deficiency causes a decrease and mislocalization of muscle-specific neuronal nitric oxide synthase (nNOSμ), leading to functional impairments. Previous studies have shown that nitric oxide (NO) donation associated with anti-inflammatory action has beneficial effects in dystrophic mouse models. In this study, we have systematically investigated the effects of naproxcinod, an NO-donating naproxen derivative, on the skeletal and cardiac disease phenotype in mdx mice. Four-week-old mdx and C57BL/10 mice were treated with four different concentrations (0, 10, 21 and 41 mg/kg) of naproxcinod and 0.9 mg/kg of prednisolone in their food for 9 months. All mice were subjected to twice-weekly treadmill sessions, and functional and behavioral parameters were measured at 3, 6 and 9 months of treatment. In addition, we evaluated in vitro force contraction, optical imaging of inflammation, echocardiography and blood pressure (BP) at the 9-month endpoint prior to sacrifice. We found that naproxcinod treatment at 21 mg/kg resulted in significant improvement in hindlimb grip strength and a 30% decrease in inflammation in the fore- and hindlimbs of mdx mice. Furthermore, we found significant improvement in heart function, as evidenced by improved fraction shortening, ejection fraction and systolic BP. In addition, the long-term detrimental effects of prednisolone typically seen in mdx skeletal and heart function were not observed at the effective dose of naproxcinod. In conclusion, our results indicate that naproxcinod has significant potential as a safe therapeutic option for the treatment of muscular dystrophies. PMID:24463621

  8. Long-term treatment with naproxcinod significantly improves skeletal and cardiac disease phenotype in the mdx mouse model of dystrophy

    PubMed Central

    Uaesoontrachoon, Kitipong; Quinn, James L; Tatem, Kathleen S; Van Der Meulen, Jack H; Yu, Qing; Phadke, Aditi; Miller, Brittany K; Gordish-Dressman, Heather; Ongini, Ennio; Miglietta, Daniela; Nagaraju, Kanneboyina

    2014-01-01

    In Duchenne muscular dystrophy (DMD) patients and the mouse model of DMD, mdx, dystrophin deficiency causes a decrease and mislocalization of muscle-specific neuronal nitric oxide synthase (nNOSμ), leading to functional impairments. Previous studies have shown that nitric oxide (NO) donation associated with anti-inflammatory action has beneficial effects in dystrophic mouse models. In this study, we have systematically investigated the effects of naproxcinod, an NO-donating naproxen derivative, on the skeletal and cardiac disease phenotype in mdx mice. Four-week-old mdx and C57BL/10 mice were treated with four different concentrations (0, 10, 21 and 41 mg/kg) of naproxcinod and 0.9 mg/kg of prednisolone in their food for 9 months. All mice were subjected to twice-weekly treadmill sessions, and functional and behavioral parameters were measured at 3, 6 and 9 months of treatment. In addition, we evaluated in vitro force contraction, optical imaging of inflammation, echocardiography and blood pressure (BP) at the 9-month endpoint prior to sacrifice. We found that naproxcinod treatment at 21 mg/kg resulted in significant improvement in hindlimb grip strength and a 30% decrease in inflammation in the fore- and hindlimbs of mdx mice. Furthermore, we found significant improvement in heart function, as evidenced by improved fraction shortening, ejection fraction and systolic BP. In addition, the long-term detrimental effects of prednisolone typically seen in mdx skeletal and heart function were not observed at the effective dose of naproxcinod. In conclusion, our results indicate that naproxcinod has significant potential as a safe therapeutic option for the treatment of muscular dystrophies. PMID:24463621

  9. Slanted joint axes of the stick insect antenna: an adaptation to tactile acuity

    NASA Astrophysics Data System (ADS)

    Mujagic, Samir; Krause, André F.; Dürr, Volker

    2007-04-01

    Like many flightless, obligatory walking insects, the stick insect Carausius morosus makes intensive use of active antennal movements for tactile near range exploration and orientation. The antennal joints of C. morosus have a peculiar oblique and non-orthogonal joint axis arrangement. Moreover, this arrangement is known to differ from that in crickets (Ensifera), locusts (Caelifera) and cockroaches (Blattodea), all of which have an orthogonal joint axis arrangement. Our hypothesis was that the situation found in C. morosus represents an important evolutionary trait of the order of stick and leaf insects (Phasmatodea). If this was true, it should be common to other species of the Phasmatodea. The objective of this comparative study was to resolve this question. We have measured the joint axis orientation of the head scape and scape pedicel joints along with other parameters that affect the tactile efficiency of the antenna. The obtained result was a complete kinematic description of the antenna. This was used to determine the size and location of kinematic out-of-reach zones, which are indicators of tactile acuity. We show that the oblique and non-orthogonal arrangement is common to eight species from six sub-families indicating that it is a synapomorphic character of the Euphasmatodea. This character can improve tactile acuity compared to the situation in crickets, locusts and cockroaches. Finally, because molecular data of a recent study indicate that the Phasmatodea may have evolved as flightless, obligatory walkers, we argue that the antennal joint axis arrangement of the Euphasmatodea reflects an evolutionary adaptation to tactile near range exploration during terrestrial locomotion.

  10. APD125, a Selective Serotonin 5-HT2A Receptor Inverse Agonist, Significantly Improves Sleep Maintenance in Primary Insomnia

    PubMed Central

    Rosenberg, Russell; Seiden, David J.; Hull, Steven G.; Erman, Milton; Schwartz, Howard; Anderson, Christen; Prosser, Warren; Shanahan, William; Sanchez, Matilde; Chuang, Emil; Roth, Thomas

    2008-01-01

    Introduction: Insomnia is a condition affecting 10% to 15% of the adult population and is characterized by difficulty falling asleep, difficulty staying asleep, or nonrestorative sleep, accompanied by daytime impairment or distress. This study evaluates APD125, a selective inverse agonist of the 5-HT2A receptor, for treatment of chronic insomnia, with particular emphasis on sleep maintenance. In phase 1 studies, APD125 improved sleep maintenance and was well tolerated. Methodology: Adult subjects (n = 173) with DSM-IV defined primary insomnia were randomized into a multicenter, double-blind, placebo-controlled, 3-way crossover study to compare 2 doses of APD125 (10 mg and 40 mg) with placebo. Each treatment period was 7 days with a 7- to 9-day washout period between treatments. Polysomnographic recordings were performed at the initial 2 screening nights and at nights (N) 1/2 and N 6/7 of each treatment period. Results: APD125 was associated with significant improvements in key sleep maintenance parameters measured by PSG. Wake time after sleep onset decreased (SEM) by 52.5 (3.2) min (10 mg) and 53.5 (3.5) min (40 mg) from baseline to N 1/2 vs. 37.8 (3.4) min for placebo, (P < 0.0001 for both doses vs placebo), and by 51.7 (3.4) min (P = 0.01) and 48.0 (3.6) min (P = 0.2) at N 6/7 vs. 44.0 (3.8) min for placebo. Significant APD125 effects on wake time during sleep were also seen (P < 0.0001 N 1/2, P < 0.001 N 6/7). The number of arousals and number of awakenings decreased significantly with APD125 treatment compared to placebo. Slow wave sleep showed a statistically significant dose-dependent increase. There was no significant decrease in latency to persistent sleep. No serious adverse events were reported, and no meaningful differences in adverse event profiles were observed between either dose of APD125 and placebo. APD125 was not associated with next-day psychomotor impairment as measured by Digit Span, Digit Symbol Copy, and Digit Symbol Coding Tests

  11. Significant improvements in InGaN/GaN nano-photoelectrodes for hydrogen generation by structure and polarization optimization.

    PubMed

    Tao, Tao; Zhi, Ting; Liu, Bin; Li, Mingxue; Zhuang, Zhe; Dai, Jiangping; Li, Yi; Jiang, Fulong; Luo, Wenjun; Xie, Zili; Chen, Dunjun; Chen, Peng; Li, Zhaosheng; Zou, Zhigang; Zhang, Rong; Zheng, Youdou

    2016-01-01

    The photoelectrodes based on III-nitride semiconductors with high energy conversion efficiency especially for those self-driven ones are greatly desirable for hydrogen generation. In this study, highly ordered InGaN/GaN multiple-quantum-well nanorod-based photoelectrodes have been fabricated by a soft UV-curing nano-imprint lithography and a top-down etching technique, which improve the incident photon conversion efficiency (IPCE) from 16% (planar structure) to 42% (@ wavelength = 400 nm). More significantly, the turn-on voltage is reduced low to -0.6 V, which indicates the possibility of achieving self-driven. Furthermore, SiO2/Si3N4 dielectric distributed Bragg reflectors are employed to further improve the IPCE up to 60%. And the photocurrent (@ 1.1 V) is enhanced from 0.37 mA/cm(2) (original planar structure) to 1.5 mA/cm(2). These improvements may accelerate the possible applications for hydrogen generation with high energy-efficiency. PMID:26853933

  12. Significant improvements in InGaN/GaN nano-photoelectrodes for hydrogen generation by structure and polarization optimization

    NASA Astrophysics Data System (ADS)

    Tao, Tao; Zhi, Ting; Liu, Bin; Li, Mingxue; Zhuang, Zhe; Dai, Jiangping; Li, Yi; Jiang, Fulong; Luo, Wenjun; Xie, Zili; Chen, Dunjun; Chen, Peng; Li, Zhaosheng; Zou, Zhigang; Zhang, Rong; Zheng, Youdou

    2016-02-01

    The photoelectrodes based on III-nitride semiconductors with high energy conversion efficiency especially for those self-driven ones are greatly desirable for hydrogen generation. In this study, highly ordered InGaN/GaN multiple-quantum-well nanorod-based photoelectrodes have been fabricated by a soft UV-curing nano-imprint lithography and a top-down etching technique, which improve the incident photon conversion efficiency (IPCE) from 16% (planar structure) to 42% (@ wavelength = 400 nm). More significantly, the turn-on voltage is reduced low to -0.6 V, which indicates the possibility of achieving self-driven. Furthermore, SiO2/Si3N4 dielectric distributed Bragg reflectors are employed to further improve the IPCE up to 60%. And the photocurrent (@ 1.1 V) is enhanced from 0.37 mA/cm2 (original planar structure) to 1.5 mA/cm2. These improvements may accelerate the possible applications for hydrogen generation with high energy-efficiency.

  13. Significant improvements in InGaN/GaN nano-photoelectrodes for hydrogen generation by structure and polarization optimization

    PubMed Central

    Tao, Tao; Zhi, Ting; Liu, Bin; Li, Mingxue; Zhuang, Zhe; Dai, Jiangping; Li, Yi; Jiang, Fulong; Luo, Wenjun; Xie, Zili; Chen, Dunjun; Chen, Peng; Li, Zhaosheng; Zou, Zhigang; Zhang, Rong; Zheng, Youdou

    2016-01-01

    The photoelectrodes based on III-nitride semiconductors with high energy conversion efficiency especially for those self-driven ones are greatly desirable for hydrogen generation. In this study, highly ordered InGaN/GaN multiple-quantum-well nanorod-based photoelectrodes have been fabricated by a soft UV-curing nano-imprint lithography and a top-down etching technique, which improve the incident photon conversion efficiency (IPCE) from 16% (planar structure) to 42% (@ wavelength = 400 nm). More significantly, the turn-on voltage is reduced low to −0.6 V, which indicates the possibility of achieving self-driven. Furthermore, SiO2/Si3N4 dielectric distributed Bragg reflectors are employed to further improve the IPCE up to 60%. And the photocurrent (@ 1.1 V) is enhanced from 0.37 mA/cm2 (original planar structure) to 1.5 mA/cm2. These improvements may accelerate the possible applications for hydrogen generation with high energy-efficiency. PMID:26853933

  14. Methylphenidate significantly improves driving performance of adults with attention-deficit hyperactivity disorder: a randomized crossover trial.

    PubMed

    Verster, Joris C; Bekker, Evelijne M; de Roos, Marlise; Minova, Anita; Eijken, Erik J E; Kooij, J J Sandra; Buitelaar, Jan K; Kenemans, J Leon; Verbaten, Marinus N; Olivier, Berend; Volkerts, Edmund R

    2008-05-01

    Although patients with attention-deficit hyperactivity disorder (ADHD) have reported improved driving performance on methylphenidate, limited evidence exists to support an effect of treatment on driving performance and some regions prohibit driving on methylphenidate. A randomized, crossover trial examining the effects of methylphenidate versus placebo on highway driving in 18 adults with ADHD was carried out. After three days of no treatment, patients received either their usual methylphenidate dose (mean: 14.7 mg; range: 10-30 mg) or placebo and then the opposite treatment after a six to seven days washout period. Patients performed a 100 km driving test during normal traffic, 1.5 h after treatment administration. Standard deviation of lateral position (SDLP), the weaving of the car, was the primary outcome measure. Secondary outcome measurements included the standard deviation of speed and patient reports of driving performance. Driving performance was significantly better in the methylphenidate than in the placebo condition, as reflected by the SDLP difference (2.3 cm, 95% CI = 0.8-3.8, P = 0.004). Variation in speed was similar on treatment and on placebo (-0.05 km/h, 95% CI = -0.4 to 0.2, P = 0.70). Among adults with ADHD, with a history of a positive clinical response to methylphenidate, methylphenidate significantly improves driving performance. PMID:18308788

  15. Annonaceous acetogenins (ACGs) nanosuspensions based on a self-assembly stabilizer and the significantly improved anti-tumor efficacy.

    PubMed

    Hong, Jingyi; Li, Yanhong; Xiao, Yao; Li, Yijing; Guo, Yifei; Kuang, Haixue; Wang, Xiangtao

    2016-09-01

    Annonaceous acetogenins (ACGs) have exhibited antitumor activity against various cancers. However, these substances' poor solubility has limited clinical applications. In this study, hydroxypropyl-beta-cyclodextrin (HP-β-CD) and soybean lecithin (SPC) were self-assembled into an amphiphilic complex. ACGs nanosuspensions (ACGs-NSps) were prepared with a mean particle size of 144.4nm, a zeta potential of -22.9mV and a high drug payload of 46.17% using this complex as stabilizer. The ACGs-NSps demonstrated sustained release in vitro and good stability in plasma as well as simulated gastrointestinal fluid, and met the demand of both intravenous injection and oral administration. The ACGs-NSps demonstrated significantly increased cytotoxicity against Hela and HepG2 cancer cell lines compared to ACGs in solution (in vitro cytotoxicity assay). An in vivo study with H22-tumor bearing mice demonstrated that nanosuspensions significantly improved ACGs' antitumor activity. When orally administered, ACGs-NSps achieved a similar tumor inhibition rate at 1/10th the dose of ACGs in an oil solution (47.94% vs. 49.74%, p>0.05). Improved therapeutic efficacy was further achieved when the ACGs-NSps were intravenously injected into mice (70.31%). With the help of nanosuspension technology, ACGs may be an effective antitumor drug for clinic use. PMID:27209384

  16. Improving Growth and Productivity of Oleiferous Brassicas under Changing Environment: Significance of Nitrogen and Sulphur Nutrition, and Underlying Mechanisms

    PubMed Central

    Anjum, Naser A.; Gill, Sarvajeet S.; Umar, Shahid; Ahmad, Iqbal; Duarte, Armando C.; Pereira, Eduarda

    2012-01-01

    Mineral nutrients are the integral part of the agricultural systems. Among important plant nutrients, nitrogen (N) and sulphur (S) are known essential elements for growth, development, and various physiological functions in plants. Oleiferous brassicas (rapeseed and mustard) require higher amounts of S in addition to N for optimum growth and yield. Therefore, balancing S-N fertilization, optimization of nutrient replenishment, minimization of nutrient losses to the environment, and the concept of coordination in action between S and N could be a significant strategy for improvement of growth and productivity of oleiferous brassicas. Additionally, positive interaction between S and N has been reported to be beneficial for various aspects of oilseed brassicas. The current paper updates readers on the significance of N and S for the improvement of plant growth, development, and productivity in detail. In addition, S-N nutrition-mediated control of major plant antioxidant defense system components involved in the removal and/or metabolism of stress-induced/generated reactive oxygen species in plants (hence, the control of plant growth, development, and productivity) has been overviewed. PMID:22629181

  17. Pain sensitivity and tactile spatial acuity are altered in healthy musicians as in chronic pain patients

    PubMed Central

    Zamorano, Anna M.; Riquelme, Inmaculada; Kleber, Boris; Altenmüller, Eckart; Hatem, Samar M.; Montoya, Pedro

    2015-01-01

    Extensive training of repetitive and highly skilled movements, as it occurs in professional classical musicians, may lead to changes in tactile sensitivity and corresponding cortical reorganization of somatosensory cortices. It is also known that professional musicians frequently experience musculoskeletal pain and pain-related symptoms during their careers. The present study aimed at understanding the complex interaction between chronic pain and music training with respect to somatosensory processing. For this purpose, tactile thresholds (mechanical detection, grating orientation, two-point discrimination) and subjective ratings to thermal and pressure pain stimuli were assessed in 17 professional musicians with chronic pain, 30 pain-free musicians, 20 non-musicians with chronic pain, and 18 pain-free non-musicians. We found that pain-free musicians displayed greater touch sensitivity (i.e., lower mechanical detection thresholds), lower tactile spatial acuity (i.e., higher grating orientation thresholds) and increased pain sensitivity to pressure and heat compared to pain-free non-musicians. Moreover, we also found that musicians and non-musicians with chronic pain presented lower tactile spatial acuity and increased pain sensitivity to pressure and heat compared to pain-free non-musicians. The significant increment of pain sensitivity together with decreased spatial discrimination in pain-free musicians and the similarity of results found in chronic pain patients, suggests that the extensive training of repetitive and highly skilled movements in classical musicians could be considered as a risk factor for developing chronic pain, probably due to use-dependent plastic changes elicited in somatosensory pathways. PMID:25610384

  18. Malingering or simulation in ophthalmology-visual acuity.

    PubMed

    Incesu, Ali Ihsan; Sobacı, Güngör

    2011-01-01

    Simulation can be defined as malingering, or sometimes functional visual loss (FVL). It manifests as either simulating an ophthalmic disease (positive simulation), or denial of ophthalmic disease (negative simulation). Conscious behavior and compensation or indemnity claims are prominent features of simulation. Since some authors suggest that this is a manifestation of underlying psychopathology, even conversion is included in this context. In today's world, every ophthalmologist can face with simulation of ophthalmic disease or disorder. In case of simulation suspect, the physician's responsibility is to prove the simulation considering the disease/disorder first, and simulation as an exclusion. In simulation examinations, the physician should be firm and smart to select appropriate test(s) to convince not only the subject, but also the judge in case of indemnity or compensation trials. Almost all ophthalmic sensory and motor functions including visual acuity, visual field, color vision and night vision can be the subject of simulation. Examiner must be skillful in selecting the most appropriate test. Apart from those in the literature, we included all kinds of simulation in ophthalmology. In addition, simulation examination techniques, such as, use of OCT (optical coherence tomography), frequency doubling perimetry (FDP), and modified polarization tests were also included. In this review, we made a thorough literature search, and added our experiences to give the readers up-to-date information on malingering or simulation in ophthalmology. PMID:22553721

  19. From innervation density to tactile acuity: 1. Spatial representation.

    PubMed

    Brown, Paul B; Koerber, H Richard; Millecchia, Ronald

    2004-06-11

    We tested the hypothesis that the population receptive field representation (a superposition of the excitatory receptive field areas of cells responding to a tactile stimulus) provides spatial information sufficient to mediate one measure of static tactile acuity. In psychophysical tests, two-point discrimination thresholds on the hindlimbs of adult cats varied as a function of stimulus location and orientation, as they do in humans. A statistical model of the excitatory low threshold mechanoreceptive fields of spinocervical, postsynaptic dorsal column and spinothalamic tract neurons was used to simulate the population receptive field representations in this neural population of the one- and two-point stimuli used in the psychophysical experiments. The simulated and observed thresholds were highly correlated. Simulated and observed thresholds' relations to physiological and anatomical variables such as stimulus location and orientation, receptive field size and shape, map scale, and innervation density were strikingly similar. Simulated and observed threshold variations with receptive field size and map scale obeyed simple relationships predicted by the signal detection model, and were statistically indistinguishable from each other. The population receptive field representation therefore contains information sufficient for this discrimination. PMID:15140641

  20. Objective evaluation of the visual acuity in human eyes

    NASA Astrophysics Data System (ADS)

    Rosales, M. A.; López-Olazagasti, E.; Ramírez-Zavaleta, G.; Varillas, G.; Tepichín, E.

    2009-08-01

    Traditionally, the quality of the human vision is evaluated by a subjective test in which the examiner asks the patient to read a series of characters of different sizes, located at a certain distance of the patient. Typically, we need to ensure a subtended angle of vision of 5 minutes, which implies an object of 8.8 mm high located at 6 meters (normal or 20/20 visual acuity). These characters constitute what is known as the Snellen chart, universally used to evaluate the spatial resolution of the human eyes. The mentioned process of identification of characters is carried out by means of the eye - brain system, giving an evaluation of the subjective visual performance. In this work we consider the eye as an isolated image-forming system, and show that it is possible to isolate the function of the eye from that of the brain in this process. By knowing the impulse response of the eye´s system we can obtain, in advance, the image of the Snellen chart simultaneously. From this information, we obtain the objective performance of the eye as the optical system under test. This type of results might help to detect anomalous situations of the human vision, like the so called "cerebral myopia".

  1. Acoustic basis of directional acuity in laboratory mice.

    PubMed

    Lauer, Amanda M; Slee, Sean J; May, Bradford J

    2011-10-01

    The acoustic basis of auditory spatial acuity was investigated in CBA/129 mice by relating patterns of behavioral errors to directional features of the head-related transfer function (HRTF). Behavioral performance was assessed by training the mice to lick a water spout during sound presentations from a "safe" location and to suppress the response during presentations from "warning" locations. Minimum audible angles (MAAs) were determined by delivering the safe and warning sounds from different locations in the inter-aural horizontal and median vertical planes. HRTFs were measured at the same locations by implanting a miniature microphone and recording the gain of sound energy near the ear drum relative to free field. Mice produced an average MAA of 31° when sound sources were located in the horizontal plane. Acoustic measures indicated that binaural inter-aural level differences (ILDs) and monaural spectral features of the HRTF change systematically with horizontal location and therefore may have contributed to the accuracy of behavioral performance. Subsequent manipulations of the auditory stimuli and the directional properties of the ear produced errors that suggest the mice primarily relied on ILD cues when discriminating changes in azimuth. The MAA increased beyond 80° when the importance of ILD cues was minimized by testing in the median vertical plane. Although acoustic measures demonstrated a less robust effect of vertical location on spectral features of the HRTF, this poor performance provides further evidence for the insensitivity to spectral cues that was noted during behavioral testing in the horizontal plane. PMID:21717290

  2. Malingering or simulation in ophthalmology-visual acuity

    PubMed Central

    Incesu, Ali Ihsan; Sobacı, Güngör

    2011-01-01

    Simulation can be defined as malingering, or sometimes functional visual loss (FVL). It manifests as either simulating an ophthalmic disease (positive simulation), or denial of ophthalmic disease (negative simulation). Conscious behavior and compensation or indemnity claims are prominent features of simulation. Since some authors suggest that this is a manifestation of underlying psychopathology, even conversion is included in this context. In today's world, every ophthalmologist can face with simulation of ophthalmic disease or disorder. In case of simulation suspect, the physician's responsibility is to prove the simulation considering the disease/disorder first, and simulation as an exclusion. In simulation examinations, the physician should be firm and smart to select appropriate test(s) to convince not only the subject, but also the judge in case of indemnity or compensation trials. Almost all ophthalmic sensory and motor functions including visual acuity, visual field, color vision and night vision can be the subject of simulation. Examiner must be skillful in selecting the most appropriate test. Apart from those in the literature, we included all kinds of simulation in ophthalmology. In addition, simulation examination techniques, such as, use of OCT (optical coherence tomography), frequency doubling perimetry (FDP), and modified polarization tests were also included. In this review, we made a thorough literature search, and added our experiences to give the readers up-to-date information on malingering or simulation in ophthalmology. PMID:22553721

  3. Cognitive aging and hearing acuity: modeling spoken language comprehension

    PubMed Central

    Wingfield, Arthur; Amichetti, Nicole M.; Lash, Amanda

    2015-01-01

    The comprehension of spoken language has been characterized by a number of “local” theories that have focused on specific aspects of the task: models of word recognition, models of selective attention, accounts of thematic role assignment at the sentence level, and so forth. The ease of language understanding (ELU) model (Rönnberg et al., 2013) stands as one of the few attempts to offer a fully encompassing framework for language understanding. In this paper we discuss interactions between perceptual, linguistic, and cognitive factors in spoken language understanding. Central to our presentation is an examination of aspects of the ELU model that apply especially to spoken language comprehension in adult aging, where speed of processing, working memory capacity, and hearing acuity are often compromised. We discuss, in relation to the ELU model, conceptions of working memory and its capacity limitations, the use of linguistic context to aid in speech recognition and the importance of inhibitory control, and language comprehension at the sentence level. Throughout this paper we offer a constructive look at the ELU model; where it is strong and where there are gaps to be filled. PMID:26124724

  4. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis.

    PubMed

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-19

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants. PMID:27160795

  5. Preserved Visual Acuity in Anterior Ischemic Optic Neuropathy Secondary to Giant Cell (temporal) Arteritis

    PubMed Central

    Antonio-Santos, Aileen A.; Murad-Kejbou, Sally J.; Foroozan, Rod; Yedavally, Sunita; Kaufman, David I.; Eggenberger, Eric R.

    2016-01-01

    OBJECTIVE To evaluate the prevalence and clinical profile of patients with biopsy-proven arteritic anterior ischemic optic neuropathy presenting with preserved visual acuity of 20/40 or better and those with an initial poor visual acuity of 20/50 or worse through a retrospective chart review RESULTS Nine of 37 patients with arteritic anterior ischemic optic neuropathy presented with a preserved visual acuity of 20/40 or better in the affected eye. All patients with preserved visual acuity had initial visual field defects that spared the central field. All 37 patients immediately received high-dose corticosteroid therapy. Visual acuity worsened by > 2 lines in one of nine patients (11%) with preserved visual acuity, with a corresponding progression of visual field constriction. CONCLUSION Although preserved visual acuity of 20/40 or better has traditionally been associated with the nonarteritic form of anterior ischemic optic neuropathy, giant cell arteritis should still be strongly considered, especially if they have giant cell arteritis systemic symptoms. PMID:26958148

  6. Significant Improvement of Thermal Stability for CeZrPrNd Oxides Simply by Supercritical CO2 Drying

    PubMed Central

    Fan, Yunzhao; Wang, Zizi; Xin, Ying; Li, Qian; Zhang, Zhaoliang; Wang, Yingxia

    2014-01-01

    Pr and Nd co-doped Ce-Zr oxide solid solutions (CZPN) were prepared using co-precipitation and microemulsion methods. It is found that only using supercritical CO2 drying can result in a significant improvement of specific surface area and oxygen storage capacity at lower temperatures for CZPN after aging at 1000°C for 12 h in comparison with those using conventional air drying and even supercritical ethanol drying. Furthermore, the cubic structure was obtained in spite of the fact that the atomic ratio of Ce/(Ce+Zr+Pr+Nd) is as low as 29%. The high thermal stability can be attributed to the loosely aggregated morphology and the resultant Ce enrichment on the nanoparticle surface, which are caused by supercritical CO2 drying due to the elimination of surface tension effects on the gas-liquid interface. PMID:24516618

  7. Significant improvement of thermal stability for CeZrPrNd oxides simply by supercritical CO(2) drying.

    PubMed

    Fan, Yunzhao; Wang, Zizi; Xin, Ying; Li, Qian; Zhang, Zhaoliang; Wang, Yingxia

    2014-01-01

    Pr and Nd co-doped Ce-Zr oxide solid solutions (CZPN) were prepared using co-precipitation and microemulsion methods. It is found that only using supercritical CO(2) drying can result in a significant improvement of specific surface area and oxygen storage capacity at lower temperatures for CZPN after aging at 1000°C for 12 h in comparison with those using conventional air drying and even supercritical ethanol drying. Furthermore, the cubic structure was obtained in spite of the fact that the atomic ratio of Ce/(Ce+Zr+Pr+Nd) is as low as 29%. The high thermal stability can be attributed to the loosely aggregated morphology and the resultant Ce enrichment on the nanoparticle surface, which are caused by supercritical CO(2) drying due to the elimination of surface tension effects on the gas-liquid interface. PMID:24516618

  8. Does levodopa improve vision in albinism? Results of a randomized, controlled clinical trial

    PubMed Central

    Summers, C Gail; Connett, John E; Holleschau, Ann M; Anderson, Jennifer L; De Becker, Inge; McKay, Brian S; Brilliant, Murray H

    2014-01-01

    Background Dopamine is an intermediate product in the biosynthesis of melanin pigment, which is absent or reduced in albinism. Animal research has shown that supplying a precursor to dopamine, levodopa, may improve visual acuity in albinism by enhancing neural networks. This study examines the safety and effectiveness of levodopa on best-corrected visual acuity in human subjects with albinism. Design Prospective, randomized, placebo-controlled, double-masked randomized clinical trial conducted at the University of Minnesota Participants 45 subjects with albinism Methods Subjects with albinism were randomly assigned to one of three treatment arms: levodopa 0.76 mg/kg with 25% carbidopa, levodopa 0.51 mg/kg with 25% carbidopa, or placebo and followed for 20 weeks, with best-corrected visual acuity measured at enrollment, and at weeks 5, 10, 15, and 20 after enrollment. Side effects were recorded with a symptom survey. Blood was drawn for genotyping. Main Outcome Measures Side effects and best-corrected visual acuity 20 weeks after enrollment. Results All subjects had at least one mutation found in a gene known to cause albinism. Mean age was 14.5 years (range: 3.5 to 57.8 years). Follow-up was 100% and compliance was good. Minor side effects were reported; there were no serious adverse events. There was no statistically significant improvement in best-corrected visual acuity after 20 weeks with either dose of levodopa. Conclusions Levodopa, in the doses used in this trial and for the time course of administration, did not improve visual acuity in subjects with albinism. PMID:24641678

  9. Codon Optimization Significantly Improves the Expression Level of α -Amylase Gene from Bacillus licheniformis in Pichia pastoris.

    PubMed

    Wang, Jian-Rong; Li, Yang-Yuan; Liu, Dan-Ni; Liu, Jing-Shan; Li, Peng; Chen, Li-Zhi; Xu, Shu-De

    2015-01-01

    α-Amylase as an important industrial enzyme has been widely used in starch processing, detergent, and paper industries. To improve expression efficiency of recombinant α-amylase from Bacillus licheniformis (B. licheniformis), the α-amylase gene from B. licheniformis was optimized according to the codon usage of Pichia pastoris (P. pastoris) and expressed in P. pastoris. Totally, the codons encoding 305 amino acids were optimized in which a total of 328 nucleotides were changed and the G+C content was increased from 47.6 to 49.2%. The recombinants were cultured in 96-deep-well microplates and screened by a new plate assay method. Compared with the wild-type gene, the optimized gene is expressed at a significantly higher level in P. pastoris after methanol induction for 168 h in 5- and 50-L bioreactor with the maximum activity of 8100 and 11000 U/mL, which was 2.31- and 2.62-fold higher than that by wild-type gene. The improved expression level makes the enzyme a good candidate for α-amylase production in industrial use. PMID:26171389

  10. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    PubMed Central

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-01-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system. PMID:25652244

  11. The crystallization of apo-form UMP kinase from Xanthomonas campestris is significantly improved in a strong magnetic field

    SciTech Connect

    Tu, Jhe-Le; Chin, Ko-Hsin; Wang, Andrew H.-J.; Chou, Shan-Ho

    2007-05-01

    A bacterial UMP kinase from the plant pathogen X. campestris pathovar campestris has been overexpressed in E. coli, purified and crystallized in a strong magnetic field. The crystals diffracted to 2.35 Å. Bacterial UMP kinases (UMPKs) are crucial enzymes that are responsible for microbial UTP biosynthesis. Interestingly, eukaryotic and prokaryotic cells use different enzymes for UMP-phosphorylation reactions. Prokaryotic UMPKs are thus believed to be potential targets for antimicrobial drug development. Here, the cloning, expression and crystallization of SeMet-substituted XC1936, a bacterial UMPK from Xanthomonas campestris pathovar campestris, are reported. The crystallization of the apo-form UMPK was found to be significantly improved in a strong magnetic field; the crystals diffracted to a resolution of 2.35 Å, a dramatic improvement over the original value of 3.6 Å. Preliminary structural analyses of apo-form XC1936 using crystals grown in a strong magnetic field clearly reveal well defined loop regions involved in substrate-analogue binding that were previously not visible. Crystallization in a strong magnetic field thus was found to be indispensable in determining the flexible region of the XC1936 UMPK structure.

  12. Zero Valent Iron Significantly Enhances Methane Production from Waste Activated Sludge by Improving Biochemical Methane Potential Rather Than Hydrolysis Rate

    NASA Astrophysics Data System (ADS)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-01

    Anaerobic digestion has been widely applied for waste activated sludge (WAS) treatment. However, methane production from anaerobic digestion of WAS is usually limited by the slow hydrolysis rate and/or poor biochemical methane potential of WAS. This work systematically studied the effects of three different types of zero valent iron (i.e., iron powder, clean scrap and rusty scrap) on methane production from WAS in anaerobic digestion, by using both experimental and mathematical approaches. The results demonstrated that both the clean and the rusty iron scrap were more effective than the iron powder for improving methane production from WAS. Model-based analysis showed that ZVI addition significantly enhanced methane production from WAS through improving the biochemical methane potential of WAS rather than its hydrolysis rate. Economic analysis indicated that the ZVI-based technology for enhancing methane production from WAS is economically attractive, particularly considering that iron scrap can be freely acquired from industrial waste. Based on these results, the ZVI-based anaerobic digestion process of this work could be easily integrated with the conventional chemical phosphorus removal process in wastewater treatment plant to form a cost-effective and environment-friendly approach, enabling maximum resource recovery/reuse while achieving enhanced methane production in wastewater treatment system.

  13. Codon Optimization Significantly Improves the Expression Level of α-Amylase Gene from Bacillus licheniformis in Pichia pastoris

    PubMed Central

    Wang, Jian-Rong; Li, Yang-Yuan; Liu, Dan-Ni; Liu, Jing-Shan; Li, Peng; Chen, Li-Zhi; Xu, Shu-De

    2015-01-01

    α-Amylase as an important industrial enzyme has been widely used in starch processing, detergent, and paper industries. To improve expression efficiency of recombinant α-amylase from Bacillus licheniformis (B. licheniformis), the α-amylase gene from B. licheniformis was optimized according to the codon usage of Pichia pastoris (P. pastoris) and expressed in P. pastoris. Totally, the codons encoding 305 amino acids were optimized in which a total of 328 nucleotides were changed and the G+C content was increased from 47.6 to 49.2%. The recombinants were cultured in 96-deep-well microplates and screened by a new plate assay method. Compared with the wild-type gene, the optimized gene is expressed at a significantly higher level in P. pastoris after methanol induction for 168 h in 5- and 50-L bioreactor with the maximum activity of 8100 and 11000 U/mL, which was 2.31- and 2.62-fold higher than that by wild-type gene. The improved expression level makes the enzyme a good candidate for α-amylase production in industrial use. PMID:26171389

  14. Higher-order aberrations and best-corrected visual acuity in Native American children with a high prevalence of astigmatism

    PubMed Central

    Miller, Joseph M.; Harvey, Erin M.; Schwiegerling, Jim

    2016-01-01

    Purpose To determine whether higher-order aberrations (HOAs) in children from a highly astigmatic population differ from population norms and whether HOAs are associated with astigmatism and reduced best-corrected visual acuity. Methods Subjects were 218 Tohono O’odham Native American children 5–9 years of age. Noncycloplegic HOA measurements were obtained with a handheld Shack-Hartmann sensor (SHS). Signed (z06s to z14s) and unsigned (z06u to z14u) wavefront aberration Zernike coefficients Z(3,−3) to Z(4,4) were rescaled for a 4 mm diameter pupil and compared to adult population norms. Cycloplegic refraction and best-corrected logMAR letter visual acuity (BCVA) were also measured. Regression analyses assessed the contribution of astigmatism (J0) and HOAs to BCVA. Results The mean root-mean-square (RMS) HOA of 0.191 ± 0.072 μm was significantly greater than population norms (0.100 ± 0.044 μm. All unsigned HOA coefficients (z06u to z14u) and all signed coefficients except z09s, z10s, and z11s were significantly larger than population norms. Decreased BCVA was associated with astigmatism (J0) and spherical aberration (z12u) but not RMS coma, with the effect of J0 about 4 times as great as z12u. Conclusions Tohono O’odham children show elevated HOAs compared to population norms. Astigmatism and unsigned spherical aberration are associated with decreased acuity, but the effects of spherical aberration are minimal and not clinically significant. PMID:26239206

  15. Complete Au@ZnO core-shell nanoparticles with enhanced plasmonic absorption enabling significantly improved photocatalysis

    NASA Astrophysics Data System (ADS)

    Sun, Yiqiang; Sun, Yugang; Zhang, Tao; Chen, Guozhu; Zhang, Fengshou; Liu, Dilong; Cai, Weiping; Li, Yue; Yang, Xianfeng; Li, Cuncheng

    2016-05-01

    Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic

  16. Combat-Related Intradural Gunshot Wound to the Thoracic Spine: Significant Improvement and Neurologic Recovery Following Bullet Removal

    PubMed Central

    Louwes, Thijs M; Ward, William H; Lee, Kendall H

    2015-01-01

    The vast majority of combat-related penetrating spinal injuries from gunshot wounds result in severe or complete neurological deficit. Treatment is based on neurological status, the presence of cerebrospinal fluid (CSF) fistulas, and local effects of any retained fragment(s). We present a case of a 46-year-old male who sustained a spinal gunshot injury from a 7.62-mm AK-47 round that became lodged within the subarachnoid space at T9-T10. He immediately suffered complete motor and sensory loss. By 24-48 hours post-injury, he had recovered lower extremity motor function fully but continued to have severe sensory loss (posterior cord syndrome). On post-injury day 2, he was evacuated from the combat theater and underwent a T9 laminectomy, extraction of the bullet, and dural laceration repair. At surgery, the traumatic durotomy was widened and the bullet, which was laying on the dorsal surface of the spinal cord, was removed. The dura was closed in a water-tight fashion and fibrin glue was applied. Postoperatively, the patient made a significant but incomplete neurological recovery. His stocking-pattern numbness and sub-umbilical searing dysthesia improved. The spinal canal was clear of the foreign body and he had no persistent CSF leak. Postoperative magnetic resonance imaging of the spine revealed contusion of the spinal cord at the T9 level. Early removal of an intra-canicular bullet in the setting of an incomplete spinal cord injury can lead to significant neurological recovery following even high-velocity and/or high-caliber gunshot wounds. However, this case does not speak to, and prior experience does not demonstrate, significant neurological benefit in the setting of a complete injury. PMID:25705346

  17. A Matter of Timing: Identifying Significant Multi-Dose Radiotherapy Improvements by Numerical Simulation and Genetic Algorithm Search

    PubMed Central

    Angus, Simon D.; Piotrowska, Monika Joanna

    2014-01-01

    -effecitive means of significantly improving clinical efficacy. PMID:25460164

  18. Night vision goggle visual acuity assessment: results of an interagency test

    NASA Astrophysics Data System (ADS)

    Task, H. Lee

    2001-08-01

    There are several parameters that are used to characterize the quality of a night vision goggle (NVG) such as resolution, gain, field-of-view, visual acuity, etc. One of the primary parameters is visual acuity or resolution of the NVG. These two terms are often used interchangeably primarily because of the measurement methods employed. The objectives of this paper are to present: (1) an argument as to why NVG visual acuity and resolution should be considered as distinctly different parameters, (2) descriptions of different methods of measuring visual acuity and resolution, and (3) the results of a blind test by several agencies to measure the resolution of the same two NVGs (four oculars).

  19. Ocular motility, visual acuity and dysfunction of neuropsychological impairment in children with shunted uncomplicated hydrocephalus.

    PubMed

    Zeiner, H K; Prigatano, G P; Pollay, M; Biscoe, C B; Smith, R V

    1985-01-01

    Children with shunted, uncomplicated, communicating hydrocephalus were tested to determine (1) the persistence of neuropsychological impairment and (2) the relationship between neuropsychological functioning, ocular motility, and acuity abnormalities. Eighteen hydrocephalic and 18 individually age- and sex-matched controls were given a neuropsychological battery, repeated after an interval of 1 year. Hydrocephalic children were also tested at the beginning of the second year for strabismus, amblyopia and visual acuity. Their medical records were reviewed for history of ocular motility and/or acuity abnormalities. Hydrocephalic children with normal range IQ were found to have lower verbal IQ, memory, and fine motor skills compared to controls. A history of ocular motility and acuity abnormalities was associated with impaired visuospatial and verbal problem-solving skills. PMID:4005882

  20. A Taste-intensity Visual Analog Scale: An Improved Zinc Taste-test Protocol

    PubMed Central

    Zdilla, Matthew J.; Starkey, Leah D.; Saling, Julia R.

    2015-01-01

    Context Studies employing methods for measurement of zinc sulfate taste acuity have had diverse results, and although the studies have had limitations in design and implementation, they have suggested salient findings beyond the assessment of taste acuity. These findings have included, but were not limited to, relationships between zinc sulfate taste acuity and weight, levels of serum zinc, diastolic hypertension, levels of salivary carbonic anhydrase 6, and frequency of illness. However, current protocols for zinc sulfate taste assessment are problematic and warrant improvement. Objective The current study intended to compare the ranking scale for the original Bryce-Smith and Simpson zinc taste test (BS-ZTT) with a novel, taste-intensity visual analog scale (TI-VAS) to explore the potential for improved zinc sulfate taste-acuity measurement. Design Participants were administered a 0.1% solution of zinc sulfate and assessed using the 2 scales. Setting The study took place at West Liberty University, in West Liberty, WV, USA. Participants Participants were 500 West Liberty University students who volunteered to participate in the study. Results A strong, statistically significant, positive correlation existed between the BS-ZTT and the TI-VAS scores (rs = 0.79; P < .0001; n = 491). Conclusions The study found that the BS-ZTT offered a limited number of ordinal variable ranks and depended on an examiner’s evaluation. Conversely, the TI-VAS had an expanded range of variables and was independent of the examiner. The TI-VAS can be used as a taste-acuity test for zinc sulfate and as a benchmark for future analyses of zinc sulfate taste acuity and zinc taste tests. PMID:26770137

  1. An ensemble strategy that significantly improves de novo assembly of microbial genomes from metagenomic next-generation sequencing data

    PubMed Central

    Deng, Xutao; Naccache, Samia N.; Ng, Terry; Federman, Scot; Li, Linlin; Chiu, Charles Y.; Delwart, Eric L.

    2015-01-01

    Next-generation sequencing (NGS) approaches rapidly produce millions to billions of short reads, which allow pathogen detection and discovery in human clinical, animal and environmental samples. A major limitation of sequence homology-based identification for highly divergent microorganisms is the short length of reads generated by most highly parallel sequencing technologies. Short reads require a high level of sequence similarities to annotated genes to confidently predict gene function or homology. Such recognition of highly divergent homologues can be improved by reference-free (de novo) assembly of short overlapping sequence reads into larger contigs. We describe an ensemble strategy that integrates the sequential use of various de Bruijn graph and overlap-layout-consensus assemblers with a novel partitioned sub-assembly approach. We also proposed new quality metrics that are suitable for evaluating metagenome de novo assembly. We demonstrate that this new ensemble strategy tested using in silico spike-in, clinical and environmental NGS datasets achieved significantly better contigs than current approaches. PMID:25586223

  2. Novel ventilation design of combining spacer and mesh structure in sports T-shirt significantly improves thermal comfort.

    PubMed

    Sun, Chao; Au, Joe Sau-chuen; Fan, Jintu; Zheng, Rong

    2015-05-01

    This paper reports on novel ventilation design in sports T-shirt, which combines spacer and mesh structure, and experimental evidence on the advantages of design in improving thermal comfort. Evaporative resistance (Re) and thermal insulation (Rc) of T-shirts were measured using a sweating thermal manikin under three different air velocities. Moisture permeability index (i(m)) was calculated to compare the different designed T-shirts. The T-shirts of new and conventional designs were also compared by wearer trials, which were comprised of 30 min treadmill running followed by 10 min rest. Skin temperature, skin relative humidity, heart rate, oxygen inhalation and energy expenditure were monitored, and subjective sensations were asked. Results demonstrated that novel T-shirt has 11.1% significant lower im than control sample under windy condition. The novel T-shirt contributes to reduce the variation of skin temperature and relative humidity up to 37% and 32%, as well as decrease 3.3% energy consumption during exercise. PMID:25683541

  3. First significant image improvement from a sodium-layer laser guide star adaptive optics system at Lick Observatory

    SciTech Connect

    Olivier, S.S.; Max, C.E.; Friedman, H.W.; An, J.; Avicola, K.; Beeman, B.V.; Bissinger, H.D.; Brase, J.M.; Erbert, G.V.; Gavel, D.T.; Kanz, K.; Macintosh, B.; Neeb, K.P.; Waltjen, K.E.

    1997-07-14

    Atmospheric turbulence severely limits the resolution of ground-based telescopes. Adaptive optics can correct for the aberrations caused by the atmosphere, but requires a bright wavefront reference source in close angular proximity to the object being imaged. Since natural reference stars of the necessary brightness are relatively rare, methods of generating artificial reference beacons have been under active investigation for more than a decade. In this paper, we report the first significant image improvement achieved using a sodium-layer laser guide star as a wavefront reference for a high- order adaptive optics system. An artificial beacon was created by resonant scattering from atomic sodium in the mesosphere, at an altitude of 95 km. Using this laser guide star, an adaptive optics system on the 3 m Shane Telescope at Lick Observatory produced a factor of 2.4 increase in peak intensity and a factor of 2 decrease in full width at half maximum of a stellar image, compared with image motion compensation alone. The Strehl ratio when using the laser guide star as the reference was 65% of that obtained with a natural guide star, and the image full widths at half maximum were identical, 0.3 arc sec, using either the laser or the natural guide star. This sodium-layer laser guide star technique holds great promise for the world`s largest telescopes. 24 refs., 4 figs., 1 tab.

  4. Proposed fish passage improvements at Three Mile Falls Diversion Dam, Umatilla River, Oregon: Finding of no significant impact

    SciTech Connect

    Not Available

    1986-05-01

    The Bureau of Reclamation proposes to administer the construction of fish passage and protective facilities at Three Mile Falls Diversion Dam on the Umatilla River in Oregon to increase the numbers of anadromous fish. The Bonneville Power Administration (BPA) proposes to provide funding for the project. These agencies' actions would implement section 904(d) of the Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program which addresses the provision of offsite enhancement to compensate for fish and wildlife losses caused by hydroelectric project development and operations throughout the Columbia River Basin. This Finding of No Significant Impact (FONSI) is the National Environmental Policy Act (NEPA) decision document for both agencies. The proposed action would improve both upstream and downstream passage by providing a new right bank ladder on Three Mile Falls Diversion Dam, modifying the existing left bank ladder, and installing rotary drum fish screens and related structures on the adjacent West Extension Irrigation District (WEID) Canal. Four other alternatives are considered in the environmental assessment (EA): a concrete apron plus a left bank ladder; a cap on the crest of the dam plus a left bank ladder; dam removal; and no action. 5 figs., 6 tabs.

  5. The Effect of State Medicaid Case-Mix Payment on Nursing Home Resident Acuity

    PubMed Central

    Feng, Zhanlian; Grabowski, David C; Intrator, Orna; Mor, Vincent

    2006-01-01

    Objective To examine the relationship between Medicaid case-mix payment and nursing home resident acuity. Data Sources Longitudinal Minimum Data Set (MDS) resident assessments from 1999 to 2002 and Online Survey Certification and Reporting (OSCAR) data from 1996 to 2002, for all freestanding nursing homes in the 48 contiguous U.S. states. Study Design We used a facility fixed-effects model to examine the effect of introducing state case-mix payment on changes in nursing home case-mix acuity. Facility acuity was measured by aggregating the nursing case-mix index (NCMI) from the MDS using the Resource Utilization Group (Version III) resident classification system, separately for new admits and long-stay residents, and by an OSCAR-derived index combining a range of activity of daily living dependencies and special treatment measures. Data Collection/Extraction Methods We followed facilities over the study period to create a longitudinal data file based on the MDS and OSCAR, respectively, and linked facilities with longitudinal data on state case-mix payment policies for the same period. Principal Findings Across three acuity measures and two data sources, we found that states shifting to case-mix payment increased nursing home acuity levels over the study period. Specifically, we observed a 2.5 percent increase in the average acuity of new admits and a 1.3 to 1.4 percent increase in the acuity of long-stay residents, following the introduction of case-mix payment. Conclusions The adoption of case-mix payment increased access to care for higher acuity Medicaid residents. PMID:16899009

  6. Significant Improvement of Puncture Accuracy and Fluoroscopy Reduction in Percutaneous Transforaminal Endoscopic Discectomy With Novel Lumbar Location System

    PubMed Central

    Fan, Guoxin; Guan, Xiaofei; Zhang, Hailong; Wu, Xinbo; Gu, Xin; Gu, Guangfei; Fan, Yunshan; He, Shisheng

    2015-01-01

    Abstract Prospective nonrandomized control study. The study aimed to investigate the implication of the HE's Lumbar LOcation (HELLO) system in improving the puncture accuracy and reducing fluoroscopy in percutaneous transforaminal endoscopic discectomy (PTED). Percutaneous transforaminal endoscopic discectomy is one of the most popular minimally invasive spine surgeries that heavily depend on repeated fluoroscopy. Increased fluoroscopy will induce higher radiation exposure to surgeons and patients. Accurate puncture in PTED can be achieved by accurate preoperative location and definite trajectory. The HELLO system mainly consists of self-made surface locator and puncture-assisted device. The surface locator was used to identify the exact puncture target and the puncture-assisted device was used to optimize the puncture trajectory. Patients who had single L4/5 or L5/S1 lumbar intervertebral disc herniation and underwent PTED were included the study. Patients receiving the HELLO system were assigned in Group A, and those taking conventional method were assigned in Group B. Study primary endpoint was puncture times and fluoroscopic time, and the secondary endpoint was location time and operation time. A total of 62 patients who received PTED were included in this study. The average age was 45.35 ± 8.70 years in Group A and 46.61 ± 7.84 years in Group B (P = 0.552). There were no significant differences in gender, body mass index, conservative time, and surgical segment between the 2 groups (P > 0.05). The puncture time(s) were 1.19 ± 0.48 in Group A and 6.03 ± 1.87 in Group B (P < 0.001). The fluoroscopic times were 14.03 ± 2.54 in Group A and 25.19 ± 4.28 in Group B (P < 0.001). The preoperative location time was 4.67 ± 1.41 minutes in Group A and 6.98 ± 0.94 minutes in Group B (P < 0.001). The operation time was 79.42 ± 10.15 minutes in Group A and 89.65 ± 14.06 minutes in Group B (P

  7. Interocular Shift of Visual Attention Enhances Stereopsis and Visual Acuities of Anisometropic Amblyopes beyond the Critical Period of Visual Development: A Novel Approach

    PubMed Central

    Huang, Liwen; Sun, Xinghuai; Liu, Shuai; Liu, Rui; Mansouri, Behzad; Wong, Vicky wing lai; Wen, Wen; Liu, Hong; Wang, Ai-Hou

    2014-01-01

    Aims. Increasing evidence shows that imbalanced suppressive drive prior to binocular combination may be the key factor in amblyopia. We described a novel binocular approach, interocular shift of visual attention (ISVA), for treatment of amblyopia in adult patients. Methods. Visual stimuli were presented anaglyphically on a computer screen. A square target resembling Landolt C had 2 openings, one in red and one in cyan color. Through blue-red goggles, each eye could only see one of the two openings. The patient was required to report the location of the opening presented to the amblyopic eye. It started at an opening size of 800 sec of arc, went up and down in 160 sec of arc step, and stopped when reaching the 5th reversals. Ten patients with anisometropic amblyopia older than age 14 (average age: 26.7) were recruited and received ISVA treatment for 6 weeks, with 2 training sessions per day. Results. Both Titmus stereopsis (z = −2.809, P = 0.005) and Random-dot stereopsis (z = −2.317, P = 0.018) were significantly improved. Average improvement in best corrected visual acuity (BCVA) was 0.74 line (t = 5.842, P < 0.001). Conclusions. The ISVA treatment may be effective in treating amblyopia and restoring stereoscopic function. PMID:25580280

  8. Development of Polarizable Models for Molecular Mechanical Calculations II: Induced Dipole Models Significantly Improve Accuracy of Intermolecular Interaction Energies

    PubMed Central

    Wang, Junmei; Cieplak, Piotr; Li, Jie; Wang, Jun; Cai, Qin; Hsieh, MengJuei; Lei, Hongxing; Luo, Ray; Duan, Yong

    2011-01-01

    In the companion paper, we presented a set of induced dipole interaction models using four types of screening functions, which include the Applequist (no screening), the Thole linear, the Thole exponential model, and the Thole Tinker-like (another form of exponential screening function) functions. In this work, we evaluate the performance of polarizability models using large set of amino acid analog pairs that are frequently observed in protein structures as a benchmark. For each amino acid pair we calculated quantum mechanical interaction energies at the MP2/aug-cc-pVTZ//MP2/6-311++G(d,p) level with the basis set superposition error (BSSE) correction and compared them with molecular mechanics results. Encouragingly, all the polarizable models significantly outperform the additive F94 and F03 models (mimicking AMBER ff94/ff99 and ff03 force fields, respectively) in reproducing the BSSE-corrected quantum mechanical interaction energies. Particularly, the root-mean-square errors (RMSE) for three Thole models in Set A (where the 1–2 and 1–3 interactions are turned off and all 1–4 interactions are included) are 1.456, 1.417 and 1.406 kcal/mol for Model AL (Thole Linear), Model AE (Thole exponential) and Model AT (Thole Tinker-like), respectively. In contrast, the RMSE are 3.729 and 3.433 kcal/mol for F94 and F03 models, respectively. A similar trend was observed for the average unsigned errors (AUE), which are 1.057, 1.025, 1.011, 2.219 and 2.070 kcal/mol for AL, AE, AT, F94/ff99 and F03, respectively. Analyses based on the trend line slopes indicate that the two fixed charge models substantially underestimate the relative strengths of non-charge-charge interactions by 24% (F03) and 35% (F94), respectively, whereas the four polarizable models over-estimate the relative strengths by 5% (AT), 3% (AL, AE) and 13% (AA), respectively. Agreement was further improved by adjusting the van der Waals parameters. Judging from the notably improved accuracy in comparison to

  9. Development of polarizable models for molecular mechanical calculations II: induced dipole models significantly improve accuracy of intermolecular interaction energies.

    PubMed

    Wang, Junmei; Cieplak, Piotr; Li, Jie; Wang, Jun; Cai, Qin; Hsieh, MengJuei; Lei, Hongxing; Luo, Ray; Duan, Yong

    2011-03-31

    In the companion paper, we presented a set of induced dipole interaction models using four types of screening functions, which include the Applequist (no screening), the Thole linear, the Thole exponential model, and the Thole Tinker-like (another form of exponential screening function) functions. In this work, we evaluate the performance of polarizability models using a large set of amino acid analog pairs in conformations that are frequently observed in protein structures as a benchmark. For each amino acid pair, we calculated quantum mechanical interaction energies at the MP2/aug-cc-pVTZ//MP2/6-311++G(d,p) level with the basis set superposition error (BSSE) correction and compared them with molecular mechanics results. Encouragingly, all polarizable models significantly outperform the additive F94 and F03 models (mimicking AMBER ff94/ff99 and ff03 force fields, respectively) in reproducing the BSSE-corrected quantum mechanical interaction energies. In particular, the root-mean-square errors (RMSEs) for three Thole models in Set A (where the 1-2 and 1-3 interactions are turned off and all 1-4 interactions are included) are 1.456, 1.417, and 1.406 kcal/mol for model AL (Thole Linear), model AE (Thole exponential), and model AT (Thole Tinker-like), respectively. In contrast, the RMSEs are 3.729 and 3.433 kcal/mol for F94 and F03 models, respectively. A similar trend was observed for the average unsigned errors (AUEs), which are 1.057, 1.025, 1.011, 2.219, and 2.070 kcal/mol for AL, AE, AT, F94/ff99, and F03, respectively. Analyses based on the trend line slopes indicate that the two fixed charge models substantially underestimate the relative strengths of noncharge-charge interactions by 24 (F03) and 35% (F94), respectively, whereas the four polarizable models overestimate the relative strengths by 5 (AT), 3 (AL, AE), and 13% (AA), respectively. Agreement was further improved by adjusting the van der Waals parameters. Judging from the notably improved accuracy in

  10. Outcomes of visual acuity in carbon ion radiotherapy: Analysis of dose-volume histograms and prognostic factors

    SciTech Connect

    Hasegawa, Azusa . E-mail: azusa@nirs.go.jp; Mizoe, Jun-etsu; Mizota, Atsushi; Tsujii, Hirohiko

    2006-02-01

    Purpose: To analyze the tolerance dose for retention of visual acuity in patients with head-and-neck tumors treated with carbon ion radiotherapy. Methods and Materials: From June 1994 to March 2000, 163 patients with tumors in the head and neck or skull base region were treated with carbon ion radiotherapy. Analysis was performed on 54 optic nerves (ONs) corresponding to 30 patients whose ONs had been included in the irradiated volume. These patients showed no evidence of visual impairment due to other factors and had a follow-up period of >4 years. All patients had been informed of the possibility of visual impairment before treatment. We evaluated the dose-complication probability and the prognostic factors for the retention of visual acuity in carbon ion radiotherapy, using dose-volume histograms and multivariate analysis. Results: The median age of 30 patients (14 men, 16 women) was 57.2 years. Median prescribed total dose was 56.0 gray equivalents (GyE) at 3.0-4.0 GyE per fraction per day (range, 48-64 GyE; 16-18 fractions; 4-6 weeks). Of 54 ONs that were analyzed, 35 had been irradiated with <57 GyE (maximum dose [D{sub max}]) resulting in no visual loss. Conversely, 11 of the 19 ONs (58%) irradiated with >57 GyE (D{sub max}) suffered a decrease of visual acuity. In all of these cases, the ONs had been involved in the tumor before carbon ion radiotherapy. In the multivariate analysis, a dose of 20% of the volume of the ON (D{sub 2}) was significantly associated with visual loss. Conclusions: The occurrence of visual loss seems to be correlated with a delivery of >60 GyE to 20% of the volume of the ON.

  11. Decrease of global methylation improves significantly hepatic differentiation of Ad-MSCs: possible future application for urea detoxification.

    PubMed

    Seeliger, C; Culmes, M; Schyschka, L; Yan, X; Damm, G; Wang, Z; Kleeff, J; Thasler, W E; Hengstler, J; Stöckle, U; Ehnert, S; Nüssler, A K

    2013-01-01

    Hepatocyte transplantation is considered to be an alternative to orthotopic liver transplantation. Cells can be used to bridge patients waiting for a donor organ, decrease mortality in acute liver failure, and support metabolic liver diseases. The limited availability of primary human hepatocytes for such applications has led to the generation of alternative hepatocyte-like cells from various adult stem or precursor cells. The aim of this study was to generate hepatocyte-like cells from adipose-derived mesenchymal stem cells (Ad-MSCs) for clinical applications, which are available "off the shelf." Epigenetic changes in hepatocyte-like cells were induced by 5-azacytidine, which, in combination with other supplements, leads to significantly improved metabolic and enzymatic activities compared to nontreated cells. Cells with sufficient hepatic features were generated with a four-step protocol: 5-azacytidine (step 1); epidermal growth factor (step 2); fibroblast growth factor-4, dexamethasone, insulin-transferrin-sodium-selenite, and nicotinamide (step 3); and hepatocyte growth factor, dexamethasone, insulin-transferrin-sodium-selenite, and nicotinamide (step 4). Generated differentiated cells had higher phase I (CYP1A1/2, CYP2E1, CYP2B6, CYP3A4) and phase II activities compared to the undifferentiated cells. A strong expression of CYP3A7 and a weak expression of 3A4, as well as the important detoxification markers α-fetoprotein and albumin, could also be detected at the mRNA level. Importantly, urea metabolism (basal, NH4-stimulated, NH4- and ornithine-stimulated) was comparable to freshly isolated human hepatocytes, and unlike cryopreserved human hepatocytes, this activity was maintained after 6 months of cryopreservation. These findings suggest that these cells may be suitable for clinical application, especially for treatment of urea cycle disorders. PMID:22507189

  12. Delayed Administration of Bone Marrow Mesenchymal Stem Cell Conditioned Medium Significantly Improves Outcome After Retinal Ischemia in Rats

    PubMed Central

    Dreixler, John C.; Poston, Jacqueline N.; Balyasnikova, Irina; Shaikh, Afzhal R.; Tupper, Kelsey Y.; Conway, Sineadh; Boddapati, Venkat; Marcet, Marcus M.; Lesniak, Maciej S.; Roth, Steven

    2014-01-01

    Purpose. Delayed treatment after ischemia is often unsatisfactory. We hypothesized that injection of bone marrow stem cell (BMSC) conditioned medium after ischemia could rescue ischemic retina, and in this study we characterized the functional and histological outcomes and mechanisms of this neuroprotection. Methods. Retinal ischemia was produced in adult Wistar rats by increasing intraocular pressure for 55 minutes. Conditioned medium (CM) from rat BMSCs or unconditioned medium (uCM) was injected into the vitreous 24 hours after the end of ischemia. Recovery was assessed 7 days after ischemia using electroretinography, at which time we euthanized the animals and then prepared 4-μm-thick paraffin-embedded retinal sections. TUNEL and Western blot were used to identify apoptotic cells and apoptosis-related gene expression 24 hours after injections; that is, 48 hours after ischemia. Protein content in CM versus uCM was studied using tandem mass spectrometry, and bioinformatics methods were used to model protein interactions. Results. Intravitreal injection of CM 24 hours after ischemia significantly improved retinal function and attenuated cell loss in the retinal ganglion cell layer. CM attenuated postischemic apoptosis and apoptosis-related gene expression. By spectral counting, 19 proteins that met stringent identification criteria were increased in the CM compared to uCM; the majority were extracellular matrix proteins that mapped into an interactional network together with other proteins involved in cell growth and adhesion. Conclusions. By restoring retinal function, attenuating apoptosis, and preventing retinal cell loss after ischemia, CM is a robust means of delayed postischemic intervention. We identified some potential candidate proteins for this effect. PMID:24699381

  13. [A CASE OF ADVANCED BLADDER NEUROENDOCRINE CARCINOMA (SMALL CELL CARCINOMA) SIGNIFICANTLY IMPROVED BY LOW DOSE OF ORAL TEGAFUR-URACIL].

    PubMed

    Nomi, Hayahito; Takahara, Kiyoshi; Minami, Koichiro; Maenosono, Ryoichi; Matsunaga, Tomohisa; Yoshikawa, Yuki; Tsujino, Takuya; Hirano, Hajime; Inamoto, Teruo; Yamamoto, Ikuhisa; Tsuji, Motomu; Kiyama, Satoshi; Azuma, Haruhito

    2015-10-01

    A 81-old-woman underwent a transurethral resection of bladder tumor (TURBT) at a nearby hospital in April 2011. The diagnosis was invasive urothelial carcinoma, G3 with a component of bladder small cell carcinoma, T1 or more. She was recommended to visit our hospital for combined modality therapy of bladder cancer, but she refused the treatment for over one year. In May 2012, she came to our hospital with the chief complaint of pain at urination. Cystoscopy revealed non-papillary sessile tumor in the top of the bladder, and CT scan demonstrated the presence of the right obturator lymph nodes swollen up to 1.2 cm in size. The second TURBT was performed and the diagnosis was bladder small cell carcinoma (pT3N2M0) according to urothelial cancer guidelines of the Japanese Urological Association (JUA). Because she strongly refused hospitalization anymore, we started daily oral intake of low dose Tegafur-Uracil (100 mg) for the treatment. After one month, the serum Neuron-Specific Enolase (NSE; tumor maker of small cell cancer) level was elevated to 27.6 ng/ml and the right obturator lymph node was enlarged up to 1.9 cm. Therefore, the Trgafur-Uracil dose was increased to 200 mg daily. After then, the serum NSE level was decreased to 15.5 ng/ml following reduction in size of the obturator lymph nodes with partial response in December 2013. After two years of follow-up period, her regular urine test showed normal findings, and no apparent recurrence was detected on urinary bladder with MRI and Cystoscopy. This is a case of advanced bladder small cell carcinoma significantly improved by oral administration of Tegafur-Uracil 200 mg/day for over 2 years. PMID:26717786

  14. Associations of Anisometropia with Unilateral Amblyopia, Interocular Acuity Difference and Stereoacuity in Preschoolers

    PubMed Central

    Ying, Gui-shuang; Huang, Jiayan; Maguire, Maureen; Quinn, Graham; Kulp, Marjean Taylor; Ciner, Elise; Cyert, Lynn; Orel-Bixler, Deborah

    2012-01-01

    Purpose To evaluate the relation of anisometropia with unilateral amblyopia, interocular acuity difference (IAD) and stereoacuity, among Head Start preschoolers, using both clinical notation and vector notation analyses. Design Multicenter, cross-sectional study. Participants 3- to 5-year-old participants in the Vision In Preschoolers (VIP) Study (N=4040). Methods Secondary analysis of VIP data from participants who had comprehensive eye examinations including monocular visual acuity (VA) testing, stereoacuity testing, and cycloplegic refraction. VA was retested with full cycloplegic correction when retest criteria were met. Unilateral amblyopia was defined as IAD ≥2 lines in logarithm of the Minimum Angle of Resolution (logMAR). Anisometropia was defined as ≥0.25 D (diopter) difference in spherical equivalent (SE) or in cylinder power, and also two approaches using power vector notation. The percentage with unilateral amblyopia, mean IAD, and mean stereoacuity were compared between anisometropic and isometropic children. Main Outcomes Measures The percentage with unilateral amblyopia, mean IAD, and mean stereoacuity. Results Compared with isometropic children, anisometropic children had a higher percentage of unilateral amblyopia (8% vs. 2%), larger mean IAD (0.07 vs. 0.05 logMAR) and worse mean stereoacuity (145 vs.117 arc sec) (all p<0.0001). Larger amounts of anisometropia were associated with higher percentages of unilateral amblyopia, larger IAD, and worse stereoacuity (trend p<0.001). Percentage of unilateral amblyopia was significantly increased with spherical equivalent (SE) anisometropia >0.5 D, cylindrical anisometropia >0.25 D, the vertical/horizontal meridian (J0) or oblique meridian (J45) >0.125 D, or vector dioptric distance (VDD) >0.35 D (all p<0.001). VDD had higher ability in detecting unilateral amblyopia than cylinder, SE, J0 and J45 (p<0.001). Conclusions The presence of and amount of anisometropia were associated with the presence of

  15. 'Correctable undetected visual acuity deficit' in patients aged 65 and over attending an accident and emergency department.

    PubMed Central

    Reinstein, D Z; Dorward, N L; Wormald, R P; Graham, A; O'Connor, I; Charlton, R M; Yeatman, M; Dodenhoff, R; Touquet, R; Challoner, T

    1993-01-01

    The rate of occurrence of correctable undetected visual acuity deficit (CUVAD) in a population of patients aged 65 and over was investigated, using a pinhole screening method, to compare the sociodemographic and optical eye care habits of patients with or without a functionally significant CUVAD. Of 136 patients 46 (34%) were found to have a functionally significant CUVAD in one or both eyes which was not significantly associated with optician or general practitioner contact, age, sex, social class, living situation, or number of medications. Half the patients with significant CUVAD had not attended for 2 years mainly because of financial considerations. Three quarters attended of their own volition; only one in seven were prompted by opticians' postal invitations. It was concluded that a significant degree of CUVAD could be detected using a simple procedure which can be carried out by general practitioners as part of their general elderly health screen. PMID:8318466

  16. Individual Differences in Scotopic Visual Acuity and Contrast Sensitivity: Genetic and Non-Genetic Influences

    PubMed Central

    Bartholomew, Alex J.; Lad, Eleonora M.; Cao, Dingcai; Bach, Michael; Cirulli, Elizabeth T.

    2016-01-01

    Despite the large amount of variation found in the night (scotopic) vision capabilities of healthy volunteers, little effort has been made to characterize this variation and factors, genetic and non-genetic, that influence it. In the largest population of healthy observers measured for scotopic visual acuity (VA) and contrast sensitivity (CS) to date, we quantified the effect of a range of variables on visual performance. We found that young volunteers with excellent photopic vision exhibit great variation in their scotopic VA and CS, and this variation is reliable from one testing session to the next. We additionally identified that factors such as Circadian preference, iris color, astigmatism, depression, sex and education have no significant impact on scotopic visual function. We confirmed previous work showing that the amount of time spent on the vision test influences performance and that laser eye surgery results in worse scotopic vision. We also showed a significant effect of intelligence and photopic visual performance on scotopic VA and CS, but all of these variables collectively explain <30% of the variation in scotopic vision. The wide variation seen in young healthy volunteers with excellent photopic vision, the high test-retest agreement, and the vast majority of the variation in scotopic vision remaining unexplained by obvious non-genetic factors suggests a strong genetic component. Our preliminary genome-wide association study (GWAS) of 106 participants ruled out any common genetic variants of very large effect and paves the way for future, larger genetic studies of scotopic vision. PMID:26886100

  17. The Correlation of Age and Postoperative Visual Acuity for Age-Related Cataract

    PubMed Central

    Li, Xiaochun; Cao, Xiaoguang; Hou, Xianru; Bao, Yongzhen

    2016-01-01

    Purpose. Clinically, what is the best time for age-related cataract (ARC) patients to receive surgeries and get the most benefits is important. We explored the relationship between age and presenting postoperative visual acuity (POVA) in patients from rural China. Methods. Three Lifeline Express Hospital Eye-Train missions of Peking University People's Hospital were chosen. At the first day after surgery, 3452 ARC eyes with the presenting POVA ≥ 6/60 were enrolled. The relationship between age and POVA was analyzed statistically. Results. In these three missions, there were more female patients than males; the ratio of females to males was 1.71. The average age of females was older than males. Overall, the percentages of patients with good visual outcomes (≥6/18) were significantly decreased with aging. Different regions had variations, but the trends were the same. There was weak linear correlation between age and POVA. The correlations of females were stronger than males in Yuncheng and Sanmenxia and weaker than males in Zhoukou. Conclusion. The good visual outcomes of presenting POVA were significantly decreased with aging and there were weak linear correlations between age and POVA in rural China. The linear correlation might be influenced by the difference of gender and region. PMID:26881225

  18. Individual Differences in Scotopic Visual Acuity and Contrast Sensitivity: Genetic and Non-Genetic Influences.

    PubMed

    Bartholomew, Alex J; Lad, Eleonora M; Cao, Dingcai; Bach, Michael; Cirulli, Elizabeth T

    2016-01-01

    Despite the large amount of variation found in the night (scotopic) vision capabilities of healthy volunteers, little effort has been made to characterize this variation and factors, genetic and non-genetic, that influence it. In the largest population of healthy observers measured for scotopic visual acuity (VA) and contrast sensitivity (CS) to date, we quantified the effect of a range of variables on visual performance. We found that young volunteers with excellent photopic vision exhibit great variation in their scotopic VA and CS, and this variation is reliable from one testing session to the next. We additionally identified that factors such as Circadian preference, iris color, astigmatism, depression, sex and education have no significant impact on scotopic visual function. We confirmed previous work showing that the amount of time spent on the vision test influences performance and that laser eye surgery results in worse scotopic vision. We also showed a significant effect of intelligence and photopic visual performance on scotopic VA and CS, but all of these variables collectively explain <30% of the variation in scotopic vision. The wide variation seen in young healthy volunteers with excellent photopic vision, the high test-retest agreement, and the vast majority of the variation in scotopic vision remaining unexplained by obvious non-genetic factors suggests a strong genetic component. Our preliminary genome-wide association study (GWAS) of 106 participants ruled out any common genetic variants of very large effect and paves the way for future, larger genetic studies of scotopic vision. PMID:26886100

  19. Effect of Passive Horizontal Rotations and Vertical Oscillations on Dynamic Visual Acuity

    NASA Technical Reports Server (NTRS)

    Mulavara, Ajitkumar; Peters, Brian; Wood, Scott; Cohen, Helen; Kulecz, Walter B.; Miller, Chris; Reschke, Millard; Bloomberg, Jacob

    2010-01-01

    Astronauts experience sensorimotor disturbances after long duration space flight. These crewmembers may need to egress the vehicle within a few minutes for safety and operational reasons in various sea state conditions following a water landing. Exposure to even low frequency motions induced by sea conditions surrounding a vessel can cause significant fine and gross motor control problems affecting critical functions. The objective of this study was to document human motor and visual performance during simulated wave motion in the 0.1 to 2.0 Hz range. We examined in 12 healthy subjects the changes in accuracy when performing a seated visual target acquisition task in which the location of target was offset vertically during horizontal full body rotation at an oscillating frequency of 0.8 Hz (peak velocity of 160 deg/s). The main finding was that the accuracy of performance degraded in 7 of 12 subjects when acquiring vertical targets at perturbing frequencies of 0.8 Hz in the horizontal plane by one step size. We also examined in a separate study on 12 healthy subjects seated dynamic visual acuity (DVA) task performance during vertical full body oscillations at perturbing frequencies of 2 Hz (peak to peak motion of 5 cm). The main finding was that DVA was significantly reduced when acquiring targets at perturbing oscillations at frequencies of 2 Hz in the vertical plane by approximately 1 chart line. Thus low frequencies of perturbations in the horizontal and vertical planes can cause decrement in visual performance.

  20. Early Quick Acuity Score Provides More Complete Data on Emergency Department Walkouts

    PubMed Central

    Lovett, Paris B.; Kahn, J. Akiva; Greene, Stuart E.; Bloch, Matthew A.; Brandt, Daniel R.; Minckler, Michael R.

    2014-01-01

    Introduction Many prior studies have compared the acuity of Emergency Department (ED) patients who have Left Without Being Seen (LWBS) against non-LWBS patients. A weakness in these studies is that patients may walk out prior to the assignment of a triage score, biasing comparisons. We report an operational change whereby acuity was assessed immediately upon patient arrival. We hypothesized more patients would receive acuity scores with EQAS. We also sought to compare LWBS and non-LWBS patient characteristics with reduced bias. Methods Setting: urban, academic medical center. Retrospective cohort study, electronic chart review, collecting data on all ED patients presenting between 4/1/2010 and 10/31/2011 (“Traditional Acuity Score” period, TAS) and from 11/1/2011 to 3/31/2012 (“Early Quick Acuity Score” period, EQAS). We recorded disposition (LWBS versus non-LWBS), acuity and demographics. For each subject during the EQAS period, we calculated how many prior ED visits and how many prior walkouts the subject had had during the TAS period. Results Acuity was recorded in 92,275 of 94,526 patients (97.6%) for TAS period, and 25,577 of 25,760 patients (99.3%) for EQAS period, a difference of 1.7% (1.5%, 1.8%). LWBS patients had acuity scores recorded in 5,180 of 7,040 cases (73.6%) during TAS period, compared with 897 of 1,010 cases (88.8%) during the EQAS period, a difference of 15.2% (14.8%, 15.7%). LWBS were more likely than non-LWBS to be male, were younger and had lower acuity scores. LWBS averaged 5.3 prior ED visits compared with 2.8 by non-LWBS, a difference of 2.5 (1.5, 3.5). LWBS averaged 1.3 prior ED walkouts compared with 0.2 among non-LWBS, a difference of 1.1 (0.8, 1.3). Conclusions EQAS resulted in a higher proportion of patients receiving acuity scores, particularly among LWBS. This offers more complete data when comparing LWBS and non-LWBS patient characteristics. The comparison reinforced findings from prior studies. PMID:24465699

  1. Understanding Teacher Effectiveness: Significant State Data Capacity Is Required to Measure and Improve Teacher Effectiveness. Data for Action 2012

    ERIC Educational Resources Information Center

    Data Quality Campaign, 2012

    2012-01-01

    States are increasingly focused on understanding and improving teacher effectiveness. There are several funding opportunities that incentivize states to use data to inform measurements of teacher effectiveness. Local, state, and federal efforts support using data to improve teacher preparation programs. Preparation programs seek "access to data…

  2. Comparison of energy expenditure during the Y-balance test in older adults with different visual acuities

    PubMed Central

    Shin, Sun-Shil; An, Duk-Hyun

    2015-01-01

    [Purpose] This study compared the energy expenditure during the Y-balance test (YBT) between elderly women with good binocular visual acuity (BVA) and those with poor BVA. [Subjects] Twenty-one elderly women who could walk independently were recruited from a community dwelling. Eleven participants had a BVA equal to or less than 0.4 logarithm of the minimum angle of resolution (logMAR), and the other 10 participants had a BVA equal to or better than 0.3 logMAR. [Methods] The participants had an accelerometer attached over the L3 spinous process for measurement of energy expenditure and performed the YBT in the anterior, posteromedial, and posterolateral directions. [Results] The normalized reach distance in the good BVA group during the YBT in three directions and composite reach distance were significantly longer compared with the values in the poor BVA group. The energy expenditure in the good BVA group during the YBT in the three directions was significantly reduced compared with the values in the poor BVA group. [Conclusion] We suggest that visual acuity in the elderly influences dynamic balance and energy expenditure. Elderly subjects with poor BVA showed poor dynamic balance control and an inefficient biomechanical cost strategy compared to subjects with good BVA. PMID:25931711

  3. Visual Acuity Using Head-fixed Displays During Passive Self and Surround Motion

    NASA Technical Reports Server (NTRS)

    Wood, Scott J.; Black, F. Owen; Stallings, Valerie; Peters, Brian

    2007-01-01

    The ability to read head-fixed displays on various motion platforms requires the suppression of vestibulo-ocular reflexes. This study examined dynamic visual acuity while viewing a head-fixed display during different self and surround rotation conditions. Twelve healthy subjects were asked to report the orientation of Landolt C optotypes presented on a micro-display fixed to a rotating chair at 50 cm distance. Acuity thresholds were determined by the lowest size at which the subjects correctly identified 3 of 5 optotype orientations at peak velocity. Visual acuity was compared across four different conditions, each tested at 0.05 and 0.4 Hz (peak amplitude of 57 deg/s). The four conditions included: subject rotated in semi-darkness (i.e., limited to background illumination of the display), subject stationary while visual scene rotated, subject rotated around a stationary visual background, and both subject and visual scene rotated together. Visual acuity performance was greatest when the subject rotated around a stationary visual background; i.e., when both vestibular and visual inputs provided concordant information about the motion. Visual acuity performance was most reduced when the subject and visual scene rotated together; i.e., when the visual scene provided discordant information about the motion. Ranges of 4-5 logMAR step sizes across the conditions indicated the acuity task was sufficient to discriminate visual performance levels. The background visual scene can influence the ability to read head-fixed displays during passive motion disturbances. Dynamic visual acuity using head-fixed displays can provide an operationally relevant screening tool for visual performance during exposure to novel acceleration environments.

  4. Presbyopia: a pilot investigation of the barriers and benefits of near visual acuity correction among a rural Filipino population

    PubMed Central

    2014-01-01

    Background Presbyopia is the age-related decline in accommodation that diminishes the ability of the eye to focus on near objects. Presbyopia is common and easy to correct; however, many communities lack access to basic eye care. The purpose of this project was to assess the burden of uncorrected presbyopia in a rural Filipino population and to pilot an intervention aimed at increasing access to reading glasses in the community. Methods Individuals above the age of 40 who presented to a health outreach in the Philippines were invited to undergo a near vision exam to detect the presence of functional presbyopia and be fitted with ready-made, single-vision glasses. The change in stereoacuity was used as a surrogate measure of functional improvement after near vision correction. A questionnaire was administered to assess this population’s perceived barriers and benefits to correcting near vision. Results The average age of the participants was 57 ± 11 years, with 87.6% of participants having an uncorrected near visual acuity of <20/50. Reading glasses improved near vision to 20/40 or better in 77.7% of participants having near-vision impairment (uncorrected near visual acuity of <20/40). Over 75% of participants also showed improvement in stereoacuity. Cost, rather than availability, was perceived to be the greater barrier to the procurement of glasses, and 84% of participants reported that the glasses dispensed would greatly improve their ability to earn a living. Conclusions Dispensing ready-made, single-vision glasses is a simple and cost-effective intervention to improve near vision and enhance depth perception. A greater understanding of the barriers and benefits to correcting near vision will inform the design and execution of a sustainable program to correct presbyopia in developing countries. PMID:24467667

  5. Hydrogen peroxide (H₂O₂) supply significantly improves xanthan gum production mediated by Xanthomonas campestris in vitro.

    PubMed

    Cheng, Rong; Lin, Lin; Zhang, Yongkui

    2012-05-01

    To improve xanthan gum productivity, a strategy of adding hydrogen peroxide (H₂O₂) was studied. The method could intensify oxygen supply through degradation of H₂O₂ to oxygen (O₂). In shake flask testing, the xanthan gum yield reached 2.8% (improved by 39.4%) when adding 12.5 mM H₂O₂ after 24 h of fermentation. In fermentor testing, it was obvious that the oxygen conditions varied with the H₂O₂ addition time. Eventually, gum yield of 4.2% (w/w) was achieved (increased by 27.3%). Compared with the method of intense mixing and increasing the air flow rate, adding H₂O₂ to improve the dissolved oxygen concentration was more effective and much better. Moreover, addition of H₂O₂ improved the quality of xanthan gum; the pyruvate content of xanthan was 4.4% (w/w), higher than that of the control (3.2%). PMID:22183692

  6. The discrepancy between central foveal thickness and best corrected visual acuity in cystoid macular edema secondary to central retinal vein occlusion after intravitreal lucentis® injection.

    PubMed

    Hua, Rui; Li, Chenyan; Hu, Yuedong; Chen, Lei

    2015-06-01

    Cystoid macular edema is a common retinal disorder with the potential for significant vision-related morbidity, and intravitreal lucentis(®) injection is confirmed to be an effective therapy approach. In the present study, we investigated the discrepancy between central foveal thickness and best corrected visual acuity in such lesions and infered that intravitreal lucentis(®) injection may help the visual function, related to the renewal of cells. PMID:25818575

  7. Visual acuity, self-reported vision and falls in the EPIC-Norfolk Eye study

    PubMed Central

    Yip, Jennifer L Y; Khawaja, Anthony P; Broadway, David; Luben, Robert; Hayat, Shabina; Dalzell, Nichola; Bhaniani, Amit; Wareham, Nicholas; Khaw, Kay-Tee; Foster, Paul J

    2014-01-01

    Purpose To examine the relationship between visual acuity (VA) and self-reported vision (SRV) in relation to falls in 8317 participants of the European Prospective Investigation into Cancer-Norfolk Eye study. Methods All participants completed a health questionnaire that included a question regarding SRV and questions regarding the number of falls in the past year. Distance VA was measured using a logMAR chart for each eye. Poor SRV was defined as those reporting fair or poor distance vision. The relationship between VA and SRV and self-rated falls was analysed by logistic regression, adjusting for age, sex, physical activity, body mass index, chronic disease, medication use and grip strength. Results Of 8317 participants, 26.7% (95% CI 25.7% to 27.7%) had fallen in the past 12 months. Worse VA and poorer SRV were associated with one or more falls in multivariable analysis (OR for falls=1.31, 95% CI 1.04 to 1.66 and OR=1.32, 95% CI 1.09 to 1.61, respectively). Poorer SRV was significantly associated with falls even after adjusting for VA (OR=1.28, 95% CI 1.05 to 1.57). Conclusions SRV was associated with falls independently of VA and could be used as a simple proxy measure for other aspects of visual function to detect people requiring vision-related falls interventions. PMID:24338086

  8. Pediatric Canadian Triage and Acuity Scale (PaedsCTAS) as a Measure of Injury Severity.

    PubMed

    Yates, Morgan Thorn; Ishikawa, Takuro; Schneeberg, Amy; Brussoni, Mariana

    2016-01-01

    This research explored whether the pediatric version of the Canadian Triage Acuity Scale (PaedsCTAS) represented a valid alternative indicator for surveillance of injury severity. Every patient presenting in a Canadian emergency department is assigned a CTAS or PaedsCTAS score in order to prioritize access to care and to predict the nature and scope of care that is likely to be required. The five-level PaedsCTAS score ranges from I (resuscitation) to V (non-urgent). A total of 256 children, 0 to 17-years-old, who attended a pediatric hospital for an injury were followed longitudinally. Of these children, 32.4% (n = 83) were hospitalized and 67.6% (n = 173) were treated in the emergency department and released. They completed the PedsQL(TM), a validated measure of health related quality of life, at baseline (pre-injury status), one-month, four- to six-months, and 12-months post-injury. In this secondary data analysis, PaedsCTAS was found to be significantly associated with hospitalization and length of stay, sensitive to the differences between PaedsCTAS II and III, and related to physical but not psychosocial HRQoL. The findings suggest that PaedsCTAS may be a useful proxy measure of injury severity to supplement or replace hospitalization status and/or length of stay, currently proxy measures. PMID:27399743

  9. Aircrew visual acuity viewing with different night vision goggle eyepiece diopter settings

    NASA Astrophysics Data System (ADS)

    Angel, Share-Dawn P.; Baldwin, J. Bruce

    2004-09-01

    The AN/AVS-9 night vision goggle (NVG) has an eyepiece lens that can be adjusted from +2 to -6 diopters (D). We have shown previously1,2,3 that on average NVG users tend to select about -1D, with a range of +0.5D to -4D3. This study was designed to evaluate NVG visual acuity (NVG VA) and subjective ratings for a range of diopter settings including user-selected and three fixed settings of -0.25D, -1D and -2D. Twenty-one experienced USAF Special Operations aircrew members, including 15 pilots, served as subjects. The median user-selected setting was -1.25D and ranged from +0.5D to -3.5D. Only 2 of the 21 subjects had user-selected NVG VA significantly better than a fixed setting of -1D. Of those two, one was not wearing prescribed glasses and the other was 49 years old, presbyopic, and could not focus through the -1D lenses. Subjective ratings and NVG VA indicated that most people could fly with a fixed setting of -1D for each eye, although two individuals needed different diopter settings for the right and left eyes. The new Panoramic NVG (PNVG) has a fixed eyepiece focus of -1D. Results suggest the PNVG should have a limited set of accessory lenses available.

  10. Serum lipid fatty acids and temporal processing acuity in children with oral clefts.

    PubMed

    Laasonen, M; Erkkilä, A T; Isotalo, E; Mäenpää, P K; Pulkkinen, J J; Virsu, V; Haapanen, M-L

    2006-04-01

    We investigated the relation between a biological factor (fatty acids, FA) and a cognitive processing speed factor (temporal processing acuity, TPA) that are both suggested to relate to neuronal and cognitive functioning. Blood samples of 49 ten-year-old children with oral clefts were collected for FA analysis in serum triglycerides, cholesteryl esters, and phospholipids on the same day as they performed behavioral TPA tasks (simultaneity/nonsimultaneity judgments) in several perceptual modalities (visual, auditory, tactile, audiotactile, visuotactile, and audiovisual). This population has larger than expected variation in the relevant cognitive measures (TPA, learning ability, and intelligence). Sequential regression analyses (adjusted for age, gender, and cleft type) showed that saturated FAs were not generally associated with TPA. Monounsaturated erucic and nervonic acids were inversely related with TPA. Of the polyunsaturated fatty acids, eicosapentaenoic and docosahexaenoic acids were positively associated with TPA, whereas gamma-linolenic acid was inversely related to TPA. In summary, we found significant relations between a biological (certain FAs) and a cognitive factor (TPA). PMID:16545557

  11. Pediatric Canadian Triage and Acuity Scale (PaedsCTAS) as a Measure of Injury Severity

    PubMed Central

    Yates, Morgan Thorn; Ishikawa, Takuro; Schneeberg, Amy; Brussoni, Mariana

    2016-01-01

    This research explored whether the pediatric version of the Canadian Triage Acuity Scale (PaedsCTAS) represented a valid alternative indicator for surveillance of injury severity. Every patient presenting in a Canadian emergency department is assigned a CTAS or PaedsCTAS score in order to prioritize access to care and to predict the nature and scope of care that is likely to be required. The five-level PaedsCTAS score ranges from I (resuscitation) to V (non-urgent). A total of 256 children, 0 to 17-years-old, who attended a pediatric hospital for an injury were followed longitudinally. Of these children, 32.4% (n = 83) were hospitalized and 67.6% (n = 173) were treated in the emergency department and released. They completed the PedsQLTM, a validated measure of health related quality of life, at baseline (pre-injury status), one-month, four- to six-months, and 12-months post-injury. In this secondary data analysis, PaedsCTAS was found to be significantly associated with hospitalization and length of stay, sensitive to the differences between PaedsCTAS II and III, and related to physical but not psychosocial HRQoL. The findings suggest that PaedsCTAS may be a useful proxy measure of injury severity to supplement or replace hospitalization status and/or length of stay, currently proxy measures. PMID:27399743

  12. The Flex Track: Flexible Partitioning between Low- and High-Acuity Areas of an Emergency Department

    PubMed Central

    Laker, Lauren F.; Froehle, Craig M.; Lindsell, Christopher J.; Ward, Michael J.

    2014-01-01

    Study Objective EDs with both low- and high-acuity treatment areas often have fixed allocation of resources, regardless of demand. We demonstrate the utility of discrete-event simulation to evaluate flexible partitioning between low- and high-acuity ED areas to identify the best operational strategy for subsequent implementation. Methods A discrete-event simulation was used to model patient flow through a 50-bed, urban, teaching ED that handles 85,000 patient visits annually. The ED has historically allocated ten beds to a Fast Track for low-acuity patients. We estimated the effect of a Flex Track policy, which involved switching up to five of these Fast Track beds to serving both low- and high-acuity patients, on patient waiting times. When the high-acuity beds were not at capacity, low-acuity patients were given priority access to flexible beds. Otherwise, high-acuity patients were given priority access to flexible beds. Wait times were estimated for patients by disposition and emergency severity index (ESI) score. Results A Flex Track policy using three flexible beds produced the lowest mean patient waiting of 30.9 (95% CI 30.6–31.2) minutes. The typical Fast Track approach of rigidly separating high- and low–acuity beds produced a mean patient wait time of 40.6 (95% CI 40.2–50.0) minutes, 31% higher than the three-bed Flex Track. A completely flexible ED, where all beds can accommodate any patient, produced mean wait times of 35.1 (95% CI 34.8–35.4) minutes. The results from the three-bed Flex Track scenario were robust, performing well across a range of scenarios involving higher and lower patient volumes and care durations. Conclusion Using discrete-event simulation, we have shown that adding some flexibility into bed allocation between low- and high-acuity can provide substantial reductions in overall patient waiting and a more efficient ED. PMID:24954578

  13. A randomized controlled trial of early kangaroo care for preterm infants: effects on temperature, weight, behavior, and acuity.

    PubMed

    Chwo, Miao-Ju; Anderson, Gene C; Good, Marion; Dowling, Donna A; Shiau, Shiow-Hwa H; Chu, Der-Ming

    2002-06-01

    Kangaroo care (KC) has been the intervention for preterm infants in numerous published studies. However, most well designed studies to date have used a one-group repeated measure design. This methodology is not as definitive as an experimental design. Because of the absence of a comparable control group, change between pretest and posttest may be due to any other environmental variables or normal variation of subjects (Kirk, 1995). This randomized controlled trial (RCT) was done to test the hypotheses that KC infants would have higher mean tympanic temperatures, less weight loss, more optimal behavioral states, and lower acuity (length of stay). Thirty-four eligible mother-infant dyads were randomly assigned to the KC or the control group by computerized minimization on the day following birth. Stratification variables included infant gender, birth weight, delivery method, and parity. KC infants compared to control infants had higher mean tympanic temperature (37.3 degrees C vs. 37.0 degrees C), more quiet sleep (62% vs. 22%), and less crying (2% vs. 6%) all at p=.000. No significant difference was found for weight loss and acuity (length of stay). These findings can be used for evidence-based nursing practice in Taiwan. With the knowledge attained from this RCT, nurses can educate and motivate mothers to keep their stable preterm infants warm by skin-to- skin contact inside their clothing, thereby encouraging self-regulatory feeding. PMID:12119598

  14. Vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception

    PubMed Central

    Yang, Shan-Shan; Jiang, Tao

    2013-01-01

    AIM To evaluate the efficacy of surgical treatment of vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception (NLP). METHODS This was a retrospective uncontrolled interventional case-series of 19 patients of severely traumatized eyes with NLP who underwent vitrectomy surgery at the Affiliated Hospital of Medical College, Qingdao University (Qingdao, China) during a 3-year period. We recorded perioperative factors with the potential to influence functional outcome including duration from the injury to intervention; causes for ocular trauma; open globe or closed globe injury; grade of vitreous hemorrhage; grade of endophthalmitis; grade of retinal detachment; size and location of intraocular foreign body (IOFB); extent and position of retinal defect; grade of proliferative vitreoretinopathy (PVR); type of surgery; perioperative complications and tamponade agent. The follow-up time was from 3 to 18 months, and the mean time was 12 months. RESULTS After a mean follow-up period of 12 months (3-18 months) 10.53% (2/19) of eyes had visual acuity of between 20/60 and 20/400, 52.63% (10/19) had visual acuity less than 20/400 but more than NLP, and 36.84% (7/19) remained NLP. Visual acuity was improved from NLP to light perception (LP) or better in 63.16% (12/19) of eyes and the rate of complete retinal reattachment was 73.68% (14/19). Good visual acuity all resulted from those patients of blunt trauma with intact eyewall (closed globe injury). The perioperative factors of poor visual acuity prognosis included delayed intervention; open globe injury; endophthalmitis; severe retinal detachment; large IOFB; macular defect; a wide range of retinal defects and severe PVR. CONCLUSION The main reasons of NLP after ocular trauma are severe vitreous hemorrhage opacity; refractive media opacity; retinal detachment; retinal and uveal damages and defects, especially defects of the macula; PVR and

  15. Dynamic Visual Acuity and Landing Sickness in Crewmembers Returning from Long-Duration Spaceflight

    NASA Technical Reports Server (NTRS)

    Rosenberg, M. J. F.; Peters, B. T.; Reschke, M. F.

    2016-01-01

    Long-term exposure to microgravity causes sensorimotor adaptations that result in functional deficits upon returning to a gravitational environment. At landing the vestibular system and the central nervous system, responsible for coordinating head and eye movements, are adapted to microgravity and must re-adapt to the gravitational environment. This re-adaptation causes decrements in gaze control and dynamic visual acuity, with astronauts reporting oscillopsia and blurred vision. Dynamic visual acuity (DVA) is assessed using an oscillating chair (Figure 1) developed in the Neuroscience Laboratory at JSC. This chair is lightweight and easily portable for quick deployment in the field. The base of the chair is spring-loaded and allows for manual oscillation of the subject. Using a metronome, the chair is vertically oscillated +/- 2 cm at 2 Hz by an operator, to simulate walking. While the subject is being oscillated, they are asked to discern the direction of Landolt-C optotypes of varying sizes presented on a screen 1 m from the subject and record their direction using a gamepad. The visual acuity thresholds are determined using an algorithm that alters the size of the optotype based on the previous responses of the subject using a forced-choice best parameter estimation that is able to rapidly converge on the threshold value. Visual acuity thresholds are determined both for static (seated) and dynamic (oscillating) conditions. Dynamic visual acuity is defined as the difference between the dynamic and static conditions.

  16. Robot-Aided Mapping of Wrist Proprioceptive Acuity across a 3D Workspace.

    PubMed

    Marini, Francesca; Squeri, Valentina; Morasso, Pietro; Konczak, Jürgen; Masia, Lorenzo

    2016-01-01

    Proprioceptive signals from peripheral mechanoreceptors form the basis for bodily perception and are known to be essential for motor control. However we still have an incomplete understanding of how proprioception differs between joints, whether it differs among the various degrees-of-freedom (DoFs) within a particular joint, and how such differences affect motor control and learning. We here introduce a robot-aided method to objectively measure proprioceptive function: specifically, we systematically mapped wrist proprioceptive acuity across the three DoFs of the wrist/hand complex with the aim to characterize the wrist position sense. Thirty healthy young adults performed an ipsilateral active joint position matching task with their dominant wrist using a haptic robotic exoskeleton. Our results indicate that the active wrist position sense acuity is anisotropic across the joint, with the abduction/adduction DoF having the highest acuity (the error of acuity for flexion/extension is 4.64 ± 0.24°; abduction/adduction: 3.68 ± 0.32°; supination/pronation: 5.15 ± 0.37°) and they also revealed that proprioceptive acuity decreases for smaller joint displacements. We believe this knowledge is imperative in a clinical scenario when assessing proprioceptive deficits and for understanding how such sensory deficits relate to observable motor impairments. PMID:27536882

  17. Robot-Aided Mapping of Wrist Proprioceptive Acuity across a 3D Workspace

    PubMed Central

    Marini, Francesca; Squeri, Valentina; Morasso, Pietro; Konczak, Jürgen; Masia, Lorenzo

    2016-01-01

    Proprioceptive signals from peripheral mechanoreceptors form the basis for bodily perception and are known to be essential for motor control. However we still have an incomplete understanding of how proprioception differs between joints, whether it differs among the various degrees-of-freedom (DoFs) within a particular joint, and how such differences affect motor control and learning. We here introduce a robot-aided method to objectively measure proprioceptive function: specifically, we systematically mapped wrist proprioceptive acuity across the three DoFs of the wrist/hand complex with the aim to characterize the wrist position sense. Thirty healthy young adults performed an ipsilateral active joint position matching task with their dominant wrist using a haptic robotic exoskeleton. Our results indicate that the active wrist position sense acuity is anisotropic across the joint, with the abduction/adduction DoF having the highest acuity (the error of acuity for flexion/extension is 4.64 ± 0.24°; abduction/adduction: 3.68 ± 0.32°; supination/pronation: 5.15 ± 0.37°) and they also revealed that proprioceptive acuity decreases for smaller joint displacements. We believe this knowledge is imperative in a clinical scenario when assessing proprioceptive deficits and for understanding how such sensory deficits relate to observable motor impairments. PMID:27536882

  18. Experience Modifies Olfactory Acuity: Acetylcholine-Dependent Learning Decreases Behavioral Generalization between Similar Odorants

    PubMed Central

    Fletcher, Max L.; Wilson, Donald A.

    2008-01-01

    Perceptual learning has been demonstrated in several thalamocortical sensory systems wherein experience enhances sensory acuity for trained stimuli. This perceptual learning is believed to be dependent on changes in sensory cortical receptive fields. Sensory experience and learning also modifies receptive fields and neural response patterns in the mammalian olfactory system; however, to date there has been little reported evidence of learned changes in behavioral olfactory acuity. The present report used a bradycardial orienting response and cross-habituation paradigm that allowed assessment of behavioral discrimination of nearly novel odorants, and then used the same paradigm to examine odorant discrimination after associative olfactory conditioning with similar or dissimilar odorants. The results demonstrate that associative conditioning can enhance olfactory acuity for odors that are the same as or similar to the learned odorant, but not for odors dissimilar to the learned odorant. Furthermore, scopolamine injected before associative conditioning can block the acquisition of this learned enhancement in olfactory acuity. These results could have important implications for mechanisms of olfactory perception and memory, as well as for correlating behavioral olfactory acuity with observed spatial representations of odorant features in the olfactory system. PMID:11784813

  19. Significant Improvement in Sleep in People with Intellectual Disabilities Living in Residential Settings by Non-Pharmaceutical Interventions

    ERIC Educational Resources Information Center

    Hylkema, T.; Vlaskamp, C.

    2009-01-01

    Background: Although about 15 to 50 percent of people with intellectual disabilities (ID) living in residential settings suffer from sleep problems, scant attention is paid to these problems. Most available studies focus on pharmaceutical solutions. In this study we focus on improving sleep in people with intellectual disabilities living in…

  20. Brief Communication: Upper-air relaxation in RACMO2 significantly improves modelled interannual surface mass balance variability in Antarctica

    NASA Astrophysics Data System (ADS)

    van de Berg, Willem Jan; Medley, Brooke

    2016-03-01

    The Regional Atmospheric Climate Model (RACMO2) has been a powerful tool for improving surface mass balance (SMB) estimates from GCMs or reanalyses. However, new yearly SMB observations for West Antarctica show that the modelled interannual variability in SMB is poorly simulated by RACMO2, in contrast to ERA-Interim, which resolves this variability well. In an attempt to remedy RACMO2 performance, we included additional upper-air relaxation (UAR) in RACMO2. With UAR, the correlation to observations is similar for RACMO2 and ERA-Interim. The spatial SMB patterns and ice-sheet-integrated SMB modelled using UAR remain very similar to the estimates of RACMO2 without UAR. We only observe an upstream smoothing of precipitation in regions with very steep topography like the Antarctic Peninsula. We conclude that UAR is a useful improvement for regional climate model simulations, although results in regions with steep topography should be treated with care.

  1. Comparison of salty taste acuity and salty taste preference with sodium intake and blood pressure based on zinc nutritional status in two rural populations in Korea.

    PubMed

    Choe, Jeong-Sook; Kim, Eun-Kyung; Kim, Eun-Kyung

    2012-12-01

    This study examined salty taste acuity and salty taste preference and sodium intake in relation to zinc nutritional status in 2 rural populations in Korea. And we also examined the main food contributors of their sodium intakes. We enrolled 218 adults (66 men and 152 women) from the Kangneung and Samcheok regions in Korea's Kangwon province in our study conducted from December 2011 to February 2012. Participants from each region were divided into 3 groups based on their serum zinc level (T1: lowest, T2: intermediate, T3: highest). We compared the salty taste acuity and preference, Na index (Dish Frequency Questionnaire for estimation of habitual sodium intake), blood pressure, and intakes of nutrients including sodium by 3 groups of serum zinc level. The results were as follows: a higher serum zinc level indicated a lower sodium intake and Na index (P < 0.05). The salty taste acuity was considerably higher for participants from the Kangneung region than those from the Samcheok region (P < 0.05). And the serum zinc level was significantly higher in participants from the Kangneung region than those from the Samcheok region (P < 0.05). We further divided the participants into 2 groups: those who consumed more zinc than the recommended intake (RI) and the others. We compared salty taste acuity and salty taste preference in the 2 groups. The salty taste threshold and palatable salty taste concentrations were lower for the group with a zinc intake above RI than for the group with zinc intake below the RI. However, the difference was not significant. This study confirms that taste function differs depending on zinc nutritional status. In future, it is required to a large-scale, long-term, prospective study on the correlation between zinc intake, serum zinc levels, and taste perception function and blood pressure. PMID:23346304

  2. Highly Asymmetric n(+) -p Heterojunction Quantum-Dot Solar Cells with Significantly Improved Charge-Collection Efficiencies.

    PubMed

    Choi, Min-Jae; Kim, Sunchuel; Lim, Hunhee; Choi, Jaesuk; Sim, Dong Min; Yim, Soonmin; Ahn, Byung Tae; Kim, Jin Young; Jung, Yeon Sik

    2016-03-01

    The depletion region width of metal-oxide/quantum-dot (QD) heterojunction solar cells is increased by a new method in which heavily boron-doped n(+) -ZnO is employed. It is effectively increased in the QD layer by 30% compared to the counterpart with conventional n-ZnO, and provides 41% and 37% improvement of Jsc (16.7 mA cm(-2) to 23.5 mA cm(-2) ) and power conversion efficiency (5.52% to 7.55%), respectively. PMID:26689133

  3. Posterior staphyloma in oculocutaneous albinism: another possible cause of reduced visual acuity

    PubMed Central

    Lee, Susan; Schimmenti, Lisa A.; King, Richard A.; Brilliant, Murray; Anderson, Jennifer L.; Schoonveld, Cheri; Summers, C. Gail

    2016-01-01

    Posterior staphyloma is typically associated with myopic degeneration and has not been recognized as a cause of reduced visual acuity in albinism. We report 3 cases of posterior staphyloma, each with oculocutaneous albinism (OCA) defined by phenotype and genotype. Two cases are biological sisters with OCA type 2; one was myopic and the other was hyperopic. The third case involves a man with OCA associated with Hermansky-Pudlak syndrome (HPS-5). Staphyloma may be another cause of reduced visual acuity in albinism, particularly with increasing age. It may occur in association with myopia or hyperopia. PMID:26691042

  4. Posterior staphyloma in oculocutaneous albinism: another possible cause of reduced visual acuity.

    PubMed

    Lee, Susan; Schimmenti, Lisa A; King, Richard A; Brilliant, Murray; Anderson, Jennifer L; Schoonveld, Cheri; Summers, C Gail

    2015-12-01

    Posterior staphyloma is typically associated with myopic degeneration and has not been recognized as a cause of reduced visual acuity in albinism. We report 3 cases of posterior staphyloma, each with oculocutaneous albinism (OCA) defined by phenotype and genotype. Two cases are biological sisters with OCA type 2; one was myopic and the other was hyperopic. The third case involves a man with OCA associated with Hermansky-Pudlak syndrome (HPS-5). Staphyloma may be another cause of reduced visual acuity in albinism, particularly with increasing age. It may occur in association with myopia or hyperopia. PMID:26691042

  5. [Significance of intermittent CDDP therapy for improving long-term prognosis in patients with advanced ovarian cancer].

    PubMed

    Umesaki, N; Yamamoto, A; Nakano, M; Matsumoto, Y; Tsuda, K; Kawabata, M; Sugawa, T

    1991-12-01

    In cases of advanced ovarian cancer, intermittent CDDP therapy (ICDDPT) was applied after the first operation and induction chemotherapy, and its efficacy and limit were studied. One cycle of this therapy involved consecutive 5 day CDDP treatment (25-30mg/body/day). The therapy was repeated at intervals of 3 months. In many cases, ovarian cancer was histologically rated as epithelial adenocarcinoma. The study included 18 cases in total. ICDDPT was applied to 13 cases in which no tumor mass was detected by second look operation (SLO) or which showed clinical remission after operation. Only 3 of these 13 cases showed recurrence, and all these 13 are still living. Of the 5 cases in which SLO disclosed a tumor mass or which did not show remission after the first operation, 2 died. When the survival rate after ICDDPT was compared by the Kaplan-Meier method with that of controls without CDDP therapy, the effectiveness of ICDDPT was demonstrated. The survival rate could therefore be improved by ICDDPT. The therapy particularly improved the long term prognosis of SLO negative cases and cases in clinical remission. It seems necessary to repeat this therapy for a long period to achieve satisfactory results. In SLO positive cases and cases without clinical remission, the therapy had only a limited effect. PMID:1744459

  6. [A case of orbital apex syndrome due to aspergillus infection that avoided loss of visual acuity by optic canal decompression].

    PubMed

    Yoshida, Kenji; Shirata, Akiko; Sato, Taku; Kishida, Yugo; Saito, Kiyoshi; Yamane, Kiyomi

    2016-01-01

    A 71-year-old woman was admitted to our hospital complaining of left orbital pain, headache, diplopia and left-sided ptosis, which she had suffered for two months. On examination, the patient had loss of visual acuity, left-sided ptosis, lateral gaze disturbance, and was diagnosed as having left orbital apex syndrome. An abnormal signal to the left orbital cone was detected on MRI. Serum β-D-glucan was increased, and serum Aspergillus antigen and antibody were both positive. Although antifungal drugs (voriconazole and liposomal amphotericin B) were administered, the symptoms deteriorated. The patient then underwent optic nerve decompression surgery and was treated with intravenous methylprednisolone, which gradually improved the patient's symptoms, Aspergillus hyphae were confirmed by pathological examination. To obtain good prognosis for patients with orbital apex syndrome associated with Aspergillus infection, optic nerve decompression surgery should be considered. PMID:26616482

  7. Association between ambient noise exposure, hearing acuity, and risk of acute occupational injury

    PubMed Central

    Cantley, Linda F; Galusha, Deron; Cullen, Mark R; Dixon-Ernst, Christine; Rabinowitz, Peter M; Neitzel, Richard L

    2015-01-01

    Objective This study aimed to examine the associations between acute workplace injury risk, ambient noise exposure, and hearing acuity, adjusting for reported hearing protection use. Methods In a cohort of 9220 aluminum manufacturing workers studied over six years (33 300 person-years, 13 323 person-jobs), multivariate mixed effects models were used to estimate relative risk (RR) of all injuries as well as serious injuries by noise exposure category and hearing threshold level (HTL) adjusting for recognized and potential confounders. Results Compared to noise <82 dBA, higher exposure was associated with elevated risk in a monotonic and statistically significant exposure–response pattern for all injuries and serious injuries with higher risk estimates observed for serious injuries [82–84.99 dBA: RR 1.26, 95% confidence interval (95% CI) 0.96–1.64; 85–87.99 dBA: RR 1.39, 95% CI 1.05–1.85; ≥88 dBA: RR 2.29, 95% CI 1.52–3.47]. Hearing loss was associated with increased risk for all injuries, but was not a significant predictor of risk for the subset of more serious injuries. Compared to those without hearing loss, workers with HTL ≥25 dB had 21% increased all injury risk (RR 1.21, 95% CI 1.09–1.33) while those with HTL 10–24.99 dB had 6% increased risk (RR 1.06, 95% CI 1.00–1.13). Reported hearing protection type did not predict injury risk. Conclusion Noise exposure levels as low as 85 dBA may increase workplace injury risk. HTL was associated with increased risk for all, but not the subset of serious, injuries. Additional study is needed both to confirm the observed associations and explore causal pathways. PMID:25137556

  8. Importance of Central Retinal Sensitivity for Prediction of Visual Acuity after Intravitreal Bevacizumb in Eyes with Macular Edema Associated with Branch Retinal Vein Occlusion

    PubMed Central

    Sugimoto, Masahiko; Ichio, Atsushi; Kondo, Mineo

    2016-01-01

    Objective To determine whether the baseline retinal sensitivity can predict the best-corrected visual acuity (BCVA) at 1 month after intravitreal bevacizumab (IVB) in eyes with macular edema (ME) associated with a branch retinal vein occlusion (BRVO). Subjects and Methods We evaluated 16 eyes of 16 patients who had ME associated with a BRVO. The mean ± standard deviation age was 69.1 ± 8.9 years, and all had a single IVB injection. The BCVA, central macular thickness (CMT), integrity of the ellipsoid zone (EZ) of the photoreceptors, and retinal sensitivity were determined before (baseline) and at 1 day, 1 week, and 1 month following the IVB. The average threshold retinal sensitivity (AT) within the central 10° was determined by Macular Integrity Assessment. The correlations between the BCVA at 1 month and the CMT, integrity of the EZ, and AT at each visit were determined. Results One month after IVB, the BCVA improved significantly from 0.56 ± 0.27 logMAR units to 0.32 ± 0.28 logMAR units, and the CMT from 611.4 ± 209.3 μm to 258.7 ± 64.0 μm (P <0.05). The AT improved significantly from 17.9 ± 5.3 dB to 21.2 ± 5.0 dB (P <0.05). At 1 day after the treatment, both the integrity of the EZ (r = 0.59) and the retinal sensitivity (r = 0.76) were moderately correlated with the BCVA at 1 month. Conclusion These results indicate that both the integrity of the EZ and the AT at 1 day after the IVB can predict the BCVA after treatment for ME associated with BRVO. There is a possibility that these parameters will predict the effectiveness of IVB for each case. PMID:26885822

  9. Environmental Assessment and Finding of No Significant Impact: Proposed Improvements at the Thomas Jefferson National Accelerator Facility Newport News, Virginia

    SciTech Connect

    N /A

    2002-07-13

    The U. S. Department of Energy (DOE), in this Environmental Assessment (EA), reports the results of an analysis of the potential environmental impacts from the proposed construction of various site improvements and the proposed installation and operation of the Helios light source at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia. Jefferson Lab is operated by the Southeastern Universities Research Association, Inc. (SURA) under contract to DOE. With this proposal, DOE intends to construct no more than four major two or three story additions totaling about 151,000 sq. ft. (square feet) to CEBAF Center, the main facility administration building, and the addition of three new single story and one two story operations support structures on the accelerator site. The structures are a 28,000 sq. ft. storage building, a 15,100 sq. ft. technical support building, a 3,500 sq. ft. refrigeration service building, and a two-story 22,600 sq. ft addition to the Free Electron Laser (FEL) facility. The proposed action also involves the installation and operation of the Helios (High-Energy Lithography Source) accelerator in the FEL Addition. DOE proposes to take this action to provide Jefferson Lab with improved staff and operations support facilities that, along with the operation of Helios, will provide an increased capability to facilitate accelerator and physics program operations. Support activities necessary to effect the installation and operation of Helios would begin in Fiscal Year (FY) 03. It is expected that the Helios machine should be available to serve developmental and operational activities in support of the physics program later in FY 04. In this EA, DOE presents the no action alternative, alternatives considered and dismissed, and the proposed action alternative. It also evaluates the impacts of each.

  10. Optical Coherence Tomography and Visual Acuity: Photoreceptor Loss

    NASA Astrophysics Data System (ADS)

    Salam, Adzura; Wolf-Schnurrbusch, Ute Ellen Kathrin; Wolf, Sebastian

    SD-OCT has improved the visualization of intraretinal morphologic features quantitatively and qualitatively. SD-OCT allows the retinal physician to evaluate the integrity of each retinal layer such as the external limiting membrane (ELM) and the junction between the inner and outer segments (IS/OS junction) of the photoreceptors The presence and integrity of the external limiting membrane (ELM), the photoreceptor inner segment(IS), the outer segment(OS), and the retinal pigment epithelium (RPE) appears to be a good prognostic feature for visual improvement after treatment for various macular diseases.

  11. The effect of exposure duration on visual acuity for letter optotypes and gratings

    PubMed Central

    McAnany, J. Jason

    2014-01-01

    This study compared the effects of exposure duration on letter and grating targets in a visual acuity (VA) task and determined if the broadband nature of letters accounts for their temporal summation characteristics. Log MAR (minimum angle of resolution) VA of five individuals (ages 25 to 36) was measured with a set of tumbling E optotypes for durations of 24 ms to 1 s. The Es were either unfiltered or low-pass filtered to determine the object frequencies (cycles per letter; cplE) mediating VA. The retinal frequencies mediating VA for the unfiltered E (cycles per degree; cpdE) were derived from the ratio of cplE to MAR. Values of cpdE were compared to threshold retinal frequency obtained with band-limited Es and gratings to further evaluate the effects of stimulus bandwidth. Both log MAR and log cplE for the unfiltered E decreased as duration increased up to approximately 260 ms, and were constant thereafter. VA also improved for gratings and band-pass filtered Es, but over a shorter time course (approximately 150 ms). The effect of duration on VA for the broadband E, Gabor, and band-pass filtered E was similar when the object frequencies mediating VA were included in the definition of VA by converting to cpdE. The results indicate that the pattern of temporal integration for the tumbling E is related to its broadband nature. Band-pass filtered letters can simplify the interpretation of VA because the object frequency information mediating VA is known exactly and is independent of duration and letter size. PMID:25281413

  12. MicroRNA-145 Inhibitor Significantly Improves the Development of Bovine Somatic Cell Nuclear Transfer Embryos In Vitro.

    PubMed

    Li, Wenzhe; Xiong, Yongjie; Wang, Fengyu; Liu, Xin; Gao, Yang; Wang, Yongsheng; Zhang, Yong; Jin, Yaping

    2016-08-01

    Directly regulating the translation of POU5F1, SOX2, KLF4, and miRNA-145 plays an important role in maintaining the pluripotency of stem cells and the development of early embryos. In the present study, the expression model of miRNA-145 on bovine somatic cell nuclear transfer (SCNT) and in vitro fertilized (IVF) embryos were investigated and compared. Results indicated that (1) the expression level of miRNA-145 was significantly higher in SCNT embryos than that in IVF embryos after the eight-cell stage; (2) miRNA-145 negatively regulated the POU5F1, SOX2, and KLF4 in bovine embryos; (3) decreasing the expression of miRNA-145 by the miRNA-145 inhibitor significantly enhanced the expression of these three genes and the blastocyst formation rate; it also increased the total cell number and inner cell mass ratio of the bovine day 7 SCNT embryos. In conclusion, decreasing miRNA-145 expression might be a feasible means to enhance SCNT efficiency in bovines. PMID:27459582

  13. Creation of an Accurate Algorithm to Detect Snellen Best Documented Visual Acuity from Ophthalmology Electronic Health Record Notes

    PubMed Central

    French, Dustin D; Gill, Manjot; Mitchell, Christopher; Jackson, Kathryn; Kho, Abel; Bryar, Paul J

    2016-01-01

    Background Visual acuity is the primary measure used in ophthalmology to determine how well a patient can see. Visual acuity for a single eye may be recorded in multiple ways for a single patient visit (eg, Snellen vs. Jäger units vs. font print size), and be recorded for either distance or near vision. Capturing the best documented visual acuity (BDVA) of each eye in an individual patient visit is an important step for making electronic ophthalmology clinical notes useful in research. Objective Currently, there is limited methodology for capturing BDVA in an efficient and accurate manner from electronic health record (EHR) notes. We developed an algorithm to detect BDVA for right and left eyes from defined fields within electronic ophthalmology clinical notes. Methods We designed an algorithm to detect the BDVA from defined fields within 295,218 ophthalmology clinical notes with visual acuity data present. About 5668 unique responses were identified and an algorithm was developed to map all of the unique responses to a structured list of Snellen visual acuities. Results Visual acuity was captured from a total of 295,218 ophthalmology clinical notes during the study dates. The algorithm identified all visual acuities in the defined visual acuity section for each eye and returned a single BDVA for each eye. A clinician chart review of 100 random patient notes showed a 99% accuracy detecting BDVA from these records and 1% observed error. Conclusions Our algorithm successfully captures best documented Snellen distance visual acuity from ophthalmology clinical notes and transforms a variety of inputs into a structured Snellen equivalent list. Our work, to the best of our knowledge, represents the first attempt at capturing visual acuity accurately from large numbers of electronic ophthalmology notes. Use of this algorithm can benefit research groups interested in assessing visual acuity for patient centered outcome. All codes used for this study are currently

  14. Significantly improving stellar mass and radius estimates: a new reference function for the Δν scaling relation

    NASA Astrophysics Data System (ADS)

    Guggenberger, Elisabeth; Hekker, Saskia; Basu, Sarbani; Bellinger, Earl

    2016-08-01

    The scaling relations between global asteroseismic observables and stellar properties are widely used to estimate masses and radii of stars exhibiting solar-like oscillations. Since the mass and radius of the Sun are known independently, the Sun is commonly used as a reference to scale to. However, the validity of the scaling relations depends on the homology between the star under study and the reference star. Solar-like oscillators span a wide range of masses and metallicities, as well as evolutionary phases. Most of these stars are therefore not homologous to the Sun. This leads to errors of up to 10% (5%) in mass (radius) when using the asteroseismic scaling relations with the Sun as the reference. In this paper we derive a reference function to replace the solar-reference value used in the large-frequency-separation scaling relation. Our function is the first that depends on both effective temperature and metallicity, and is applicable from the end of the main sequence to just above the bump on the red giant branch. This reference function improves the estimates of masses and radii determined through scaling relations by a factor of 2, i.e. allows masses and radii to be recovered with an accuracy of 5% and 2%, respectively.

  15. Improving winter leaf area index estimation in coniferous forests and its significance in estimating the land surface albedo

    NASA Astrophysics Data System (ADS)

    Wang, Rong; Chen, Jing M.; Pavlic, Goran; Arain, Altaf

    2016-09-01

    Winter leaf area index (LAI) of evergreen coniferous forests exerts strong control on the interception of snow, snowmelt and energy balance. Simulation of winter LAI and associated winter processes in land surface models is challenging. Retrieving winter LAI from remote sensing data is difficult due to cloud contamination, poor illumination, lower solar elevation and higher radiation reflection by snow background. Underestimated winter LAI in evergreen coniferous forests is one of the major issues limiting the application of current remote sensing LAI products. It has not been fully addressed in past studies in the literature. In this study, we used needle lifespan to correct winter LAI in a remote sensing product developed by the University of Toronto. For the validation purpose, the corrected winter LAI was then used to calculate land surface albedo at five FLUXNET coniferous forests in Canada. The RMSE and bias values for estimated albedo were 0.05 and 0.011, respectively, for all sites. The albedo map over coniferous forests across Canada produced with corrected winter LAI showed much better agreement with the GLASS (Global LAnd Surface Satellites) albedo product than the one produced with uncorrected winter LAI. The results revealed that the corrected winter LAI yielded much greater accuracy in simulating land surface albedo, making the new LAI product an improvement over the original one. Our study will help to increase the usability of remote sensing LAI products in land surface energy budget modeling.

  16. Significantly improving stellar mass and radius estimates: a new reference function for the Δν scaling relation

    NASA Astrophysics Data System (ADS)

    Guggenberger, Elisabeth; Hekker, Saskia; Basu, Sarbani; Bellinger, Earl

    2016-08-01

    The scaling relations between global asteroseismic observables and stellar properties are widely used to estimate masses and radii of stars exhibiting solar-like oscillations. Since the mass and radius of the Sun are known independently, the Sun is commonly used as a reference to scale to. However, the validity of the scaling relations depends on the homology between the star under study and the reference star. Solar-like oscillators span a wide range of masses and metallicities, as well as evolutionary phases. Most of these stars are therefore not homologous to the Sun. This leads to errors of up to 10 per cent (5 per cent) in mass (radius) when using the asteroseismic scaling relations with the Sun as the reference. In this paper, we derive a reference function to replace the solar-reference value used in the large-frequency separation scaling relation. Our function is the first that depends on both effective temperature and metallicity, and is applicable from the end of the main sequence to just above the bump on the red giant branch. This reference function improves the estimates of masses and radii determined through scaling relations by a factor of 2, i.e. allows masses and radii to be recovered with an accuracy of 5 per cent and 2 per cent, respectively.

  17. Significantly improving stellar mass and radius estimates: A new reference function for the Δν scaling relation

    NASA Astrophysics Data System (ADS)

    Guggenberger, Elisabeth; Hekker, Saskia; Basu, Sarbani; Bellinger, Earl

    2016-06-01

    The scaling relations between global asteroseismic observables and stellar properties are widely used to estimate masses and radii of stars exhibiting solar-like oscillations. Since the mass and radius of the Sun are known independently, the Sun is commonly used as a reference to scale to. However, the validity of the scaling relations depends on the homology between the star under study and the reference star. Solar-like oscillators span a wide range of masses and metallicities, as well as evolutionary phases. Most of these stars are therefore not homologous to the Sun. This leads to errors of up to 10% (5%) in mass (radius) when using the asteroseismic scaling relations with the Sun as the reference. In this paper we derive a reference function to replace the solar-reference value used in the large-frequency-separation scaling relation. Our function is the first that depends on both effective temperature and metallicity, and is applicable from the end of the main sequence to just above the bump on the red giant branch. This reference function improves the estimates of masses and radii determined through scaling relations by a factor of 2, i.e. allows masses and radii to be recovered with an accuracy of 5% and 2%, respectively.

  18. Systematic chemical modifications of single stranded siRNAs significantly improved CTNNB1 mRNA silencing.

    PubMed

    Chang, Wonsuk; Pei, Yi; Guidry, Erin N; Zewge, Daniel; Parish, Craig A; Sherer, Edward C; DiMuzio, Jillian; Zhang, Hangchun; South, Victoria J; Strapps, Walter R; Sepp-Lorenzino, Laura; Colletti, Steven L; Stanton, Matthew G

    2016-09-15

    Single-stranded silencing RNAs (ss siRNA), while not as potent as duplex RNAs, have the potential to become a novel platform technology in RNA interference based gene silencing by virtue of their simplicity and plausibly favorable characteristics in pharmacokinetics and biodistribution. Like other therapeutic pharmaceutical agents, ss siRNA can be optimized to achieve higher potency through a structure-activity based approach. Systematic chemical modification at each position of a 21-mer oligonucleotide identified 2',5'-linked 3'-deoxythymidine (3dT) at position 1 and locked nucleic acids (LNAs) at the seed region as key components to afford significant enhancement in knockdown activity both in vitro and in vivo. Further optimization by additional chemical modifications should enable ss siRNA as an alternative gene silencing modality. PMID:27503684

  19. Dimension Reduction via Unsupervised Learning Yields Significant Computational Improvements for Support Vector Machine Based Protein Family Classification.

    SciTech Connect

    Webb-Robertson, Bobbie-Jo M.; Matzke, Melissa M.; Oehmen, Christopher S.

    2009-02-26

    Reducing the dimension of vectors used in training support vector machines (SVMs) results in a proportional speedup in training time. For large-scale problems this can make the difference between tractable and intractable training tasks. However, it is critical that classifiers trained on reduced datasets perform as reliably as their counterparts trained on high-dimensional data. We assessed principal component analysis (PCA) and sequential project pursuit (SPP) as dimension reduction strategies in the biology application of classifying proteins into well-defined functional ‘families’ (SVM-based protein family classification) by their impact on run-time, sensitivity and selectivity. Homology vectors of 4352 elements were reduced to approximately 2% of the original data size without significantly affecting accuracy using PCA and SPP, while leading to approximately a 28-fold speedup in run-time.

  20. Significantly improved dehydrogenation of ball-milled MgH2 doped with CoFe2O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Shan, Jiawei; Li, Ping; Wan, Qi; Zhai, Fuqiang; Zhang, Jun; Li, Ziliang; Liu, Zhaojiang; Volinsky, Alex A.; Qu, Xuanhui

    2014-12-01

    CoFe2O4 nanoparticles are added to magnesium hydride (MgH2) by high-energy ball milling in order to improve its hydriding properties. The hydrogen storage properties and catalytic mechanism are investigated by pressure-composition-temperature (PCT), differential thermal analysis (DTA), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The nonisothermal desorption results show that the onset desorption temperature of the MgH2 + 7 mol% CoFe2O4 is 160 °C, which is 200 °C lower than of the as-received MgH2. The dehydrogenation process of the MgH2 doped with the CoFe2O4 nanoparticles includes two steps. DTA curves and XRD patterns reveal that a chemical reaction happens between MgH2 and CoFe2O4, forming the final products of the ternary combination, corresponding to Co3Fe7, MgO and Co. The onset desorption temperature of the ball-milled MgH2 doped with Co3Fe7, MgO and Co is about 260 °C, approximately 100 °C lower than the un-doped MgH2, demonstrating that the ternary combination (Co3Fe7, MgO, and Co) also has a great catalytic effect on the MgH2 hydrogen storage properties. It is also confirmed that the various methods of adding the ternary combination have different effects on the MgH2 hydriding-dehydriding process.

  1. Teachers' Knowledge of the Relationship of Auditory Acuity and Hearing Impairment to Reading.

    ERIC Educational Resources Information Center

    Marshall, Evelyn Myrtle

    Teacher's knowledge of the relationship of auditory acuity and hearing impairment to reading was evaluated with 60 teachers and specialists (regular classroom primary and upper elementary teachers, reading teachers, teachers of the learning disabled, teachers of the hearing impaired, and speech and language pathologists). Ss were administered a…

  2. The Effects of Drift and Displacement Motion on Dynamic Visual Acuity

    ERIC Educational Resources Information Center

    Aznar-Casanova, J. Antonio; Quevedo, Lluisa; Sinnett, Scott

    2005-01-01

    Dynamic Visual Acuity (DVA) can be measured from two types of equivalently considered movement referred to as drifting-motion and displacement-motion. Displacement motion can be best described as the horizontal displacement of a stimulus, thus implying pursuit eye movements, and involves moving the stimulus from the fixation point of gaze towards…

  3. Technology as an Aid in Assessing Visual Acuity in Severely/Profoundly Retarded Children.

    ERIC Educational Resources Information Center

    Longo, Julie; And Others

    1982-01-01

    Technology has been used to measure visual acuity with the severely or profoundly mentally retarded child. The following categories of technology have been used for assessment: the recording of visual fixation within the habituation paradigm; equipment to measure eye movements and pursuits; operant techniques; and electrodiagnostic techniques…

  4. A Close Eye on the Eagle-Eyed Visual Acuity Hypothesis of Autism

    ERIC Educational Resources Information Center

    Bolte, Sven; Schlitt, Sabine; Gapp, Volker; Hainz, Daniela; Schirman, Shella; Poustka, Fritz; Weber, Bernhard; Freitag, Christine; Ciaramidaro, Angela; Walter, Henrik

    2012-01-01

    Autism spectrum disorders (ASD) have been associated with sensory hypersensitivity. A recent study reported visual acuity (VA) in ASD in the region reported for birds of prey. The validity of the results was subsequently doubted. This study examined VA in 34 individuals with ASD, 16 with schizophrenia (SCH), and 26 typically developing (TYP).…

  5. Effects of Spatial Position and Density on Visual Acuity. Umea Psychological Reports No. 153.

    ERIC Educational Resources Information Center

    Brannstrom, Lauritz

    Visual acuity as a function of target position and density was measured in a letter recognition task. A homogeneous pattern of equally-spaced elements was tachistoscopically exposed, where the target was never located at the boundaries of the pattern. The target was marked with a spatial cue to control attentional processes. With such a spatial…

  6. The use of predictive lithostratigraphy to significantly improve the ability to forecast reservoir and source rocks? Final CRADA report.

    SciTech Connect

    Doctor, R. D.; Moore, T. L.; Energy Systems

    2010-06-29

    The purpose of this CRADA, which ended in 2003, was to make reservoir and source rock distribution significantly more predictable by quantifying the fundamental controls on stratigraphic heterogeneity. To do this, the relationships among insolation, climate, sediment supply, glacioeustasy, and reservoir and source rock occurrence were investigated in detail. Work current at the inception of the CRADA had uncovered previously unrecognized associations among these processes and properties that produce a phenomenon that, when properly analyzed, will make lithostratigraphic variability (including texture, porosity, and permeability) substantially more understandable. Computer climate simulations of selected time periods, compared with the global distribution of paleoclimatic indicators, documented spatial and temporal climate changes as a function of insolation and provided quantitative changes in runoff, lake level, and glacioeustasy. The effect of elevation and climate on sediment yield was assessed numerically by analyzing digital terrain and climate data. The phase relationships of climate, yield, and glacioeustatic cycles from the Gulf of Mexico and/or other sedimentary basins were assessed by using lacunarity, a statistical technique.

  7. Combined Statistical Analyses of Peptide Intensities and Peptide Occurrences Improves Identification of Significant Peptides from MS-based Proteomics Data

    SciTech Connect

    Webb-Robertson, Bobbie-Jo M.; McCue, Lee Ann; Waters, Katrina M.; Matzke, Melissa M.; Jacobs, Jon M.; Metz, Thomas O.; Varnum, Susan M.; Pounds, Joel G.

    2010-11-01

    Liquid chromatography-mass spectrometry-based (LC-MS) proteomics uses peak intensities of proteolytic peptides to infer the differential abundance of peptides/proteins. However, substantial run-to-run variability in peptide intensities and observations (presence/absence) of peptides makes data analysis quite challenging. The missing abundance values in LC-MS proteomics data are difficult to address with traditional imputation-based approaches because the mechanisms by which data are missing are unknown a priori. Data can be missing due to random mechanisms such as experimental error, or non-random mechanisms such as a true biological effect. We present a statistical approach that uses a test of independence known as a G-test to test the null hypothesis of independence between the number of missing values and the experimental groups. We pair the G-test results evaluating independence of missing data (IMD) with a standard analysis of variance (ANOVA) that uses only means and variances computed from the observed data. Each peptide is therefore represented by two statistical confidence metrics, one for qualitative differential observation and one for quantitative differential intensity. We use two simulated and two real LC-MS datasets to demonstrate the robustness and sensitivity of the ANOVA-IMD approach for assigning confidence to peptides with significant differential abundance among experimental groups.

  8. Appropriate Fe (II) Addition Significantly Enhances Anaerobic Ammonium Oxidation (Anammox) Activity through Improving the Bacterial Growth Rate

    PubMed Central

    Liu, Yiwen; Ni, Bing-Jie

    2015-01-01

    The application of anaerobic ammonium oxidation (Anammox) process is often limited by the slow growth rate of Anammox bacteria. As the essential substrate element that required for culturing Anammox sludge, Fe (II) is expected to affect Anammox bacterial growth. This work systematically studied the effects of Fe (II) addition on Anammox activity based on the kinetic analysis of specific growth rate using data from batch tests with an enriched Anammox sludge at different dosing levels. Results clearly demonstrated that appropriate Fe (II) dosing (i.e., 0.09 mM) significantly enhanced the specific Anammox growth rate up to 0.172 d−1 compared to 0.118 d−1 at regular Fe (II) level (0.03 mM). The relationship between Fe (II) concentration and specific Anammox growth rate was found to be well described by typical substrate inhibition kinetics, which was integrated into currently well-established Anammox model to describe the enhanced Anammox growth with Fe (II) addition. The validity of the integrated Anammox model was verified using long-term experimental data from three independent Anammox reactors with different Fe (II) dosing levels. This Fe (II)-based approach could be potentially implemented to enhance the process rate for possible mainstream application of Anammox technology, in order for an energy autarchic wastewater treatment. PMID:25644239

  9. Appropriate Fe (II) Addition Significantly Enhances Anaerobic Ammonium Oxidation (Anammox) Activity through Improving the Bacterial Growth Rate

    NASA Astrophysics Data System (ADS)

    Liu, Yiwen; Ni, Bing-Jie

    2015-02-01

    The application of anaerobic ammonium oxidation (Anammox) process is often limited by the slow growth rate of Anammox bacteria. As the essential substrate element that required for culturing Anammox sludge, Fe (II) is expected to affect Anammox bacterial growth. This work systematically studied the effects of Fe (II) addition on Anammox activity based on the kinetic analysis of specific growth rate using data from batch tests with an enriched Anammox sludge at different dosing levels. Results clearly demonstrated that appropriate Fe (II) dosing (i.e., 0.09 mM) significantly enhanced the specific Anammox growth rate up to 0.172 d-1 compared to 0.118 d-1 at regular Fe (II) level (0.03 mM). The relationship between Fe (II) concentration and specific Anammox growth rate was found to be well described by typical substrate inhibition kinetics, which was integrated into currently well-established Anammox model to describe the enhanced Anammox growth with Fe (II) addition. The validity of the integrated Anammox model was verified using long-term experimental data from three independent Anammox reactors with different Fe (II) dosing levels. This Fe (II)-based approach could be potentially implemented to enhance the process rate for possible mainstream application of Anammox technology, in order for an energy autarchic wastewater treatment.

  10. Visual acuity testability and comparability in Australian preschool children: The Sydney Paediatric Eye Disease Study

    PubMed Central

    Leone, J F; Gole, G A; Mitchell, P; Kifley, A; Pai, A S-I; Rose, K A

    2012-01-01

    Purpose To establish standardised protocols for vision screening, testability and comparability of three different vision tests were examined in a population-based, cross-sectional sample of preschool children (Sydney Paediatric Eye Disease Study). Methods Measurement of presenting monocular distance visual acuity (VA) using the Amblyopia Treatment Study (ATS) HOTV protocol, was attempted by all (1774) children aged≥24 months. In addition, in children aged≥60 months (576), VA was also tested using the logMAR retro-illuminated HOTV or Early Treatment Diabetic Retinopathy Study (ETDRS) linear charts (CSV 1000). Children able to have both eyes tested monocularly were considered. Results Testability significantly increased with age for all VA tests. The ATS HOTV with an overall testability of 80% (females: 82%, males: 78%) was the most testable of the VA tests (P<0.0001). In children aged <3 years testability was low (≤47%) rising to≥80% in children aged≥3. In children≥60 months, testability was higher for the HOTV (94%) than the ETDRS (59%) chart. In those that did two VA tests, mean difference of the ATS HOTV compared with the HOTV(CSV) was −0.1, and compared with ETDRS was −0.12 (P<0.0001). Conclusions Children aged <3 years had poor VA testability, whereas those 3 years and above were highly testable using the ATS HOTV. The HOTV (CSV) retro-illuminated test was appropriate for children aged >5 years, and may be possible in younger children with early educational exposure. When comparing VA measures using these tests, the higher VA attained using the ATS HOTV, needs to be taken into account. PMID:22498798

  11. Post-exposure Treatment with Anti-rabies VHH and Vaccine Significantly Improves Protection of Mice from Lethal Rabies Infection

    PubMed Central

    Terryn, Sanne; Francart, Aurélie; Rommelaere, Heidi; Stortelers, Catelijne; Van Gucht, Steven

    2016-01-01

    Post-exposure prophylaxis (PEP) against rabies infection consists of a combination of passive immunisation with plasma-derived human or equine immune globulins and active immunisation with vaccine delivered shortly after exposure. Since anti-rabies immune globulins are expensive and scarce, there is a need for cheaper alternatives that can be produced more consistently. Previously, we generated potent virus-neutralising VHH, also called Nanobodies, against the rabies glycoprotein that are effectively preventing lethal disease in an in vivo mouse model. The VHH domain is the smallest antigen-binding functional fragment of camelid heavy chain-only antibodies that can be manufactured in microbial expression systems. In the current study we evaluated the efficacy of half-life extended anti-rabies VHH in combination with vaccine for PEP in an intranasal rabies infection model in mice. The PEP combination therapy of systemic anti-rabies VHH and intramuscular vaccine significantly delayed the onset of disease compared to treatment with anti-rabies VHH alone, prolonged median survival time (35 versus 14 days) and decreased mortality (60% versus 19% survival rate), when treated 24 hours after rabies virus challenge. Vaccine alone was unable to rescue mice from lethal disease. As reported also for immune globulins, some interference of anti-rabies VHH with the antigenicity of the vaccine was observed, but this did not impede the synergistic effect. Post exposure treatment with vaccine and human anti-rabies immune globulins was unable to protect mice from lethal challenge. Anti-rabies VHH and vaccine act synergistically to protect mice after rabies virus exposure, which further validates the possible use of anti-rabies VHH for rabies PEP. PMID:27483431

  12. Constitutive overexpression of the TaNF-YB4 gene in transgenic wheat significantly improves grain yield.

    PubMed

    Yadav, Dinesh; Shavrukov, Yuri; Bazanova, Natalia; Chirkova, Larissa; Borisjuk, Nikolai; Kovalchuk, Nataliya; Ismagul, Ainur; Parent, Boris; Langridge, Peter; Hrmova, Maria; Lopato, Sergiy

    2015-11-01

    Heterotrimeric nuclear factors Y (NF-Ys) are involved in regulation of various vital functions in all eukaryotic organisms. Although a number of NF-Y subunits have been characterized in model plants, only a few have been functionally evaluated in crops. In this work, a number of genes encoding NF-YB and NF-YC subunits were isolated from drought-tolerant wheat (Triticum aestivum L. cv. RAC875), and the impact of the overexpression of TaNF-YB4 in the Australian wheat cultivar Gladius was investigated. TaNF-YB4 was isolated as a result of two consecutive yeast two-hybrid (Y2H) screens, where ZmNF-YB2a was used as a starting bait. A new NF-YC subunit, designated TaNF-YC15, was isolated in the first Y2H screen and used as bait in a second screen, which identified two wheat NF-YB subunits, TaNF-YB2 and TaNF-YB4. Three-dimensional modelling of a TaNF-YB2/TaNF-YC15 dimer revealed structural determinants that may underlie interaction selectivity. The TaNF-YB4 gene was placed under the control of the strong constitutive polyubiquitin promoter from maize and introduced into wheat by biolistic bombardment. The growth and yield components of several independent transgenic lines with up-regulated levels of TaNF-YB4 were evaluated under well-watered conditions (T1-T3 generations) and under mild drought (T2 generation). Analysis of T2 plants was performed in large deep containers in conditions close to field trials. Under optimal watering conditions, transgenic wheat plants produced significantly more spikes but other yield components did not change. This resulted in a 20-30% increased grain yield compared with untransformed control plants. Under water-limited conditions transgenic lines maintained parity in yield performance. PMID:26220082

  13. Constitutive overexpression of the TaNF-YB4 gene in transgenic wheat significantly improves grain yield

    PubMed Central

    Yadav, Dinesh; Shavrukov, Yuri; Bazanova, Natalia; Chirkova, Larissa; Borisjuk, Nikolai; Kovalchuk, Nataliya; Ismagul, Ainur; Parent, Boris; Langridge, Peter; Hrmova, Maria; Lopato, Sergiy

    2015-01-01

    Heterotrimeric nuclear factors Y (NF-Ys) are involved in regulation of various vital functions in all eukaryotic organisms. Although a number of NF-Y subunits have been characterized in model plants, only a few have been functionally evaluated in crops. In this work, a number of genes encoding NF-YB and NF-YC subunits were isolated from drought-tolerant wheat (Triticum aestivum L. cv. RAC875), and the impact of the overexpression of TaNF-YB4 in the Australian wheat cultivar Gladius was investigated. TaNF-YB4 was isolated as a result of two consecutive yeast two-hybrid (Y2H) screens, where ZmNF-YB2a was used as a starting bait. A new NF-YC subunit, designated TaNF-YC15, was isolated in the first Y2H screen and used as bait in a second screen, which identified two wheat NF-YB subunits, TaNF-YB2 and TaNF-YB4. Three-dimensional modelling of a TaNF-YB2/TaNF-YC15 dimer revealed structural determinants that may underlie interaction selectivity. The TaNF-YB4 gene was placed under the control of the strong constitutive polyubiquitin promoter from maize and introduced into wheat by biolistic bombardment. The growth and yield components of several independent transgenic lines with up-regulated levels of TaNF-YB4 were evaluated under well-watered conditions (T1–T3 generations) and under mild drought (T2 generation). Analysis of T2 plants was performed in large deep containers in conditions close to field trials. Under optimal watering conditions, transgenic wheat plants produced significantly more spikes but other yield components did not change. This resulted in a 20–30% increased grain yield compared with untransformed control plants. Under water-limited conditions transgenic lines maintained parity in yield performance. PMID:26220082

  14. Post-exposure Treatment with Anti-rabies VHH and Vaccine Significantly Improves Protection of Mice from Lethal Rabies Infection.

    PubMed

    Terryn, Sanne; Francart, Aurélie; Rommelaere, Heidi; Stortelers, Catelijne; Van Gucht, Steven

    2016-08-01

    Post-exposure prophylaxis (PEP) against rabies infection consists of a combination of passive immunisation with plasma-derived human or equine immune globulins and active immunisation with vaccine delivered shortly after exposure. Since anti-rabies immune globulins are expensive and scarce, there is a need for cheaper alternatives that can be produced more consistently. Previously, we generated potent virus-neutralising VHH, also called Nanobodies, against the rabies glycoprotein that are effectively preventing lethal disease in an in vivo mouse model. The VHH domain is the smallest antigen-binding functional fragment of camelid heavy chain-only antibodies that can be manufactured in microbial expression systems. In the current study we evaluated the efficacy of half-life extended anti-rabies VHH in combination with vaccine for PEP in an intranasal rabies infection model in mice. The PEP combination therapy of systemic anti-rabies VHH and intramuscular vaccine significantly delayed the onset of disease compared to treatment with anti-rabies VHH alone, prolonged median survival time (35 versus 14 days) and decreased mortality (60% versus 19% survival rate), when treated 24 hours after rabies virus challenge. Vaccine alone was unable to rescue mice from lethal disease. As reported also for immune globulins, some interference of anti-rabies VHH with the antigenicity of the vaccine was observed, but this did not impede the synergistic effect. Post exposure treatment with vaccine and human anti-rabies immune globulins was unable to protect mice from lethal challenge. Anti-rabies VHH and vaccine act synergistically to protect mice after rabies virus exposure, which further validates the possible use of anti-rabies VHH for rabies PEP. PMID:27483431

  15. Ankle proprioceptive acuity is associated with objective as well as self-report measures of balance, mobility, and physical function.

    PubMed

    Deshpande, Nandini; Simonsick, Eleanor; Metter, E Jeffrey; Ko, Seunguk; Ferrucci, Luigi; Studenski, Stephanie

    2016-06-01

    Ankle proprioceptive information is integrated by the central nervous system to generate and modulate muscle contractions for maintaining standing balance. This study evaluated the association of ankle joint proprioception with objective and self-report measures of balance, mobility, and physical function across the adult life span. Seven hundred and ninety participants (age range 24-97 years, 362 women) who completed ankle proprioception assessment between 2010 and 2014 were included in the present study from the population-based cohort of the Baltimore Longitudinal Study of Aging (BLSA), USA. Outcome measures included ankle joint proprioception measured as threshold for perception of passive movement (TPPM); single leg stance time; perceived difficulty for standing balance; usual, fastest, and narrow-path gait speed; walking index; short physical performance battery score; and self-reported activity restriction due to fear of falling. Descriptive variables included age, sex, body mass index, education, strength, and cognition. Analyses of covariance (ANCOVA) in general linear model (GLM) or multinomial logistic regression analyses were performed, as appropriate, to test the hypothesis that balance, mobility, and physical function were significantly different according to TPPM quintiles even after adjusting for relevant covariates. Those with TPPM >2.2° consistently demonstrated poor balance, mobility, and physical function. However, with increase in challenge (single leg stance, fastest walking speed, and SPPB), TPPM >1.4° was associated with significantly worse performance. In conclusion, ankle proprioceptive acuity has an overall graded relationship with objective and self-report measures of balance, mobility, and physical function. However, the cutoff proprioceptive acuity associated with substantial decline or inability to perform could depend on the challenge induced. PMID:27146830

  16. Glare sensitivity and visual acuity after excimer laser photorefractive keratectomy for myopia

    PubMed Central

    Niesen, U.; Businger, U.; Hartmann, P.; Senn, P.; Schipper, I.

    1997-01-01

    BACKGROUND—Following excimer laser photorefractive keratectomy (PRK), an increase in glare sensitivity and a reduction in contrast sensitivity can occur owing to changes in the cornea (structure and topography). In this study, an attempt was made to quantify and document objectively a change in those subjective perceptual factors.
METHODS—Snellen visual acuity and disability glare were measured with the Berkeley glare test preoperatively as well as 1, 3, 6, 9, and 12 months postoperatively, after excimer laser photorefractive keratectomy (PRK) on 32 myopic patients (46 eyes). During the postoperative progress checks, haze was graded and contrast sensitivity was measured with the Vistech chart. All the data were statistically analysed by multiple regression.
RESULTS—One year after PRK, a reduction in visual acuity (VA) measured with the low acuity contrast chart (10%) with and without glare could still be found, despite the fact that acuity measurements with a high contrast Snellen chart showed the same VA 6 months postoperatively as well as before the treatment. The lowest VA could be measured 1 month postoperatively; thereafter, the acuity increased despite the increase in haze that occurred during the first 3 months.
CONCLUSION—Disability glare and a reduction in contrast sensitivity could be observed in most patients after PRK treatment with the Meditec laser system with its scanning slit. The future will show if new technology and a broader flattening area of 6 to 7 mm can minimise these postoperative complications.

 PMID:9059248

  17. Advancing medical-surgical nursing practice: improving management of the changing patient condition.

    PubMed

    Monroe, Heidi; Plylar, Peggy; Krugman, Mary

    2014-01-01

    Higher patient acuities and more novice nurses on medical-surgical units have Educators focused on achieving positive outcomes with changes in patient condition. An educational program was developed to enhance nurses' knowledge, skill, and confidence in assessing hemodynamics, recognizing early signs of instability, and administering vasoactive medications. The program was successful with significant knowledge improvement as well as an increased use of the Medical Emergency Team while maintaining a low number of code calls. PMID:25407973

  18. Baseline visual acuity strongly predicts visual acuity gain in patients with diabetic macular edema following anti-vascular endothelial growth factor treatment across trials

    PubMed Central

    Dugel, Pravin U; Hillenkamp, Jost; Sivaprasad, Sobha; Vögeler, Jessica; Mousseau, Marie-Catherine; Wenzel, Andreas; Margaron, Philippe; Hashmonay, Ron; Massin, Pascale

    2016-01-01

    Objective This study was designed to evaluate the correlation of baseline visual acuity (VA) with VA outcome in response to anti-vascular endothelial growth factor (VEGF) in diabetic macular edema using a retrospective analysis of nine clinical trials. The result will help assess the relevance of VA gain comparisons across trials. Methods A correlation analysis was performed between mean baseline VA and VA gain at month 12 for 1,616 diabetic macular edema patients across nine randomized clinical trials (RESOLVE, RISE, RIDE, RESTORE, RETAIN, DRCR.net Protocol I, DA VINCI, VIVID, VISTA) with anti-VEGF treatment regimens ranibizumab 0.5 mg and aflibercept 2 mg. Results The mean baseline VA ranged from 56.9 to 64.8 Early Treatment Diabetic Retinopathy Study (ETDRS) letters. The mean VA gain at month 12 ranged from 6.8 to 13.1 ETDRS letters across trials. There was a strong inverse correlation between mean baseline VA and VA gain at month 12 (r=−0.85). The mean VA at 12 months plateaued at ~70 (68.5–73.0) ETDRS letters (20/40 Snellen VA equivalent) for the anti-VEGF treatment groups from all trials, regardless of dosing regimens and agents. Conclusion Cross-trial comparisons based on changes in best-corrected visual acuity should be done cautiously and only after adjusting for best-corrected visual acuity at baseline. Furthermore, the total VA afforded by treatment appears to be subject to a plateau effect, which warrants further exploration. PMID:27366049

  19. The relationship between occlusion therapy and optotype visual acuity in children using data from the Infant Aphakia Treatment Study: A secondary analysis of a randomized clinical trial

    PubMed Central

    Drews-Botsch, Carolyn; Celano, Marianne; Cotsonis, George; Hartmann, E. Eugenie; Lambert, Scott R.

    2016-01-01

    preschool years with improved visual acuity in infants treated for unilateral congenital cataract. However, similar visual outcomes were achieved with varying amounts of patching. These conclusions are limited given limitations related to generalizability associated with using incomplete data from a clinical trial. PMID:27228110

  20. Bidirectional plasticity of cortical pattern recognition and behavioral sensory acuity

    PubMed Central

    Chapuis, Julie; Wilson, Donald A.

    2011-01-01

    Learning to adapt to a complex and fluctuating environment requires the ability to adjust neural representations of sensory stimuli. Through pattern completion processes, cortical networks can reconstruct familiar patterns from degraded input patterns, while pattern separation processes allow discrimination of even highly overlapping inputs. Here we show that the balance between pattern separation and completion is experience-dependent. Rats given extensive training with overlapping complex odorant mixtures show improved behavioral discrimination ability and enhanced cortical ensemble pattern separation. In contrast, behavioral training to disregard normally detectable differences between overlapping mixtures results in impaired cortical ensemble pattern separation (enhanced pattern completion) and impaired discrimination. This bidirectional effect was not found in the olfactory bulb, and may be due to plasticity within olfactory cortex itself. Thus pattern recognition, and the balance between pattern separation and completion, is highly malleable based on task demands and occurs in concert with changes in perceptual performance. PMID:22101640

  1. [A significant increase in intraoperative flash visual evoked potential amplitude during craniopharyngioma surgery-case report].

    PubMed

    Kawaguchi, Tomohiro; Ogawa, Yoshikazu; Fujiwara, Satoru; Tominaga, Teiji

    2015-04-01

    The flash visual evoked potential (VEP) is a useful diagnostic modality for visual preservation during surgery. Decreased VEP amplitude is recognized to indicate visual deterioration;however, whether intraoperative VEP can detect visual improvement remains unclear. We describe a craniopharyngioma case with a significant increase in VEP amplitude during surgery. A 67-year-old woman presented with progressive gait disturbance and impaired consciousness. Head magnetic resonance imaging demonstrated a sellar-suprasellar tumor compressing the optic chiasm upward with significant ventricular dilation. Her Glasgow Coma Scale was E3V3M5. Visual fields and acuity could not be examined because of impaired consciousness, and she could not see/recognize objects on a table. Preoperative VEP showed reproducible waveforms. Tumor removal by the extended transsphenoidal approach was performed with VEP monitoring. Increased VEP amplitude was observed after dural incision and persisted until the surgery ended. Postoperative VEP waveforms were also reproducible, but visual fields/acuity could not be examined because of cognitive dysfunction. Useful visual function was restored, and she became independent in daily life. The histological diagnosis was craniopharyngioma. The patient underwent ventriculo-peritoneal shunting for hydrocephalus 16 days after tumor removal. The postoperative course was uneventful and she was transferred to another hospital for rehabilitation. Intraoperative VEP may indicate visual improvement during surgery, which is a useful objective assessment for visual function in patients with impaired consciousness and cognitive dysfunction. PMID:25838303

  2. Improving near vision in presbyopic eyes by selective treatment of high-order aberrations

    PubMed Central

    Khalifa, Mounir A; Allam, Waleed A; Khalifa, Ahmed M

    2011-01-01

    Purpose Evaluation of improving near vision in presbyopic patients with low to moderate myopia with selective treatment of high-order aberrations (HOAs) using the ORK-CAM software aberrometer and a SCHWIND ESIRIS excimer laser. In this study, all HOAs except vertical coma were treated and the effect on near visual function was evaluated. Setting Horus Vision Correction Center, Alexandria, Egypt. Methods Twenty-six presbyopic patients (52 eyes) with low to moderate myopia were divided into two groups, A and B. The ORK-CAM software aberrometer was used in both groups to measure HOAs and design wavefront-guided treatment. All included eyes had total coma >0.2 μm. The Moria M2 mechanical microkeratome was used for flap making in both groups. Wavefront-guided laser-assisted in situ keratomileusis using ESIRIS laser was done for all eyes. In Group A (30 eyes) all HOAs were treated. In Group B (22 eyes) vertical coma was left untreated. Postoperative uncorrected distance visual acuity (UCVA), best corrected distance visual acuity (BCVA), uncorrected near acuity (UCNA), distance corrected near acuity (DCNA), best corrected near acuity with addition for near vision (BCNA), manifest refractive spherical equivalent (MRSE), HOAs, and contrast sensitivity for both groups were done preoperatively and at 3 months postoperatively. Results Mean age was 47.46 and 45.2 years for groups A and B, respectively. Mean preoperative MRSE was −2.37 and −2.87 D and mean preoperative total HOAs was 0.35 and 0.38 μm in groups A and B, respectively. There was no significant difference between groups regarding age, sex, preoperative MRSE, and preoperative total HOAs. After 3 months, there was no significant difference between groups in terms of UCVA, BCVA, MRSE, and contrast sensitivity. Analysis of postoperative HOAs showed significant difference in vertical coma between the two groups (P < 0.001). DCNA was significantly better in Group B (P < 0.01). Conclusion Treating low to moderate

  3. Comparison on testability of visual acuity, stereo acuity and colour vision tests between children with learning disabilities and children without learning disabilities in government primary schools

    PubMed Central

    Abu Bakar, Nurul Farhana; Chen, Ai-Hong

    2014-01-01

    Context: Children with learning disabilities might have difficulties to communicate effectively and give reliable responses as required in various visual function testing procedures. Aims: The purpose of this study was to compare the testability of visual acuity using the modified Early Treatment Diabetic Retinopathy Study (ETDRS) and Cambridge Crowding Cards, stereo acuity using Lang Stereo test II and Butterfly stereo tests and colour perception using Colour Vision Test Made Easy (CVTME) and Ishihara's Test for Colour Deficiency (Ishihara Test) between children in mainstream classes and children with learning disabilities in special education classes in government primary schools. Materials and Methods: A total of 100 primary school children (50 children from mainstream classes and 50 children from special education classes) matched in age were recruited in this cross-sectional comparative study. The testability was determined by the percentage of children who were able to give reliable respond as required by the respective tests. ‘Unable to test’ was defined as inappropriate response or uncooperative despite best efforts of the screener. Results: The testability of the modified ETDRS, Butterfly stereo test and Ishihara test for respective visual function tests were found lower among children in special education classes (P < 0.001) but not in Cambridge Crowding Cards, Lang Stereo test II and CVTME. Conclusion: Non verbal or “matching” approaches were found to be more superior in testing visual functions in children with learning disabilities. Modifications of vision testing procedures are essential for children with learning disabilities. PMID:24008790

  4. The Nursing Home Minimum Data Set for Vision and Its Association with Visual Acuity and Contrast Sensitivity

    PubMed Central

    Swanson, Mark W.; McGwin, Gerald; Elliott, Amanda F.; Owsley, Cynthia

    2009-01-01

    Objectives To evaluate the association between the Minimum Data Set's (MDS) Vision Patterns section and near and distance visual acuity and contrast sensitivity in nursing home residents. Design Cross-sectional study Setting Seventeen nursing homes in the Birmingham, Alabama area. Participants 371 nursing home residents ≥ 55 years old with Mini-mental State Exams of ≥ 13. Measurements The MDS 2.0 assessment for vision from the date closest to acuity and contrast sensitivity assessment was obtained from the resident's medical record. Acuity and contrast sensitivity were measured by the ETDRS chart and Pelli-Robson chart, respectively. Results The MDS rating of visual status was associated with both distance and near visual acuity and contrast sensitivity. The MDS performed poorly in distinguishing residents with mild versus moderate visual impairment. For residents who were rated on the MDS as having adequate vision, 45.9% had distance acuity worse than 20/40 in the better eye, 72.8% had near acuity worse than 20/40 in the better eye, and 85.8% had contrast sensitivity < 1.50. Conclusion The MDS 2.0 assessment for vision in nursing home residents is positively associated with visual acuity and contrast sensitivity, but does not adequately distinguish between individuals with mild versus moderate visual impairment and classifies many as having adequate vision who have visual impairment. The validity of the MDS 2.0 as a mechanism for triggering comprehensive eye care for nursing home residents is questionable. PMID:19187419

  5. Subthreshold Micropulse Photocoagulation for Persistent Macular Edema Secondary to Branch Retinal Vein Occlusion including Best-Corrected Visual Acuity Greater Than 20/40.

    PubMed

    Inagaki, Keiji; Ohkoshi, Kishiko; Ohde, Sachiko; Deshpande, Gautam A; Ebihara, Nobuyuki; Murakami, Akira

    2014-01-01

    To assess the efficacy of subthreshold micropulse diode laser photocoagulation (SMDLP) for persistent macular edema secondary to branch retinal vein occlusion (BRVO), including best-corrected visual acuity (BCVA) > 20/40, thirty-two patients (32 eyes) with macular edema secondary to BRVO were treated by SMDLP. After disease onset, all patients had been followed for at least 6 months prior to treatment. Baseline Snellen visual acuity was used to categorize the eyes as BCVA ≤ 20/40 (Group I) or BCVA > 20/40 (Group II). Main outcome measures were reduction in central macular thickness (CMT) in optical coherence tomography (OCT) and BCVA at 6 months. In the total subject-pool at 6 months, BCVA had not changed significantly but CMT was significantly reduced. Group I exhibited no significant change in CMT at 3 months but exhibited significant reductions at 6 and 12 months. Group II exhibited a marginally significant reduction in CMT at 3 months and a significant reduction at 6 months. In patients with persistent macular edema secondary to BRVO, SMDLP appears to control macular edema with minimal retinal damage. Our findings suggest that SMDLP is an effective treatment method for macular edema in BRVO patients with BCVA > 20/40. PMID:25276413

  6. Subthreshold Micropulse Photocoagulation for Persistent Macular Edema Secondary to Branch Retinal Vein Occlusion including Best-Corrected Visual Acuity Greater Than 20/40

    PubMed Central

    Inagaki, Keiji; Ohkoshi, Kishiko; Ohde, Sachiko; Deshpande, Gautam A.; Ebihara, Nobuyuki; Murakami, Akira

    2014-01-01

    To assess the efficacy of subthreshold micropulse diode laser photocoagulation (SMDLP) for persistent macular edema secondary to branch retinal vein occlusion (BRVO), including best-corrected visual acuity (BCVA) > 20/40, thirty-two patients (32 eyes) with macular edema secondary to BRVO were treated by SMDLP. After disease onset, all patients had been followed for at least 6 months prior to treatment. Baseline Snellen visual acuity was used to categorize the eyes as BCVA ≤ 20/40 (Group I) or BCVA > 20/40 (Group II). Main outcome measures were reduction in central macular thickness (CMT) in optical coherence tomography (OCT) and BCVA at 6 months. In the total subject-pool at 6 months, BCVA had not changed significantly but CMT was significantly reduced. Group I exhibited no significant change in CMT at 3 months but exhibited significant reductions at 6 and 12 months. Group II exhibited a marginally significant reduction in CMT at 3 months and a significant reduction at 6 months. In patients with persistent macular edema secondary to BRVO, SMDLP appears to control macular edema with minimal retinal damage. Our findings suggest that SMDLP is an effective treatment method for macular edema in BRVO patients with BCVA > 20/40. PMID:25276413

  7. Theoretical and applied aspects of night vision goggle resolution and visual acuity assessment

    NASA Astrophysics Data System (ADS)

    Task, H. Lee; Pinkus, Alan R.

    2007-04-01

    The image quality of night vision goggles is often expressed in terms of visual acuity, resolution or modulation transfer function. The primary reason for providing a measure of image quality is the underlying assumption that the image quality metric correlates with the level of visual performance that one could expect when using the device, for example, target detection or target recognition performance. This paper provides a theoretical analysis of the relationships between these three image quality metrics: visual acuity, resolution and modulation transfer function. Results from laboratory and field studies were used to relate these metrics to visual performance. These results can also be applied to non-image intensifier based imaging systems such as a helmet-mounted display coupled to an imaging sensor.

  8. Crossmodal temporal processing acuity impairment aggravates with age in developmental dyslexia.

    PubMed

    Virsu, Veijo; Lahti-Nuuttila, Pekka; Laasonen, Marja

    2003-01-23

    Temporal processing has been found to be impaired in developmental dyslexia. We investigated how aging affects crossmodal temporal processing impairment with 39 dyslexic and 40 fluent 20-59-year-old readers. Cognitive temporal acuity was measured at millisecond levels in six tasks. They consisted of order judgments of two brief non-speech stimulus pulses, the stimuli being audiotactile, visuotactile and audiovisual, and of simultaneity/nonsimultaneity detection of the pulses in two parallel three-pulse trains. Temporal acuity declined with age in both reading groups and its impairment was observed in developmental dyslexia. A new finding was that the crossmodal temporal impairment, directly relevant to reading, increased with age. The age-related exacerbation suggests a developmental neuronal deficit, possibly related to magnocells, which exists before dyslexia and is its ontogenetic cause. PMID:12505615

  9. Microactuator production via high aspect ratio, high edge acuity metal fabrication technology

    NASA Technical Reports Server (NTRS)

    Guckel, H.; Christenson, T. R.

    1993-01-01

    LIGA is a procession sequence which uses x-ray lithography on photoresist layers of several hundred micrometers to produce very high edge acuity photopolymer molds. These plastic molds can be converted to metal molds via electroplating of many different metals and alloys. The end results are high edge acuity metal parts with large structural heights. The LIGA process as originally described by W. Ehrfeld can be extended by adding a surface micromachining phase to produce precision metal parts which can be assembled to form three-dimensional micromechanisms. This process, SLIGA, has been used to fabricate a dynamometer on a chip. The instrument has been fully implemented and will be applied to tribology issues, speed-torque characterization of planar magnetic micromotors and a new family of sensors.

  10. Changes in smell acuity induced by radiation exposure of the olfactory mucosa

    SciTech Connect

    Ophir, D.; Guterman, A.; Gross-Isseroff, R.

    1988-08-01

    The effects of ionizing radiation on smell acuity were assessed in 12 patients in whom the olfactory mucosa was exposed to radiation in the course of treatment for nasopharyngeal carcinoma or pituitary adenoma. Olfactory detection thresholds for two odorants (amyl acetate and eugenol) were determined before the start of radiation therapy, within a week of termination of therapy, and 1, 3, and 6 months later. The results show clearly that smell acuity is profoundly affected by therapeutic irradiation. Thresholds had increased in all 12 patients by the end of treatment and were still high one month later. Varying degrees of recovery were noted in most patients three to six months after cessation of treatment. The fate of the sense of smell deserves more attention when considering the disability caused by irradiation to certain head and neck tumors.

  11. Photovoltaic restoration of sight with high visual acuity in rats with retinal degeneration

    NASA Astrophysics Data System (ADS)

    Palanker, D.; Goetz, G.; Lorach, H.; Mandel, Y.; Smith, R.; Boinagrov, D.; Lei, X.; Kamins, T.; Harris, J.; Mathieson, K.; Sher, A.

    2015-03-01

    Patients with retinal degeneration lose sight due to gradual demise of photoreceptors. Electrical stimulation of the surviving retinal neurons provides an alternative route for delivery of visual information. Subretinal photovoltaic arrays with 70μm pixels were used to convert pulsed near-IR light (880-915nm) into pulsed current to stimulate the nearby inner retinal neurons. Network-mediated responses of the retinal ganglion cells (RGCs) could be modulated by pulse width (1-20ms) and peak irradiance (0.5-10 mW/mm2). Similarly to normal vision, retinal response to prosthetic stimulation exhibited flicker fusion at high frequencies, adaptation to static images, and non-linear spatial summation. Spatial resolution was assessed in-vitro and in-vivo using alternating gratings with variable stripe width, projected with rapidly pulsed illumination (20-40Hz). In-vitro, average size of the electrical receptive fields in normal retina was 248+/-59μm - similar to their visible light RF size: 249+/-44μm. RGCs responded to grating stripes down to 67μm using photovoltaic stimulation in degenerate rat retina, and 28μm with visible light in normal retina. In-vivo, visual acuity in normally-sighted controls was 29+/-5μm/stripe, vs. 63+/-4μm/stripe in rats with subretinal photovoltaic arrays, corresponding to 20/250 acuity in human eye. With the enhanced acuity provided by eye movements and perceptual learning in human patients, visual acuity might exceed the 20/200 threshold of legal blindness. Ease of implantation and tiling of these wireless arrays to cover a large visual field, combined with their high resolution opens the door to highly functional restoration of sight.

  12. Variance analysis. Part I, Extending flexible budget variance analysis to acuity.

    PubMed

    Finkler, S A

    1991-01-01

    The author reviews the concepts of flexible budget variance analysis, including the price, quantity, and volume variances generated by that technique. He also introduces the concept of acuity variance and provides direction on how such a variance measure can be calculated. Part II in this two-part series on variance analysis will look at how personal computers can be useful in the variance analysis process. PMID:1870002

  13. Normal Visual Acuity and Electrophysiological Contrast Gain in Adults with High-Functioning Autism Spectrum Disorder.

    PubMed

    Tebartz van Elst, Ludger; Bach, Michael; Blessing, Julia; Riedel, Andreas; Bubl, Emanuel

    2015-01-01

    A common neurodevelopmental disorder, autism spectrum disorder (ASD), is defined by specific patterns in social perception, social competence, communication, highly circumscribed interests, and a strong subjective need for behavioral routines. Furthermore, distinctive features of visual perception, such as markedly reduced eye contact and a tendency to focus more on small, visual items than on holistic perception, have long been recognized as typical ASD characteristics. Recent debate in the scientific community discusses whether the physiology of low-level visual perception might explain such higher visual abnormalities. While reports of this enhanced, "eagle-like" visual acuity contained methodological errors and could not be substantiated, several authors have reported alterations in even earlier stages of visual processing, such as contrast perception and motion perception at the occipital cortex level. Therefore, in this project, we have investigated the electrophysiology of very early visual processing by analyzing the pattern electroretinogram-based contrast gain, the background noise amplitude, and the psychophysical visual acuities of participants with high-functioning ASD and controls with equal education. Based on earlier findings, we hypothesized that alterations in early vision would be present in ASD participants. This study included 33 individuals with ASD (11 female) and 33 control individuals (12 female). The groups were matched in terms of age, gender, and education level. We found no evidence of altered electrophysiological retinal contrast processing or psychophysical measured visual acuities. There appears to be no evidence for abnormalities in retinal visual processing in ASD patients, at least with respect to contrast detection. PMID:26379525

  14. The association of indicators of fetal growth with visual acuity and hearing among conscripts.

    PubMed

    Olsen, J; Sørensen, H T; Steffensen, F H; Sabroe, S; Gillman, M W; Fischer, P; Rothman, K J

    2001-03-01

    Impaired fetal growth is associated with increased susceptibility to several chronic diseases. We studied the association between birth weight, indicators of disproportional fetal growth, and impaired visual acuity and hearing in 4,300 conscripts from a well-defined region in Denmark from August 1, 1993, to July 31, 1994. From the standard health examination for conscripts, we obtained data on sight based on the Snellen's chart and data on hearing acuity based on audiometry. By means of record linkage, we obtained data on outcomes for the conscripts at birth from the Medical Birth Registry. From this registry, we have data on birth weight, gestational age, and birth length that were recorded from existing computerized registers based on the records of midwives. A birth weight of less than 3,000 gm and a body mass index at birth of less than 3.4 were associated with reduced visual acuity and impaired hearing. The results could be due to fetal brain programming or due to confounding, by early birth trauma or other factors. PMID:11246586

  15. Normal Visual Acuity and Electrophysiological Contrast Gain in Adults with High-Functioning Autism Spectrum Disorder

    PubMed Central

    Tebartz van Elst, Ludger; Bach, Michael; Blessing, Julia; Riedel, Andreas; Bubl, Emanuel

    2015-01-01

    A common neurodevelopmental disorder, autism spectrum disorder (ASD), is defined by specific patterns in social perception, social competence, communication, highly circumscribed interests, and a strong subjective need for behavioral routines. Furthermore, distinctive features of visual perception, such as markedly reduced eye contact and a tendency to focus more on small, visual items than on holistic perception, have long been recognized as typical ASD characteristics. Recent debate in the scientific community discusses whether the physiology of low-level visual perception might explain such higher visual abnormalities. While reports of this enhanced, “eagle-like” visual acuity contained methodological errors and could not be substantiated, several authors have reported alterations in even earlier stages of visual processing, such as contrast perception and motion perception at the occipital cortex level. Therefore, in this project, we have investigated the electrophysiology of very early visual processing by analyzing the pattern electroretinogram-based contrast gain, the background noise amplitude, and the psychophysical visual acuities of participants with high-functioning ASD and controls with equal education. Based on earlier findings, we hypothesized that alterations in early vision would be present in ASD participants. This study included 33 individuals with ASD (11 female) and 33 control individuals (12 female). The groups were matched in terms of age, gender, and education level. We found no evidence of altered electrophysiological retinal contrast processing or psychophysical measured visual acuities. There appears to be no evidence for abnormalities in retinal visual processing in ASD patients, at least with respect to contrast detection. PMID:26379525

  16. Visual acuity thresholds of juvenile loggerhead sea turtles (Caretta caretta): an electrophysiological approach.

    PubMed

    Bartol, Soraya Moein; Musick, John A; Ochs, Alfred L

    2002-01-01

    Visual evoked potentials measure dynamic properties of the visual system by recording transient electric responses of neural tissue identified to correspond to a specific visual stimulus, such as light or a striped grid. In this study, visual evoked potentials were used to test the visual acuity of juvenile loggerhead sea turtles (Caretta caretta) in water. Subject animals were fitted with a Plexiglas goggle filled with filtered seawater. Stimuli of black and white striped gratings were presented to the turtles using a slide projector directing an image onto a screen via a rotatable mirror that shifted the striped pattern laterally one-half cycle. Bioelectric activity was collected using a digital averaging computer and subdermal platinum electrodes, implanted under the head scutes directly above the optic nerve and the contralateral optic tectum. To isolate the response signal from the noise, signal averaging techniques were used when collecting visual evoked potentials. The resulting response waveforms included a robust positive-negative compound that was used to track the turtle's response to visual stimulation. Acuity thresholds for these sea turtles, which were derived from linear regressions analysis of the positive-negative compound amplitudes versus stripe size, ranged from 0.130 to 0.215. This acuity level is comparable to other inshore, shallow water marine species. PMID:11913813

  17. Optimization of Deep Drilling Performance - Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

    SciTech Connect

    Alan Black; Arnis Judzis

    2005-09-30

    This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2004 through September 2005. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all Phase 1 testing and is planning Phase 2 development.

  18. Health-related quality of life is impaired in primary hyperparathyroidism and significantly improves after surgery: a prospective study using the 15D instrument

    PubMed Central

    Ryhänen, Eeva M; Heiskanen, Ilkka; Sintonen, Harri; Välimäki, Matti J; Roine, Risto P; Schalin-Jäntti, Camilla

    2015-01-01

    Health-related quality of life (HRQoL) is frequently impaired in primary hyperparathyroidism (PHPT) but it is unclear if surgery is beneficial. The objective was to prospectively assess HRQoL in PHPT (n=124) with the 15D instrument before and after surgery, to compare it with that of a comparable sample of the general population (n=4295), and search for predictors of HRQoL and its change. HRQoL, and clinical and laboratory parameters were measured before and at 6 and 12 months after surgery. Regression techniques were used to search for predictors of HRQoL and gains from treatment. Before surgery, PHPT patients had significantly lower mean 15D score compared to controls (0.813 vs 0.904, P<0.001). Excretion, mental function, discomfort and symptoms, distress, depression, vitality, and sexual activity were most impaired (all P<0.001). Number of medications (P=0.001) and subjective symptoms (P<0.05) but not calcium or parathyroid hormone (PTH) predicted impaired HRQoL. Serum 25-hydroxyvitamin D (25OHD) was of borderline significance (P=0.051). Compared to baseline, mean 15D score improved significantly 6 months after surgery (0.813 vs 0.865, P<0.001) and the effect sustained at 1 year (0.878, P<0.001). The improvement was clinically important in 77.4% of patients (P<0.001). Educational level independently predicted improvement (P<0.005). HRQoL is severely impaired in PHPT but improves significantly after surgery. The 15D is a sensitive tool for assessing HRQoL and recognizing patients likely to benefit from surgery. PMID:26155796

  19. Health-related quality of life is impaired in primary hyperparathyroidism and significantly improves after surgery: a prospective study using the 15D instrument.

    PubMed

    Ryhänen, Eeva M; Heiskanen, Ilkka; Sintonen, Harri; Välimäki, Matti J; Roine, Risto P; Schalin-Jäntti, Camilla

    2015-09-01

    Health-related quality of life (HRQoL) is frequently impaired in primary hyperparathyroidism (PHPT) but it is unclear if surgery is beneficial. The objective was to prospectively assess HRQoL in PHPT (n=124) with the 15D instrument before and after surgery, to compare it with that of a comparable sample of the general population (n=4295), and search for predictors of HRQoL and its change. HRQoL, and clinical and laboratory parameters were measured before and at 6 and 12 months after surgery. Regression techniques were used to search for predictors of HRQoL and gains from treatment. Before surgery, PHPT patients had significantly lower mean 15D score compared to controls (0.813 vs 0.904, P<0.001). Excretion, mental function, discomfort and symptoms, distress, depression, vitality, and sexual activity were most impaired (all P<0.001). Number of medications (P=0.001) and subjective symptoms (P<0.05) but not calcium or parathyroid hormone (PTH) predicted impaired HRQoL. Serum 25-hydroxyvitamin D (25OHD) was of borderline significance (P=0.051). Compared to baseline, mean 15D score improved significantly 6 months after surgery (0.813 vs 0.865, P<0.001) and the effect sustained at 1 year (0.878, P<0.001). The improvement was clinically important in 77.4% of patients (P<0.001). Educational level independently predicted improvement (P<0.005). HRQoL is severely impaired in PHPT but improves significantly after surgery. The 15D is a sensitive tool for assessing HRQoL and recognizing patients likely to benefit from surgery. PMID:26155796

  20. Co-overexpressing a Plasma Membrane and a Vacuolar Membrane Sodium/Proton Antiporter Significantly Improves Salt Tolerance in Transgenic Arabidopsis Plants

    PubMed Central

    Pehlivan, Necla; Sun, Li; Jarrett, Philip; Yang, Xiaojie; Mishra, Neelam; Chen, Lin; Kadioglu, Asim; Shen, Guoxin; Zhang, Hong

    2016-01-01

    The Arabidopsis gene AtNHX1 encodes a vacuolar membrane-bound sodium/proton (Na+/H+) antiporter that transports Na+ into the vacuole and exports H+ into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane-bound Na+/H+ antiporter that exports Na+ to the extracellular space and imports H+ into the plant cell. Plants rely on these enzymes either to keep Na+ out of the cell or to sequester Na+ into vacuoles to avoid the toxic level of Na+ in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration >200 mM would kill AtNHX1-overexpressing or SOS1-overexpressing plants. Here it is shown that co-overexpressing AtNHX1 and SOS1 could further improve salt tolerance in transgenic Arabidopsis plants, making transgenic Arabidopsis able to tolerate up to 250 mM NaCl treatment. Furthermore, co-overexpression of AtNHX1 and SOS1 could significantly reduce yield loss caused by the combined stresses of heat and salt, confirming the hypothesis that stacked overexpression of two genes could substantially improve tolerance against multiple stresses. This research serves as a proof of concept for improving salt tolerance in other plants including crops. PMID:26985021

  1. Co-overexpressing a Plasma Membrane and a Vacuolar Membrane Sodium/Proton Antiporter Significantly Improves Salt Tolerance in Transgenic Arabidopsis Plants.

    PubMed

    Pehlivan, Necla; Sun, Li; Jarrett, Philip; Yang, Xiaojie; Mishra, Neelam; Chen, Lin; Kadioglu, Asim; Shen, Guoxin; Zhang, Hong

    2016-05-01

    The Arabidopsis gene AtNHX1 encodes a vacuolar membrane-bound sodium/proton (Na(+)/H(+)) antiporter that transports Na(+) into the vacuole and exports H(+) into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane-bound Na(+)/H(+) antiporter that exports Na(+) to the extracellular space and imports H(+) into the plant cell. Plants rely on these enzymes either to keep Na(+) out of the cell or to sequester Na(+) into vacuoles to avoid the toxic level of Na(+) in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration >200 mM would kill AtNHX1-overexpressing or SOS1-overexpressing plants. Here it is shown that co-overexpressing AtNHX1 and SOS1 could further improve salt tolerance in transgenic Arabidopsis plants, making transgenic Arabidopsis able to tolerate up to 250 mM NaCl treatment. Furthermore, co-overexpression of AtNHX1 and SOS1 could significantly reduce yield loss caused by the combined stresses of heat and salt, confirming the hypothesis that stacked overexpression of two genes could substantially improve tolerance against multiple stresses. This research serves as a proof of concept for improving salt tolerance in other plants including crops. PMID:26985021

  2. Improving Vision among Older Adults: Behavioral Training to Improve Sight

    PubMed Central

    DeLoss, Denton J.; Watanabe, Takeo; Andersen, George J.

    2015-01-01

    A major problem for the rapidly growing population of older adults (age 65 and older) is age-related declines in vision, which have been associated with increased risk of falls and vehicle crashes. Research suggests that the increased risk is associated with declines in contrast sensitivity and acuity. We examined whether perceptual learning could be used to improve age-related declines in contrast sensitivity. Older and younger adults were trained over seven days using a forced-choice orientation discrimination task with stimuli that varied in contrast with multiple levels of additive noise. The results indicate that older individuals, following training, performed as well as pre-trained college-aged participants. Improvements transferred to an untrained orientation, and were not associated with changes in retinal illuminance. Improvements in far acuity in younger individuals and near acuity in older individuals were also found. These findings indicate that behavioral interventions can greatly improve visual performance for older adults. PMID:25749697

  3. Visual Acuity Outcomes of Toric Lens Implantation in Patients Undergoing Cataract Surgery at a Residency Training Program.

    PubMed

    Sundy, Meryl; McKnight, Dustin; Eck, Craig; Rieger, Frank

    2016-01-01

    Ophthalmology residents must become competent in the use of a variety of intraocular lenses (IOLs) and refractive technologies designed to reduce spectacle use after cataract surgery. Our study of visual acuity outcomes with toric IOLs at the Harry S. Truman Memorial Veterans' Hospital revealed that residents achieved an uncorrected visual acuity of 20/40 or better in 88% of the surgeries they performed, a rate comparable to that reported by other residency programs and by cataract surgeons. PMID:27039489

  4. One of the most well-established age-related changes in neural activity disappears after controlling for visual acuity.

    PubMed

    Porto, Fábio H G; Tusch, Erich S; Fox, Anne M; Alperin, Brittany R; Holcomb, Phillip J; Daffner, Kirk R

    2016-04-15

    Numerous studies using a variety of imaging techniques have reported age-related differences in neural activity while subjects carry out cognitive tasks. Surprisingly little attention has been paid to the potential impact of age-associated changes in sensory acuity on these findings. Studies in the visual modality frequently report that their subjects had "normal or corrected- to-normal vision." However, in most cases, there is no indication that visual acuity was actually measured, and it is likely that the investigators relied largely on self-reported visual status of subjects, which is often inaccurate. We investigated whether differences in visual acuity influence one of the most commonly observed findings in the event-related potentials literature on cognitive aging, a reduction in posterior P3b amplitude, which is an index of cognitive decision-making/updating. Well-matched young (n=26) and old adults (n=29) participated in a visual oddball task. Measured visual acuity with corrective lenses was worse in old than young adults. Results demonstrated that the robust age-related decline in P3b amplitude to visual targets disappeared after controlling for visual acuity, but was unaffected by accounting for auditory acuity. Path analysis confirmed that the relationship between age and diminished P3b to visual targets was mediated by visual acuity, suggesting that conveyance of suboptimal sensory data due to peripheral, rather than central, deficits may undermine subsequent neural processing. We conclude that until the relationship between age-associated differences in visual acuity and neural activity during experimental tasks is clearly established, investigators should exercise caution attributing results to differences in cognitive processing. PMID:26825439

  5. Evaluation of a Public Child Eye Health Tertiary Facility for Pediatric Cataract in Southern Nigeria I: Visual Acuity Outcome

    PubMed Central

    Duke, Roseline E.; Adio, Adedayo; Oparah, Sidney K.; Odey, Friday; Eyo, Okon A.

    2016-01-01

    Purpose: A retrospective study of the outcome of congenital and developmental cataract surgery was conducted in a public child eye health tertiary facility in children <16 years of age in Southern Nigeria, as part of an evaluation. Materials and Method: Manual Small Incision Cataract Surgery with or without anterior vitrectomy was performed. The outcome measures were visual acuity (VA) and change (gain) in visual acuity. The age of the child at onset, duration of delay in presentation, ocular co-morbidity, non ocular co-morbidity, gender, and pre operative visual acuity were matched with postoperative visual acuity. A total of 66 children were studied for a period of six weeks following surgery. Results: Forty eight (72.7%) children had bilateral congenital cataracts and 18 (27.3%) children had bilateral developmental cataracts. There were 38(57.6%) males and 28 (42.4%) females in the study. Thirty Five (53%) children had good visual outcome (normal vision range 6/6/ -6/18) post-operatively. The number of children with blindness (vision <3/60) decreased from 61 (92.4%) pre-operatively to 4 (6.1%) post-operatively. Post operative complication occurred in 6.8% of cases six week after surgery. Delayed presentation had an inverse relationship with change (gain) in visual acuity (r = - 0.342; p-value = 0.005). Pre-operative visual acuity had a positive relationship with post operative change (gain) in visual acuity (r = 0.618; p-value = 0.000). Conclusion: Predictors of change in visual acuity in our study were; delayed presentation and pre-operative VA. Cataract surgery in children showed clinical benefit. PMID:27347247

  6. Myopia prevention, near work, and visual acuity of college students: integrating the theory of planned behavior and self-determination theory.

    PubMed

    Chan, Derwin King-Chung; Fung, Ying-Ki; Xing, Suxuan; Hagger, Martin S

    2014-06-01

    There has been little research examining the psychological antecedents of safety-oriented behavior aimed at reducing myopia risk. This study utilizes self-determination theory (SDT) and the theory of planned behavior (TPB) to understand the role of motivational and social-cognitive factors on individuals' near-work behavior. Adopting a prospective design, undergraduate students (n = 107) completed an initial questionnaire based on SDT in week 1, a second questionnaire containing measures of TPB variables in week 2, and objective measures of reading distance and visual acuity in week 6. The data were analyzed by variance-based structural equation modeling. The results showed that perceived autonomy support and autonomous motivation from SDT significantly predicted attitude, subjective norm, and perceived behavioral control from the TPB. These social-cognitive factors were significantly associated with intention and intention significantly predicted reading distance. The relationships in the model held when controlling for visual acuity. In conclusion, the integrated model of SDT and the TPB may help explain myopia-preventive behaviors. PMID:23404136

  7. Combined therapy with thrombospondin-1 type I repeats (3TSR) and chemotherapy induces regression and significantly improves survival in a preclinical model of advanced stage epithelial ovarian cancer

    PubMed Central

    Russell, Samantha; Duquette, Mark; Liu, Joyce; Drapkin, Ronny; Lawler, Jack; Petrik, Jim

    2015-01-01

    Most women are diagnosed with epithelial ovarian cancer (EOC) at advanced stage, where therapies have limited effectiveness and the long-term survival rate is low. We evaluated the effects of combined antiangiogenic and chemotherapy treatments on advanced stage EOC. Treatment of EOC cells with a recombinant version of the thrombospondin-1 type I repeats (3TSR) induced more apoptotic cell death (36.5 ± 9.6%) in vitro compared to untreated controls (4.1 ± 1.4). In vivo, tumors were induced in an orthotopic, syngeneic mouse model of advanced stage EOC. Mice were treated with 3TSR (4 mg/kg per day) alone or in combination with chemotherapy drugs delivered with maximum tolerated dose or metronomic scheduling. Pretreatment with 3TSR induced tumor regression, normalized tumor vasculature, and improved uptake of chemotherapy drugs. Combination 3TSR and metronomic chemotherapy induced the greatest tumor regression (6.2-fold reduction in size compared to PBS-treated controls) and highest survival when treatment was initiated at advanced stage. 3TSR binding to its receptor, CD36 (cluster of differentiation 36), increased binding of CD36 and SHP-1, which significantly inhibited phosphorylation of the VEGF receptor. In this study, we describe a novel treatment approach and mechanism of action with 3TSR and chemotherapy that induces regression of advanced stage EOC and significantly improves survival.—Russell, S., Duquette, M., Liu, J., Drapkin, R., Lawler, J., Petrik, J. Combined therapy with thrombospondin-1 type I repeats (3TSR) and chemotherapy induces regression and significantly improves survival in a preclinical model of advanced stage epithelial ovarian cancer. PMID:25395453

  8. Pattern visual evoked potentials in the assessment of objective visual acuity in amblyopic children.

    PubMed

    Gundogan, Fatih C; Mutlu, Fatih M; Altinsoy, H Ibrahim; Tas, Ahmet; Oz, Oguzhan; Sobaci, Gungor

    2010-08-01

    The aim of this study was to determine the value of pattern visual evoked potentials (PVEP) to five consecutive check size patterns in the assessment of visual acuity (VA) in children. One hundred unilateral amblyopic (study group) and 90 healthy children with best-corrected visual acuity (BCVA) of 1.0 (control group) were planned to be included. PVEP responses to five consecutive check sizes (2 degrees , 1 degrees , 30', 15', and 7') which are assumed to correspond to VAs of 0.1, 0.2, 0.4, 0.7 and 1.0 Snellen lines were recorded in both groups. Eighty-five children in the study group (85.0%) and 74 children in the control group (82.2%) who cooperated well with PVEP testing were included. Normal values for latency, amplitude, and normalized interocular amplitude/latency difference in each check size were defined in the control group. PVEP-estimated VA (PVEP-VA) in the amblyopic eye was defined by the normal PVEP responses to the smallest check size associated with normal interocular difference from the non-amblyopic eye, and was considered predictive if it is within +/-1 Snellen line (1 decimal) discrepancy with BCVA in that eye. Mean age was 9.7 +/- 1.9 and 9.9 +/- 2.2 years in the study and the control groups, respectively. LogMAR (logarithm of minimum angle of resolution) Snellen acuity was well correlated with the logMAR PVEP-VA (r = 0.525, P < 0.001) in the study group. The Snellen line discrepancy between BCVA and PVEP-VA was within +/-1 Snellen line in 57.6% of the eyes. PVEP to five consecutive check sizes may predict objective VA in amblyopic children. PMID:20376691

  9. Crowding is proportional to visual acuity in young and aging eyes.

    PubMed

    Yehezkel, Oren; Sterkin, Anna; Lev, Maria; Polat, Uri

    2015-01-01

    Spatial crowding decreases object recognition and conscious visual perception in clutter. In a previous study we used brief presentation times to reveal the effects of a crowded presentation in the fovea. Here we aimed to test the relationships between varying visual acuity (VA) and crowding in the fovea, under the assumption that in uncorrected presbyopia, the processing is relatively normal, whereas the retinal input is blurred. We tested whether normal participants whose near VA is gradually reduced due to age-related deterioration (presbyopia, or "aging eye") will show an acuity-dependent increase in foveal crowding. We used brief presentations and acuity-threshold letter targets in order to magnify the crowding-effect amplitude in the fovea. A total of 195 participants with an age range of 20-68 years and an average of 44.3 ± 11.7 years (M ± SD) were divided into four age groups, all without any optical correction for the near distance. Our findings show that crowding is proportional to VA. This proportionality is affected by VA-age dependency, with a nonlinear S-shaped pattern: A steep VA reduction begins to develop, which is compatible with the normal onset age of presbyopia symptoms and a saturation in the VA-age dependency in the oldest age group, for which we propose a VA-eccentricity account. Finally, there is a high variance in the crowding amplitude in the young, even before the onset age of presbyopia symptoms, suggesting crowding conditions with limited presentation times as a highly sensitive measure of VA, which predicts visual performance in complex tasks, such as reading. PMID:26129861

  10. An Industry/DOE Program to Develop and Benchmark Advanced Diamond Product Drill Bits and HP/HT Drilling Fluids to Significantly Improve Rates of Penetration

    SciTech Connect

    TerraTek

    2007-06-30

    A deep drilling research program titled 'An Industry/DOE Program to Develop and Benchmark Advanced Diamond Product Drill Bits and HP/HT Drilling Fluids to Significantly Improve Rates of Penetration' was conducted at TerraTek's Drilling and Completions Laboratory. Drilling tests were run to simulate deep drilling by using high bore pressures and high confining and overburden stresses. The purpose of this testing was to gain insight into practices that would improve rates of penetration and mechanical specific energy while drilling under high pressure conditions. Thirty-seven test series were run utilizing a variety of drilling parameters which allowed analysis of the performance of drill bits and drilling fluids. Five different drill bit types or styles were tested: four-bladed polycrystalline diamond compact (PDC), 7-bladed PDC in regular and long profile, roller-cone, and impregnated. There were three different rock types used to simulate deep formations: Mancos shale, Carthage marble, and Crab Orchard sandstone. The testing also analyzed various drilling fluids and the extent to which they improved drilling. The PDC drill bits provided the best performance overall. The impregnated and tungsten carbide insert roller-cone drill bits performed poorly under the conditions chosen. The cesium formate drilling fluid outperformed all other drilling muds when drilling in the Carthage marble and Mancos shale with PDC drill bits. The oil base drilling fluid with manganese tetroxide weighting material provided the best performance when drilling the Crab Orchard sandstone.

  11. [Urgency and acuity judgment systems before medical care (emergency telephone consultation center #7119, JTAS etc.)].

    PubMed

    Ishikawa, Hideki; Yoshida, Masashi; Sakamoto, Tetsuya

    2016-02-01

    Currently growing the demand of the emergency medical care in Japan, sharing the concept about medical urgency is needed in the whole society in order to maintain the emergency medical systems as social resources. The present conditions and challenges are outlined: Emergency Telephone Consultation Center in Tokyo Fire Department (established in June 2007) and on-site triage as representatives of "pre-hospital urgency determination systems", and JTAS (Japan Triage and Acuity System, introduced in April 2012) as a representative of "in-hospital, pre-examination urgency determination systems". PMID:26915257

  12. Successful Application of a Canadian Mental Health Curriculum Resource by Usual Classroom Teachers in Significantly and Sustainably Improving Student Mental Health Literacy

    PubMed Central

    Kutcher, Stan; Wei, Yifeng; Morgan, Catherine

    2015-01-01

    Objective: To investigate whether the significant and substantive findings from a previous study of youth mental health literacy (MHL) could be replicated using the same methods in another population. Method: We examined the impact of a curriculum resource, the Mental Health and High School Curriculum Guide (The Guide), taught by usual classroom teachers on students’ knowledge and attitudes related to mental health and mental illness in Canadian secondary schools. Survey data were collected before, immediately after, and 2 months after implementation of The Guide by teachers in usual classroom teaching. We conducted paired-sample t tests and calculated the Cohen d value to determine outcomes and impact of the curriculum resource application. Results: One hundred fourteen students were matched for analysis of knowledge data and 112 students were matched for analysis of attitude data at pre-intervention, post-intervention, and 2-month follow-up time periods. Following classroom exposure to the curriculum resource, students’ knowledge scores increased significantly and substantively, compared with baseline (P < 0.001, d = 1.11), and this was maintained at 2-month follow-up (P < 0.001, d = 0.91). Similar findings for attitude improvement were found (P < 0.001, d = 0.66), and this improvement was maintained at 2-month follow-up (P < 0.001, d = 0.52). Conclusions: These findings corroborate those from a previous study conducted in a different location. Taken together these results suggest a simple but effective approach to improving MHL in young people by embedding a classroom resource, delivered by usual classroom teachers in usual school settings. PMID:26720827

  13. Long-term preservation of cone photoreceptors and visual acuity in rd10 mutant mice exposed to continuous environmental enrichment

    PubMed Central

    Strettoi, Enrica

    2014-01-01

    year of age showed major degeneration of the photoreceptor layer in both experimental groups, with small clusters of photoreceptors persisting in the peripheral retina. These vestigial cells were positive for L and M opsins and cone arrestin and represented the residual population of cones. In the retinas of the EE mice, cones were more numerous and less remodeled than in the ST counterparts, albeit virtually devoid of outer segments, as confirmed with electron microscopy (EM) observations. Cone counting in retinal whole mounts showed that rd10 EE mice at 1 year had almost three times as many surviving cones (34,000±4,000) as the ST control mice (12,700±1,800), t test p=0.003. Accordingly, the rd10 EE mice at 1 year of age were still capable of performing the visual water task in photopic conditions, showing a residual visual acuity of 0.138±0 cycles/degree. This ability was virtually absent in the rd10 ST age-matched mice (0.063±0.014), t test, p=0.029. No major differences were detected in the morphology of the neurons of the inner retina between the two experimental groups. Conclusions The approaches used to test the effects of an EE were consistent in showing significantly better preservation of cones and measurable visual acuity in 1-year-old rd10 EE mice. We therefore confirm and extend previous findings that showed an EE is an effective, minimally invasive tool for promoting long-lasting retinal protection in experimental models of RP. PMID:25489227

  14. The Cataract National Dataset electronic multi-centre audit of 55 567 operations: risk indicators for monocular visual acuity outcomes

    PubMed Central

    Sparrow, J M; Taylor, H; Qureshi, K; Smith, R; Birnie, K; Johnston, R L

    2012-01-01

    Aims To report risk factors for visual acuity (VA) improvement and harm following cataract surgery using electronically collected multi-centre data conforming to the Cataract National Dataset (CND). Methods Routinely collected anonymised data were remotely extracted from the electronic patient record systems of 12 participating NHS Trusts undertaking cataract surgery. Following data checks and cleaning, analyses were performed to identify risk indicators for: (1) a good acuity outcome (VA 6/12 or better), (2) the pre- to postoperative change in VA, and (3) VA loss (doubling or worse of the visual angle). Results In all, 406 surgeons from 12 NHS Trusts submitted data on 55 567 cataract operations. Preoperative VA was known for 55 528 (99.9%) and postoperative VA outcome for 40 758 (73.3%) operations. Important adverse preoperative risk indicators found in at least 2 of the 3 analyses included older age (3), short axial length (3), any ocular comorbidity (3), age-related macular degeneration (2), diabetic retinopathy (3), amblyopia (2), corneal pathology (2), previous vitrectomy (2), and posterior capsule rupture (PCR) during surgery (3). PCR was the only potentially modifiable adverse risk indicator and was powerfully associated with VA loss (OR=5.74). Conclusion Routinely collected electronic data conforming to the CND provide sufficient detail for identification and quantification of preoperative risk indicators for VA outcomes of cataract surgery. The majority of risk indicators are intrinsic to the patient or their eye, with a notable exception being PCR during surgery. PMID:22441022

  15. Test Re-Test Reliability and Validity of Different Visual Acuity and Stereoacuity Charts Used in Preschool Children

    PubMed Central

    Moganeswari, Diana; Srinivasan, Krithica; Jacob, George P

    2015-01-01

    Background Preschool vision screenings are cost effective ways to detect children with vision impairments. The use of any vision tests in children must be age appropriate, testable, repeatable and valid. Aim To compare the test re-test reliability, sensitivity and specificity of different visual acuity and stereo acuity charts used in preschool children. Materials and Methods Monocular visual acuity of 90 subjects (180 eyes) of age 36 to 71 months was assessed with HOTV, Lea and E-chart in a preschool located in a semi urban area, Manipal, Karnataka. After the vision assessment, stereo acuity was recorded using Frisby and Titmus stereo charts followed by comprehensive eye examination. Repeated measurements of visual acuity and stereo acuity were done one week after the initial assessment. Results Mean age of children was 53± 10 months with equal gender distribution. Intra class correlation (ICC) of Lea, HOTV, E-chart, Frisby and Titmus charts were 0.96, 0.99, 0.92, 1.0 and 1.0 respectively. The area under receiver operating curve (ROC) for Lea and E-chart was 0.892 and 0.776. HOTV was considered as the gold standard as it showed the least difference on repeated measurements. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of E-chart was 99, 15, 45, 94 and 21.8 percent, and Lea was 93, 56, 59 and 92 percent. The sensitivity, specificity, PPV and NPV of Frisby was 75, 27, 9, 92 percent were as of Titmus was 75, 13, 8 and 85 percent respectively. Conclusion HOTV chart can be used as the gold standard for measuring visual acuity of pre-schoolers in a semi urban area. Lea chart can be used in the absence of HOTV chart. Frisby and Titmus charts are good screening tools, but with poor diagnostic criteria. PMID:26675120

  16. Statewide retrospective study of low acuity emergency presentations in New South Wales, Australia: who, what, where and why?

    PubMed Central

    Dinh, Michael M; Berendsen Russell, Saartje; Bein, Kendall J; Chalkley, Dane R; Muscatello, David; Paoloni, Richard; Ivers, Rebecca

    2016-01-01

    Objective The present study aims to use a statewide population-based registry to assess the prevalence of low acuity emergency department (ED) presentations, describe the trend in presentation rates and to determine whether they were associated with various presentation characteristics such as the type of hospital as well as clinical and demographic variables. Design and setting This was a retrospective analysis of a population-based registry of ED presentations in New South Wales (NSW). Generalised estimating equations with log links were used to determine factors associated with low acuity presentations to account for repeat presentations and the possibility of clustering of outcomes. Participants Patients were included in this analysis if they presented to an ED between January 2010 and December 2014. The outcomes of interest were low acuity presentation, defined as those who self-presented (were not transported by ambulance), were assigned a triage category of 4 or 5 (semiurgent or non-urgent) and discharged back to usual residence from ED. Results There were 10.7 million ED presentations analysed. Of these, 45% were classified as a low acuity presentation. There was no discernible increase in the rate of low acuity presentations across NSW between 2010 and 2014. The strongest predictors of low acuity ED presentation were age <40 years of age (OR 1.77); injury or musculoskeletal administrative and non-urgent procedures (OR 2.96); ear, nose and throat, eye or oral (OR 5.53); skin or allergy-type presenting problems (OR 2.84). Conclusions Low acuity ED presentations comprise almost half of all ED presentations. Alternative emergency models of care may help meet the needs of these patients. PMID:27165649

  17. Modeling peripheral visual acuity enables discovery of gaze strategies at multiple time scales during natural scene search

    PubMed Central

    Ramkumar, Pavan; Fernandes, Hugo; Kording, Konrad; Segraves, Mark

    2015-01-01

    Like humans, monkeys make saccades nearly three times a second. To understand the factors guiding this frequent decision, computational models of vision attempt to predict fixation locations using bottom-up visual features and top-down goals. How do the relative influences of these factors evolve over multiple time scales? Here we analyzed visual features at fixations using a retinal transform that provides realistic visual acuity by suitably degrading visual information in the periphery. In a task in which monkeys searched for a Gabor target in natural scenes, we characterized the relative importance of bottom-up and task-relevant influences by decoding fixated from nonfixated image patches based on visual features. At fast time scales, we found that search strategies can vary over the course of a single trial, with locations of higher saliency, target-similarity, edge–energy, and orientedness looked at later on in the trial. At slow time scales, we found that search strategies can be refined over several weeks of practice, and the influence of target orientation was significant only in the latter of two search tasks. Critically, these results were not observed without applying the retinal transform. Our results suggest that saccade-guidance strategies become apparent only when models take into account degraded visual representation in the periphery. PMID:25814545

  18. Analysis of visual acuity and motion resolvability as measures for optimal visual perception of the workspace.

    PubMed

    Janabi-Sharifi, Farrokh; Vakanski, Aleksandar

    2011-03-01

    For working tasks with high visual demand, ergonomic design of the working stations requires defining criteria for comparative evaluation and analysis of the visual perceptibility in different regions of the workspace. This paper provides kinematic models of visual acuity and motion resolvability as adopted measures of visual perceptibility of the workspace. The proposed models have been examined through two sets of experiments. The first experiment is designed to compare the models outputs with those from experiments. Time measurements of the participants' response to visual events are employed for calculation of the perceptibility measures. The overall comparison results show similar patterns and moderate statistical errors of the measured and kinematically modeled values of the parameters. In the second experiment, the proposed set of visual perceptibility measures are examined for a simulated industrial task of inserting electronic chips into slots of a working table, resembling a fine assembly line of transponders manufacturing. The results from ANOVA tests for the visual acuity and the motion resolvability justify the postures adopted by the participants using visual perceptibility measures for completing the insertion tasks. PMID:20947063

  19. Visual acuity and sensitivity increase allometrically with body size in butterflies.

    PubMed

    Rutowski, R L; Gislén, Lars; Warrant, Eric J

    2009-03-01

    In insects, the surface area of the compound eye increases with body size both within and between species with only a slight negative allometry. This increase in surface area permits changes in eye structure that affect the eye's acuity and sensitivity, two features of eye performance that cannot be simultaneously maximized. Hence, as eye size varies within a lineage, so will the compromises between features that maximize acuity and those that maximize sensitivity. We examined these compromises in four species of nymphalid butterflies that varied in body mass over almost two orders of magnitude. The largest of these species was crepuscular and so additionally may indicate the potential effect of life style on eye structure. Across these species, as body size increased, facet diameters increased while interommatidial angles decreased. Finally, the eye parameter was fairly constant across species except in the crepuscular species in which some notably large values were observed in the frontal visual field. Based on our measurements, large butterflies have more acute and more sensitive vision than smaller butterflies. However, full understanding of the behavioral implications of this relationship awaits information on the temporal resolution of their eyes because typical flight velocities also increase with body size. PMID:18809509

  20. Comparison of binocular through-focus visual acuity with monovision and a small aperture inlay.

    PubMed

    Schwarz, Christina; Manzanera, Silvestre; Prieto, Pedro M; Fernández, Enrique J; Artal, Pablo

    2014-10-01

    Corneal small aperture inlays provide extended depth of focus as a solution to presbyopia. As this procedure is becoming more popular, it is interesting to compare its performance with traditional approaches, such as monovision. Here, binocular visual acuity was measured as a function of object vergence in three subjects by using a binocular adaptive optics vision analyzer. Visual acuity was measured at two luminance levels (photopic and mesopic) under several optical conditions: 1) natural vision (4 mm pupils, best corrected distance vision), 2) pure-defocus monovision ( + 1.25 D add in the nondominant eye), 3) small aperture monovision (1.6 mm pupil in the nondominant eye), and 4) combined small aperture and defocus monovision (1.6 mm pupil and a + 0.75 D add in the nondominant eye). Visual simulations of a small aperture corneal inlay suggest that the device extends DOF as effectively as traditional monovision in photopic light, in both cases at the cost of binocular summation. However, individual factors, such as aperture centration or sensitivity to mesopic conditions should be considered to assure adequate visual outcomes. PMID:25360355

  1. Binocular depth acuity research to support the modular multi-spectral stereoscopic night vision goggle

    NASA Astrophysics Data System (ADS)

    Merritt, John O.; CuQlock-Knopp, V. Grayson; Paicopolis, Peter; Smoot, Jennifer; Kregel, Mark; Corona, Bernard

    2006-05-01

    This paper discusses the depth acuity research conducted in support of the development of a Modular Multi-Spectral Stereoscopic (M2S2) night vision goggle (NVG), a customizable goggle that lets the user select one of five goggle configurations: monocular thermal, monocular image intensifier (I2), binocular I2, binocular thermal, and binocular dual-waveband (thermal imagery to one eye and I2 imagery to the other eye). The motives for the development of this type of customizable goggle were (1) the need for an NVG that allows the simultaneous use of two wavebands, (2) the need for an alternative sensor fusion method to avoid the potential image degradation that may accompany digitally fused images, (3) a requirement to provide the observer with stereoscopic, dual spectrum views of a scene, and (4) the need to handle individual user preferences for sensor types and ocular configurations employed in various military operations. Among the increases in functionality that the user will have with this system is the ability to convert from a binocular I2 device (needed for detailed terrain analysis during off-road mobility) to a monocular thermal device (for increased situational awareness in the unaided eye during nights with full moon illumination). Results of the present research revealed potential depth acuity advantages that may apply to off-road terrain hazard detection for the binocular thermal configuration. The results also indicated that additional studies are needed to address ways to minimize binocular incompatibility for the dual waveband configuration.

  2. Magnitude Representations in Williams Syndrome: Differential Acuity in Time, Space and Number Processing

    PubMed Central

    Rousselle, Laurence; Dembour, Guy; Noël, Marie-Pascale

    2013-01-01

    For some authors, the human sensitivity to numerosities would be grounded in our ability to process non-numerical magnitudes. In the present study, the developmental relationships between non numerical and numerical magnitude processing are examined in people with Williams syndrome (WS), a genetic disorder known to associate visuo-spatial and math learning disabilities. Twenty patients with WS and 40 typically developing children matched on verbal or non-verbal abilities were administered three comparison tasks in which they had to compare numerosities, lengths or durations. Participants with WS showed lower acuity (manifested by a higher Weber fraction) than their verbal matched peers when processing numerical and spatial but not temporal magnitudes, indicating that they do not present a domain-general dysfunction of all magnitude processing. Conversely, they do not differ from non-verbal matched participants in any of the three tasks. Finally, correlational analyses revealed that non-numerical and numerical acuity indexes were both related to the first mathematical acquisitions but not with later arithmetical skills. PMID:24013906

  3. The auditory spatial acuity of the domestic cat in the interaural horizontal and median vertical planes.

    PubMed

    Martin, R L; Webster, W R

    1987-01-01

    The auditory spatial acuity of the domestic cat in the interaural horizontal plane was examined using broadband noise and nine pure-tone stimuli ranging in frequency from 0.5 to 32 kHz. Acuity in the median vertical plane was also examined using broadband noise and three pure tones of frequencies 2, 8 and 16 kHz. Minimum audible angles (MAAs) for a reference source directly in front of an animal were measured in the horizontal plane for five cats and in the vertical plane for four. The smallest MAAs measured were those for the noise stimulus, for which MAAs in the horizontal and vertical planes were similar in magnitude. Horizontal plane MAAs for low-frequency tones were smaller than those for high, and the pattern of MAA change with frequency was consistent with the use of interaural phase and sound pressure level difference cues to localize low- and high-frequency tones, respectively. Three of the four cats trained on the vertical plane MAA task did not achieve criterion performance for any of the three pure tones, and the MAAs obtained from the fourth cat at each frequency were relatively large. Vertical plane performance was consistent with the use of spectral transformation cues to discern the elevation of a complex stimulus. PMID:3680067

  4. Effectiveness of exome and genome sequencing guided by acuity of illness for diagnosis of neurodevelopmental disorders

    PubMed Central

    Soden, Sarah E.; Saunders, Carol J.; Willig, Laurel K.; Farrow, Emily G.; Smith, Laurie D.; Petrikin, Josh E.; LePichon, Jean-Baptiste; Miller, Neil A.; Thiffault, Isabelle; Dinwiddie, Darrell L.; Twist, Greyson; Noll, Aaron; Heese, Bryce A.; Zellmer, Lee; Atherton, Andrea M.; Abdelmoity, Ahmed T.; Safina, Nicole; Nyp, Sarah S.; Zuccarelli, Britton; Larson, Ingrid A.; Modrcin, Ann; Herd, Suzanne; Creed, Mitchell; Ye, Zhaohui; Yuan, Xuan; Brodsky, Robert A.; Kingsmore, Stephen F.

    2014-01-01

    Neurodevelopmental disorders (NDDs) affect more than 3% of children and are attributable to single-gene mutations at more than 1000 loci. Traditional methods yield molecular diagnoses in less than one-half of children with NDD. Whole-genome sequencing (WGS) and whole-exome sequencing (WES) can enable diagnosis of NDD, but their clinical and cost-effectiveness are unknown. One hundred families with 119 children affected by NDD received diagnostic WGS and/or WES of parent-child trios, wherein the sequencing approach was guided by acuity of illness. Forty-five percent received molecular diagnoses. An accelerated sequencing modality, rapid WGS, yielded diagnoses in 73% of families with acutely ill children (11 of 15). Forty percent of families with children with nonacute NDD, followed in ambulatory care clinics (34 of 85), received diagnoses: 33 by WES and 1 by staged WES then WGS. The cost of prior negative tests in the nonacute patients was $19,100 per family, suggesting sequencing to be cost-effective at up to $7640 per family. A change in clinical care or impression of the pathophysiology was reported in 49% of newly diagnosed families. If WES or WGS had been performed at symptom onset, genomic diagnoses may have been made 77 months earlier than occurred in this study. It is suggested that initial diagnostic evaluation of children with NDD should include trio WGS or WES, with extension of accelerated sequencing modalities to high-acuity patients. PMID:25473036

  5. Simulation of thalamic prosthetic vision: reading accuracy, speed, and acuity in sighted humans

    PubMed Central

    Vurro, Milena; Crowell, Anne Marie; Pezaris, John S.

    2014-01-01

    The psychophysics of reading with artificial sight has received increasing attention as visual prostheses are becoming a real possibility to restore useful function to the blind through the coarse, pseudo-pixelized vision they generate. Studies to date have focused on simulating retinal and cortical prostheses; here we extend that work to report on thalamic designs. This study examined the reading performance of normally sighted human subjects using a simulation of three thalamic visual prostheses that varied in phosphene count, to help understand the level of functional ability afforded by thalamic designs in a task of daily living. Reading accuracy, reading speed, and reading acuity of 20 subjects were measured as a function of letter size, using a task based on the MNREAD chart. Results showed that fluid reading was feasible with appropriate combinations of letter size and phosphene count, and performance degraded smoothly as font size was decreased, with an approximate doubling of phosphene count resulting in an increase of 0.2 logMAR in acuity. Results here were consistent with previous results from our laboratory. Results were also consistent with those from the literature, despite using naive subjects who were not trained on the simulator, in contrast to other reports. PMID:25408641

  6. Comparison of binocular through-focus visual acuity with monovision and a small aperture inlay

    PubMed Central

    Schwarz, Christina; Manzanera, Silvestre; Prieto, Pedro M.; Fernández, Enrique J.; Artal, Pablo

    2014-01-01

    Corneal small aperture inlays provide extended depth of focus as a solution to presbyopia. As this procedure is becoming more popular, it is interesting to compare its performance with traditional approaches, such as monovision. Here, binocular visual acuity was measured as a function of object vergence in three subjects by using a binocular adaptive optics vision analyzer. Visual acuity was measured at two luminance levels (photopic and mesopic) under several optical conditions: 1) natural vision (4 mm pupils, best corrected distance vision), 2) pure-defocus monovision ( + 1.25 D add in the nondominant eye), 3) small aperture monovision (1.6 mm pupil in the nondominant eye), and 4) combined small aperture and defocus monovision (1.6 mm pupil and a + 0.75 D add in the nondominant eye). Visual simulations of a small aperture corneal inlay suggest that the device extends DOF as effectively as traditional monovision in photopic light, in both cases at the cost of binocular summation. However, individual factors, such as aperture centration or sensitivity to mesopic conditions should be considered to assure adequate visual outcomes. PMID:25360355

  7. Normal taste acuity and preference in female adolescents with impaired 6-n-propylthiouracil sensitivity.

    PubMed

    Nagai, Ayako; Kubota, Masaru; Sakai, Midori; Higashiyama, Yukie

    2014-01-01

    This study was conducted to determine the relationship between 6-n-propylthiouracil sensitivity and taste characteristics in female students at Nara Women's University. Participants (n=135) were screened for 6-npropylthiouracil sensitivity using a taste test with 0.56 mM 6-n-propylthiouracil solution, and the sensitivity was confirmed by an assay for the bitter-taste receptor gene, TAS2R38. Based on the screening results, 33 6-npropylthiouracil tasters and 21 non-tasters were enrolled. The basic characteristics that are thought to influence taste acuity, including body mass index, saliva volume and serum micronutrient concentrations (iron, zinc and copper), were similar between the two groups. In an analysis using a filter-paper disc method, there were no differences in the acuity for four basic tastes (sweet, salty, sour and bitter) between 6-n-propylthiouracil tasters and non-tasters. In addition, the taste preference for the four basic tastes as measured by a visual analogue scale was also comparable between the two groups. This is the first study to demonstrate that 6-n-propylthiouracil nontasters have taste sensitivity for the four basic tastes similar to that in 6-n-propylthiouracil tasters, at least in female adolescents, as measured by the gustatory test using a filter-paper disc method. PMID:25164453

  8. Intrarectal Amifostine During External Beam Radiation Therapy for Prostate Cancer Produces Significant Improvements in Quality of Life Measured by EPIC Score

    SciTech Connect

    Simone, Nicole L.; Menard, Cynthia; Soule, Benjamin P.; Albert, Paul S.; Guion, Peter; Smith, Sharon; Godette, Denise; Crouse, Nancy S.; Sciuto, Linda C.; Cooley-Zgela, Theresa; Camphausen, Kevin; Coleman, C. Norman; Singh, Anurag K. E-mail: singan@mail.nih.gov

    2008-01-01

    Purpose: To test whether intrarectal amifostine limits symptoms of radiation proctitis, measured by using the Radiation Therapy Oncology Group (RTOG) gastrointestinal (GI) toxicity score and the Expanded Prostate Cancer Index Composite (EPIC) score. Methods and Materials: Patients with localized prostate cancer received amifostine as a rectal suspension 30-45 minutes before daily three-dimensional conformal radiation therapy. The first 18 patients received 1 g of amifostine, and the next 12 patients received 2 g. Toxicity was assessed at baseline, during treatment, and at follow-up visits by using RTOG grading and the EPIC Quality of Life (QoL) 50-item questionnaire. The Bowel Function subset of the bowel domain (EPIC-BF), which targets symptom severity, and the Bowel Bother subset of the bowel domain (EPIC-BB), which assesses QoL, were evaluated and compared with the RTOG GI toxicity score. Results: Median follow-up was 30 months (range, 18-36 months). Overall, EPIC-BF and EPIC-BB scores both tracked closely with the RTOG GI toxicity score. Seven weeks after the start of radiation therapy, the incidence of RTOG Grade 2 toxicity was 33% in the 1-g group (6/18 patients) compared with 0% (0/12 patients) in the 2-g group and trended toward statistical significance (p = 0.06). A significant difference between amifostine groups was observed using the EPIC-BF score at 7 weeks (p = 0.04). A difference in EPIC-BB scores between dose groups was evident at 7 weeks (p = 0.07) and was significant at 12 months (p = 0.04). Conclusions: Higher doses of amifostine produced significant improvements in acute and late bowel QoL (up to 1 year after therapy), measured using the EPIC score.

  9. OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS & HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION

    SciTech Connect

    Alan Black; Arnis Judzis

    2004-10-01

    The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit-fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all major preparations for the high pressure drilling campaign. Baker Hughes encountered difficulties in providing additional pumping capacity before TerraTek's scheduled relocation to another facility, thus the program was delayed further to accommodate the full testing program.

  10. Steam cooking significantly improves in vitro bile acid binding of collard greens, kale, mustard greens, broccoli, green bell pepper, and cabbage.

    PubMed

    Kahlon, Talwinder Singh; Chiu, Mei-Chen M; Chapman, Mary H

    2008-06-01

    Bile acid binding capacity has been related to the cholesterol-lowering potential of foods and food fractions. Lowered recirculation of bile acids results in utilization of cholesterol to synthesize bile acid and reduced fat absorption. Secondary bile acids have been associated with increased risk of cancer. Bile acid binding potential has been related to lowering the risk of heart disease and that of cancer. Previously, we have reported bile acid binding by several uncooked vegetables. However, most vegetables are consumed after cooking. How cooking would influence in vitro bile acid binding of various vegetables was investigated using a mixture of bile acids secreted in human bile under physiological conditions. Eight replicate incubations were conducted for each treatment simulating gastric and intestinal digestion, which included a substrate only, a bile acid mixture only, and 6 with substrate and bile acid mixture. Cholestyramine (a cholesterol-lowering, bile acid binding drug) was the positive control treatment and cellulose was the negative control. Relative to cholestyramine, in vitro bile acid binding on dry matter basis was for the collard greens, kale, and mustard greens, 13%; broccoli, 10%; Brussels sprouts and spinach, 8%; green bell pepper, 7%; and cabbage, 5%. These results point to the significantly different (P < or = .05) health-promoting potential of collard greens = kale = mustard greens > broccoli > Brussels sprouts = spinach = green bell pepper > cabbage as indicated by their bile acid binding on dry matter basis. Steam cooking significantly improved the in vitro bile acid binding of collard greens, kale, mustard greens, broccoli, green bell pepper, and cabbage compared with previously observed bile acid binding values for these vegetables raw (uncooked). Inclusion of steam-cooked collard greens, kale, mustard greens, broccoli, green bell pepper, and cabbage in our daily diet as health-promoting vegetables should be emphasized. These green

  11. Optimization of Deep Drilling Performance--Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

    SciTech Connect

    Alan Black; Arnis Judzis

    2003-10-01

    This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2002 through September 2002. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit--fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. Accomplishments to date include the following: 4Q 2002--Project started; Industry Team was assembled; Kick-off meeting was held at DOE Morgantown; 1Q 2003--Engineering meeting was held at Hughes Christensen, The Woodlands Texas to prepare preliminary plans for development and testing and review equipment needs; Operators started sending information regarding their needs for deep drilling challenges and priorities for large-scale testing experimental matrix; Aramco joined the Industry Team as DEA 148 objectives paralleled the DOE project; 2Q 2003--Engineering and planning for high pressure drilling at TerraTek commenced; 3Q 2003--Continuation of engineering and design work for high pressure drilling at TerraTek; Baker Hughes INTEQ drilling Fluids and Hughes Christensen commence planning for Phase 1 testing--recommendations for bits and fluids.

  12. One-year outcome of intravitreal aflibercept injection for age-related macular degeneration resistant to ranibizumab: rapid morphologic recovery and subsequent visual improvement

    PubMed Central

    Hirakata, Toshiaki; Fujinami, Kaoru; Watanabe, Ken; Sasaki, Mariko; Noda, Toru; Akiyama, Kunihiko

    2016-01-01

    Objective To describe the 1-year efficacy of aflibercept in Japanese patients with age-related macular degeneration (AMD) who were resistant to ranibizumab treatment. Design Retrospective case series. Participants Fourteen consecutive eyes of 14 patients with AMD were enrolled who had no substantial response or developed resistance to intravitreal ranibizumab injections. Methods All patients were subcategorized into one of two subtypes of AMD: seven patients with occult choroidal neovascularization (CNV) and seven with polypoidal choroidal vasculopathy (PCV). Serial intravitreal aflibercept (IVA) injections were administered. Comprehensive ophthalmic examinations, including optical coherence tomography, were conducted at baseline and at follow-up examinations at 1, 3, 6, and 12 months after the initial IVA injection. The best-corrected visual acuity converted to logarithm of the minimum angle of resolution (logMAR) and central macular thickness (CMT) at each follow-up visit were compared with the baseline values. The anatomic response was also assessed with absorption or reduction of fluid in the subretina or subretinal pigment epithelial space. Results The logMAR best-corrected visual acuity improved significantly at 3, 6, and 12 months in the total cohort: at 3 and 6 months in patients with occult CNV and at 3 and 12 months in patients with PCV. The CMT decreased significantly at all follow-up visits in the total cohort as well as in both subtypes, except for the CMT at 6 months in PCV patients. The anatomic improvement was also demonstrated in all cases, and pigment epithelial detachments tended to be resolved more rapidly in patients with PCV than in patients with occult CNV. Conclusion Conversion to IVA was effective in patients with AMD resistant to ranibizumab, showing rapid morphologic improvement. The logMAR visual acuity was raised significantly within 12 months, and the clinical course of visual acuity improvement may differ according to the AMD subtypes

  13. Blunted HPA axis responsiveness to stress in atopic patients is associated with the acuity and severeness of allergic inflammation.

    PubMed

    Buske-Kirschbaum, A; Ebrecht, M; Hellhammer, D H

    2010-11-01

    Previously we could demonstrate attenuated responsiveness of the hypothalamus-pituitary-adrenal (HPA) axis to stress in patients with chronic allergic inflammatory disease (i.e., atopic dermatitis, allergic asthma). The present study was designed to investigate HPA axis function in an acute manifestation of allergy. Patients with seasonal allergic rhinitis (SAR; n = 20) and non-atopic controls (n = 20) were exposed to a standardized laboratory stressor ('Trier Social Stress Test'; TSST). Cortisol responses to the TSST and cortisol awakening responses (CAR) were measured in SAR subjects while suffering from acute symptoms of SAR (pollen season), and during a non-active state of their disease (pollen-free season). To assess the acuity and severity of SAR, eosinophil and basophil numbers and SAR symptomatology were determined. Non-allergic control subjects were examined at identical times during the year. To control for possible sequence effects, a cross-over design was used. SAR patients showed significantly increased symptom severity (t = 9.4; p<.001) as well as eosinophil (F(1,31) = 9.8; p<.01) and basophil (F(1,38) = 6.4; p<.05) numbers during the pollen season when compared to a pollen-free period. When exposed to the TSST, significantly attenuated cortisol responses were found in SAR subjects during acute manifestation of the disease (pollen season) when compared to the pollen-free season (F(16,456) = 1.65; p<.05). In SAR patients, there was a significant negative correlation between symptom severity and the cortisol response to the stressor (r = .53; p<.05). No significant between-group or between-condition differences with respect to the CAR could be determined (all p>.05). These findings support previous data of attenuated HPA axis responsiveness to stress in atopic conditions and further, suggest that HPA axis hyporesponsiveness in atopy may be linked to the severity of the allergic inflammatory process. PMID:20633637

  14. Genipin-structured peptide-polysaccharide nanoparticles with significantly improved resistance to harsh gastrointestinal environments and their potential for oral delivery of polyphenols.

    PubMed

    Hu, Bing; Xie, Minhao; Zhang, Chen; Zeng, Xiaoxiong

    2014-12-24

    Genipin-cross-linked caseinophosphopeptide (CPP)-chitosan (CS) nanoparticles (smaller than 300 nm) showed significantly improved stability and adjustable release profile in the gastrointestinal (GI) tract. Optimal purification of the nanoparticles was established by centrifugation to terminate the cross-linking reaction, which was further confirmed and characterized by FT-IR. Results from transmission electron microscopy (TEM), dynamic light scattering (DLS), and electrophoretic mobility (ζ-potential) measurements revealed that genipin cross-linking significantly prevented the bursting of the CPP-CS nanoparticles in simulated stomach acid and their precipitation under neutral intestinal environment. Pepsin showed little impact on the nanoparticle colloid stability; however, trypsin induced their aggregations. Genipin cross-linking slowed the burst release of (-)-epigallocatechin-3-gallate (EGCG) from the nanoparticles. The EGCG-loaded nanoparticles showed strong cytotoxicity against cancer cells; meanwhile, the net nanoparticles demonstrated high biocompatibility. The findings in the present work provide fundamental information for the rational design of biopolymer nanoparticles as an effective delivery systems for polyphenols. PMID:25479066

  15. Significant Improvement of Antithrombotic Responses to Clopidogrel by Use of a Novel Conjugate as Revealed in an Arterial Model of Thrombosis.

    PubMed

    Zhang, Haoming; Lauver, D Adam; Wang, Hui; Sun, Duxin; Hollenberg, Paul F; Chen, Y Eugene; Osawa, Yoichi; Eitzman, Daniel T

    2016-10-01

    Clopidogrel is a prodrug that requires bioactivation by cytochrome P450 (P450) enzymes to a pharmacologically active metabolite for antiplatelet action. The clinical limitations of clopidogrel are in large part due to its poor pharmacokinetics resulting from inefficient bioactivation by P450s. In this study, we determined the pharmacokinetics and pharmacodynamics of a novel conjugate of clopidogrel, referred to as ClopNPT, in animal models and we evaluated its potential to overcome the limitations of clopidogrel. Results from pharmacokinetic (PK) studies showed that ClopNPT released the active metabolite with a time to maximal plasma concentration of <5 minutes in C57BL/6 mice after either oral or intravenous administration, and plasma concentrations of the active metabolite reached Cmax values of 1242 and 1100 ng/ml after a 10-mg/kg oral dose and a 5-mg/kg intravenous dose, respectively. Furthermore, ClopNPT was highly effective in preventing arterial thrombosis in rabbits and mice after vascular injuries. Formation of occlusive thrombi was prevented by ClopNPT at the 1-mg/kg dose with no significant increase in tongue bleeding time, whereas clopidogrel was ineffective at the same dose. These results suggest that ClopNPT has favorable PK/pharmacodynamic properties that can potentially overcome the attenuated PK properties of clopidogrel and thus significantly improve the efficacy of antiplatelet therapy. PMID:27511819

  16. High-dose electron beam sterilization of soft-tissue grafts maintains significantly improved biomechanical properties compared to standard gamma treatment.

    PubMed

    Hoburg, A; Keshlaf, S; Schmidt, T; Smith, M; Gohs, U; Perka, C; Pruss, A; Scheffler, S

    2015-06-01

    Gy: 0.50 ± 0.34 mm; 34 kGy: 0.26 ± 0.24 mm) and control (0.20 ± 0.18 mm) group that did not differ significantly. Strain difference was not different between either control or study groups (controls: 1.0 ± 0.03; Ebeam 34 kGy 1.04 ± 0.018; Gamma 34 kGy 1.0 ± 0.028; 25 kGy: 1.4 ± 2,0; 34 kGy: 1.1 ± 1.1). The most important result of this study was that ebeam irradiation showed significantly less impairment of the biomechanical properties than gamma irradiation. Considering the results of this study and the improved control of irradiation application with electronic beam, this technique might be a promising alternative in soft-tissue sterilization. PMID:25037592

  17. Significant Improvements in Cognitive Performance Post-Transcranial, Red/Near-Infrared Light-Emitting Diode Treatments in Chronic, Mild Traumatic Brain Injury: Open-Protocol Study

    PubMed Central

    Zafonte, Ross; Krengel, Maxine H.; Martin, Paula I.; Frazier, Judith; Hamblin, Michael R.; Knight, Jeffrey A.; Meehan, William P.; Baker, Errol H.

    2014-01-01

    Abstract This pilot, open-protocol study examined whether scalp application of red and near-infrared (NIR) light-emitting diodes (LED) could improve cognition in patients with chronic, mild traumatic brain injury (mTBI). Application of red/NIR light improves mitochondrial function (especially in hypoxic/compromised cells) promoting increased adenosine triphosphate (ATP) important for cellular metabolism. Nitric oxide is released locally, increasing regional cerebral blood flow. LED therapy is noninvasive, painless, and non-thermal (cleared by the United States Food and Drug Administration [FDA], an insignificant risk device). Eleven chronic, mTBI participants (26–62 years of age, 6 males) with nonpenetrating brain injury and persistent cognitive dysfunction were treated for 18 outpatient sessions (Monday, Wednesday, Friday, for 6 weeks), starting at 10 months to 8 years post- mTBI (motor vehicle accident [MVA] or sports-related; and one participant, improvised explosive device [IED] blast injury). Four had a history of multiple concussions. Each LED cluster head (5.35 cm diameter, 500 mW, 22.2 mW/cm2) was applied for 10 min to each of 11 scalp placements (13 J/cm2). LEDs were placed on the midline from front-to-back hairline; and bilaterally on frontal, parietal, and temporal areas. Neuropsychological testing was performed pre-LED, and at 1 week, and 1 and 2 months after the 18th treatment. A significant linear trend was observed for the effect of LED treatment over time for the Stroop test for Executive Function, Trial 3 inhibition (p=0.004); Stroop, Trial 4 inhibition switching (p=0.003); California Verbal Learning Test (CVLT)-II, Total Trials 1–5 (p=0.003); and CVLT-II, Long Delay Free Recall (p=0.006). Participants reported improved sleep, and fewer post-traumatic stress disorder (PTSD) symptoms, if present. Participants and family reported better ability to perform social, interpersonal, and occupational functions. These open-protocol data suggest

  18. Significant improvements in cognitive performance post-transcranial, red/near-infrared light-emitting diode treatments in chronic, mild traumatic brain injury: open-protocol study.

    PubMed

    Naeser, Margaret A; Zafonte, Ross; Krengel, Maxine H; Martin, Paula I; Frazier, Judith; Hamblin, Michael R; Knight, Jeffrey A; Meehan, William P; Baker, Errol H

    2014-06-01

    This pilot, open-protocol study examined whether scalp application of red and near-infrared (NIR) light-emitting diodes (LED) could improve cognition in patients with chronic, mild traumatic brain injury (mTBI). Application of red/NIR light improves mitochondrial function (especially in hypoxic/compromised cells) promoting increased adenosine triphosphate (ATP) important for cellular metabolism. Nitric oxide is released locally, increasing regional cerebral blood flow. LED therapy is noninvasive, painless, and non-thermal (cleared by the United States Food and Drug Administration [FDA], an insignificant risk device). Eleven chronic, mTBI participants (26-62 years of age, 6 males) with nonpenetrating brain injury and persistent cognitive dysfunction were treated for 18 outpatient sessions (Monday, Wednesday, Friday, for 6 weeks), starting at 10 months to 8 years post- mTBI (motor vehicle accident [MVA] or sports-related; and one participant, improvised explosive device [IED] blast injury). Four had a history of multiple concussions. Each LED cluster head (5.35 cm diameter, 500 mW, 22.2 mW/cm(2)) was applied for 10 min to each of 11 scalp placements (13 J/cm(2)). LEDs were placed on the midline from front-to-back hairline; and bilaterally on frontal, parietal, and temporal areas. Neuropsychological testing was performed pre-LED, and at 1 week, and 1 and 2 months after the 18th treatment. A significant linear trend was observed for the effect of LED treatment over time for the Stroop test for Executive Function, Trial 3 inhibition (p=0.004); Stroop, Trial 4 inhibition switching (p=0.003); California Verbal Learning Test (CVLT)-II, Total Trials 1-5 (p=0.003); and CVLT-II, Long Delay Free Recall (p=0.006). Participants reported improved sleep, and fewer post-traumatic stress disorder (PTSD) symptoms, if present. Participants and family reported better ability to perform social, interpersonal, and occupational functions. These open-protocol data suggest that placebo

  19. Omega-conotoxin MVIIC attenuates neuronal apoptosis in vitro and improves significant recovery after spinal cord injury in vivo in rats

    PubMed Central

    Oliveira, Karen M; Lavor, Mário Sérgio L; Silva, Carla Maria O; Fukushima, Fabíola B; Rosado, Isabel R; Silva, Juneo F; Martins, Bernardo C; Guimarães, Laís B; Gomez, Marcus Vinícius; Melo, Marília M; Melo, Eliane G

    2014-01-01

    Excessive accumulation of intracellular calcium is the most critical step after spinal cord injury (SCI). Reducing the calcium influx should result in a better recovery from SCI. Calcium channel blockers have been shown a great potential in reducing brain and spinal cord injury. In this study, we first tested the neuroprotective effect of MVIIC on slices of spinal cord subjected to ischemia evaluating cell death and caspase-3 activation. Thereafter, we evaluated the efficacy of MVIIC in ameliorating damage following SCI in rats, for the first time in vivo. The spinal cord slices subjected a pretreatment with MVIIC showed a cell protection with a reduction of dead cells in 24.34% and of caspase-3-specific protease activation. In the in vivo experiment, Wistar rats were subjected to extradural compression of the spinal cord at the T12 vertebral level using a weigh of 70 g/cm, following intralesional treatment with either placebo or MVIIC in different doses (15, 30 and 60 pmol) five minutes after injury. Behavioral testing of hindlimb function was done using the Basso Beattie Bresnahan locomotor rating scale, and revealed significant recovery with 15 pmol (G15) compared to other trauma groups. Also, histological bladder structural revealed significant outcome in G15, with no morphological alterations, and anti-NeuN and TUNEL staining showed that G15 provided neuron preservation and indicated that this group had fewer neuron cell death, similar to sham. These results showed the neuroprotective effects of MVIIC in in vitro and in vivo model of SCI with neuronal integrity, bladder and behavioral improvements. PMID:25120731

  20. Grating visual acuity testing as a means of psychophysical assessment of progressive addition lenses.

    PubMed

    Sullivan, C M; Fowler, C W

    1989-09-01

    Progressive addition lenses (PAL's) are subject to objectionable astigmatism due to the aspheric nature of their anterior surfaces. Optico-physical assessment of PAL's is commonly undertaken but these measures should be related to the psychophysical responses of patients whilst wearing PAL's. A technique previously used for the psychophysical assessment of contact lenses and spectacle lenses is adapted and demonstrated for the measurement of grating visual acuity (VA) through the aspheric portion of PAL's. The apparatus encompasses an astronomical telescope with magnifying power of unity designed to stabilize accommodation. This paper considers the astigmatism present with three different PAL designs along a horizontal section cutting orthogonally through the umbilical line of each lens. VA was measured, using high contrast vertical and horizontal gratings, along the same horizontal sections of the PAL's studied. A reduction in VA was noted with an increase in the angle of eccentricity from the umbilical line. PMID:2797709

  1. How olfactory acuity affects the sensory assessment of boar fat: a proposal for quantification.

    PubMed

    Trautmann, Johanna; Gertheiss, Jan; Wicke, Michael; Mörlein, Daniel

    2014-10-01

    Due to animal welfare concerns the production of entire male pigs is one viable alternative to surgical castration. Elevated levels of boar taint may, however, impair consumer acceptance. Due to the lack of technical methods, control of boar taint is currently done using sensory quality control. While the need for control measures with respect to boar taint has been clearly stated in EU legislation, no specific requirements for selecting assessors have yet been documented. This study proposes tests for the psychophysical evaluation of olfactory acuity to key volatiles contributing to boar taint. Odor detection thresholds for androstenone and skatole are assessed as well as the subject's ability to identify odorants at various levels through easy-to-use paper smell strips. Subsequently, fat samples are rated by the assessors, and the accuracy of boar taint evaluation is studied. Considerable variation of olfactory performance is observed demonstrating the need for objective criteria to select assessors. PMID:24976560

  2. Preclinical metrics to predict through-focus visual acuity for pseudophakic patients

    PubMed Central

    Alarcon, Aixa; Canovas, Carmen; Rosen, Robert; Weeber, Henk; Tsai, Linda; Hileman, Kendra; Piers, Patricia

    2016-01-01

    This study compares the clinical through-focus visual acuity (VA) in patients implanted with different intraocular lens (IOL) to optical bench testing of the same IOLs to evaluate the suitability of optical metrics of predicting clinical VA. Modulation transfer function and phase transfer function for different spatial frequencies and US Air Force pictures were measured using an optical bench for two monofocal IOLs, three multifocal IOLs and an extended range of vision IOL. Four preclinical metrics were calculated and compared to the clinical through-focus VA collected in three different clinical studies (243 patients in total). All metrics were well correlated (R2≥0.89) with clinical data and may be suitable for predicting through-focus VA in pseudophakic eyes. PMID:27231628

  3. The Amelioration of Olfactory Acuity upon Sexual Maturation Might Affect Food Preferences

    PubMed Central

    Bignetti, Enrico; Sinesio, Fiorella; Aiello, Gaetano L.; Cannella, Carlo

    2009-01-01

    Upon sexual maturation, olfactory acuity in women ameliorates and starts oscillating across the cycle. During ovulation, mean olfactory threshold is 30 times lower than during bleeding. Interestingly, menstruated women undergo maleodorant trimethylaminuria. We argued that olfactory amelioration during ovulation might concur to a mating strategy, whereas olfactory impairment during bleeding might protect women against self-refusal. Testosterone and its 17β-estradiol derivative might be responsible for the synchronization of these menstrual events. Furthermore, we posed the question whether olfactory detection amelioration upon sexual maturation might provoke a change in food preferences, for instance a reduction in fish consumption. A preliminary survey in Italy provided encouraging results: 15-44 year-old women have lower fish consumption than 3-14 year-old girls. Surprisingly, men exhibited the same behaviour, so new olfactory tests as well as testosterone measurements are under way. PMID:22253964

  4. Very low amount of TiO2 on N-doped carbon nanotubes significantly improves oxygen reduction activity and stability of supported Pt nanoparticles.

    PubMed

    Zhao, Anqi; Masa, Justus; Xia, Wei

    2015-04-28

    Electrochemical corrosion is a major problem for carbon materials used in electrocatalysis. Highly dispersed TiO2 was deposited on O-functionalized and N-doped carbon nanotubes by chemical vapour deposition to tackle the carbon corrosion problem. Very low Ti loadings of about 1 wt% were applied to minimize the negative influence of TiO2 as a semiconductor on the high conductivity of carbon materials. Both N doping and TiO2 coating facilitate strong metal-support interactions and favour the formation of small Pt particles. N doping improved the intrinsic catalytic activity of the carbon support and enhanced the conductivity due to the removal of surface oxygen groups, while the negative effect of TiO2 on conductivity is counterbalanced by its promoting effect on metal-support interactions leading to enhanced overall catalytic performance. Pt/TiO2/NCNTs showed the highest ORR activity, and significantly outperformed Pt/NCNTs in electrochemical stability tests. PMID:25811122

  5. Initiation of insulin aspart to Indian subjects on OADs show significant improvement in glycaemic outcomes: the A1chieve observational study.

    PubMed

    Rao, P V; Bhattacharyya, A; Sahay, R K

    2013-01-01

    The prevalence of diabetes is increasing worldwide and India stands second next only to china. The management of diabetes in real life settings needs to be evaluated for deriving better management practices. A1chieve observational study evaluated the use of modern insulin in real life settings. This was a 24-week, international, prospective, multicenter, non-interventional, observational study of people with type 2 diabetes. India recruited with 20,554 subjects and a total of 1815 patients were enrolled to receive insulin aspart as bolus insulin therapy of whom 1450 (79.9%) were insulin naïve and 365 (20.1%) were insulin users. At the end of 24 weeks, only one SAE was reported in this study and overall hypoglycemia events per patient year decreased from 2.49 (348 episodes) to 0.17 (20 episodes). There were no major hypoglycemic episodes reported in either insulin naive or insulin treated subjects. There was a significant improvement in the HbA(1c) values from the baseline in both insulin naive and insulin users. The mean HbA(1c) value was reduced from 9.5 to 7.4 (p < 0.001) for insulin naïve subjects and from 9.2 to 7.7 (p < 0.001) in insulin experienced subjects. Fasting plasma glucose values decreased by 70 mg/dL and 50 mg/dL in insulin naive and insulin experienced, respectively and the difference from baseline was statistically significant (P < 0.001). The post prandial glucose value was also significantly (p < 0.001) reduced by 105 mg/dL for insulin naïve subjects and 55 mg/dL for insulin experienced subjects. The composite end point was achieved by 46.6% of insulin naive and 38.1% of insulin-experienced subjects. The study concluded with good HbA(1c) reduction along with lower incidence of hypoglycemia and better health related quality of life outcomes in both in insulin naive and insulin experienced subjects who used insulin aspart as bolus insulin treatment. PMID:24482983

  6. Contrast visual acuity in patients with retinitis pigmentosa assessed by a contrast sensitivity tester

    PubMed Central

    Oishi, Maho; Nakamura, Hajime; Hangai, Masanori; Oishi, Akio; Otani, Atsushi; Yoshimura, Nagahisa

    2012-01-01

    Purpose: To assess contrast visual acuity (CVA) in patients with retinitis pigmentosa (RP) and compare the result with standard visual acuity (VA), retinal thickness, status of inner segment/outer segment junction, and central visual field. Materials and Methods: Thirty-nine eyes of 39 patients with RP and 39 eyes of 39 healthy individuals were studied. To see the difference in CVA between RP patients and normal controls, only subjects with standard VA of 1.0 (20/20) or better were included. This was a cross-sectional study. CVA in various light conditions was measured with CAT-2000 and was compared between patients and controls. CVA of patients was further analyzed for association with other parameters including foveal retinal thickness, outer nuclear layer thickness, the status of inner segment/outer segment junction measured with optical coherence tomography (OCT), and visual field mean deviation (MD) measured with Humphrey field analyzer 10-2 program. Results: CVA impairment was evident in RP patients compared to controls (P < 0.01, in all measurement conditions). Multivariate analysis showed association of logarithm of the minimum angle of resolution (logMAR) with CVAs in several conditions. None of the OCT measurements was associated with CVA. When patients were divided into three groups based on MD, the most advanced group (MD worse than or equal to –20 dB) showed impairment of mesopic CVA (P < 0.05, under mesopic condition of 100% without glare, with glare, and 25% without glare). Conclusion: CVA impairment was confirmed in RP patients, especially in advanced cases. CVA measured with CAT-2000 may be a useful tool for assessing foveal function in RP patients. PMID:23202395

  7. Significant Treasures.

    ERIC Educational Resources Information Center

    Andrews, Ian A.

    1999-01-01

    Provides a crossword puzzle with an answer key corresponding to the book entitled "Significant Treasures/Tresors Parlants" that is filled with color and black-and-white prints of paintings and artifacts from 131 museums and art galleries as a sampling of the 2,200 such Canadian institutions. (CMK)

  8. Significant Improvement of Puncture Accuracy and Fluoroscopy Reduction in Percutaneous Transforaminal Endoscopic Discectomy With Novel Lumbar Location System: Preliminary Report of Prospective Hello Study.

    PubMed

    Fan, Guoxin; Guan, Xiaofei; Zhang, Hailong; Wu, Xinbo; Gu, Xin; Gu, Guangfei; Fan, Yunshan; He, Shisheng

    2015-12-01

    Prospective nonrandomized control study.The study aimed to investigate the implication of the HE's Lumbar LOcation (HELLO) system in improving the puncture accuracy and reducing fluoroscopy in percutaneous transforaminal endoscopic discectomy (PTED).Percutaneous transforaminal endoscopic discectomy is one of the most popular minimally invasive spine surgeries that heavily depend on repeated fluoroscopy. Increased fluoroscopy will induce higher radiation exposure to surgeons and patients. Accurate puncture in PTED can be achieved by accurate preoperative location and definite trajectory.The HELLO system mainly consists of self-made surface locator and puncture-assisted device. The surface locator was used to identify the exact puncture target and the puncture-assisted device was used to optimize the puncture trajectory. Patients who had single L4/5 or L5/S1 lumbar intervertebral disc herniation and underwent PTED were included the study. Patients receiving the HELLO system were assigned in Group A, and those taking conventional method were assigned in Group B. Study primary endpoint was puncture times and fluoroscopic times, and the secondary endpoint was location time and operation time.A total of 62 patients who received PTED were included in this study. The average age was 45.35 ± 8.70 years in Group A and 46.61 ± 7.84 years in Group B (P = 0.552). There were no significant differences in gender, body mass index, conservative time, and surgical segment between the 2 groups (P > 0.05). The puncture times were 1.19 ± 0.48 in Group A and 6.03 ± 1.87 in Group B (P < 0.001). The fluoroscopic times were 14.03 ± 2.54 in Group A and 25.19 ± 4.28 in Group B (P < 0.001). The preoperative location time was 4.67 ± 1.41 minutes in Group A and 6.98 ± 0.94 minutes in Group B (P < 0.001). The operation time was 79.42 ± 10.15 minutes in Group A and 89.65 ± 14.06 minutes in Group B (P = 0.002). The

  9. An Evidence-Based Education Program for Adults about Child Sexual Abuse ("Prevent It!") That Significantly Improves Attitudes, Knowledge, and Behavior.

    PubMed

    Martin, Erin K; Silverstone, Peter H

    2016-01-01

    Here we describe the development of an evidence-based education program for adults about childhood sexual abuse (CSA), called Prevent It! Uniquely, the primary goal of this program was to change the behavior of participants, as well as to increase knowledge about CSA and positive attitudes toward it. A comprehensive review shows no previous similar approach. The program includes a detailed manual to allow standardized administration by trained facilitators, as well as multiple video segments from CSA survivors and professionals. A total of 23 program workshops were run, with 366 adults participating. Of these, 312 (85%) agreed to take part in the study. All completed baseline ratings prior to the program and 195 (63% of study sample) completed follow-up assessments at 3-months. There were no significant differences between the demographic make-up of the baseline group and the follow-up group. Assessments included demographic data, knowledge, attitudes, and several measures of behavior (our primary outcome variable). Behavioral questions asked individuals to select behaviors used in the previous 3-months from a list of options. Questions also included asking "how many times in the previous 3-months" have you "talked about healthy sexual development or Child sexual abuse (CSA) with a child you know"; "suspected a child was sexually abused"; "taken steps to protect a child"; or "reported suspected sexual abuse to police or child welfare"? The majority of attendees were women, with the commonest age group being between 30 and 39 years old. Approximately 33% had experienced CSA themselves. At 3-month follow-up there were highly statistically significant improvements in several aspects of behavior and knowledge, and attitudes regarding CSA. For example, the number of subjects actively looking for evidence of CSA increased from 46% at baseline to 81% at follow-up, while the number of subjects who actively took steps to protect children increased from 25% at baseline to 48

  10. An Evidence-Based Education Program for Adults about Child Sexual Abuse (“Prevent It!”) That Significantly Improves Attitudes, Knowledge, and Behavior

    PubMed Central

    Martin, Erin K.; Silverstone, Peter H.

    2016-01-01

    Here we describe the development of an evidence-based education program for adults about childhood sexual abuse (CSA), called Prevent It! Uniquely, the primary goal of this program was to change the behavior of participants, as well as to increase knowledge about CSA and positive attitudes toward it. A comprehensive review shows no previous similar approach. The program includes a detailed manual to allow standardized administration by trained facilitators, as well as multiple video segments from CSA survivors and professionals. A total of 23 program workshops were run, with 366 adults participating. Of these, 312 (85%) agreed to take part in the study. All completed baseline ratings prior to the program and 195 (63% of study sample) completed follow-up assessments at 3-months. There were no significant differences between the demographic make-up of the baseline group and the follow-up group. Assessments included demographic data, knowledge, attitudes, and several measures of behavior (our primary outcome variable). Behavioral questions asked individuals to select behaviors used in the previous 3-months from a list of options. Questions also included asking “how many times in the previous 3-months” have you “talked about healthy sexual development or Child sexual abuse (CSA) with a child you know”; “suspected a child was sexually abused”; “taken steps to protect a child”; or “reported suspected sexual abuse to police or child welfare”? The majority of attendees were women, with the commonest age group being between 30 and 39 years old. Approximately 33% had experienced CSA themselves. At 3-month follow-up there were highly statistically significant improvements in several aspects of behavior and knowledge, and attitudes regarding CSA. For example, the number of subjects actively looking for evidence of CSA increased from 46% at baseline to 81% at follow-up, while the number of subjects who actively took steps to protect children increased from

  11. Derivation of Primordial germ cells from Human Embryonic and Induced Pluripotent Stem Cells is significantly improved by co-culture with human fetal gonadal cells

    PubMed Central

    Park, Tae Sub; Galic, Zoran; Conway, Anne E.; Lindgren, Anne; Van Handel, Benjamin J.; Magnusson, Mattias; Richter, Laura; Teitell, Michael A.; Mikkola, Hanna K.A; Lowry, William E.; Plath, Kathrin; Clark, Amander T

    2012-01-01

    The derivation of germ cells from human embryonic stem cells (hESCs) or human induced pluripotent stem (hIPS) cells represents a desirable experimental model and potential strategy for treating infertility. In the current study we developed a triple biomarker assay for identifying and isolating human primordial germ cells (PGCs) by first evaluating human PGC formation during the first trimester in vivo. Next, we applied this technology to characterizing in vitro derived PGCs (iPGCs) from pluripotent cells. Our results show that co-differentiation of hESCs on human fetal gonadal stromal cells significantly improves the efficiency of generating iPGCs. Furthermore, the efficiency was comparable between various pluripotent cell lines regardless of origin from the inner cell mass of human blastocysts (hESCs), or reprogramming of human skin fibroblasts (hIPS). In order to better characterize the iPGCs we performed Real time PCR, microarray and bisulfite sequencing. Our results show that iPGCs at day 7 of differentiation are transcriptionally distinct from the somatic cells, expressing genes associated with pluripotency and germ cell development while repressing genes associated with somatic differentiation (specifically multiple HOX genes). Using bisulfite sequencing, we show that iPGCs initiate imprint erasure from differentially methylated imprinted regions by day 7 of differentiation. However, iPGCs derived from hIPS cells do not initiate imprint erasure as efficiently. In conclusion, our results indicate that triple positive iPGCs derived from pluripotent cells differentiated on hFGS cells correspond to committed first trimester germ cells (before 9 weeks) that have initiated the process of imprint erasure. PMID:19350678

  12. Adding blood to agitated saline significantly improves detection of right-to-left shunt by contrast-transcranial color-coded duplex sonography.

    PubMed

    Gentile, Mauro; De Vito, Alessandro; Azzini, Cristiano; Tamborino, Carmine; Casetta, Ilaria

    2014-11-01

    Contrast-transcranial Doppler and contrast-transcranial color-coded duplex sonography (c-TCCD) have been reported to have high sensitivity in detecting patent foramen ovale as compared with transesophageal echocardiography. An international consensus meeting (Jauss and Zanette 2000) recommended that the contrast agent for right-to left-shunt (RLS) detection using contrast-transcranial Doppler be prepared by mixing 9 mL of isotonic saline solution and 1 mL of air. The aim of our study was to determine whether adding blood to the contrast agent results in improved detection of RLS. We enrolled all consecutive patients admitted to our neurosonology laboratory for RLS diagnosis. For each patient, we performed c-TCCD both at rest and during the Valsalva maneuver using two different contrast agents: ANSs (1 mL of air mixed with 9 mL of normal saline) and ANSHBs (1 mL of air mixed with 8 mL of normal saline and 1 mL of the patient's blood). To classify RLS, we used a four-level visual categorization: (i) no occurrence of micro-embolic signals; (ii) grade I, 1-10 signals; (iii) grade II, >10 signals but no curtain; grade III, curtain pattern. We included 80 patients, 33 men and 47 women. RLS was detected in 18.8% at rest and in 35% during the Valsalva maneuver using ANSs, and in 31.3% and in 46.3% using ANSHBs, respectively (p < 0.0001). There was a statistically significant increase in the number of micro-embolic signals with the use of ANSHBs. The use of blood mixed with saline solution and air as a c-TCCD contrast agent produced an increase in positive tests and a higher grade of RLS compared with normal saline and air alone, either with or without the Valsalva maneuver. PMID:25220269

  13. Pediatric emergency department overcrowding: electronic medical record for identification of frequent, lower acuity visitors. Can we effectively identify patients for enhanced resource utilization?

    PubMed

    Simon, Harold K; Hirsh, Daniel A; Rogers, Alexander J; Massey, Robert; Deguzman, Michael A

    2009-04-01

    disproportionately utilized the ED more than six times (maximum 28), representing 0.7% of patients and 3.6% of visits (8.6 visit/patient, 11 visits/day, p < 0.001). While representing < 2% of patients, frequent lower acuity utilizers of ED services accounted for nearly 10% of all visits (30/day). Low acuity patients may require only limited additional marginal resources for their individual care. However, in aggregate, inefficiencies occur, especially when systems reach capacity constraints, at which point these patients utilize limited resources (manpower and space) that could more effectively be directed toward the more acutely ill and injured patients. Therefore, identification of these patients utilizing the electronic medical record will allow for targeted interventions of this subgroup to improve future resource allocation. PMID:18657929

  14. The Influence of Auditory Acuity on Acoustic Variability and the Use of Motor Equivalence during Adaptation to a Perturbation

    ERIC Educational Resources Information Center

    Brunner, Jana; Ghosh, Satrajit; Hoole, Philip; Matthies, Melanie; Tiede, Mark; Perkell, Joseph

    2011-01-01

    Purpose: The aim of this study was to relate speakers' auditory acuity for the sibilant contrast, their use of motor equivalent trading relationships in producing the sibilant /[esh]/, and their produced acoustic distance between the sibilants /s/ and /[esh]/. Specifically, the study tested the hypotheses that during adaptation to a perturbation…

  15. Brief Report: The Relationship between Visual Acuity, the Embedded Figures Test and Systemizing in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Brosnan, Mark J.; Gwilliam, Lucy R.; Walker, Ian

    2012-01-01

    Enhanced performance upon the Embedded Figures Test (EFT) in individuals with autism spectrum disorder (ASD) has informed psychological theories of the non-social aspects that characterise ASD. The Extreme Male Brain theory of autism proposes that enhanced visual acuity underpins greater attention to detail (assessed by the EFT) which is a…

  16. Visual Acuity of Youths 12-17 Years, United States. Vital and Health Statistics, Series 11, No. 127.

    ERIC Educational Resources Information Center

    Roberts, Jean; Slaby, David

    Presented are the findings of a national health examination survey of uncorrected and corrected monocular and binocular visual acuity of 7,514 noninstitutionalized youth 12 to 17 years of age analyzed with respect to age, sex, race, geographic region, size of place of residence, and annual family income. Among findings reported are that 70 0/0 of…

  17. Proprioceptive acuity predicts muscle co-contraction of the tibialis anterior and gastrocnemius medialis in older adults' dynamic postural control.

    PubMed

    Craig, C E; Goble, D J; Doumas, M

    2016-05-13

    Older adults use a different muscle strategy to cope with postural instability, in which they 'co-contract' the muscles around the ankle joint. It has been suggested that this is a compensatory response to age-related proprioceptive decline however this view has never been assessed directly. The current study investigated the association between proprioceptive acuity and muscle co-contraction in older adults. We compared muscle activity, by recording surface electromyography (EMG) from the bilateral tibialis anterior (TA) and gastrocnemius medialis (GM) muscles, in young (aged 18-34) and older adults (aged 65-82) during postural assessment on a fixed and sway-referenced surface at age-equivalent levels of sway. We performed correlations between muscle activity and proprioceptive acuity, which was assessed using an active contralateral matching task. Despite successfully inducing similar levels of sway in the two age groups, older adults still showed higher muscle co-contraction. A stepwise regression analysis showed that proprioceptive acuity measured using variable error was the best predictor of muscle co-contraction in older adults. However, despite suggestions from previous research, proprioceptive error and muscle co-contraction were negatively correlated in older adults, suggesting that better proprioceptive acuity predicts more co-contraction. Overall, these results suggest that although muscle co-contraction may be an age-specific strategy used by older adults, it is not to compensate for age-related proprioceptive deficits. PMID:26905952

  18. New Evidence on Causal Relationship between Approximate Number System (ANS) Acuity and Arithmetic Ability in Elementary-School Students: A Longitudinal Cross-Lagged Analysis

    PubMed Central

    He, Yunfeng; Zhou, Xinlin; Shi, Dexin; Song, Hairong; Zhang, Hui; Shi, Jiannong

    2016-01-01

    Approximate number system (ANS) acuity and mathematical ability have been found to be closely associated in recent studies. However, whether and how these two measures are causally related still remain less addressed. There are two hypotheses about the possible causal relationship: ANS acuity influences mathematical performances, or access to math education sharpens ANS acuity. Evidences in support of both hypotheses have been reported, but these two hypotheses have never been tested simultaneously. Therefore, questions still remain whether only one-direction or reciprocal causal relationships existed in the association. In this work, we provided a new evidence on the causal relationship between ANS acuity and arithmetic ability. ANS acuity and mathematical ability of elementary-school students were measured sequentially at three time points within one year, and all possible causal directions were evaluated simultaneously using cross-lagged regression analysis. The results show that ANS acuity influences later arithmetic ability while the reverse causal direction was not supported. Our finding adds a strong evidence to the causal association between ANS acuity and mathematical ability, and also has important implications for educational intervention designed to train ANS acuity and thereby promote mathematical ability. PMID:27462291

  19. New Evidence on Causal Relationship between Approximate Number System (ANS) Acuity and Arithmetic Ability in Elementary-School Students: A Longitudinal Cross-Lagged Analysis.

    PubMed

    He, Yunfeng; Zhou, Xinlin; Shi, Dexin; Song, Hairong; Zhang, Hui; Shi, Jiannong

    2016-01-01

    Approximate number system (ANS) acuity and mathematical ability have been found to be closely associated in recent studies. However, whether and how these two measures are causally related still remain less addressed. There are two hypotheses about the possible causal relationship: ANS acuity influences mathematical performances, or access to math education sharpens ANS acuity. Evidences in support of both hypotheses have been reported, but these two hypotheses have never been tested simultaneously. Therefore, questions still remain whether only one-direction or reciprocal causal relationships existed in the association. In this work, we provided a new evidence on the causal relationship between ANS acuity and arithmetic ability. ANS acuity and mathematical ability of elementary-school students were measured sequentially at three time points within one year, and all possible causal directions were evaluated simultaneously using cross-lagged regression analysis. The results show that ANS acuity influences later arithmetic ability while the reverse causal direction was not supported. Our finding adds a strong evidence to the causal association between ANS acuity and mathematical ability, and also has important implications for educational intervention designed to train ANS acuity and thereby promote mathematical ability. PMID:27462291

  20. Wound center facility billing: A retrospective analysis of time, wound size, and acuity scoring for determining facility level of service.

    PubMed

    Fife, Caroline E; Walker, David; Farrow, Wade; Otto, Gordon

    2007-01-01

    Outpatient wound center facility reimbursement for Medicare beneficiaries can be a challenge to determine and obtain. To compare methods of calculating facility service levels for outpatient wound centers and to demonstrate the advantages of an acuity-based billing system (one that incorporates components of facility work that is non-reimbursable by procedure codes and that represents an activity-based costing approach to medical billing), a retrospective study of 5,098 patient encounters contained in a wound care-specific electronic medical record database was conducted. Approximately 500 patient visits to the outpatient wound center of a Texas regional hospital between April 2003 and November 2004 were categorized by service level in documentation and facility management software. Visits previously billed using a time-based system were compared to the Centers for Medicare and Medicaid Services' proposed three-tiered wound size-based system. The time-based system also was compared to an acuity-based scoring system. The Pearson correlation coefficient between billed level of service by time and estimated level of service by acuity was 0.442 and the majority of follow-up visits were billed as Level 3 and above (on a time level of 1 to 5) , confirming that time is not a surrogate for actual work performed. Wound size also was found to be unrelated to service level (Pearson correlation = 0.017) and 97% of wound areas were < 100 cm2. The acuity-based scoring system produced a near-normal distribution of results, producing more mid-range billings than extremes; no other method produced this distribution. Hospital-based outpatient wound centers should develop, review, and refine acuity score-based models on which to determine billed level of service. PMID:17264354

  1. MRI-Guided 3D Optimization Significantly Improves DVH Parameters of Pulsed-Dose-Rate Brachytherapy in Locally Advanced Cervical Cancer

    SciTech Connect

    Lindegaard, Jacob C. Tanderup, Kari; Nielsen, Soren Kynde; Haack, Soren; Gelineck, John

    2008-07-01

    {sub 90} was 91 {+-} 8 Gy{sub {alpha}}{sub /{beta}}{sub 10} and D{sub 100} was 76 {+-} 5 Gy{sub {alpha}}{sub /{beta}}{sub 10}. The minimal dose to 2 cm{sup 3} for the bladder, rectum, and sigmoid was 73 {+-} 6, 67 {+-} 6, and 69 {+-} 6 Gy{sub {alpha}}{sub /{beta}}{sub 3}, respectively. Conclusion: The results of our study have shown that magnetic resonance imaging-guided optimization of PDR-BT for locally advanced cervical cancer significantly improved the dose-volume histogram parameters.

  2. The Significance of Emotions and Professional Relations for Accommodating a Web-Based Ulcer Record and Improving Home-Based Care

    PubMed Central

    Ekeland, Anne G.

    2015-01-01

    Evidence of technological performance, medical improvements and economic effectiveness is generally considered sufficient for judging advances in healthcare. In this paper, I aim to add knowledge about the ways human emotions and professional relations play roles in the processes of accommodating new technologies for quality improvements. A newly-implemented, web-based ulcer record service for patients with chronic skin ulcers constitutes the case. After one year, only a few home care nurses were using the service, interacting with a specialist team. The result was disappointing, but the few users were enthusiastic. An explorative, qualitative study was initiated to understand the users, the processes that accounted for use and how improvements were enacted. In the paper, I expose the emotional aspects of the record accommodation by analyzing the ways emotions were translated in the process and how they influenced the improvements. I contend that use came about through a heterogeneous assemblage of ethical engagement and compassionate emotions stemming from frustration, combined with technological affordances and relations between different professionals. Certain aspects of the improvements are exposed. These are discussed as: (1) reconciliations between the medical facts and rational judgments, on one side, and the emotional and subjective values for judging quality, on the other; and (2) mediation between standardized and personalized care. The healing of ulcers was combined with a sense of purpose and wellbeing to validate improvements. Emotions were strongly involved, and the power of evaluative emotions and professional relations should be further explored to add to the understanding of innovation processes and to validate quality improvements. PMID:27417745

  3. Adaptation of the Central Retina for High Acuity Vision: Cones, the Fovea and the Avascular Zone

    PubMed Central

    Provis, Jan M; Dubis, Adam M; Maddess, Ted; Carroll, Joseph

    2013-01-01

    Presence of a fovea centralis is directly linked to molecular specification of an avascular area in central retina, before the fovea (or `pit') begins to form. Modeling suggests that mechanical forces, generated within the eye, initiate formation of a pit within the avascular area, and its later remodeling in the postnatal period. Within the avascular area the retina is dominated by `midget' circuitry, in which signals are transferred from a single cone to a single bipolar cell, then a single ganglion cell. Thus in inner, central retina there are relatively few lateral connections between neurons. This renders the region adaptable to tangential forces, that translocate of ganglion cells laterally / centrifugally, to form the fovea. Optical coherence tomography enables live imaging of the retina, and shows that there is greater variation in the morphology of foveae in humans than previously thought. This variation is associated with differences in size of the avascular area and appears to be genetically based, but can be modified by environmental factors, including prematurity. Even when the fovea is absent (foveal hypoplasia), cones in central retina adopt an elongated and narrow morphology, enabling them to pack more densely to increase the sampling rate, and to act as more effective waveguides. Given these findings, what then is the adaptive advantage of a fovea? We suggest that the advantages of having a pit in central retina are relatively few, and minor, but together work to enhance acuity. PMID:23500068

  4. Determination of the foveal cone spacing by ocular speckle interferometry: limiting factors and acuity predictions.

    PubMed

    Marcos, S; Navarro, R

    1997-04-01

    We have developed a high-resolution imaging technique, based on speckle interferometry, for the objective determination of the cone spacing in the living human fovea. The spatial resolution attained with this technique is theoretically diffraction limited by the pupil size. However, the highest frequency that we measure varies greatly among subjects, especially for fully dilated pupils. We have conducted several experiments (determination of the cutoff frequency of ocular speckle interferometry, the double-pass modulation transfer function, and the Stiles-Crawford effect) that indicate that, as expected, the resolution is not limited by the incoherent modulation transfer function. We found, though, a high correlation between the cutoff frequency and the width of the eye's Stiles-Crawford function. This implies that the resolution depends on the structural properties of the cone mosaic itself. In addition, we have compared the Nyquist frequency of the cone mosaic, determined objectively by our technique, with the grating visual acuity measured in the same eyes at the same foveal eccentricities. For our subjects, visual resolution nearly matches the Nyquist frequency within the fovea, except at the foveal center, where the optical transfer function of the eye attenuates the contrast of frequencies close to the Nyquist limit to a value below threshold. PMID:9088086

  5. [Laser pointers are not toys; eye injury with permanent loss of visual acuity].

    PubMed

    Keunen, Jan E E; Delbecq, Ann-Laure M H; Cruysberg, J R M Hans; van Meurs, Jan C; Gan, Ivan M; Berendschot, Tos T J M

    2014-01-01

    In the nineteen-nineties, there was much hype in the European media about presumed laser pointer maculopathy. However, the recent introduction of more powerful and therefore more dangerous laser pointers and their easy availability on the internet necessitates vigilance on the issue. This is an urgent matter, as here we report three cases of proven maculopathy due to an unsafe laser pointer. Three boys aged 13, 9 and 12 years used an unsafe laser pointer as a toy and looked repeatedly into the pointer, resulting in a permanent reduction in visual acuity due to macular damage. Laser pointers are not designed to be children's toys or instruments to annoy people in a crowd. Health authorities and the ophthalmic community should be aware of the potential danger of improper use of high-output laser pointers and warn the general public before the widespread availability of unsafe laser pointers and consequently laser pointer-induced macular damage becomes a true social problem. PMID:25308223

  6. Ultrananocrystalline diamond-CMOS device integration route for high acuity retinal prostheses.

    PubMed

    Ahnood, A; Escudie, M C; Cicione, R; Abeyrathne, C D; Ganesan, K; Fox, K E; Garrett, D J; Stacey, A; Apollo, N V; Lichter, S G; Thomas, C D L; Tran, N; Meffin, H; Prawer, S

    2015-01-01

    High density electrodes are a new frontier for biomedical implants. Increasing the density and the number of electrodes used for the stimulation of retinal ganglion cells is one possible strategy for enhancing the quality of vision experienced by patients using retinal prostheses. The present work presents an integration strategy for a diamond based, high density, stimulating electrode array with a purpose built application specific integrated circuit (ASIC). The strategy is centered on flip-chip bonding of indium bumps to create high count and density vertical interconnects between the stimulator ASIC and an array of diamond neural stimulating electrodes. The use of polydimethylsiloxane (PDMS) housing prevents cross-contamination of the biocompatible diamond electrode with non-biocompatible materials, such as indium, used in the microfabrication process. Micro-imprint lithography allowed edge-to-edge micro-scale pattering of the indium bumps on non-coplanar substrates that have a form factor that can conform to body organs and thus are ideally suited for biomedical applications. Furthermore, micro-imprint lithography ensures the compatibility of lithography with the silicon ASIC and aluminum contact pads. Although this work focuses on 256 stimulating diamond electrode arrays with a pitch of 150 μm, the use of indium bump bonding technology and vertical interconnects facilitates implants with tens of thousands electrodes with a pitch as low as 10 μm, thus ensuring validity of the strategy for future high acuity retinal prostheses, and bionic implants in general. PMID:25877379

  7. Development of microcomputer-based mental acuity tests for repeated-measures studies

    NASA Technical Reports Server (NTRS)

    Kennedy, R. S.; Wilkes, R. L.; Baltzley, D. R.; Fowlkes, J. E.

    1990-01-01

    The purpose of this report is to detail the development of the Automated Performance Test System (APTS), a computer battery of mental acuity tests that can be used to assess human performance in the presence of toxic elements and environmental stressors. There were four objectives in the development of APTS. First, the technical requirements for developing APTS followed the tenets of the classical theory of mental tests which requires that tests meet set criteria like stability and reliability (the lack of which constitutes insensitivity). To be employed in the study of the exotic conditions of protracted space flight, a battery with multiple parallel forms is required. The second criteria was for the battery to have factorial multidimensionality and the third was for the battery to be sensitive to factors known to compromise performance. A fourth objective was for the tests to converge on the abilities entailed in mission specialist tasks. A series of studies is reported in which candidate APTS tests were subjected to an examination of their psychometric properties for repeated-measures testing. From this work, tests were selected that possessed the requisite metric properties of stability, reliability, and factor richness. In addition, studies are reported which demonstrate the predictive validity of the tests to holistic measures of intelligence.

  8. Changes in Near Visual Acuity of Over Time in the Astronaut Corps

    NASA Technical Reports Server (NTRS)

    Taiym, Wafa; Wear, Mary L.; Locke, James; Mason, Sara; VanBaalen, Mary

    2014-01-01

    We hypothesized that visual impairment due to intracranial pressure (VIIP) would increase the rate of which presbyopia would occur in the astronaut population, with long durations flyers at an especially high risk. Presbyopia is characterized as the gradual loss of near visual acuity overtime due to a loss in ability to accommodate. It generally develops in the mid-40s and progresses until about age 65. This analysis considered annual vision exams conducted on active NASA astronauts with spaceflight experience currently between the ages of 40 to 60 years of age. Onset of presbyopia was characterized as a shift of at least 20 units on the standard Snellen test from one annual exam to the next. There were 236 short duration and 48 long duration flyers, the majority of whom did experience onset of presbyopia between age 40 and 60. This shift however, did not necessarily come after spaceflight. In comparing the short and long duration flyers the mean age of onset was 47 years old (SD+/-3.7). The mean of onset within the general population is 45 to 47 years old [1, 2]. The mean age of the onset of presbyopia as compared to the general population indicates that space flight does not induce early development of presbyopia.

  9. Influence of Local Cooling on Proprioceptive Acuity in the Quadriceps Muscle

    PubMed Central

    Estephan, Lorein; Legendre, Martine; Sulpher, Stéphanie

    2001-01-01

    Objective: To test the influence of cooling on proprioceptive acuity as reflected in the ability to discriminate weights. Design and Setting: Participants were trained to perform a weight-discrimination task. Their ability to correctly report small increments in weight was compared before and after local cooling (a 20-minute application of a crushed-ice pack) of the quadriceps muscle group. Data were collected at a university research laboratory. Subjects: Twenty young, physically active adults (undergraduate students; 14 men, 6 women; mean age, 22.1 ± 2.6 years). Measurements: We calculated overall performance in the weight-discrimination task (percentage of discrimination correct) for each participant to estimate the differential threshold (ie, minimal increment in weight that yields a probability of 75% correct responses). Results: Before local cooling, participants discriminated increments in the order of 4% to 10% from the standard weight (mean threshold, 0.17 ± 0.06 kg). After local cooling, the discriminative performance remained, on average, very similar to that seen before cooling (mean threshold, 0.17 ± 0.08 kg; paired t test: t = 0.24, P = .81). Only a small group of participants (n = 5) showed evidence of a decreased ability to discriminate weight after cooling. Conclusions: The perception of force signals required for weight discrimination does not appear to be affected by local cooling of the quadriceps muscle group. This finding provides additional evidence for the relative safety of cold applications and their effect on proprioceptive perceptual abilities. PMID:12937450

  10. Electrical Stimulation of Visual Cortex Can Immediately Improve Spatial Vision.

    PubMed

    Reinhart, Robert M G; Xiao, Wenxi; McClenahan, Laura J; Woodman, Geoffrey F

    2016-07-25

    We can improve human vision by correcting the optics of our lenses [1-3]. However, after the eye transduces the light, visual cortex has its own limitations that are challenging to correct [4]. Overcoming these limitations has typically involved innovative training regimes that improve vision across many days [5, 6]. In the present study, we wanted to determine whether it is possible to immediately improve the precision of spatial vision with noninvasive direct-current stimulation. Previous work suggested that visual processing could be modulated with such stimulation [7-9]. However, the short duration and variability of such effects made it seem unlikely that spatial vision could be improved for more than several minutes [7, 10]. Here we show that visual acuity in the parafoveal belt can be immediately improved by delivering noninvasive direct current to visual cortex. Twenty minutes of anodal stimulation improved subjects' vernier acuity by approximately 15% and increased the amplitude of the earliest visually evoked potentials in lockstep with the behavioral effects. When we reversed the orientation of the electric field, we impaired resolution and reduced the amplitude of visually evoked potentials. Next, we found that anodal stimulation improved acuity enough to be measurable with the relatively coarse Snellen test and that subjects with the poorest acuity benefited the most from stimulation. Finally, we found that stimulation-induced acuity improvements were accompanied by changes in contrast sensitivity at high spatial frequencies. PMID:27374337

  11. Dispersion-correcting potentials can significantly improve the bond dissociation enthalpies and noncovalent binding energies predicted by density-functional theory

    SciTech Connect

    DiLabio, Gino A.; Koleini, Mohammad

    2014-05-14

    Dispersion-correcting potentials (DCPs) are atom-centered Gaussian functions that are applied in a manner that is similar to effective core potentials. Previous work on DCPs has focussed on their use as a simple means of improving the ability of conventional density-functional theory methods to predict the binding energies of noncovalently bonded molecular dimers. We show in this work that DCPs developed for use with the LC-ωPBE functional along with 6-31+G(2d,2p) basis sets are capable of simultaneously improving predicted noncovalent binding energies of van der Waals dimer complexes and covalent bond dissociation enthalpies in molecules. Specifically, the DCPs developed herein for the C, H, N, and O atoms provide binding energies for a set of 66 noncovalently bonded molecular dimers (the “S66” set) with a mean absolute error (MAE) of 0.21 kcal/mol, which represents an improvement of more than a factor of 10 over unadorned LC-ωPBE/6-31+G(2d,2p) and almost a factor of two improvement over LC-ωPBE/6-31+G(2d,2p) used in conjunction with the “D3” pairwise dispersion energy corrections. In addition, the DCPs reduce the MAE of calculated X-H and X-Y (X,Y = C, H, N, O) bond dissociation enthalpies for a set of 40 species from 3.2 kcal/mol obtained with unadorned LC-ωPBE/6-31+G(2d,2p) to 1.6 kcal/mol. Our findings demonstrate that broad improvements to the performance of DFT methods may be achievable through the use of DCPs.

  12. Expanding the Parameters for Excellence in Patient Assignments: Is Leveraging an Evidence-Data-Based Acuity Methodology Realistic?

    PubMed

    Gray, Joel; Kerfoot, Karlene

    2016-01-01

    Finding the balance of equitable assignments continues to be a challenge for health care organizations seeking to leverage evidence-based leadership practices. Ratios and subjective acuity strategies for nurse-patient staffing continue to be the dominant approach in health care organizations. In addition to ratio-based assignments and acuity-based assignment models driven by financial targets, more emphasis on using evidence-based leadership strategies to manage and create science for effective staffing is needed. In particular, nurse leaders are challenged to increase the sophistication of management of patient turnover (admissions, discharges, and transfers) and integrate tools from Lean methodologies and quality management strategies to determine the effectiveness of nurse-patient staffing. PMID:26636229

  13. Color matches in diseased eyes with good acuity: detection of deficits in cone optical density and in chromatic discrimination

    NASA Astrophysics Data System (ADS)

    Swanson, William H.; Fish, Gary E.

    1995-10-01

    Reduced foveal cone optical density in diseased eyes with normal acuity can affect color matches. Using field diameters of 1 deg, 2 deg, 4 deg, and 8 deg, we measured mean color-match midpoints and match widths in patients who had good acuity and who hereditary macular degeneration ( n=12 ), retinitis pigmentosa ( n=19 ), and glaucoma ( n=18 ). Results were compared with those for normal observers of comparable ages. Mean color-match midpoints were abnormal only for the population with hereditary macular degeneration, indicating a reduction in cone optical density in the central 4 deg. Mean color-match widths were enlarged for both hereditary macular degeneration and retinitis pigmentosa, a result consistent with a reduction in the number of foveal cones. chromatic discrimination, macular degeneration, retinitis pigmentosa, glaucoma.

  14. Is 20/20 vision good enough? Visual acuity differences within the normal range predict contour element detection and integration

    PubMed Central

    Keane, Brian P.; Kastner, Sabine; Paterno, Danielle; Silverstein, Steven M.

    2014-01-01

    Contour integration (CI) combines appropriately aligned and oriented elements into continuous boundaries. Collinear facilitation (CF) occurs when a low-contrast oriented element becomes more visible when flanked by collinear high-contrast elements. Both processes rely at least partly on long-range horizontal connections in early visual cortex, and thus both have been extensively studied to understand visual cortical functioning in aging, development, and clinical disorders. Here, we ask: Can acuity differences within the normal range predict CI or CF? To consider this question, we measured binocular visual acuity and compared subjects with 20/20 vision to those with better-than-20/20 vision (SharpPerceivers) on two tasks. In the CI task, subjects located an integrated shape embedded in varying amounts of noise; in the CF task, subjects detected a low-contrast element flanked by collinear or orthogonal high-contrast elements. In each case, displays were scaled in size to modulate element visibility and spatial frequency (4-12 cycles/deg). SharpPerceivers could integrate contours under noisier conditions than the 20/20 group (p=.0002) especially for high spatial frequency displays. Moreover, although the two groups exhibited similar collinear facilitation, SharpPerceivers could detect the central target with lower contrast at high spatial frequencies (p<.05). These results suggest that small acuity differences within the normal range—corresponding to about a one line difference on a vision chart—strongly predict element detection and integration. Furthermore, simply ensuring that subjects have normal or corrected-to-normal vision is not sufficient when comparing groups on contour tasks; visual acuity confounds also need to be ruled out. PMID:24845876

  15. Emmetropization, visual acuity, and strabismus outcomes among hyperopic infants followed with partial hyperopic corrections given in accordance with dynamic retinoscopy

    PubMed Central

    Somer, D; Karabulut, E; Cinar, F G; Altiparmak, U E; Unlu, N

    2014-01-01

    Object To record emmetropization, visual acuity, and strabismus outcomes among hyperopic infants followed with partial hyperopic corrections given in accordance with dynamic retinoscopy (DR). Methods Infants (3.5–12 months of age) with ≥5 D hyperopia were followed without glasses or partial hyperopic corrections prescribed according to their near dynamic accommodative abilities determined by DR responses at the initial visit and follow-ups. Refraction and binocular accommodative ability assessments were made at 3-month intervals up to the age of 1 and at 6-month intervals afterwards for a mean 35.4±2.1 months; main outcome measures being the development of esotropia, emmetropization rate, and visual acuity level after emmetropization period. Results Among 211, 146 were normal accommodators initially (Group 1). These infants were followed without treatment and none presented with strabismus. Sixty-five infants were hypo-accommodators (Group 2) and received minimum DR-based corrections. Of the 65 infants 31 (48%) developed strabismus (Group 2B). The remaining 34 constituted Group 2A. Each of the three groups showed an overall reduction of hyperopia by 0.37±0.25 days per year, 0.50±0.28 days per year, and 0.60±0.20 days per year, respectively. Visual acuity assessments among Groups 1 and 2A revealed normal values (0.2–0.0 LogMAR); among Group 2B 19% were within normal range. Conclusions Binocular accommodative behavior at the initial visit seems to be one of the indicators for pointing out infants at risk of developing strabismus and amblyopia. Prescription of DR-based corrections to hyperopic orthotropic infants does not impede emmetropization and result in normal visual acuities after emmetropization period. PMID:25033902

  16. Varying protein source and quantity does not significantly improve weight loss, fat loss, or satiety in reduced energy diets among midlife adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This pilot study tested whether varying protein source and quantity in a reduced energy diet would result in significant differences in weight, body composition, and renin angiotensin aldosterone system activity in midlife adults. Eighteen subjects enrolled in a 5 month weight reduction study, invol...

  17. Significant improvement following combination treatment with mefloquine and mirtazapine in a patient with progressive multifocal leukoencephalopathy after allogeneic peripheral blood stem cell transplantation.

    PubMed

    Yoshida, Hitoshi; Ohshima, Kenji; Toda, Jun; Kusakabe, Shinsuke; Masaie, Hiroaki; Yagi, Toshinari; Ishikawa, Jun

    2014-01-01

    We report a case of a 40-year-old female who developed progressive multifocal leukoencephalopathy (PML), which is associated with JC virus reactivation, after allogeneic hematopoietic cell transplantation. As she had been suffering from graft-versus-host disease and lung damage after pneumocystis pneumonia, the administration of calcineurin inhibitor and steroid could not be discontinued. However, she showed a favorable improvement in clinical symptoms and imaging findings after treatment with the anti-malarial drug, mefloquine and a serotonin receptor blocker, mirtazapine. Continuation of the treatment for eight months finally led to the clearance of the JC virus from her cerebrospinal fluid. She currently shows no neurological disturbance and has resumed her daily activities. PML due to the severe immunosuppressive condition has been reported as a fatal complication after allo-SCT. Our case suggests that combination treatment with mefloquine and mirtazapine may be of great value for the treatment for PML patients in the post allo-SCT setting, although it is difficult to say whether the combination treatment alone led to improvement. Further clinical study is needed to clarify the efficacy of these drugs for the treatment of PML. PMID:24264833

  18. Soft-Etching Copper and Silver Electrodes for Significant Device Performance Improvement toward Facile, Cost-Effective, Bottom-Contacted, Organic Field-Effect Transistors.

    PubMed

    Wang, Zongrui; Dong, Huanli; Zou, Ye; Zhao, Qiang; Tan, Jiahui; Liu, Jie; Lu, Xiuqiang; Xiao, Jinchong; Zhang, Qichun; Hu, Wenping

    2016-03-01

    Poor charge injection and transport at the electrode/semiconductor contacts has been so far a severe performance hurdle for bottom-contact bottom-gate (BCBG) organic field-effect transistors (OFETs). Here, we have developed a simple, economic, and effective method to improve the carrier injection efficiency and obtained high-performance devices with low cost and widely used source/drain (S/D) electrodes (Ag/Cu). Through the simple electrode etching process, the work function of the electrodes is more aligned with the semiconductors, which reduces the energy barrier and facilitates the charge injection. Besides, the formation of the thinned electrode edge with desirable micro/nanostructures not only leads to the enlarged contact side area beneficial for the carrier injection but also is in favor of the molecular self-organization for continuous crystal growth at the contact/active channel interface, which is better for the charge injection and transport. These effects give rise to the great reduction of contact resistance and the amazing improvement of the low-cost bottom-contact configuration OFETs performance. PMID:26967358

  19. Cone survival and preservation of visual acuity in an animal model of retinal degeneration.

    PubMed

    Piano, Ilaria; Novelli, Elena; Gasco, Paolo; Ghidoni, Riccardo; Strettoi, Enrica; Gargini, Claudia

    2013-06-01

    The prevention of cone loss during retinal degeneration is a major goal of most therapeutic strategies in retinal degenerative diseases. An intriguing issue in the current research in this field is to understand why a genetic mutation that affects rods eventually leads to cone death. The main objective of the present study was to investigate to what extent rescuing rods from degeneration affects the survival of cones and prevents functional impairment of the visual performance. To this purpose, we compared rod and cone viabilities by both ex vivo and in vivo determinations in the rd10 mutant mouse, a validated model of human retinitis pigmentosa. The ex vivo experiments included morphological and biochemical tests, whereas in vivo studies compared the rod-mediated scotopic with the cone-mediated photopic electroretinogram. We also determined the overall visual performance by behaviorally testing the visual acuity (VA). The electroretinogram measurements showed that the kinetics of the photopic response in rd10 mice was slowed down with respect to the age-paired wild-type at a very early stage of the disease, when rods were still present and responsive. We then tested cone viability and function under a pharmacological scheme previously shown to prolong rod survival. The treatment consisted of eye drop administration of myriocin, an inhibitor of the biosynthesis of ceramide, a powerful proapoptotic messenger. The results of biochemical, morphological and functional assays converged to show that, in treated rd10 mice cone photoreceptors, the inner retina and overall visual performance were preserved well after rod death. PMID:23551187

  20. Acuity-based nurse assignment and patient scheduling in oncology clinics.

    PubMed

    Liang, Bohui; Turkcan, Ayten

    2016-09-01

    The oncology clinics use different nursing care delivery models to provide chemotherapy treatment to cancer patients. Functional and primary care delivery models are the most commonly used methods in the clinics. In functional care delivery model, patients are scheduled for a chemotherapy appointment without considering availabilities of individual nurses, and nurses are assigned to patients according to patient acuities, nursing skill, and patient mix on a given day after the appointment schedule is determined. Patients might be treated by different nurses on different days of their treatment. In primary care delivery model, each patient is assigned to a primary nurse, and the patients are scheduled to be seen by the same nurse every time they come to the clinic for treatment. However, these clinics might experience high variability in daily nurse workload due to treatment protocols that should be followed strictly. In that case, part-time nurses can be utilized to share the excess workload of the primary nurses. The aim of this study is to develop optimization methods to reduce the time spent for nurse assignment and patient scheduling in oncology clinics that use different nursing care delivery models. For the functional delivery model, a multiobjective optimization model with the objectives of minimizing patient waiting times and nurse overtime is proposed to solve the nurse assignment problem. For the primary care delivery model, another multiobjective optimization model with the objectives of minimizing total overtime and total excess workload is proposed to solve the patient scheduling problem. Spreadsheet-based optimization tools are developed for easy implementation. Computational results show that the proposed models provide multiple nondominated solutions, which can be used to determine the optimal staffing levels. PMID:25595434

  1. Using edge-preserving algorithm with non-local mean for significantly improved image-domain material decomposition in dual-energy CT

    NASA Astrophysics Data System (ADS)

    Zhao, Wei; Niu, Tianye; Xing, Lei; Xie, Yaoqin; Xiong, Guanglei; Elmore, Kimberly; Zhu, Jun; Wang, Luyao; Min, James K.

    2016-02-01

    Increased noise is a general concern for dual-energy material decomposition. Here, we develop an image-domain material decomposition algorithm for dual-energy CT (DECT) by incorporating an edge-preserving filter into the Local HighlY constrained backPRojection reconstruction (HYPR-LR) framework. With effective use of the non-local mean, the proposed algorithm, which is referred to as HYPR-NLM, reduces the noise in dual-energy decomposition while preserving the accuracy of quantitative measurement and spatial resolution of the material-specific dual-energy images. We demonstrate the noise reduction and resolution preservation of the algorithm with an iodine concentrate numerical phantom by comparing the HYPR-NLM algorithm to the direct matrix inversion, HYPR-LR and iterative image-domain material decomposition (Iter-DECT). We also show the superior performance of the HYPR-NLM over the existing methods by using two sets of cardiac perfusing imaging data. The DECT material decomposition comparison study shows that all four algorithms yield acceptable quantitative measurements of iodine concentrate. Direct matrix inversion yields the highest noise level, followed by HYPR-LR and Iter-DECT. HYPR-NLM in an iterative formulation significantly reduces image noise and the image noise is comparable to or even lower than that generated using Iter-DECT. For the HYPR-NLM method, there are marginal edge effects in the difference image, suggesting the high-frequency details are well preserved. In addition, when the search window size increases from 11× 11 to 19× 19 , there are no significant changes or marginal edge effects in the HYPR-NLM difference images. The reference drawn from the comparison study includes: (1) HYPR-NLM significantly reduces the DECT material decomposition noise while preserving quantitative measurements and high-frequency edge information, and (2) HYPR-NLM is robust with respect to parameter selection.

  2. Facilitating endoscopic submucosal dissection: the suture-pulley method significantly improves procedure time and minimizes technical difficulty compared with conventional technique: an ex vivo study (with video)

    PubMed Central

    Aihara, Hiroyuki; Kumar, Nitin; Ryou, Marvin; Abidi, Wasif; Ryan, Michele B.; Thompson, Christopher C.

    2015-01-01

    Background The lack of countertraction in endoscopic submucosal dissection (ESD) results in increased technical demand and procedure time. Although the suture-pulley method for countertraction has been reported, its effectiveness compared with the traditional ESD technique remains unclear. Objective To objectively analyze efficacy of countertraction using the suture-pulley method for ESD. Design Prospective ex vivo animal study. Setting Animal laboratory. Interventions Twenty simulated gastric lesions were created in porcine stomachs by using a standard circular template 30 mm in diameter. In the control arm (n = 10), ESD was performed by using the standard technique. In the suture-pulley arm (N = 10), a circumferential incision was made, and an endoscopic suturing device was used to place the suture pulley. Main Outcome Measurements The primary outcome of this study was total procedure time. Results The median total procedure time with the suture-pulley method was significantly shorter than the traditional ESD technique (median, 25% to 75%, interquartile range [IQR]: 531 seconds [474.3–549.3 seconds] vs 845 seconds [656.3–1547.5 seconds], P < .001). The median time (IQR) for suture-pulley placement was 160.5 seconds (150.0–168.8 seconds). Although there was a significantly longer procedure time for proximal versus middle/lower stomach lesions with traditional ESD (median, 1601 seconds; IQR, 1547.5–1708.8 seconds vs median, 663 seconds; IQR, 627.5–681.8 seconds; P =.01), there was no significant difference in procedure time for lesions of various locations when using the suture-pulley method. Compared with traditional ESD, the suture-pulley method was less demanding in all categories evaluated by the NASA Task Load Index. Limitations Ex vivo study. Conclusions The suture-pulley method facilitates direct visualization of the submucosal layer during ESD and significantly reduces procedure time and technical difficulty. In addition, the benefit of the suture

  3. Combined Use of Hyperbaric and Hypobaric Ropivacaine Significantly Improves Hemodynamic Characteristics in Spinal Anesthesia for Caesarean Section: A Prospective, Double-Blind, Randomized, Controlled Study

    PubMed Central

    Quan, ZheFeng; Tian, Ming; Chi, Ping; Li, Xin; He, HaiLi; Luo, Chao

    2015-01-01

    Purpose To observe the hemodynamic changes of parturients in the combined use of hyperbaric (4 mg) and hypobaric (6 mg) ropivacaine during spinal anesthesia for caesarean section in this randomized double-blind study. Methods Parturients (n = 136) undergoing elective cesarean delivery were randomly and equally allocated to receive either combined hyperbaric and hypobaric ropivacaine (Group A) or hyperbaric ropivacaine (Group B). Outcome measures were: hemodynamic characteristics, maximum height of sensory block, time to achieve T8 sensory blockade level, incidence of complications, Apgar scores at 1 and 5 min, and neonatal blood gas analysis. Results Group A had a lower level of sensory blockade (T6 [T6-T7]) and longer time to achieve T8 sensory blockade level (8 ± 1.3 min) than did patients in Group B (T3 [T2-T4] and 5 ± 1.0 min, respectively; P < 0.001, both). The incidence rates for hypotension, nausea, and vomiting were significantly lower in Group A (13%, 10%, and 3%, respectively) than Group B (66%, 31%, and 13%; P < 0.001, P = 0.003, P = 0.028). Conclusions Combined use of hyperbaric (4 mg) and hypobaric (6 mg) ropivacaine significantly decreased the incidences of hypotension and complications in spinal anesthesia for caesarean section by extending induction time and decreasing the level of sensory blockade. Trial Registration Chinese Clinical Trial Register ChiCTR-TRC-13004622 PMID:25970485

  4. Site-specific replacement of the thymine methyl group by fluorine in thrombin binding aptamer significantly improves structural stability and anticoagulant activity

    PubMed Central

    Virgilio, Antonella; Petraccone, Luigi; Vellecco, Valentina; Bucci, Mariarosaria; Varra, Michela; Irace, Carlo; Santamaria, Rita; Pepe, Antonietta; Mayol, Luciano; Esposito, Veronica; Galeone, Aldo

    2015-01-01

    Here we report investigations, based on circular dichroism, nuclear magnetic resonance spectroscopy, molecular modelling, differential scanning calorimetry and prothrombin time assay, on analogues of the thrombin binding aptamer (TBA) in which individual thymidines were replaced by 5-fluoro-2′-deoxyuridine residues. The whole of the data clearly indicate that all derivatives are able to fold in a G-quadruplex structure very similar to the ‘chair-like’ conformation typical of the TBA. However, only ODNs TBA-F4 and TBA-F13 have shown a remarkable improvement both in the melting temperature (ΔTm ≈ +10) and in the anticoagulant activity in comparison with the original TBA. These findings are unusual, particularly considering previously reported studies in which modifications of T4 and T13 residues in TBA sequence have clearly proven to be always detrimental for the structural stability and biological activity of the aptamer. Our results strongly suggest the possibility to enhance TBA properties through tiny straightforward modifications. PMID:26582916

  5. Disruption of the 5S RNP-Mdm2 interaction significantly improves the erythroid defect in a mouse model for Diamond-Blackfan anemia.

    PubMed

    Jaako, P; Debnath, S; Olsson, K; Zhang, Y; Flygare, J; Lindström, M S; Bryder, D; Karlsson, S

    2015-11-01

    Diamond-Blackfan anemia (DBA) is a congenital erythroid hypoplasia caused by haploinsufficiency of genes encoding ribosomal proteins (RPs). Perturbed ribosome biogenesis in DBA has been shown to induce a p53-mediated ribosomal stress response. However, the mechanisms of p53 activation and its relevance for the erythroid defect remain elusive. Previous studies have indicated that activation of p53 is caused by the inhibition of mouse double minute 2 (Mdm2), the main negative regulator of p53, by the 5S ribonucleoprotein particle (RNP). Meanwhile, it is not clear whether this mechanism solely mediates the p53-dependent component found in DBA. To approach this question, we crossed our mouse model for RPS19-deficient DBA with Mdm2(C305F) knock-in mice that have a disrupted 5S RNP-Mdm2 interaction. Upon induction of the Rps19 deficiency, Mdm2(C305F) reversed the p53 response and improved expansion of hematopoietic progenitors in vitro, and ameliorated the anemia in vivo. Unexpectedly, disruption of the 5S RNP-Mdm2 interaction also led to selective defect in erythropoiesis. Our findings highlight the sensitivity of erythroid progenitor cells to aberrations in p53 homeostasis mediated by the 5S RNP-Mdm2 interaction. Finally, we provide evidence indicating that physiological activation of the 5S RNP-Mdm2-p53 pathway may contribute to function