Blue Lenses Research Articles

“Objection to Roast Chicken”1: Feminist-Vegan Incidents in Daphne du Maurier’s “The Chamois” and “The Blue Lenses”

“Objection to Roast Chicken”1: Feminist-Vegan Incidents in Daphne du Maurier’s “The Chamois” and “The Blue Lenses”

Blaulichtfilter und deren Auswirkung auf den Pupillenlichtreflex

Purpose. The increasing exposure to artificial blue light sources has spawned an equal interest in spectacle lenses that protect against this potentially harmful proportion of light. This study compared the performance of different blue light filtering spectacle lenses and investigated whether a reduction in blue light transmission affects light-dependent physiological processes. Material and Methods. The wavelength-specific transmission of various spectacle lenses was determined by spectrometer and the influence of the lenses on the PIPR (Post Illumination Pupil Response) was evaluated. Thirty-six eyes of 18 adults (20 - 30 years) were measured by monocular, direct chromatic pupillometry with and without blue light filtering lenses. The modified pupillometer (PupilX from Albomed GmbH) with red and blue stimulation was used with a pupil exposure time of 30 seconds (darkness: 1 s; light stimulus: 1 s; darkness: 28 s). Results. In the main action spectrum of the blue light hazard (400 nm ≤ λ ≤ 500 nm), the transparent blue light filter showed lower absorption compared to “comfort- and wellness” lenses of filter category 1 (absorption: 19.60 % to 25.27 % and 65.04 % to 97.43 %). In the early and late phase of the post illumination pupil reflex (PIPR) after a blue light stimulus, we detected a significantly smaller area under the curve (p < 0.001), a larger normalized pupil diameter (p < 0.001), and a larger curvature index in an exponential interpolation (p < 0.001) when the “comfort- and wellness-” lenses were used. Conclusion. Blue light filtering lenses have been shown to reduce the transmission of blue light and thus can minimize the risk of blue light exposure. By simultaneously reducing the stimulation of intrinsic photosensitive retinal ganglion cells (ipRGCs), light-modulated physiological processes such as circadian regulation could be altered. The use of “comfortand wellness” lenses showed a significant change in the PIPR. An influence by transparent, blue-light filtering spectacle lenses could not be detected. Keywords Blue light filtering spectacle lenses, blue light hazard, chromatic pupillometry, intrinsically photosensitive retinal ganglion cells, circadian rhythm

Spectrophotometric properties of commercially available blue blockers across multiple lighting conditions

ABSTRACT Lenses that filter short-wavelength (“blue”) light are commercially marketed to improve sleep and circadian health. Despite their widespread use, minimal data are available regarding their comparative efficacy in curtailing blue light exposure while maintaining visibility. Fifty commercial lenses were evaluated using five light sources: a blue LED array, a computer tablet display, an incandescent lamp, a fluorescent overhead luminaire, and sunlight. Absolute irradiance was measured at baseline and for each lens across the visual spectrum (380–780 nm), which allowed calculation of percent transmission. Transmission specificity was also calculated to determine whether light transmission was predominantly circadian-proficient (455–560 nm) or non-proficient (380–454 nm and 561–780 nm). Lenses were grouped by tint and metrics were compared between groups. Red-tinted lenses exhibited the lowest transmission of circadian-proficient light, while reflective blue lenses had the highest transmission. Orange-tinted lenses transmitted similar circadian-proficient light as red-tinted lenses but transmitted more non-circadian-proficient light, resulting in higher transmission specificity. Orange-tinted lenses had the highest transmission specificity while limiting biologically active light exposure in ordinary lighting conditions. Glasses incorporating these lenses currently have the greatest potential to support circadian sleep-wake rhythms.

Influence of Wearing Blue Lenses on Melatonin Production and Performance in Volleyball Players.

We analyzed the effects of wearing blue lenses on melatonin level, physical and cognitive performance. Fifteen youth volleyball players (15.0±1.5 yrs) attended the laboratory on 3 occasions (48-h interval): on the 1 st visit they were familiarized with the procedures of the study, and on 2 nd and 3 rd visits they were submitted to the testing protocol wearing transparent (control) or blue lens glasses in a counterbalanced crossover design. The protocol consisted of 10 min in “total darkness,” 30 min of light stimulation (wearing blue or transparent lenses), followed by an attentional test, and an agility T-test (without wearing the glasses). Samples of saliva (to determine melatonin concentration) were obtained pre- and post-exposure (30 min) to artificial light, wearing the lenses. Sleepiness, alertness, attention, mood, and perceived recovery status and performance variables (reaction time and T-test) were assessed after lens exposure. Melatonin levels did not differ within and between groups (blue lenses, pre: 0.79±0.73 and post: 1.19±1.374 pg/dl, p=0.252, effect size (ES)=0.38; control, pre: 0.97±1.00 and post: 0.67±0.71 pg/dl, p=0.305, ES=–0.35). Nonetheless, melatonin differences were significantly correlated with physical sedation for glasses with blue lenses (r=−0.526; p=0.04). No other variables differed (p>0.05) between protocols, including T-test performance (p=0.07; ES=0.41). Blue lenses do not influence melatonin levels, cognitive/physical performance, and mood status in amateur youth volleyball players.

Efficacy of color lenses in abolishing photosensitivity: Beyond the one-type-fits-all approach?

ObjectiveRed-light filtering lenses represent an additional option to medication in photosensitive epilepsy. Blue lenses (Clarlet Z1 F133) can dramatically reduce seizure frequency, with a substantial restriction in luminance that can limit their applicability in daily life. We investigated the efficacy of 4 blue lenses with higher transmittance and reduced chromatic distortion in abolishing the photoparoxysmal EEG response (PPR) compared to the gold-standard Z1 lenses. MethodsWe reviewed EEG data during photic-and pattern stimulation in 19 consecutive patients (6–39 years) with photosensitivity (PS). Stimulation was performed at baseline and while wearing Z1 and the four new lenses. Lenses were tested in the same session by asking the patient to wear them in a sequentially randomized fashion while stimulating again with the most provocative photic/pattern stimuli. The primary outcome was the change in the initial PPR observed for each lens, categorized as no change, reduction, and abolition. ResultsPhotosensitivity was detected in 17 subjects (89.5%); pattern sensitivity (PtS) was identified in 14 patients (73.7%). The highest percentages of PPR abolition/reduction were observed with Z1, for both PS and PtS. Regarding the new lenses, B1 + G1 offered the best rates, followed by B1 + G2. B1 + G3 and B1 showed lower efficacy rates, particularly for PtS. In the comparative analysis, no significant differences in PPR suppression were detected between the five lenses for PS. For PtS, the capacity of Z1 for PPR abolition was significantly higher compared with B1 + G3 and B1. ConclusionsThis preliminary study suggests efficacy of the new group of blue lenses with potentially greater tolerability, particularly in regions with fewer sunlight hours during winter. In line with the current trend for personalized approach to treatment, this study suggests that in some patients there might be scope in extending the testing to offer the lens with the higher transmittance effective in abolishing the PPR.

The quantitative effect of blue lenses on pediatric photoparoxysmal response – An electroencephalographic cohort study

PurposeTo determine and quantify the effect of blue lenses (Z1) on photosensitivity (PS) suppression in patients aged 5-18 years with and without epilepsy. MethodsThe retrospective cohort study was carried out in 100 pediatric patients aged 5-18 years with grade 4 PS assessed with EEG for medical indications. All EEG procedures were carried out and recordings assessed by two independent researchers. The study cohort was divided into groups with and without the diagnosis of epilepsy. The overall effect of the Z1 lenses on photoparoxysmal response (PPR) was determined by directly comparing the maximum discharge values in each patient without and with Z1 lenses in a within-subject design yielding the index of overall improvement (IOI). The differences in PS suppression by brain region and side were assessed by an additional between-subject comparison of age groups (below and above 14 years). Then, overall findings were compared with the PPR change criteria developed in 2006 by Capovilla (PPR disappearance, persistence, or attenuation) which warranted another subset analysis. Finally, in a between-subject design, we assessed whether the presence of epilepsy affects the intensity of PPR in children with PS, compared to non-epilepsy children. ResultsThe IOI in the entire cohort was 66.1±2.5% (P<0.001). There were no significant differences in IOI between the left and right hemispheres, between the age groups, and between the epilepsy and non-epilepsy groups, despite some qualitative variation. With reference to literature findings, whereas median IOI were comparable in PPR disappearance and attenuation subsets, they differed significantly from the median IOI in the PPR persistence subset. ConclusionUsing Z1 lenses results in neither a complete PPR disappearance, nor a complete lack of effect. However, the correlation between the quantified PS suppression and the Z1 filter may be expected to become a valuable piece of information for both clinicians and manufacturers.

256 Spectrophotometric Properties of 31 Different Commercially Available Blue Blocking Glasses Under Electric Room Lighting

Abstract Introduction Blue blocking glasses are often marketed to promote relaxation, sleep, and circadian health by attenuating melatonin-suppressing light exposure. But these glasses represent a wide range of tint and other lens properties. Further, the utility of these glasses under ecologically valid indoor conditions (where light is typically generated from overhead broadspectrum fluorescent lamps) is still unclear, especially across various products. Methods A calibrated spectroradiometer (Ocean Insight), cosine corrector, optic fiber, and software package were used to measure the absolute irradiance (uW/cm^2/nm) emitted from overhead fluorescent lighting in a closeted dark room. Thirty-one commercially available blue blockers were individually placed between the cosine corrector and the luminaire, at a standardized distance and angle, where intensity was measured and analyzed. Each lens was evaluated individually relative to the light source under identical conditions. Then, lenses were collapsed by type into the following groups: red-tinted lenses (RTL), orange-tinted lenses (OTL), orange-tinted lenses with blue reflectivity (OBL), brown-tinted lenses (BTL), yellow-tinted lenses (YTL), and clear reflective blue lenses (RBL). Results There was significant variation in light-blocking across lens types (one-way ANOVA, p &amp;lt; 0.0001). On average, RTL and BTL restricted 59% of the visible light measured from 380-780nm. OTL blocked 47% of the light in this range, while OBL blocked 29%. Both YTL and RBL blocked 14% of the exposure. When narrowing the range of light to 440-530nm (the part of the spectrum most likely to produce a response from melanopsin-expressing retinal ganglion cells), we estimated the following performance: the RTL and OTL blocked close to 100% of the light, OBL blocked 98%, BTL blocked 80%, YTL blocked 33%, and RBL blocked 15%. These differences were statistically significant (one-way ANOVA, p &amp;lt; 0.0001). Individual lenses performed variably within groups, but these differences were small. Conclusion Focusing on the portion of the visible spectrum most likely to suppress melatonin secretion, RTL and OTL blocked exposure the best, followed by OBL, BTL, YTL, and (lastly) RBL. Support (if any) R01MD011600, R01DA051321

258 Blue Blockers’ Ability to Block Circadian-Active Light Emitted from a Tablet

Abstract Introduction Short-wavelength light emitted from electronic devices in the evening can harm circadian health by suppressing endogenous melatonin and phase-delaying the timing of the wake-sleep cycle. Blue-blocking glasses are one possible intervention to reduce this exposure. The present study evaluated the differential ability of commercially available blue-blockers to filter out the blue range of visible-spectrum light emitted by a common electronic device. Methods A calibrated spectroradiometer (Ocean Insight), cosine corrector, optic fiber, and software package were used to measure the absolute irradiance (uW/cm^2/nm) emitted from a commercially-available computer tablet (iPad) displaying a blank white screen in a closeted dark room. Thirty-one commercially-available blue-blockers were individually placed between the cosine corrector and the tablet. At a standardized distance and angle, the resulting intensity profile was measured and analyzed. Each lens was evaluated individually relative to the light source and then evaluated across subtypes, including red-tinted lenses (RTL), orange-tinted lenses (OTL), orange-tinted lenses with blue reflectivity (OBL), brown-tinted lenses (BTL), yellow-tinted lenses (YTL), and clear reflective blue lenses (RBL). Results There was significant variation in tablet-generated light-blocking across the full spectrum (one-way ANOVA, p &amp;lt; 0.0001) and for the 440-530nm range in particular (one-way ANOVA, p &amp;lt; 0.0001). RTL blocked 99%, OTL blocked 81%, OBL blocked 75%, BTL blocked 83%, YTL blocked 33%, and RBL blocked 17% of broadspectrum light (380-780nm). In the 440nm-530nm range, RTL, OTL, and OBL blocked 100% of the emission, while BTL blocked 81%, YTL blocked 47%, and RBL blocked 18% of it. Conclusion When using a popular tablet device, RTL, OTL and OBL blocked the most circadian photosensitive parts of the light exposure, indicating they can best preserve the timing of endogenous melatonin secretion in the presence of tablet light at night. By contrast, RBL demonstrated very little efficacy. Support (if any) R01MD011600, R01DA051321

Tightening weak lensing constraints on the ellipticity of galaxy-scale dark matter haloes

Cosmological simulations predict that galaxies are embedded into triaxial dark matter haloes, which appear approximately elliptical in projection. Weak gravitational lensing allows us to constrain these halo shapes and thereby test the nature of dark matter. Weak lensing has already provided robust detections of the signature of halo flattening at the mass scales of groups and clusters, whereas results for galaxies have been somewhat inconclusive. Here we combine data from five weak lensing surveys (NGVSLenS, KiDS/KV450, CFHTLenS, CS82, and RCSLenS, listed in order of most to least constraining) in order to tighten observational constraints on galaxy-scale halo ellipticity for photometrically selected lens samples. We constrain fh, the average ratio between the aligned component of the halo ellipticity and the ellipticity of the light distribution, finding fh = 0.303−0.079+0.080 for red lens galaxies and fh = 0.217−0.159+0.160 for blue lens galaxies when assuming elliptical Navarro-Frenk-White density profiles and a linear scaling between halo ellipticity and galaxy ellipticity. Our constraints for red galaxies constitute the currently most significant (3.8σ) systematics-corrected detection of the signature of halo flattening at the mass scale of galaxies. Our results are in good agreement with expectations from the Millennium Simulation that apply the same analysis scheme and incorporate models for galaxy–halo misalignment. Assuming these misalignment models and the analysis assumptions stated above are correct, our measurements imply an average dark matter halo ellipticity for the studied red galaxy samples of ⟨|ϵh|⟩ = 0.174 ± 0.046, where |ϵh| = (1 − q)/(1 + q) relates to the ratio q = b/a of the minor and major axes of the projected mass distribution. Similar measurements based on larger upcoming weak lensing data sets can help to calibrate models for intrinsic galaxy alignments, which constitute an important source of systematic uncertainty in cosmological weak lensing studies.

PREMENSTRUAL SYNDROME DALAM FOTOGRAFI EKSPRESI

Premenstrual Syndrome is a symptom experienced by women before menstruation arrives. Many stories in the form of complaints from female friends. Based on this, ideas emerged to create photographic works of expression about the effects of Premenstrual Syndrome that were packaged with anaglyph technique. The impact to be visualized is a physical, psychological, and emotional symptom in the period before and until menstruation is over. Premenstrual syndrome information that has been collected through observation will be displayed visually by the medium of photography and using the object of a professional female model, as well as the addition of supporting properties to reinforce the message to be conveyed so as not to develop the meaning that comes out of the ideas that have been made. The work of photography created is a work of expression photography. This creation has an embodiment concept that displays visuals from the development of three-dimensional photographs, namely anaglyph and how to see this work must use anaglyph glasses, in the first glasses using a red colored glass lens and the second glasses using a blue lens glass and then how to view works using these glasses in turn. As for the obstacles that were experienced in the presentation of the embodiment of works including akat, place and time. The place is very influential on the atmosphere that appears in the photo, so the choice of place must be really in accordance with the concept to be appointed.Keywords: Premenstrual Syndrome, anaglyph, fine art photography.

Analysis on the Color Reproduction of Near Infrared Absorbing Lenses and Tinted Lenses

Purpose : To compare the objective and subjective colorimetry so as to evaluate the color accuracy of the near infrared absorbing lenses(IR lenses). Methods : The 15#(Red), 16#(Yellow) and 17#(Green) of the Colorchecker Classiccolor charts were set as virtual traffic signals for measuring objective colorimetry. The objective colorimetry of virtual traffic signals were measured by digital camera attached each test lenses. The original color and measured color by each test lens were represented by CIE 1976 L*a*b* color coordinates, and the color distortion were analyzed by ΔE* ab of the distance between color coordinates of the original and colorimetric color. 32 subjects were participated to the subjective colorimetry. The observed colors of traffic signals were selected from the Korean color standard digital palette, and compared with the original color. Results : In the objective colorimetry, the color distortion of yellow and green virtual traffic signals by near infrared absorbing lenses was found to be the smallest among the test lenses. The color distortion of red virtual traffic signals by near infrared absorbing lenses was greater than the green lens, but less compared to the brown, gray, and blue lenses. In the subjective colorimetry, the color distortion by near infrared absorbing lenses was more than that of brown lenses, similar to blue and green lenses, and less than that of gray lenses. Conclusion : The color distortion of the near infrared absorbing lenses was the smallest in the objective colorimetry compared to other test lenses, but there was no significant difference in the subjective colorimetry. It is considered that further studies are to be necessary to investigate quantitatively the subjective color distortion of near infrared absorbing lenses.

Analysis on Optical and Heat Blocking Characteristics of Near-Infrared Absorbing Lenses

Purpose : To analyze the optical and heat blocking characteristics of NIR absorbing lenses. Methods : To analyze definition, image test charts were photographed with a camera and the images were analyzed by image quality analyzing software. Visual acuity were measured on 32 subjects. To analyze heat blocking characteristics, the pig skin and eyelid were irradiated by NIR and their temperatures were measured by a digital thermometer and a thermal imaging camera. The lens surface temperature was measured after irradiating NIR on the lens, and the heat damage on the lens was analyzed. The subjective satisfaction with definition, glare, heat sensitivity and light perception was evaluated in condition wearing NIR absorbing lenses and tinted lenses. Results : There was no significant difference in definition and visual acuity between NIR absorbing lenses and tinted lenses. The temperature changes of pig skin and human eyelids when wearing NIR absorbing lenses were lower than when wearing tinted lenses. The NIR absorbing lenses irradiated by NIR showed higher surface temperature and was damaged more quickly than the tinted lenses irradiated by NIR. In the survey, the subjective satisfaction of the sharpness (p=0.040) and glare (p=0.000) caused by the NIR absorbing lenses were both higher than that of the blue lens, but there were no significant differences between the gray, brown and green tinted lenses. The subjective satisfaction of the heat sensation (p=0.040) and light quantity (p=0.000) by NIR absorbing lenses were higher than that of the tinted lenses. Conclusion : The sharpness and visual acuity of the NIR absorbing lenses and the tinted lenses were not significantly different, and the NIR absorbing lenses showed better heat blocking effect than the tinted lenses. It is considered that this study suggested the fundamental data on the heat blocking effect of the NIR absorbing lenses.

Could Modifying the Bagolini Glasses Improve the Reliability of Responses?

Aims:Bagolini striated lenses are a useful test of binocular vision, but the variations in the striations (frequency and thickness) can impact on the perceived image. Also, responses can be difficult to interpret in young children. Therefore, the aims of this project were to evaluate the impact of striation frequency and the addition of coloured filters on subjective responses.Methods:Three sets of striated lenses were made (small, medium and large striations), each produced in two forms (both lenses clear, or with a red and blue lens). Also, Bagolini glasses (Optiker Ryser) were used, with and without the addition of red and blue filters. Subjects were asked to report what they perceived, with subsequent questions regarding the number and length of lines.Results:Forty-two adult subjects were tested, with uniocular VA ranging from –0.18 to 1.10 logMAR (mean 0.08 ± 0.25). The number of lines seen when varying the line thickness did not vary between coloured and clear lenses (post-hoc analysis following ANOVA, p > 0.1 in all comparisons). Adding red/blue filters to the original Bagolini glasses did not alter the rates of subjects perceiving a cross (Chi-square, p = 0.8). However, the laser-cut lenses produced a significantly shorter light streak than the original lenses (One-way ANOVA, p < 0.001), but the colour of the filters made no difference to the length of streak perceived (Tukey’s Test, p = 0.20).Conclusions:The addition of coloured filters did not impact on the responses given to the original or laser-cut lenses, suggesting this modification may aid responses in children. However, further evaluation is required with finer striations and thinner lenses to improve the visibility of the lines.

A Mother's Reflection, and: Blank Canvas, Preferably

A Mother's Reflection, and: Blank Canvas, Preferably Shavanna Henry (bio) A Mother's Reflection Pass it to her before the storms force her inside.Let her hear your criesof joy and love that swarmsand never dies. Hand her the mirror that reflects your prideand reveals your shameless glow.Help her embrace the waves along her sidebefore the world tells her no. They'll tell her lies that sting her souland burn her flesh with bleach.Then, fill the void that you left wholeunless you stress your speech. Remember, you must: callous storms can't be defeateduntil self-love and appreciation are repeated. Blank Canvas, Preferably Add a speck of black to the corner of the page, then line the canvas with blue;blue lenses over my brown eyes, and a blue collar around my neck.Feed me your words of honey nectar,which is as smooth as the umber liquor you've sold me since I was two. Allow me to stand in the sun you've created with your fleshthat beams brighter than light; rightfully so, you believe.I wait for the resemblance to show,but the speck prevents our lanes from being sewn. Yet, in the center of the page, I anticipate being chosen by thee;the only one that could be worthy enough to make the selection, of course.I twirl my altered curls and cross my pale fingers in a dress that mimics yours, butto my displeasure, the edges of the canvas begin to peel as you wait with tapping heelsfor myself to be revealed. You cringed as I cried.I tried to wipe it down to a speck and not a half;a speck and not a quarter or an inch or enough to be smeared from one side to another.But a speck of black was too present on your canvas. With a stroke of neutral you blended the speck into the background—correcting the color—then straightened the edges.Back to the blank canvas I went, pretending that your name was mine, and you liked it.In fact,all was pleased,except me. [End Page 198] Shavanna Henry Shavanna Henry is a creative writer from California who specializes in literary fiction and young adult literature. She is currently completing a series of poetry, a fiction trilogy, and a memoir. Copyright © 2019 Shavanna Henry

The Change of Accommodative Functions by Difference Density and Color

Purpose : This study was to investigate the change of accommodative functions by different color density and color of colored lenses.Methods : Participant had a normal NPC and no dyschromatopsia, phoria and eye disease, also had no histories of eye surgery in 31 students of university. Their accommodative functions were measured according to 50%, 80% density of the gray, blue, brown lens and non-colored lenses. Tests of accommodative functions performed include amplitude of accommodation, accommodative facility, relative accommodation, and accommodative lag.Results : The amplitude of accommodation and accommodation lag were increased when wearing the colored lens. Negative relative accommodation was more increased when wearing the colored lens than achromatic. Positive relative accommodation increased when wearing the blue color lens density by 50%. Also, accommodation facility increased when wearing the colored lens, but, as the density of the color increased, the accommodation facility was decreased.Conclusion : As since the accommodation function changes according to density of the colored lenses, working distance and environment of the wearing colored lens should be considered when selecting density and color of colored lenses.

Zjawisko fotowrażliwości u dzieci i młodzieży z napięciowymi bólami głowy – jego objawy i sposoby zapobiegania. Doświadczenia własne

BackgroundEEG is one of the basic tests in neurological diagnostics. Photostimulation trial is considered to play an important role during the test. It bases on applying an intermittent light stimulus with the use of a stroboscopic lamp. The occurrence of EEG changes in response to photostimulation is called photosensitivity. AimEvaluation of the efficacy of a photostimulation trial in the activation of paroxysmal changes in EEG recordings in children and adolescents with tension headaches. The study also aimed to evaluate an influence of the use of glasses with Z1 lenses (Italian blue) on the reduction of the photosensitivity. Material and methodsThe analysis included 51 patients with tension headaches aged 5–18 years – 12 boys (23%) and 39 girls (76%) diagnosed with photosensitivity of I, II, III or IV type. All patients underwent EEG examination in accordance with medical indications (tension headaches). After the registration of a photosensitivity, in the course of the same study, the EEG recording was repeated with the use of glasses equipped with Z1 filter lenses. ResultsA complete or partial disappearance, or the reduction at least by half of a period or an amplitude of discharges with Z1 filter glasses compared to baseline examination was considered the criterion of an effectiveness of Italian blue lenses. A positive response was achieved in 41 patients (80%). Complete resolution of discharges was achieved in 26 patients (50%) and partial reduction was observed in 15 patients (29%). Ten patients did not respond to Z1 lenses. ConclusionThe use of Italian blue lenses allows to improve EEG recordings in a large percentage of pediatric patients with tension headaches. The use of Z1 lenses can be considered an effective alternative in the reduction adverse effects of the photosensitivity in children and adolescents.

3. Polarized and lens color effects on photoparoxysmal response

Introduction Approximately 5% of epilepsy patients’ photosensitivity can be detected on EEG recordings. This photoparoxysmal response (PPR) may prevent patients from performing their daily activities and also can result in seizures and anxiety. The objective of this study is to optimize the use of Z1 and other polarized and colored lenses for reducing PPR in epileptics. Purpose We propose that by covering central and temporal visual fields with either Z1 lenses plus side guards or elongated polarized lenses may suppress the PPR by altering the luminance and/or wavelength. Methods 22 pediatric patients with Type 4 PPR (Waltz et al.) were tested with and without Z1 lenses using photic stimulation from 1 to 21 Hz. 19 patients had primary generalized epilepsy (5 JME & 14 Absence), 2 had reflex epilepsy and 2 had Dravet’s Syndrome. Results Responses were classified into 3 groups: PPR disappearance, persistence or attenuation. 14 patients had reduced PPR (64%) and in 5 patients PPR disappeared (23%). 3 patients (13%) demonstrated persistence of the PPR with Z1 lenses. Several patients tested with side guards plus cobalt blue tint polarized lens sunglasses showed marked PPR reduction. Several patients tested with elongated polarized sunglasses covering the temporal visual field showed PPR attenuation. Placing a red lens over the photic stimulation lamp augmented the PPR from 1 to 19 Hz stimulation in several patients. A blue lens over the photic lamp resulted in attenuation or disappearance of the PPR at several photic stimulation frequencies in several patients. Conclusions Z1 and other blue lenses reduced the PPR in nearly all patients. Possible mechanisms include polarization, reduction of luminance, and filtering of red light. Further testing of photosensitive patients will be performed. Comparisons will be made between Z1, elongated polarized, cobalt blue, red and green Coppola, 2006 , Jeavons and Harding, 1975 , Newmark and Penry, 1979 , Binnie and Jeavons, 1992 , Quirk et al., 1995 , Kasteleijn-Nolst Trenit’e et al., 2002 , Takahashi and Tsukahara, 1976 .

Effects of lateralized light flash and color on unilateral neglect

Purpose: Bottom-up-based sensory stimulation has been useful in promoting recovery from post-stroke neglect. Light and color are salient stimuli for guiding our orienting behaviors and influence the degree of spatial bias. This study evaluated the effects of lateralized light flash and color on spatial bias in unilateral neglect (UN). Method: We enrolled 15 individuals with UN as a consequence of a right hemispheric stroke of less than 65 d. This was a 3 × 3 design study with three conditions of lens color (colorless, red, and blue) and three conditions of flash light locations (no flash, left, and right). Results: All participants showed a decrease in ipsilesional spatial bias under left-side light flash and a red lens. Right-side light flash and a blue lens induced more rightward bias than other conditions. Conclusions: This evidence confirms the use of sensory stimulation to complement post-stroke UN remediation. Lateralized light flash to the contralesional space and red-colored lenses have beneficial effects on amelioration of UN, whereas ipsilesional light flash and the color blue may exacerbate ipsilesional spatial bias in stroke survivors with UN.Implications for RehabilitationContralesional light flash and the color red may ameliorate ipsilesional spatial bias in stroke survivors with unilateral neglect (UN).Ipsilesional flash of light and the color blue may worsen ipsilesional spatial bias in stroke survivors with UN.

The effect of tinted spectacle lenses on contrast sensitivity and colour vision

Aim: Spectacle wearers often prefer tintedlenses to clear or non-tinted lenses for their protection against harmful radiation, improved cos-mesis, enhancement of visual performance and effects on colour vision. Among the available tinted lenses on the market blue, brown and grey tinted spectacle lenses are popular with varying gradesranging from A to D. Due to reduced transmission of light through such lenses, the optical system of the eyes and the environmental vision may be temporarily altered. Colour vision (CV) and con-trast sensitivity (CS) are important aspects of this altered visual world. This study investigated the effect of spectacle lenses of varying grades of tint on CS and CV.Method: The study adopted a pre- and postest research design and a sample of 90 participants were selected from the University of KwaZulu-Natal student population using convenience sam-ling. Each participant was screened for patholgy, dyschromatopsia, severe dry eyes (TBUT&lt;5 seconds), and the presence of any more than low metropia. Thereafter each successful participant was tested for CS and CV with their habitual precription and then tested randomly with a white clear) lens (placebo) and tinted (blue, brown, and grey) spectacle lenses made of CR39 material each having grades A, B and C over their habitual state. Light transmission was 85%, 75%, and 50% for grades A, B, and C respectively. The Functional Acuity Contrast Test (FACT) chart and American Optical Hardy, Rand, and Rittler (AO HRR) were used for the assessment of CS and CV respectively.Results: The data was analysed using the Statistical Package of Social Science (SPSS) version18. Compared to the habitual state, contrast sensitivity was enhanced with all the tinted lensesThe greater enhancement was for low spatial frequencies (LSF) and least for high spatial frequencies (HSF). With all tints Grade C had the least enhancement for very HSF. Many subjects showed no change in CV with any of the lensesused. The grey tint showed greater enhancement of CV as the density increases. Blue and brown tints showed a similar trend with grade B enhancing CV the most while grade C resulted in theleast reduction of CV.Conclusion: Grade A, B, and C of blue, brown and grey tinted spectacle lenses do not alter colour vision significantly but for the selected levels of transmission of the tints used, contrast sensitivity can be improved to some extent.

CFHTLenS: the relation between galaxy dark matter haloes and baryons from weak gravitational lensing

We present a study of the relation between dark matter halo mass and the baryonic content of host galaxies, quantified via luminosity and stellar mass. Our investigation uses 154 deg2 of Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) lensing and photometric data, obtained from the CFHT Legacy Survey. We employ a galaxy-galaxy lensing halo model which allows us to constrain the halo mass and the satellite fraction. Our analysis is limited to lenses at redshifts between 0.2 and 0.4. We express the relationship between halo mass and baryonic observable as a power law. For the luminosity-halo mass relation we find a slope of 1.32+/-0.06 and a normalisation of 1.19+0.06-0.07x10^13 h70^-1 Msun for red galaxies, while for blue galaxies the best-fit slope is 1.09+0.20-0.13 and the normalisation is 0.18+0.04-0.05x10^13 h70^-1 Msun. Similarly, we find a best-fit slope of 1.36+0.06-0.07 and a normalisation of 1.43+0.11-0.08x10^13 h70^-1 Msun for the stellar mass-halo mass relation of red galaxies, while for blue galaxies the corresponding values are 0.98+0.08-0.07 and 0.84+0.20-0.16x10^13 h70^-1 Msun. For red lenses, the fraction which are satellites tends to decrease with luminosity and stellar mass, with the sample being nearly all satellites for a stellar mass of 2x10^9 h70^-2 Msun. The satellite fractions are generally close to zero for blue lenses, irrespective of luminosity or stellar mass. This, together with the shallower relation between halo mass and baryonic tracer, is a direct confirmation from galaxy-galaxy lensing that blue galaxies reside in less clustered environments than red galaxies. We also find that the halo model, while matching the lensing signal around red lenses well, is prone to over-predicting the large-scale signal for faint and less massive blue lenses. This could be a further indication that these galaxies tend to be more isolated than assumed. [abridged]