A lighting evaluation of a facility for the elderly

A residential facility for the aged was evaluated for their illumination needs. Only the shared facility and grounds immediately surrounding it were considered. The facility evaluated is one of the most modern and the lighting design is considered its best feature. The age of residents occupying the facility ranges from 60 to 85 years. The lighting evaluation included administering a lighting adequacy/inadequacy questionnaire and measurement of actual light levels in the various parts of the facility during the day and after dark hours. The results indicated that lighting in approximately half the areas surveyed was substandard. An attempt to develop recommendations for the lighting needs of the elderly was unsuccessful. It was concluded that realistic illumination level recommendations need to be developed for the elderly.     

Chick pineal serotonin acetyltransferase: a diurnal cycle maintained in vitro and its regulation by light.

We have reproduced in vitro the diurnal cycles in levels of serotonin acetyltransferase activity found in the chick pineal gland in vivo. The more closely the lighting conditions of culture matched those under which the birds were raised, the closer was the similarity between cycles in levels of enzyme activity in vitro and in vivo. Repetitive cycles in levels of acetyltransferase activity persisted in culture for at least 4 days under a diurnal cycle of illumination, and at least 2 days in continuous darkness. When glands were explanted into culture in the light phase of a cycle, short periods of further exposure to light markedly stimulated subsequent increase of acetyltransferase in the dark (after a short lag). Prolonged exposure to light in culture markedly inhibited increase of enzyme activity. Cycles in the levels of enzyme activity in glands cultured under altered light cycles were regulated primarily by changes in illumination. However, the endogenous biological 'clock' remained at least partly entrained to the original light cycle. Increase of acetyltransferase activity in vitro was markedly stimulated by theophylline plus compound Ro. 20.1724 (4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone) under all lighting conditions. Kinetics (to the time of attaining maximum levels in situ) of the increase under diurnal lighting and in constant darkness were indistinguishable from those in vivo. A high concentration of dl-propranolol markedly stimulated an increase in acetyltransferase activity in glands cultured in constant darkness but had little effect on glands under diurnal lighting or continuous illumination.     

Diurnal lighting patterns and habitat alter opsin expression and colour preferences in a killifish

Spatial variation in lighting environments frequently leads to population variation in colour patterns, colour preferences and visual systems. Yet lighting conditions also vary diurnally, and many aspects of visual systems and behaviour vary over this time scale. Here, we use the bluefin killifish (Lucania goodei) to compare how diurnal variation and habitat variation (clear versus tannin-stained water) affect opsin expression and the preference to peck at different-coloured objects. Opsin expression was generally lowest at midnight and dawn, and highest at midday and dusk, and this diurnal variation was many times greater than variation between habitats. Pecking preference was affected by both diurnal and habitat variation but did not correlate with opsin expression. Rather, pecking preference matched lighting conditions, with higher preferences for blue at noon and for red at dawn/dusk, when these wavelengths are comparatively scarce. Similarly, blue pecking preference was higher in tannin-stained water where blue wavelengths are reduced. In conclusion, L. goodei exhibits strong diurnal cycles of opsin expression, but these are not tightly correlated with light intensity or colour. Temporally variable pecking preferences probably result from lighting environment rather than from opsin production. These results may have implications for the colour pattern diversity observed in these fish.     

Primate Location Preference in a Double-Tier Cage: The Effects of Illumination and Cage Height

Nonhuman primates are frequently housed in double-tier arrangements with significant differences between the environments of the upper and lower-row cages. Although several studies have investigated whether this arrangement alters monkeys' behavior, no studies have addressed the two most notable differences, light and height, individually to determine their relative importance. This experiment examined how rhesus and long-tailed macaques allocated their time between the upper and lower-row cages of a 1-over-1 apartment module under different lighting conditions. In Condition A, monkeys' baseline degree of preference for the upper- and lower-row was tested. In Condition B, the lighting environment was reversed by limiting illumination in the upper-row cage and increasing illumination in the lower-row cage. In both conditions, monkeys spent more time in the upper-row cage, thus indicating a strong preference for elevation regardless of illumination. The amount of time that monkeys spent in the lower-row cage increased by 7% under reversed lighting, but this trend was not significant. These results corroborate the importance of providing captive primates with access to elevated areas.     

Spectral properties of light affect plasma and pituitary gonadotropins in male rats

In order to find out whether different light spectra have any role in regulating the gonadotropin levels in male rats, we compared the 24-hour patterns of plasma and pituitary gonadotropins in rats kept for 7 days in natural or in cool white artificial lighting (exp. I). The intensity and periodicity of the two lighting conditions were adjusted as similar as possible. Further, we measured plasma and pituitary gonadotropins in the middle of the light period and in the middle of the dark period in rats kept for 7 days under artificial lightings of three different spectra (exp. II). In both experiments, in all lighting conditions we found higher plasma levels of LH and FSH during the dark than the light period. The differences were statistically significant only when the illumination contained more long and/or short wavelengths than the usual cool white laboratory lighting. The pituitary contents of gonadotropins were not found to vary with the periodicity of lighting. In the 24-hour patterns the overall plasma levels were higher and the pituitary contents of gonadotropins lower in natural lighting than in cool white lighting. It was concluded that the spectral properties of light influence the secretion of gonadotropins in male rats, but the mechanism involved remains to be clarified.     

The influence of taste stimuli and illumination on electrogastrogram measurements

An electrogastrogram (EGG) is considered to be an index to the autonomic nervous system of the digestive organs. In the present study, we attempted to clarify whether or not an EGG can be used to evaluate the influence of illumination, and what kinds of effect taste stimuli and illumination have on the autonomic nervous system. In this study, we used the ratio of the normal wave component of the EGG (EGG-NR: 2-4.5 cpm power/1-10 cpm power) and the amplitude of a normal wave (EGG-NI: integrated EGG of 2-4.5 cpm). Thirteen healthy males participated in 16 experimental conditions (4 lighting conditionsx4 taste stimuli). The four lighting conditions were set by combinations of illuminance levels of 200 and 1500 lx and color temperatures of 3000 and 7500 K. The four taste stimuli were sweet (glucose), salty (salt), sour (acetic acid), and bitter (quinine). The changes in EGG-NR and EGG-NI were compared for different taste conditions. The results showed that EGG-NI was not significantly affected by the different taste conditions. However, the main effect of taste on EGG-NR was significant: sweet and salty tastes were significantly higher than the bitter taste. EGG-NR and EGG-NI in different lighting conditions were also compared. The main effect of different color temperatures was also significant, but the illuminance level did not affect EGG-NR. EGG-NR increased significantly at the lower color temperature. On the other hand, EGG-NI significantly increased at the lower illuminance. These results suggest that parasympathetic nervous activity has a predominant effect on gastric activity in different lighting environments. Therefore, EGG measurements may be useful indicators for illumination environment studies.     

Influence of illumination on autonomic thermoregulation and choice of clothing

This study was conducted to investigate how different levels of illumination below 1,000 lx would affect the autonomic and behavioral temperature regulation of humans. Seven healthy college-aged women (20+/-0 years) volunteered to participate in this study. They were exposed to a temperature of 26 degrees C in 320 lx for 30 min ('Equilibrium') followed by 700 lx or 70 lx for 30 min (stage 1). After stage 1, they were exposed to 20 degrees C for 30 min in the same illumination as in stage 1 (stage 2). In stage 2 the subjects were instructed to select and wear the clothing they needed for their thermal comfort. The data obtained were analyzed by paired t-test and repeated measures of analysis of variance. Forearm skin blood flow tended to remain steady in 700 lx but decreased markedly in 70 lx in stage 1. There were no significant differences between subjective thermal responses of the subjects experiencing 700 lx or 70 lx in both stages although the subjects felt cooler in stage 2 than in stage 1. The subjects were likely to prefer wearing heavier clothing in 70 lx than in 700 lx. It was concluded that vasoconstriction in the upper limbs occurred more strongly in dim light, which might result in different clothing preferences in a cool environment from those associated with brighter light intensity.     

Contemporary Knowledge of Dye Plant Species and Natural Dye Use in Kurdish Autonomous Region, Iraq

Contemporary knowledge of dye plant species and natural dye use in Kurdish Autonomous Region, Iraq In Kurdistan, natural dyes once played an important role in the life of nomads as they wild-crafted and traded natural dyes for their survival. They learned from their family how to find, harvest, process, and dye with natural dyes. Abandonment of weaving and the nomadic life, and recent changes in the economy have contributed to significant changes in the natural dyeing culture. Traditional knowledge of natural dyeing plants is no longer common among weavers. This study documents the surviving knowledge of dye plant species and assesses the transmission of knowledge between elderly weavers and a younger generation of weavers’ apprentices. Information on dyeing and dyeing plants was elicited through a species recognition task using picture cards, a pile-sorting task, and through in-depth interviews with nomads in the mountains of the Soran district as well as weaving teachers and students in the city of Erbil, Kurdish Autonomous Region, Iraq. Consensus analysis of pile-sorting data supports the hypothesis that informants belong to a single culture. The results confirm the erosion of natural dyeing culture in Kurdistan and stress the need to stimulate knowledge transfer from the elderly, empirical generation to the younger, learning generation. The study also uncovered the existence of a keen interest among the student informants in traditional herbal medicine. If this trend is true for Kurdish urban youth in general, then it could lead to a revival and perpetuation of traditional plant knowledge.     

Aspects of thermal preferences in housing in a hot humid climate,with particular reference to Darwin,Australia

This paper presents findings of a study of thermal discomfort and preferences in housing in the humid tropics. The study was conducted in Darwin, Australia. Thirty-one households, approximately half with fully airconditioned houses and half without airconditioning, were involved in the study. Data were collected by interviews, which covered topics such as use patterns of airconditioners and attitudes to airconditioning; and by comfort vote loggers, electronic devices which record temperature and humidity, and house-occupants' clothing and activity levels, experience of air movement, and vote on a thermal discomfort scale.Findings illustrate that mathematical models of thermal sensation, such as Gagge's DISC and the International Organization for Standardization's predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD), are of limited use as aids in the prediction of thermal preferences in Darwin housing. For example, they cannot answer the important question of whether or not airconditioning is necessary. A major reason for this limited usefulness appears to be the lack of any predictable relationship between thermal preference and thermal discomfort or thermal sensation.     

Ergonomics in traditional Iranian industries.

It is an acknowledged fact that Iranian carpet weavers are subject to excessive fatigue. Earlier investigation has shown this to be largely due to a non-ergonomic body position while working at a traditional loom. It would appear that significantly increased production could be achieved by eliminating or reducing this fatigue. An Iranian engineer has attempted to do this by inventing a metal loom which takes ergonomic factors into consideration. The purpose of this study was to evaluate the effect of the new loom by comparing the productivity of two groups in Kerman, Iran: one using the new ergonomic loom and the other using the traditional loom. In preliminary investigations various factors were taken into account so that the two groups might be considered comparable. After several observations the average productivity of each weaver was calculated (according to knots per day). The results showed that the ergonomic loom had the highest productivity figures for both sexes and that increased productivity was directly related to the degree of comfort of the carpet weavers.     

What weta want: colour preferences of a frugivorous insect

Plants use colours as signals to attract mutualists and repel antagonists. Fleshy-fruits are often conspicuously coloured to signal different types of information including fruit maturity and spatial location. Previous work on fruit colour selection focus on large diurnal vertebrates, yet fruit colours are perceived differently by frugivores with different types of visual systems. Here, we tested whether a nocturnal, frugivorous, seed-dispersing insect selects fruits based on their pigmentation and whether different lighting conditions affect fruit colour selection. We captured 20 Wellington tree weta (Hemideina crassidens) from a forest reserve on the North Island of New Zealand and brought them into laboratory conditions to test their fruit colour preferences. The fruits of Coprosma acerosa, a native shrub species that naturally produces translucent, blue-streaked fruits, were dyed either red or blue. Fruits were then offered to weta in a binary (y-maze) choice test in two light conditions, either at night during a full moon or under artificial light conditions in the lab. Weta preferred unmanipulated, naturally blue-streaked fruits and artificially-blue coloured fruits over those dyed red. Furthermore, their colour preferences were unaffected by light environment. Our results therefore suggest that weta can discriminate between colours (using colour vision) in both light and dark light environments. Their consistent preferences for colours other than red indicate that weta might be responsible for the unusual colours of fleshy-fruits in New Zealand.     

Subjective comfort vote and air temperature as predictors of performance in factory workers

Volunteer factory workers performed a series of tests in a mobile climate laboratory. The tests simulated factory skills and were performed at 6 degrees, 12 degrees, 18 degrees or 24 degrees C at low vapour pressures. At each temperature four groups of about 30 workers were tested: black men, and women and white men and women. A first order polynomial was used to fit the data for temperature and comfort vote. The comfort vote predicted about 6% of performance, temperature about 11%. On some manual tasks air temperature predicted more than 40% of performance. There were few differences between the groups.     

Air movement preferences observed in naturally ventilated buildings in humid subtropical climate zone in China

Occupants’ preferences for air movement in naturally ventilated buildings have been extracted from a database of three thermal comfort surveys conducted in the humid subtropical climate zone in China, during winter, spring, and summer seasons. The distribution of draft sensation shows that only 25.7, 38.5, and 28.7% of the subjects in winter, spring, and summer, respectively, felt that the available air movement was just right, suggesting that indoor air velocity may be a big problem in naturally ventilated buildings in humid subtropical China. Air movement preferences show that 15.8, 61.3, and 80.6% of subjects in winter, spring, and summer, respectively, wanted more air movement. Only a handful of subjects wanted less air movement than they were actually experiencing in any season, suggesting that draft was not much of an issue for thermal comfort. Occupants’ preference for air movement is strongly related to thermal sensation, showing that people want to control air movement as a means of improving their comfort. The demand for less air movement under cool sensation is much smaller than the overwhelming demand for more air movement when the sensation was warm. The above results indicate that air movement might have a significant influence over the respondents’ comfort sensation and that people required a high level of air movement in order to be comfortable during the summer season. Thus, one efficient way to improve the thermal environment in summer in humid subtropical China could be to provide occupants with effective natural ventilation and allow personal control of the air movement. Our findings are also applicable to other buildings, to encourage designers to provide air movement as a low energy cooling strategy and to ensure that sufficient levels of air movement are available.     

Low metabolic rates in primitive hunters and weaver spiders

The rates of oxygen consumption and carbon dioxide release of primitive hunters and weaver spiders, the Chilean Recluse spider Loxosceles laeta Nicolet (Araneae: Sicariidae) and the Chilean Tiger spider Scytodes globula Nicolet (Araneae: Scytodidae), are analyzed, and their relationship with body mass is studied. The results are compared with the metabolic data available for other spiders. A low metabolic rate is found both for these two species and other primitive hunters and weavers, such as spiders of the families Dysderidae and Plectreuridae. The metabolic rate of this group is lower than in nonprimitive spiders, such as the orb weavers (Araneae: Araneidae). The results reject the proposition of a general relationship for metabolic rate for all land arthropods (related to body mass) and agree with the hypothesis that metabolic rates are affected not only by sex, reproductive and developmental status, but also by ecology and life style, recognizing here, at least in the araneomorph spiders, a group having low metabolism, comprising the primitive hunters and weaver spiders, and another group comprising the higher metabolic rate web building spiders (e.g. orb weavers).     

A study on the prevalence of upper extremity repetitive strain injuries among the handloom weavers of West Bengal

Handloom is one of the oldest cottage industries in India, particularly in West Bengal, where a considerable number of rural people are engaged in weaving. Purposes of the present investigation were to clarify the prevalence of repetitive strain injuries in upper extremities among the handloom weavers and to identify the risk factors leading to its development. Fifty male handloom weavers were randomly selected from the population. A questionnaire (Kourinka et al., 1987) method including Borg scale assessment of pain, checklist analyses of the work, and time-motion studies for analyzing the repetitiveness/non-repetitiveness of the job were implemented. The time-motion analyses demonstrated that weaving occupied over 50% of the work cycle time for majority of subjects, and thus could be regarded as a repetitive activity. Statistical analyses revealed a highly significant correlation between the intensity of pain feeling and the repetitiveness on one hand, and the year of experience as a weaver on the other. By contrast, no significant relationship was observed between chronological ages of weavers and the pain intensity. These results suggested that highly repetitive works engaged for a long time could increase the intensity of the pain felt and would lead to repetitive strain injuries.     

Macronutrient Self-Selection Pattern in Rats under Different Lighting Conditions

The effect of constant darkness (DD) and constant light (LL) on the circadian pattern of macronutrient self-selection, daily food intake and body weight was analysed in rats using an automated computer system. No significant differences in energy intake were observed between groups as regards energy intake or macronutrient preferences. Fat and CHO intakes showed a negative correlation (p < 0.005 in LL and p < 0.0005 in DD and LD), while protein intake remained constant, which suggests the existence of separate regulation mechanisms governing the intake of protein and energy. Energetic requirements can be preponderantly covered by CHO or fat, depending on the preferences of the animal. Body weight measurements reflected no significant variations between groups at the end of the experiment. However, the circadian pattern of wheel-running activity and the intake of the three macronutrients measured in both constant lighting conditions varied with respect to that observed in LD. This was particularly true in the case of LL, when constant illumination exerted a decoupling effect on the rhythms. The results indicate that lighting conditions modulate the circadian pattern of wheel-running activity and macronutrient intake. However, changes in temporal organisation of food intake did not affect macronutrient preferences, daily energy intake, number of meals, feeding duration or body weight, suggesting the existence of a double, circadian and homeostatic, control of such variables.     

How to reduce the impact of artificial lighting on moths: A case study on cultural heritage sites in Slovenia

In an ever more artificially illuminated world, common moth behaviour, flight-to-light, causes declines in their abundance and diversity that can have severe impacts on ecosystems. To test if it is possible to reduce the number of moths attracted to artificially illuminated objects, the original lighting of 15 cultural heritage buildings in Slovenia was substituted with blue or yellow lighting. These three illumination types differed in the amount of luminance, percentage of UV and short-wavelength light which are known to affect flight-to-light of moths. During our three-year field study approximately 20% of all known moth species in Slovenia were recorded. The blue and yellow illumination type attracted up to six times less specimens and up to four times less species compared to the original illumination type. This was true for all detected moths as well as within separate moth groups. This gives our study a high conservation value: usage of alternative, environmentally more acceptable illumination can greatly reduce the number of moths attracted to artificially illuminated objects.     

The effect of testosterone on serum gonadotropins of castrated rats kept under different lighting conditions.

Testosterone feedback sensitivity was measured as the ability of testosterone propionate to decrease serum LH and FSH of long-term castrated (4 wk) rats under four different lighting conditions: periodic light (12L:12D), constant light (LL), constant darkness (DD), and dim night illumination (1 lx) with a 12L:12D photoperiod. Rats were exposed to the different lighting conditions for 1 wk, during which they received daily testosterone propionate (125 micrograms or 250 micrograms s.c.). At the end of the experiment the rats were decapitated at 1100 h, and serum gonadotropin levels were measured by RIA. Serum LH of the rats kept under LL was reduced to the level of the intact rats with the smaller testosterone dose (125 micrograms/day). Under all other lighting conditions only the large dose (250 micrograms/day) was able to restore the serum LH concentration to the level of the intact rats. Serum FSH was restored only partially, and the effect was the same with both doses and similar under all lighting conditions. We conclude that the increase in testosterone negative feedback sensitivity was not caused by the lack of periodicity of illumination alone, but that sufficient intensity of lighting throughout the 24 h was needed as well.     

Visual pecking preferences in domestic chicks. Part II. The role of experience in their maintenance or not.

The role of swallowing experience on the maintenance or switching of the basic visual preferences in the pecking of young chicks has been investigated using both visually attractive and less attractive seeds. It has been shown previously that chicks switch their preferences 24 hrs. later if they cannot swallow what they visually prefer whereas debeaked birds which are able to swallow large attractive seeds maintain their preferences. However, the same experiment made with glued seeds shows that the ability to swallow was responsible for the maintenance of preferences in debeaked birds. Swallowing appears to have a rewarding effect. The possibility of swallowing the visually preferred item seems to be the proximate factor which will determine whether experience reinforces basic visual preferences or, on the contrary, modify them.     

Pattern discrimination in a hawkmoth: innate preferences,learning performance and ecology

Spatial patterns are important cues for flower detection and recognition by nectar-feeding insects. Pattern vision has been studied in much detail in bees and flies but rarely in butterflies and moths. In this paper, I present a first proof of pattern-learning abilities in a moth, and discuss reasons for the limitations to their pattern learning. The diurnal hawkmoth Macroglossum stellatarum spontaneously prefers patterned to uniformly coloured stimuli but can be trained to choose the uniform stimulus. By contrast, experience does not override the innate preferences for radial over tangential patterns, and for tangential over striped patterns. These results do not reflect bad visual discrimination but rather a lack of learning ability and motivation to abolish innate preferences. I propose that radial and tangential flower patterns are good predictors of nectar reward, a condition under which learning is unlikely to evolve. These patterns serve not only as cues for flower detection but also as guides to the reward. Hovering pollinators strongly depend on these guides and should therefore: (i). have rigid pattern preferences; and (ii). not be motivated to abolish these preferences as easily as their innate preferences for colours.