Search

Safety from crime is a fundamental human need. In Maslow's hierarchy, safety is one of the foundational needs of well-being. The built environment should be safe to use at all times of the day and for all groups of people. After dark, the appearance of the outdoor environment changes dramatically, and this could impact the opportunities for crime. This study investigated the impact of daylight on the rates of different types of crime by comparing the crime rates during selected periods of daylight and darkness. The study used records of crime data from the Metropolitan Police Service. By studying crimes in the week on either side of the twice-yearly clock change, it is possible to compare periods that are dark in one week and light in the other at the same clock time. Where the time at which the crime took place was known, and using the GPS coordinates of the specific crime, the solar altitude was calculated and used to determine if it was light or dark at the time of the crime. A similar calculation was used to see if the crime would have been in the dark or light in the week on the other side of the clock change. The headline result is that there was 4.8% (OR 1.07) more crime in the dark periods than the light ones. However, this increase was not uniform across all crime types, and there were some further complications in some results due to potential changes in the behavior of some victims after dark. For the crimes of theft from a person and robbery of personal property, there was a significant increase during the dark period. The availability of light had an impact on the rate of certain crimes. Whilst this does not provide any information about the impact of street lighting on crime, it does provide some idea of by how much crime could be reduced if better lighting was provided. [ABSTRACT FROM AUTHOR]

Background: Currently, there is a paucity of guidelines relating to displays used for digital pathology making procurement decisions, and optimal display configuration, challenging.Experience suggests pathologists have personal preferences for brightness when using a conventional microscope which we hypothesized could be used as a predictor for display setup. Methods: We conducted an online survey across six NHS hospitals, totalling 108 practicing pathologists, to capture brightness adjustment habits on both microscopes and displays.A convenience subsample of respondents was then invited to take part in a practical task to determine microscope brightness and display luminance preferences in the normal working environment. A novel adaptation for a lightmeter was developed to directly measure the light output from the microscope eyepiece. Results: The survey (response rate 59% n=64) indicates 81% of respondents adjust the brightness on their microscope. In comparison, only 11% report adjusting their digital display. Display adjustments were more likely to be for visual comfort and ambient light compensation rather than for tissue factors, common for microscope adjustments. Part of this discrepancy relates to lack of knowledge of how to adjust displays and lack of guidance on whether this is safe; But, 66% felt that the ability to adjust the light on the display was important.Twenty consultants took part in the practical brightness assessment. Light preferences on the microscope showed no correlation with display preferences, except where a pathologist has a markedly brighter microscope light preference. All of the preferences in this cohort were for a display luminance of

Safety from crime is a fundamental human need. In Maslow’s hierarchy, safety is one of the foundational needs of well-being. The built environment should be safe to use at all times of the day and for all groups of people. After dark, the appearance of the outdoor environment changes dramatically, and this could impact the opportunities for crime. This study investigated the impact of daylight on the rates of different types of crime by comparing the crime rates during selected periods of daylight and darkness. The study used records of crime data from the Metropolitan Police Service. By studying crimes in the week on either side of the twice-yearly clock change, it is possible to compare periods that are dark in one week and light in the other at the same clock time. Where the time at which the crime took place was known, and using the GPS coordinates of the specific crime, the solar altitude was calculated and used to determine if it was light or dark at the time of the crime. A similar calculation was used to see if the crime would have been in the dark or light in the week on the other side of the clock change. The headline result is that there was 4.8% (OR 1.07) more crime in the dark periods than the light ones. However, this increase was not uniform across all crime types, and there were some further complications in some results due to potential changes in the behavior of some victims after dark. For the crimes of theft from a person and robbery of personal property, there was a significant increase during the dark period. The availability of light had an impact on the rate of certain crimes. Whilst this does not provide any information about the impact of street lighting on crime, it does provide some idea of by how much crime could be reduced if better lighting was provided.

Optimal lighting is an essential part of visual rehabilitation. Generally, lighting levels are assessed depending on the amount of light that is required to fulfil a task. However, it is equally important to assess tasks that rely on ambient lighting. This study compares two different methods to assess optimal ambient lighting levels for people with visual impairment. Two different methods were used. During the first method, the 3D Lightlab, subjects were seated on the side of a room and asked to describe which objects they detected and which objects they recognised in the room during increasing illumination levels. In the second method, subjects were asked the same question, but the room and the objects were projected on a screen with a beamer. Illumination levels were controlled using ND-filters. Illumination levels for optimal lighting are comparable for both Lightlabs. However, patients have a higher confidence level in the outcome of a 3D Lightlab. Although the 3D Lightlab is generally preferred by people with visual impairment, the 2D Lightlab is suitable for implementation in visual rehabilitation for clients who need to know their illumination levels for optimal lighting. [ABSTRACT FROM AUTHOR]

Ambient lighting has been identified as a motivationally relevant context that affects cognition, emotion, and behavior, including food consumption and choice. This study adds to this body of work utilizing optimal foraging theory, which predicts individuals will prefer foods that deliver the most energy while costing the least energy to obtain. The environmental contexts in which one will have to forage alter perceived energy expenditure. An experiment was performed in which young adults viewed food advertisements that varied in energy density level in either dim or bright contexts. Metrics assessing motivational activation and attitudes were obtained across and post exposure. Individuals exhibited greater motivational intensity and preference when exposed to more energy dense foods in light contexts, but preference dissipated in dark contexts. Less energy dense foods elicited more motivational preference in dark contexts compared to light. Self-reported attitudes and intentions were only affected by context. Thus, variations in lighting may have larger implications for food choice and overall health. [ABSTRACT FROM AUTHOR]

Preferred display luminance varies in relation to visual demand, image contrast, and ambient illumination. OLED is known to have a higher contrast ratio at a lower luminance output, and is more energy efficient at a lower luminance compared to LCD. To assess the preferred luminance in OLED and LCD in varied ambient lighting conditions, 48 young and older subjects were asked to perform reading, spreadsheet search, and videos viewing. They pre‐selected a preferred luminance level and then reassessed it after a 2‐min session for these tasks to arrive at a preferred luminance. Results show OLED has a lower preferred luminance compared to LCD, especially in bright viewing. Older viewers maintained a similarly higher luminance preference in dark and bright conditions, whereas young viewers preferred a lower luminance in dark viewing but not bright viewing. Conversely, pupil size was smaller in older viewers and in the bright condition. Image qualities were also better for the OLED, except brightness range and color vividness. These outcomes suggest lower OLED luminance is beneficial across age groups, ambient lighting, and task types, and can reduce energy consumption. [ABSTRACT FROM AUTHOR]

It has been suggested that much like commercial environments (e.g., retailing), the situational characteristics of gambling environments form an important determinant of gambling behavior. However, no research has examined whether ambient lighting in gaming venues can have unintended consequences in terms of gambling behavior. The results of three experimental laboratory studies show that game play duration and total spend increase when ambient lighting is dim (vs. bright). Process evidence suggests that this phenomenon occurs as ambient lighting influences risk-taking, which in turn increases game play duration and total spend. Further, evidence is provided that the effect of dim (vs. bright) ambient lighting reduces risk-taking and subsequent game play duration and total spend when an individual's self-awareness is facilitated (i.e., screening between gaming machines is removed). This research has implications in terms of public policy regarding the determination of minimum lighting levels in venues as a means to decrease gambling-related harm. Moreover, while gaming venues can use these insights and their ambient lighting switches to nudge individuals toward reducing their game play duration and total spend, gambling-afflicted consumers can opt for gambling venues with bright ambient lighting and those without screened gaming machines. [ABSTRACT FROM AUTHOR]

Monitor specification and viewing conditions are important factors affecting image assessment in mammography. This survey evaluates the different viewing conditions and monitor specifications that exist in acquisition and reporting rooms in UK breast screening units. Static (n = 10) and mobile (n = 2) breast screening units were evaluated in North West England. Room illumination levels were measured in 3 locations for each room using a calibrated Lux meter and the specification of 122 monitors recorded. Room layout, wall colour, location and number of doors, windows and light sources were recorded. In reporting rooms, 90/91 of monitors had similar technical specifications and were compliant to guidelines. The ambient light levels ranged from 10 to 25.8 lux. The mean illuminance was 12.32 ± 4.6 lux. In acquisition rooms, great variances appeared in monitor specification and ambient light levels. The majority of monitors (24/34) had 3 megapixel (MB) optimum resolution but the ambient light level ranged from 10 to 1020 lux. The mean illuminance was 105.3 ± 178.8 lux. The mobile units were consistent with each other and compliant with guidelines. A lack of consistency and great variances appeared in terms of ambient light levels and monitor specifications in the image acquisition rooms. However, there was excellent consistency among the illumination measurements and the monitors' technical specifications in the reporting rooms. This research demonstrates, for the first time, the need for further research and specialised guidelines for acquisition rooms. [ABSTRACT FROM AUTHOR]

Background: Currently, there is a paucity of guidelines relating to displays used for digital pathology making procurement decisions, and optimal display configuration, challenging.Experience suggests pathologists have personal preferences for brightness when using a conventional microscope which we hypothesized could be used as a predictor for display setup., Methods: We conducted an online survey across six NHS hospitals, totalling 108 practicing pathologists, to capture brightness adjustment habits on both microscopes and displays.A convenience subsample of respondents was then invited to take part in a practical task to determine microscope brightness and display luminance preferences in the normal working environment. A novel adaptation for a lightmeter was developed to directly measure the light output from the microscope eyepiece., Results: The survey (response rate 59% n =64) indicates 81% of respondents adjust the brightness on their microscope. In comparison, only 11% report adjusting their digital display. Display adjustments were more likely to be for visual comfort and ambient light compensation rather than for tissue factors, common for microscope adjustments. Part of this discrepancy relates to lack of knowledge of how to adjust displays and lack of guidance on whether this is safe; But, 66% felt that the ability to adjust the light on the display was important.Twenty consultants took part in the practical brightness assessment. Light preferences on the microscope showed no correlation with display preferences, except where a pathologist has a markedly brighter microscope light preference. All of the preferences in this cohort were for a display luminance of <500 cd/m 2 , with 90% preferring 350 cd/m 2 or less. There was no correlation between these preferences and the ambient lighting in the room., Conclusions: We conclude that microscope preferences can only be used to predict display luminance requirements where the microscope is being used at very high brightness levels. A display capable of a brightness of 500 cd/m 2 should be suitable for almost all pathologists with 300 cd/m 2 suitable for the majority. Although display luminance is not frequently changed by users, the ability to do so was felt to be important by the majority of respondents.Further work needs to be undertaken to establish the relationship between diagnostic performance, luminance preferences, and ambient lighting levels., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: David Brettle reports a relationship with Jusha Commercial & Trading Co, Ltd. that includes: consulting or advisory. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024 Published by Elsevier Inc. on behalf of Association for Pathology Informatics.)

Background: Hypoglycemia threatens cognitive function and driving safety. Previous research investigated in-vehicle voice assistants as hypoglycemia warnings. However, they could startle drivers. To address this, we combine voice warnings with ambient LEDs., Objective: The study assesses the effect of in-vehicle multimodal warning on emotional reaction and technology acceptance among drivers with type 1 diabetes., Methods: Two studies were conducted, one in simulated driving and the other in real-world driving. A quasi-experimental design included 2 independent variables (blood glucose phase and warning modality) and 1 main dependent variable (emotional reaction). Blood glucose was manipulated via intravenous catheters, and warning modality was manipulated by combining a tablet voice warning app and LEDs. Emotional reaction was measured physiologically via skin conductance response and subjectively with the Affective Slider and tested with a mixed-effect linear model. Secondary outcomes included self-reported technology acceptance. Participants were recruited from Bern University Hospital, Switzerland., Results: The simulated and real-world driving studies involved 9 and 10 participants with type 1 diabetes, respectively. Both studies showed significant results in self-reported emotional reactions (P<.001). In simulated driving, neither warning modality nor blood glucose phase significantly affected self-reported arousal, but in real-world driving, both did (F 2,68 =4.3; P<.05 and F 2,76 =4.1; P=.03). Warning modality affected self-reported valence in simulated driving (F 2,68 =3.9; P<.05), while blood glucose phase affected it in real-world driving (F 2,76 =9.3; P<.001). Skin conductance response did not yield significant results neither in the simulated driving study (modality: F 2,68 =2.46; P=.09, blood glucose phase: F 2,68 =0.3; P=.74), nor in the real-world driving study (modality: F 2,76 =0.8; P=.47, blood glucose phase: F 2,76 =0.7; P=.5). In both simulated and real-world driving studies, the voice+LED warning modality was the most effective (simulated: mean 3.38, SD 1.06 and real-world: mean 3.5, SD 0.71) and urgent (simulated: mean 3.12, SD 0.64 and real-world: mean 3.6, SD 0.52). Annoyance varied across settings. The standard warning modality was the least effective (simulated: mean 2.25, SD 1.16 and real-world: mean 3.3, SD 1.06) and urgent (simulated: mean 1.88, SD 1.55 and real-world: mean 2.6, SD 1.26) and the most annoying (simulated: mean 2.25, SD 1.16 and real-world: mean 1.7, SD 0.95). In terms of preference, the voice warning modality outperformed the standard warning modality. In simulated driving, the voice+LED warning modality (mean rank 1.5, SD rank 0.82) was preferred over the voice (mean rank 2.2, SD rank 0.6) and standard (mean rank 2.4, SD rank 0.81) warning modalities, while in real-world driving, the voice+LED and voice warning modalities were equally preferred (mean rank 1.8, SD rank 0.79) to the standard warning modality (mean rank 2.4, SD rank 0.84)., Conclusions: Despite the mixed results, this paper highlights the potential of implementing voice assistant-based health warnings in cars and advocates for multimodal alerts to enhance hypoglycemia management while driving., Trial Registration: ClinicalTrials.gov NCT05183191; https://classic.clinicaltrials.gov/ct2/show/NCT05183191, ClinicalTrials.gov NCT05308095; https://classic.clinicaltrials.gov/ct2/show/NCT05308095., (©Caterina Bérubé, Martin Maritsch, Vera Franziska Lehmann, Mathias Kraus, Stefan Feuerriegel, Thomas Züger, Felix Wortmann, Christoph Stettler, Elgar Fleisch, A Baki Kocaballi, Tobias Kowatsch. Originally published in JMIR Human Factors (https://humanfactors.jmir.org), 18.04.2024.)

Studies in chickens suggest low intensity ambient lighting causes myopia. The purpose of this experiment was to examine the effects of low intensity ambient lighting (dim light) on normal refractive development in macaque monkeys. Seven infant rhesus monkeys were reared under dim light (room illumination level: ~55 lx) from 24 to ~310 days of age with otherwise unrestricted vision. Refractive error, corneal power, ocular axial dimensions, and choroidal thickness were measured in anesthetized animals at the onset of the experiment and periodically throughout the dim-light-rearing period, and were compared with those of normal-light-reared monkeys. We found that dim light did not produce myopia; instead, dim-light monkeys were hyperopic relative to normal-light monkeys (median refractive errors at ~155 days, OD: +3.13 D vs. +2.31 D; OS: +3.31D vs. +2.44 D; at ~310 days, OD: +2.75D vs. +1.78D, OS: +3.00D vs. +1.75D). In addition, dim-light rearing caused sustained thickening in the choroid, but it did not alter corneal power development, nor did it change the axial nature of the refractive errors. These results showed that, for rhesus monkeys and possibly other primates, low ambient lighting by itself is not necessarily myopiagenic, but might compromise the efficiency of emmetropization. [ABSTRACT FROM AUTHOR]

The purpose of this systematic review was to establish the current status of recommended monitor specifications and viewing conditions in mammography for image acquisition and reporting rooms. A literature search was completed between August 2018 and March 2019 using ScienceDirect, PubMed, Web of Science and MEDLINE databases. An additional manual search was performed to identify relevant guidelines to support the review. Only articles and guidelines written in English were included. Results were selected according to the following criteria; articles detailing (i) monitor specification and, (ii) viewing conditions in mammography acquisition and reporting rooms. Twenty-one studies met the inclusion criteria. Six papers described monitor specifications, five described viewing conditions and ten guideline documents were identified from the UK, Europe and the US. Common outcomes were that monitors with 3 or 5 MP resolution seemed to be preferred and at the same time higher illumination levels (>15 lux) were found to decrease the luminance of the monitors and negatively impact the assessment of image quality. Contrary to this, the majority of guideline documents recommended illumination levels above 20 Lux. Finally, there is a lack of guidance for viewing conditions in acquisition rooms. This review did not reveal any strong evidence for the proposed room illumination levels in acquisition rooms. In reference to monitors specifications, there is preference for using higher resolution displays (3 and 5 MP) but again, the evidence is not strong. Moreover, variance exists in the guidelines and that promotes inconsistency in mammography departments. This review highlights the lack of standardised guidelines and the need for further research on the viewing conditions and monitor specifications for the acquisition rooms in mammography. [ABSTRACT FROM AUTHOR]

The emergence of ubiquitous sensing and the Internet of Things (IoT) have inspired the development of “smart” everyday objects, which offer tremendous opportunities for maintaining the quality of life in ambient assisted living (AAL) environments. Inspired by the future possibilities of connected everyday devices, we envision a peripheral activity-based awareness system that captures human activity information and renders this information to enhance context awareness and support social connectedness between the elderly and their caregivers. Leveraging ambient intelligence and IoT technologies, ambient displays can convey activity information in the periphery of our attention. In particular, light has been used as a means to display ambient information and there is scientific evidence that it can enhance well-being, interconnectedness, and improve productivity. In this paper, we undertake two studies, first through an exploratory study we investigate the features of light suitable for conveying subtle activity information within the periphery of the users' attention for promoting context awareness. Also, we examine the preferences, perceptions, and interpretations of ambient lighting configurations of prospective caregiver's for conveying the activity information of older adults. In a second study, we assess the implications of activity awareness through lighting on cognitive performance, moods, and social connectedness. The set-up and design decisions of the second study were partly informed by previous research and by the outcomes of the first experiment. Together, these studies provide additional design guidelines for representing activity information with ambient lighting and highlight potential benefits and usage possibilities for lighting displays within the AAL domain. Furthermore, the results indicate a significant effect of activity awareness on cognitive performance. However, there were no significant effects of activity awareness through lighting on moods and social connectedness. Finally, we discuss the design guidelines and implications of these findings for designing activity-based ambient lighting displays for AAL environments.

Astigmatisme merupakan kelainan refraksi dimana pembiasan pada meridian yang berbeda tidak sama akibat kelainan kelengkungan di kornea. Pada mata dengan astigmatisme lengkungan jari-jari pada satu meridian kornea lebih panjang daripada jari-jari meridian yang tegak lurus dimana dalam hal ini keluhan silau bisa terjadi jika kecerahan dari suatu bagian dari inferior jauh melebihi kecerahan yang berlebihan, baik yang terlihat langsung atau melewati pantulan. Tujuan penelitian ini adalah untuk mengetahui keluhan mata silau pada penderita astigmatisma dibandingkan dengan miopia. Desain penelitian ini adalah penelitian cross sectional dengan metode deskriptif untuk membandingkan ada atau tidaknya kesilauan pada penderita astigmatisma dibandingkan dengan penderita miopia. Sebanyak 68 orang mahasiswa dengan 34 orang penderita miopia dan 34 orang penderita astigmatisma. Hasil penelitian menunjukkan responden astigmatisma yang mengeluh silau berjumlah 28 orang (82,4%) dan yang tidak mengeluh silau berjumlah 6 orang (17,6%), sedangkan responden dengan karakteristik miopia yang mengeluh silau berjumlah 12 (35,3%) dan yang tidak mengeluh silau berjumlah 22 orang (64,7%), sehingga didapatkan kejadian silau 8,167 kali lebih besar pada astigmatisma dibandingkan dengan miopia. Prevalensi astigmatisma yang mengeluh silau (82,4%) dan miopia yang mengeluh silau (35,3%). Disimpulkan bahwa didapatkan keluhan mata silau yang lebih banyak pada astigmatisma dibandingkan dengan miopia. Astigmatisma is refraction disorder where deviation in the meridient is different because of curve disorder in cornea. In astigmatisma, half diameter of curve in one miridian cornea is longer than upright vertical of half diameter miridian. Ambient lighting can be hapened in astigmatisma is the bright inferior has been over lighting either direk vision or reflaktion. This research aims to know ambient lighting on astigmatisma compared by miopia suffere. The design in this reasearch is cross sectional by descriptive method to compare the ambient lighting in astigmatisma patient by myopia patient. The respondent is 68 students and 34 respondent are myopia patient, 34 respondent are astigmatisma patient. The result shows female respondents is 38 students (55,9%) and male respondent is 30 students (44,1%). The astigmatisma respondent are 34 students (50,0%) and myopia respondent are 34 students (50,0%), ambient lighting respondents are 40 students (58,8%) and the respondents who don’t have ambient lighting are 28 students (41,2%). Astigmatisma respondent who have ambient lighting are 28 students (82,4 %) and astigmatisma respondents who don’t have ambient lighting are 12 students (35,3%) and the respondents by myopia characteristic who don’t have ambient lighting are 22 students (64,7%). Astigmatisma prevalents by ambient lighting is 82,4 % and myopia by ambient lighting is 35,3%. It can be concluded that there is ambient lighting in astigmatisma more than myopia.

Abstract The purpose of this investigation was to determine the effects of narrow band, long-wavelength lighting on normal refractive development and the phenomena of lens compensation and form-deprivation myopia (FDM) in infant rhesus monkeys. Starting at 24 and continuing until 151 days of age, 27 infant rhesus monkeys were reared under long-wavelength LED lighting (630 nm; illuminance = 274 ± 64 lux) with unrestricted vision (Red Light (RL) controls, n = 7) or a +3 D (+3D-RL, n = 7), −3 D (−3D-RL, n = 6) or diffuser lens (From Deprivation (FD-RL), n = 7) in front of one eye and a plano lens in front of the fellow eye. Refractive development, corneal power, and vitreous chamber depth were measured by retinoscopy, keratometry, and ultrasonography, respectively. Comparison data were obtained from normal monkeys (Normal Light (NL) controls, n = 39) and lens- (+3D-NL, n = 9; −3D-NL, n = 18) and diffuser-reared controls (FD-NL, n = 16) housed under white fluorescent lighting. At the end of the treatment period, median refractive errors for both eyes of all RL groups were significantly more hyperopic than that for NL groups (P = 0.0001 to 0.016). In contrast to fluorescent lighting, red ambient lighting greatly reduced the likelihood that infant monkeys would develop either FDM or compensating myopia in response to imposed hyperopic defocus. However, as in the +3D-NL monkeys, the treated eyes of the +3D-RL monkeys exhibited relative hyperopic shifts resulting in significant anisometropias that compensated for the monocular lens-imposed defocus (P = 0.001). The red-light-induced alterations in refractive development were associated with reduced vitreous chamber elongation and increases in choroidal thickness. The results suggest that chromatic cues play a role in vision-dependent emmetropization in primates. Narrow-band, long-wavelength lighting prevents the axial elongation typically produced by either form deprivation or hyperopic defocus, possibly by creating direction signals normally associated with myopic defocus. Highlights In infant monkeys, narrow-band, long-wavelength lighting: • Produces axial hyperopia. • Prevents form-deprivation myopia. • Retards myopic compensation to imposed hyperopic defocus. • Augments hyperopia in response to imposed myopic defocus. Chromatic cues have powerful effects on ocular growth in primates. [ABSTRACT FROM AUTHOR]

This work concerns the subjective impression of perceived illumination. The purpose of the study is to test attributes expressing qualitative experiences referring to ambient lighting that can be applied as descriptors. Seventy participants viewed an actual model room, with the fourth wall removed (viewing booth). Walls, floor, and ceiling were achromatic. Two achromatic cubes were placed inside the room: One was a reflectance increment to the walls, the other a decrement. The room was illuminated by two different light sources, Artificial Daylight (D65) or Tungsten Filament (F), the order of which was randomized across participants. The participants' task was to evaluate ambient illumination for each light source. A semantic differential method was employed with 27 pairs of adjectives on 1 to 7 rating scales, categorized in three groups: characteristics of atmosphere, time, and cross-modal. Only the ratings of nine pairs of adjectives were not influenced by the type of illumination. The most differentiated couples under different illuminants were hot/cold and modern/old, but large differences also appeared with the following couples: hard/soft, technological/primitive, summery/wintry, warm/cool, sensual/frigid, natural/artificial, and hospitable/inhospitable. The hypothesis that there would be consistency among the subjects in evaluations of the characteristics tested and that these would be differently perceived under different illuminants was confirmed. The results show that it is possible to identify subjective perceived illumination as a phenomenon endowed with specific filling-in qualities and that as a perceptual experience it can be categorized, with implications for application in architecture and design. [ABSTRACT FROM AUTHOR]

A psychophysical experiment was carried out to investigate visual comfort for reading on an iPad under various illuminance levels, ranging from 50 lx to 1200 lx, in order to see whether and how the following variables can influence the visual comfort: observer's age, gender, the illuminance of ambient lighting, and the background colour in a document layout. A panel of 21 young and 22 older Taiwanese observers participated in the study. The paired comparison method was used for data collection and analysis. The experimental results show that for all lighting conditions, young observers tended to prefer reading documents that had a moderate CIELAB lightness difference between text and background, while older observers tended to prefer reading those with an extremely large lightness difference. The results also show that female observers tended to feel less comfortable than male observers when reading documents with an extremely large lightness difference. These findings were found not to be affected by the ambient illuminance. Regarding the influence of document background colour on visual comfort, the observers tended to feel more comfortable reading documents that had a gray background than reading those with a background colour of either white or black. It was also found that the visual comfort was slightly higher for positive polarity than for negative polarity, but the difference between the two settings was insignificant. [ABSTRACT FROM AUTHOR]

Dopamine is known to play an important role in the pathophysiological process of myopia development relevant to the ambient lighting, but it is still poorly understood about how lighting regulates dopamine and its interaction with dopamine receptors to mediate the pathogenic signal transduction leading to alterations of ocular globe and the pathogenesis of myopia. Many studies have highlighted changes of ocular dopamine amount in response to different lighting conditions, but little attention has been paid to the dopamine receptors during these processes. Here we examined the effects of different lighting exposures on the expression of dopamine receptors in rat R28 retinal precursor cells. R28 cells normally grown in dark were exposed to a low (10 lux) or high (500 lux) intensity of a source of LED white light (5000 K–6000 K) for 12 h and total RNA was isolated either immediately or after certain time continuous growing in dark. Both conventional and real-time RT-PCR were performed to determine the expression of all five different dopamine receptors in cells after treatments. While the transcripts of dopamine D2, D3, and D4 receptors were not detected in the total RNA preparations of all the cells, those of D1 and D5 receptors (DRD1 and DRD5) were induced by lighting in contrast to the dark control. Elevated levels of DRD1 and DRD5 mRNA returned back close to the original levels once the cells were maintained in dark after light exposures. Immunofluorescence microscopy using a specific antibody confirmed an increase in the immunoreactivity of DRD1 in the cells exposed to 500 lux lighting versus dark control. Notably, treatments of R28 cells with nanomolar dosages of dopamine (0–500 nM) directly downregulated expression of both DRD1 and DRD5, whereas haloperidol (0–50 nM), a DRD2 antagonist, significantly induced expression of DRD1. These results suggest that dopamine receptors in the retinal cells might actively respond to the environmental lighting to act as an important player in the activation of the dopaminergic system in the ocular structures relevant to the lighting-induced pathogenic development of myopia. [ABSTRACT FROM AUTHOR]

Lighting feedback may use colors that through their associations help users to easily process feedback messages and adapt their behavior. Study 1 showed more ease of processing (of feedback messages) only for participants receiving strongly -associated lighting feedback, as their processing times were not increased by additional cognitive load. Also, lighting feedback that was strongly associated with the message had stronger persuasive effects on behavior. Study 2 tested the effects of consistency of color association with the message. For example, while normally green is associated with low energy consumption, the inconsistent feedback condition showed green colors indicating high energy consumption. Results showed that only the inconsistent version of strongly -associated lighting feedback slowed down the processing of feedback messages. Also, consistent feedback had stronger persuasive effects on behavior. These findings increase our understanding of the psychological mechanisms of ambient persuasive technology showing the important role of strong and consistent associations of ambient lighting. [ABSTRACT FROM AUTHOR]

Using an RGB OLED display, we applied a paired comparison method to evaluate visual preference of OLED images and LCD emulations with varied backlight zone spacing and panel contrast. We also evaluated the impact of a glare source. Panel contrast was the strongest factor in determining image quality. [ABSTRACT FROM AUTHOR]

This paper investigates the cost of developing various daylighting strategies for a standard office building in relation to their ability to reduce electric lighting consumption. The reference building design for this study corresponds to a typical configuration that minimises the construction costs and is typical of the French market. We have compared scenarios that entail moving service spaces to the periphery, increasing ceiling height and adding light wells of various shapes. These special features increased the proportion of the indoor area with sufficient daylight by up to 40%, with an increase of construction costs ranging between 1.3% and 15.5% of the cost of the building. The extra cost of adding light wells was estimated at an average of €344 per work place, or €34 m −2 for a standard building with a distance between facades of 18 m. This value has to be compared with typical construction costs of €1500 m −2 . Payback time on investment based only on savings on lighting electricity appeared to be far too long (from 41 years to 540 years depending on the configuration tested) for this alone to justify the investment. However, benefits should be assessed in relation to the occupants’ well-being, safety in case of an electrical black-out, and rental and resell value. [ABSTRACT FROM AUTHOR]

An ultraviolet glow phenomenon of Lu 3 Ga 5 O 12 :Bi3+ phosphor is investigated in ambient lighting. In dark environment the phosphor exhibits ultraviolet persistent luminescence peaking at 313 nm, while in indoor ambient lighting the initial intensity of the ultraviolet emission is remarkably enhanced. Such an enhancement essentially originates from a photostimulation process upon stimulation by the polychromatic ambient light, revealing the role of ambient illumination in releasing the stored energy of the phosphor. The present study on Lu 3 Ga 5 O 12 :Bi3+ inspires us to revisit other ultraviolet phosphors, enabling more glow-in-the-ambient-lighting materials to be developed. • There is no spectral overlap between the glow emission and the ambient lighting. • The ultraviolet glow emission is remarkably enhanced in ambient lighting. • Illuminance and spectrum of the ambient light is crucial to the glow enhancement. [ABSTRACT FROM AUTHOR]

With the advent of high efficacy light emitting diode directional lamps as a key component in focal lighting, new possibilities emerge for re-designing the smart home scenario. A smart home scenario is characterized by enabled intelligent interworking of various wireless and wired technologies to provide inhabitants with ease of use of appliances, while creating a personalized and safe ambience space. More and more high and low data rate circulates within the indoor ambient space (e.g., home, hospitals, offices). Although, unlicensed technologies, such as wireless local area networks can take upon part of the indoor traffic, the ever increasing demand for such data, and users, calls for either use of licensed or novel unlicensed wireless communication technologies as part of the smart home enablers. This paper focuses on the potentials of visible light communications (VLCs), jointly with radio and fiber communications, to support very dense low and high data rate connectivity, while enabling deployment of secure-sensitive indoor applications, including indoor tracking and localization. The paper proposes a scenario for integrating VLC into the smart home scenario and a conceptual supporting architecture for its deployment. Further, the technical challenges and possible roadmap for the actual deployment are analyzed for the particular case of an eHealth scenario where the utilization of VLC technology is the enabler of the cost-efficient rollout of the required infrastructure and thus the game-changer in a multi-billion eHealth niche that is seeking for cost affordable solutions. [ABSTRACT FROM AUTHOR]

This study presents a digitally controlled LLC resonant dc-dc converter targeted to white LED luminaires in smart buildings. The module uses the LED array both for ambient lighting and for transmitting sensor data. Visible light communication is implemented with minimal incremental cost, by operating the LLC converter in burst mode, without causing any visible disturbance. The converter operates with a regulated average LED current, while the burst pulse timing is controlled to minimize the current disturbance and reduce the output capacitance. Variable pulse position modulation is used to modulate the data, while supporting a range of dimming settings. A digital demodulation scheme that supports variable frequency transmission is demonstrated. The 80 W, 340-400 to 23 V converter prototype has an efficiency of 95.1%. The bit error rate of the complete system is fully characterized versus distance and angle. [ABSTRACT FROM AUTHOR]

Liquid-crystal displays (LCDs) are used for displaying medical images under various illuminance conditions and with ambient-lighting colors. Our purpose in this study was to understand the variations of the chromaticity in LCDs under different fluorescent lighting conditions. The variation of chromaticity of LCDs at a white point consisting of equivalent pixel value in Red, Green, and Blue was examined under different types of fluorescent lighting. The direction of changes in the chromaticity diagram shifted to the color of each fluorescent lighting. When the differences in chromaticity (∆ u′ v′) increased, the observers' confidence levels in distinguishing color differences also increased. When the luminance of the LCD increased, observers' sensitivities for recognizing differences in chromaticity also increased as compared to observers' sensitivities at lower luminances. Our results indicate that observers recognized slightly yellowish colors even if ∆ u′ v′ was less than 0.01; thus, observers could perceive differences in chromaticity. These results could provide important and relevant information with regard to better ambient lighting conditions in an image-reading room. [ABSTRACT FROM AUTHOR]

Liquid-crystal displays (LCDs) with different types of surface treatment have been developed for decreasing the effect of ambient lighting on a displayed image. The effect of ambient lighting on LCDs with different surface treatments, namely, glare (G)-type, anti-glare (AG)-type, and anti-reflection (AR)-coating LCDs, was evaluated quantitatively in this study for appropriate selection. The effect of ambient lighting on diffuse reflection and specular reflection was investigated. The coefficient of diffuse reflection of the AR-coating LCD was smaller than the others. The effect of diffuse reflection on the display function of each LCD was evaluated in terms of the deviation of the contrast response at the lowest luminance level when the illuminance changed from the condition that was used for calibration of the grayscale standard display function. The display function of the AR-coating LCD was affected less by diffuse reflection compared to the others. On the other hand, the coefficient of specular reflection of the AG-type LCD was the smallest until the angle of aperture of the light source was 4.6°. The specular-reflected image on the AG-type LCD had a remarkably broad distribution compared to the others. Our results are merely examples for a limited number of LCDs; however, we clarified quantitatively that the AR-coating and the AG-type LCDs were affected less by diffuse and specular reflection than the G-type LCD. [ABSTRACT FROM AUTHOR]

Purpose: To determine the luminance and ambient lighting levels of x-ray film viewing boxes and viewing environments in X-ray facilities in the Cross River State of Nigeria in order to compare the results with existing international guidelines. Materials and methods: Eighteen (n=18) viewing boxes in nine hospitals were studied. Luminance and ambient lighting levels were measured using a factory calibrated Model 615 BK precision light meter. Measurements were made from small openings made at the centre and four corners of a thick black sheet of cotton fibre overlying the respective boxes. Measurements were made of the 17 points on each box, and the box mean, highest and lowest luminance, as well as average uniformity values determined. Respective viewing room ambient light levels were determined 30 centimeters (cms) from the viewing boxes surfaces with the boxes turned off. Values obtained were compared with those published in the literature, following the European Commission (EU), American College of Radiology (ACR), British Institute of Radiology (BIR), National Institute of Radiation Hygiene (NIRH), South African Directorate of Radiation (SADR), and World Health Organisation (WHO) guidelines. Results: Nine (50%) of the viewing boxes surveyed met the EU and WHO guidelines for uniformity and ambient light levels. All nine study centres met the ACR ambient light conditions, while 6% satisfied the SADR guidelines. Average brightness values of viewing boxes in the nine hospitals surveyed showed poor compliance with the published guidelines. Only one viewing box met the published minimum brightness value of 1500 cd m-2. Conclusion: The findings of this study highlight the need for quick intervention and adoption of quality control standards to improve radiographic viewing conditions in the state. This should facilitate optimal viewing conditions thereby enhancing accurate interpretation of conventional radiographic images. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: Recent research has provided evidence that in reading rooms equipped with liquid crystal displays (LCDs), a measured increase of ambient lighting may improve clinicians'' detection performance. In agreement with this research, the American College of Radiology (ACR) has recommended a moderate increase of ambient lighting in mammography reading rooms. This study was designed to examine the effect of a controlled increase of ambient lighting in mammography reading rooms on the diagnostic performance of breast imaging radiologists. Materials and Methods: Four breast imaging radiologists read 86 mammograms (43 containing subtle cancerous masses and 43 normal) under low (E = 1 lux) and elevated (E = 50 lux) ambient lighting levels on a Digital Imaging and Communications in Medicine–calibrated, medical-grade LCD. Radiologists were asked to identify cancerous masses and to rate their detection confidence. Observer areas under the curve (AUCs) were calculated using a receiver-operating characteristic analysis of fully paired results. Additionally, average observer selection times under both ambient lighting levels were determined. Results: Average radiologist AUCs decreased with elevated ambient lighting (0.78 ± 0.03 to 0.72 ± 0.04). Observer performance differences, however, were of the same order of magnitude as interobserver variability and were not statistically significant. Average selection times under increased ambient lighting remained constant or decreased, with the greatest decrease occurring for false-positive (20.4 ± 18.9 to 14.4 ± 9.6 seconds) and true-positive (18.0 ± 13.8 to 12.9 ± 9.4 seconds) selections. Conclusion: The results agree with those of previous studies in that observer performance differences under a controlled increase of ambient lighting are not statistically significant. On the basis of these findings and ACR guidelines, a moderate increase of ambient lighting in mammography reading rooms is still suggested, but further research with additional cases and observers should be considered. [Copyright &y& Elsevier]

Under typical dark conditions encountered in diagnostic reading rooms, a reader’s pupils will contract and dilate as the visual focus intermittently shifts between the high luminance display and the darker background wall, resulting in increased visual fatigue and the degradation of diagnostic performance. A controlled increase of ambient lighting may, however, reduce the severity of these pupillary adjustments by minimizing the difference between the luminance level to which the eyes adapt while viewing an image (Ladp) and the luminance level of diffusely reflected light from the area surrounding the display (Ls). Although ambient lighting in reading rooms has conventionally been kept at a minimum to maintain the perceived contrast of film images, proper Digital Imaging and Communications in Medicine (DICOM) calibration of modern medical-grade liquid crystal displays can compensate for minor lighting increases with very little loss of image contrast. This paper describes two psychophysical studies developed to evaluate and refine optimum reading room ambient lighting conditions through the use of observational tasks intended to simulate real clinical practices. The first study utilized the biologic contrast response of the human visual system to determine a range of representative Ladp values for typical medical images. Readers identified low contrast horizontal objects in circular foregrounds of uniform luminance (5, 12, 20, and 30 cd/m2) embedded within digitized mammograms. The second study examined the effect of increased ambient lighting on the detection of subtle objects embedded in circular foregrounds of uniform luminance (5, 12, and 35 cd/m2) centered within a constant background of 12 cd/m2 luminance. The images were displayed under a dark room condition (1 lux) and an increased ambient lighting level (50 lux) such that the luminance level of the diffusely reflected light from the background wall was approximately equal to the image Ladp value of 12 cd/m2. Results from the first study demonstrated that observer true positive and false positive detection rates and true positive detection times were considerably better while viewing foregrounds at 12 and 20 cd/m2 than at the other foreground luminance levels. Results from the second study revealed that under increased room illuminance, the average true positive detection rate improved a statistically significant amount from 39.3% to 55.6% at 5 cd/m2 foreground luminance. Additionally, the true positive rate increased from 46.4% to 56.6% at 35 cd/m2 foreground luminance, and decreased slightly from 90.2% to 87.5% at 12 cd/m2 foreground luminance. False positive rates at all foreground luminance levels remained approximately constant with increased ambient lighting. Furthermore, under increased room illuminance, true positive detection times declined at every foreground luminance level, with the most considerable decrease (approximately 500 ms) at the 5 cd/m2 foreground luminance. The first study suggests that Ladp of typical mammograms lies between 12 and 20 cd/m2, leading to an optimum reading room illuminance of approximately 50–80 lux. Findings from the second study provide psychophysical evidence that ambient lighting may be increased to a level within this range, potentially improving radiologist comfort, without deleterious effects on diagnostic performance. [ABSTRACT FROM AUTHOR]

Activities of daily living often require us to negotiate several obstacles in the travel path. To date, there is little work investigating how adults accomplish such tasks, and there is even less known about multiple obstacle avoidance strategies used by children. The current work will expand our knowledge about the role of vision in adults and children when avoiding two obstacles placed in their travel path under altered ambient lighting. Healthy 7-year old children ( n=10; aged 7.51±0.2 years) and adults ( n=10; aged 22.76±1.7 years) were instrumented with infrared markers (Optotrak, NDI) placed on anatomical landmarks and asked to walk along a ten meter path under three conditions: unobstructed, single obstacle, or double obstacle. These trials were performed under two lighting conditions: Full (simulating standard office lighting) and Low (simulating a dark hallway lit by nightlights). Data analyses included lead and trail clearance values, step length, step width and step velocity, take-off distance and Horizontal toe Displacement at Apex (HDA) which was defined as the distance between the horizontal position of the toe to the leading edge of the obstacle when the toe reaches its peak height. Adults were able to maintain consistent behaviour regardless of the number of obstacles in the travel path. Children, however, adjusted their foot placement for the second obstacle. This indicates that having multiple obstacles in the travel path is a more challenging task for 7-year old, and suggests that children at this age may not have fully developed anticipatory locomotor strategies. Children had larger clearance values than adults for the lead foot crossing the obstacle under all obstacle and lighting conditions, and consistently used larger HDA values than adults. Together, these findings suggest that children adopt more cautious strategies than adults in complex environments. Additionally, children decreased walking velocity, increased step width and decreased their step length in a Low light environment. These changes are all indicators of a more careful avoidance strategy, which implies that children at this age rely heavily on visual information to guide foot placements in a complex environment. [ABSTRACT FROM AUTHOR]

Abstract: In a typical conditioned place preference (CPP) preparation, animals alternately experience drug and vehicle effects in distinct chambers of an apparatus, spending more time in the drug-paired chamber post-conditioning. However, if all animals prefer the same chamber before conditioning, data interpretation may be compromised. Unbiased apparatus has been systematically validated with ethanol in mice ([Cunningham, C.L., Feree, N.K., Howard, M.A. Apparatus bias and place conditioning with ethanol in mice. Psychopharmacology (Berl) 2003;170:409–422]); the present study sought to identify and eliminate bias in a standard black-and-white apparatus and validate that apparatus for CPP with morphine and cocaine in rats. Apparatus bias was assessed in 24 adult female Sprague–Dawley rats. Subjects preferred the black chamber under bright lighting conditions, with no preference in the dark. Subjects then underwent a counterbalanced CPP regimen to 5 mg/kg SC morphine (n =12) or 20 mg/kg IP cocaine (n =12) using only tactile conditioned stimuli. Significant absolute preferences for the drug-paired chamber were produced by both drugs, with no effect of drug-paired chamber assignment on CPP expression; vehicle-treated controls (n =12) showed no preferences. Bias-free CPP to morphine and cocaine using standard apparatus in rats is possible. Implications for place conditioning are discussed, including the potential value of systematically exploiting apparatus bias in addition to eliminating it. [Copyright &y& Elsevier]

Previous work has demonstrated that the image variation of many objects (human faces in particular) under variable lighting can be effectively modeled by low-dimensional linear spaces, even when there are multiple light sources and shadowing. Basis images spanning this space are usually obtained in one of three ways: A large set of images of the object under different lighting conditions is acquired, and principal component analysis (PCA) is used to estimate a subspace. Alternatively, synthetic images are rendered from a 3D model (perhaps reconstructed from images) under point sources and, again, PCA is used to estimate a subspace. Finally, images rendered from a 3D model under diffuse lighting based on spherical harmonics are directly used as basis images. In this paper, we show how to arrange physical lighting so that the acquired images of each object can be directly used as the basis vectors of a low-dimensional linear space and that this subspace is close to those acquired by the other methods. More specifically, there exist configurations of k point light source directions, with k typically ranging from 5 to 9, such that, by taking k images of an object under these single sources, the resulting subspace is an effective representation for recognition under a wide range of lighting conditions. Since the subspace is generated directly from real images, potentially complex and/or brittle intermediate steps such as 3D reconstruction can be completely avoided; nor is it necessary to acquire large numbers of training images or to physically construct complex diffuse (harmonic) light fields. We validate the use of subspaces constructed in this fashion within the context of face recognition. [ABSTRACT FROM AUTHOR]

It has been suggested that low ambient lighting conditions increase the amplitude of the PERG, but no data has been available on this issue. We recorded the transient PERG (0.8° check size) and steady-state PERG (15 rev/s, 0.8° and 16° check size) under three lighting conditions: dark room, only illuminated by the stimulus (resulting in 30 lux), our standard room lighting (windows occluded, one lighted lamp, 200 lux) and fully lit room (full ceiling illumination with eight fluorescent tubes) resulting in rather bright 2300 lux. The stimulus luminance was 50 cd/m2. The sequence of lighting conditions varied for each subject and followed a balanced permutation of an ABCCBA scheme. Results showed a significant effect (P<0.01) across lighting conditions, with no relevant difference between the 30 and 200 lux conditions, but a reduction down to 70% at the 2300 lux condition. This obtained across all check sizes and temporal conditions. As an example, the transient PERG P50-amplitudes were as follows: dark, 5.6±0.8 μV; medium, 5.3±0.6 μV and bright, 3.8± μV (mean ± SEM). Peak times decreased significantly with illumination (dark, medium or bright): 45.9±0.9, 43.1±0.6 or 40.8±0.8 ms. Contrast measurements quantitatively explained the noticeable reduction of PERG amplitude at the brightest illumination level simply by straylight, which reduced the display contrast. This suggests that bright sunlight should be excluded, and that lighting conditions should be moderately standardized at low or medium luminance levels for reproducible amplitudes and peak times. [ABSTRACT FROM AUTHOR]