This study was designed to assess the effect of nocturnal blue light exposure from LEDs on sleep and energy metabolism until next noon using polysomnography (PSG) and a room-size metabolic chamber, respectively. PSG, which measures EEG, chin EMG and eye movement, is the most popular method to evaluate sleep architecture, and it is used in clinical settings to diagnose sleep disorders and in sleep research to evaluate sleep quality. Usually, healthy people experience sleep cycles in 90-min intervals. Sleep consists of non-REM sleep and REM sleep. Non-REM sleep includes stage 1 and stage 2 (both light sleep) and slow wave sleep (deep sleep). Indirect calorimetry with a room-size metabolic chamber provides a controlled envi- ronment, in which energy metabolism can be continuously measured for a long period of time including sleep.
k bulbs were suspended, each covered by a sheet of co- extruded polycarbonate film (Rosco, Color Filter #74 Night Blue) that allowed light only in the blue portion of the spectrum to pass through. This apparatus was placed in the middle of the pen, with suspended bulbs reaching to approximately 6" from the ground to achieve maximal light exposure at eye level. Additionally, the pen was lined with 3' high reflective aluminum to ensure adequate blue light exposure in all areas of the pen. As a rabbit's gaze is typically 10 to 15 degrees below the horizontal plane, 3' high reflective aluminum was adequate to ensure contin- uous blue light exposure in the direction of gaze. All lights were connected to a timer that turned on at 11 am and turned off at 7 pm daily. Protective goggles were provided to all personnel entering the housing area during the PCNA Immunostaining comparing FFPE blue light exposed rabbit eyes to control eyes (O.D)
To more precisely determine the differential effects of light exposure level and duration on melatonin concentrations a series of normalizations were undertaken to minimize systematic differences among the nine subjects, between the two biomarker types (plasma and saliva), and among assay batches (Table 2). This approach was the same as that employed in the previous study by Figueiro and col- leagues , except for the additional normalization for assay batches. Although the assay methodology was not changed, the absolute melatonin concentrations differed systematically among the three batches sent for melatonin assays as revealed by examination of the saliva and plasma concentrations at 23:50 and 00:00, the two times, in the dark, common to all experimental sessions. First, the raw melatonin concentrations in a batch, either plasma or sal- iva, were averaged, and the ratio of the batch average con- centrations to the grand average concentrations were used to normalize the different batches for plasma and saliva concentrations. The same procedure was then followed to normalize differences among subjects. Thus, any systema- tic differences among batches, among subjects, and between plasma and saliva melatonin concentrations were minimized. The subject’s normalized melatonin concen- trations, both plasma and saliva, for every exposure dura- tion at a given retinal irradiance were then fitted with a polynomial equation using a least squares criterion. Each of those resulting normalized melatonin concentration curves, one for every subject at every retinal irradiance, including dark, were then adjusted to a common melato- nin concentration value at 00:00; the adjustment was based upon the reciprocal of the polynomial values at 00:00 for combined normalized plasma and saliva data. Table 2 Lighting conditions presented to subjects
Giant clams live in nutrient-poor reef waters of the Indo-Pacific and rely on symbiotic dinoflagellates (Symbiodinium spp., also known as zooxanthellae) for nutrients. As the symbionts are nitrogen deficient, the host clam has to absorb exogenous nitrogen and supply it to them. This study aimed to demonstrate light-enhanced urea absorption in the fluted giant clam, Tridacna squamosa, and to clone and characterize the urea active transporter DUR3-like from its ctenidium (gill). The results indicate that T. squamosa absorbs exogenous urea, and the rate of urea uptake in the light was significantly higher than that in darkness. The DUR3-like coding sequence obtained from its ctenidium comprised 2346 bp, encoding a protein of 782 amino acids and 87.0 kDa. DUR3-like was expressed strongly in the ctenidium, outer mantle and kidney. Twelve hours of exposure to light had no significant effect on the transcript level of ctenidial DUR3-like. However, between 3 and 12 h of light exposure, DUR3-like protein abundance increased progressively in the ctenidium, and became significantly greater than that in the control at 12 h. DUR3-like had an apical localization in the epithelia of the ctenidial filaments and tertiary water channels. Taken together, these results indicate that DUR3-like might participate in light- enhanced urea absorption in the ctenidium of T. squamosa. When made available to the symbiotic zooxanthellae that are known to possess urease, the absorbed urea can be metabolized to NH 3 and
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The objective measurements of light exposure were obtained over one week using Hobo light meters. It also was known light data logger, which was made by Onset Computer Corporation. The model used for this project was UA-002-64. It was very light, only 18gram, small (58 × 33 × 23 mm) and waterproof. It can measure tempera- ture and light and was used to record light intensity in lux every 2 minutes. The light data logger was worn dur- ing the waking hours over a week period. One light data logger was put outside and used as control to find out the time of sunrise and sunset. The light intensity gathered by light meter below 1000 lux was discarded and all above was considered as outdoor daytime data. 38.4256 lux was considered as travel indoor and 114.9723 was considered as outdoor travel. The unit of time was transformed from minutes to hours via dividing 30 as light meter recorded every 2 minutes. Then time spending outdoor, indoor, outdoor travel or indoor travel was calcu- lated. The light data logger was required to pin to their outer clothing with the light meter and temperature sen- sor facing outside all the time. It was required to wear all the time during waking hours.
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periods, bed curtains were taken away, and overhead room lights were contin- uously turned on. Exposure to either condition took place from enrollment until discharge at home. Light levels were measured throughout this period for 10 consecutive days by using an Actiwatch-L monitor (Cambridge Neu- rotechnology, Cambridge, UK) near the infant ’ s head (average light intensity levels for DL condition: day, 97.6 6 45.3 lux; night, 20.8 6 20.7 lux; average light intensity levels for CL condition: day, 499.3 6 159.2 lux; night, 28.5 6 27.5 lux). Daytime light exposure was signi ﬁ cantly different between the DL and CL condi- tions (P , .01, t test for independent variables). The lighting regimens were regularly checked by research assistants. After hospital discharge, no restrictions to lighting conditions were made.
Aspergillus niger and Trichoderma viridi were tested for its ability to degrade naphthalene after exposing to U.V light (30, 45, 60 min) by using solid mineral salts medium (SMS) with different concentrations 100, 300, 500 ppm of naphthalene. Results showed that 100ppm was the best concentration consumed by the fungal test then 300ppm and 500ppm and the results for secondary test by using Liquid Mineral Salts Medium (LMSM) 95% of degradation for 100ppm after 30 min of U.V. light exposure for Aspergillus niger while the results for Trichoderma viridi the best ratio for degradation was 97% for 100ppm after 30 min of U.V. light exposure.
Barilius vagrahas reached a position of importance in the hierarchy of class because of high abundance of protein and minerals. The effect of ultraviolet radiations on minerals, amino acid and fat content in fish, Barilius vagra was investigated at different time intervals (1 h, 11 h, and 21 h). It was observed that UV radiations have no significant effect on composition of minerals, but total crude fat, crude protein and nitrogen content decreases significantly with increase in exposure time of UV radiation. The decrease in percentage of crude fat, crude protein, and nitrogen, after 21 h of irradiation was found to be 3.621, 8.22 and 3.568 respectively. Also the amino acid content in fish scale observed to decrease on exposure to UV light and the maximum decrease was observed in Valine after 21 h of ultraviolet exposure. The exposure to UV light shows a reduction in the weight of powdered scale. Therefore, assimilation of a small quantity of small fishes can considerably enhance the biological value of the diet and subsidize to momentous advances in nutritional security.
14) when the homeostatic and circadian drives for wakefulness are high. We used videotracking assessment of immobility as a measure of sleep which has been found to highly correlate with EEG/EMG recordings of sleep. Opa1 +/+ and Opa1 +/2 mice exhibited low immobility-defined sleep (i.e. high activity) during the dark period of a normal 12:12 LD cycle as would be expected for a nocturnal species (Figure 4A). In response to the light pulse, a sharp increase in immobility-defined sleep was observed in both genotypes within 30 min of lights on (Figure 4B). Immobility levels subsequently declined to ,50% of baseline by the end of the light pulse. The sleep induction response differed from negative masking where the suppression in activity levels was maintained during the entire first hour of the light pulse. This adds further support to acute light induced sleep and negative masking being distinct processes. The latency to the first 2 min of continuous immobility (sleep latency) was not significantly different between genotypes (Figure 4C). During acute light exposure, the total time spent asleep was also not significantly different between wildtype and mutant mice (Figure 4D) suggesting that both genotypes sustained the inhibitory response to light.
The effect of light color or color temperature on the central and autonomic nervous systems has been exten- sively studied. According to Takahashi et al. , the con- clusions drawn from experimental studies can be divided into two categories: studies suggesting that red light has an arousing effect as opposed to the mitigating effect of the color blue [3,4,8,9], and studies suggesting that blue light has an arousing effect as opposed to the mitigating effect of the color red [2,10]. Despite the lack of consist- ent findings on this topic, some effect of light color on the CIZ is expected since body temperature is controlled by the central and autonomic nervous systems. There- fore, the present study tested the hypothesis that the CIZ changes in response to red and blue light exposure.
Although our findings are limited, the present study pro- vides application data that suggest that day-time exposure to a minimum dose of light can prevent LIMS even within just 1 day. These findings may be useful as humans adapt to artificial light environments in, for example, hospitals and underground shopping malls. Light-induced nocturnal melatonin suppression, however, depends on the duration of light exposure as well as the light intensity . The wavelength composition of nocturnal light also affects light- induced melatonin suppression [8, 33 – 35]. In addition, photosensitivity may be involved based on the basis of the person’ s eye colour  and ageing . Therefore, further research is needed to examine the parameters of light ex- posure and the photosensitive variation of human beings.
Abstract: The circadian system regulates the cyclical occurrence of wakefulness and sleep through a series of oscillatory networks that comprise two different theoretical processes. The suprachiasmatic nucleus (SCN) of the hypothalamus contains the master oscillatory network necessary for coordinating these daily rhythms, and in addition to its ability to robustly generate rhythms, it can also synchronize to environmental light cues. During jet lag, abrupt shifts in the environmental light–dark cycle temporarily desynchronize the SCN and downstream oscillatory networks from each other, resulting in increased sleepiness and impaired daytime functioning. Polysomnographic data show that not only does jet lag result in changes of sleep–wake timing, but also in different aspects of sleep architecture. This type of circadian misalignment can further lead to a cluster of symptoms including major metabolic, cardiovascular, psychiatric, and neurological impairments. There are a number of treatment options for jet lag involving bright light exposure, melatonin, and use of hypnotics, but their efficacy greatly depends on their time of use, the length of time in the new time zone, and the specific circadian disturbance involved. The aim of this review is to provide mechanistic links between the fields of sleep and circadian rhythms to understand the biological basis of jet lag and to apply this information to clinical management strategies.
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We obtained averaged ERGs using an evoked response recorder (PuREC, Mayo Co., Aichi, Japan) with a pulse reference power line noise reduction (PURE) method [39, 40] and skin electrodes from 90 artifact-free ERG signals. The active skin electrode was placed on the or- bital rim 7 mm from the margin of the lower eyelid of the left eye, and the reference electrode was placed on the same position on the right eye. The earth electrode was attached to the left earlobe. ERG signals were digi- tized at 1250 Hz and amplified with a digital band-pass filter of 0.3 – 200 Hz. From the averaged ERG, we ana- lyzed the amplitude of a wave, b wave, and photopic negative responses (PhNRs) (Fig. 4). The a wave ampli- tude was calculated as the maximum value of 10 – 50 ms after the light exposure minus the baseline average. The b wave amplitude was measured from trough of the a wave to the peak of the b wave located in 20 – 60 ms after the light exposure. The b/|a| was obtained as the b wave amplitude divided by the absolute value of the a wave (|a|). The PhNRmax was then calculated as the max- imum negative value of 40 – 200 ms after the light expos- ure minus the baseline average.
Adult Tridacna squamosa Lamarck 1819 (mass=500±180 g, N=42) were procured from Xanh Tuoi Tropical Fish (Ho Chi Minh City, Vietnam). The giant clams were maintained in tanks as described by Ip et al. (2015) but with slight modifications. The water temperature was maintained at 26±1°C, the salinity was 30 – 32 and the pH ranged between 8.1 and 8.3. The carbonate hardness was 143 – 179 ppm and the calcium concentration was 280 – 400 ppm. Each tank was illuminated from the top by two sets of Aquazonic T5 lighting systems (Yi Hu Fish Farm Trading, Singapore), and each system consisted of two sun and two actinic blue fluorescence tubes (39 W each). Using a Skye SKP 200 display meter connected with a SKP 215 PAR Quantum sensor (Skye Instruments, UK), the light intensity at the level of the giant clams was determined as ∼ 100 μ mol m −2 s −1 . Institutional approval was not necessary for research on giant clams (National University of Singapore Institutional Animal Care and Use Committee).
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The human eye automatically adapts to changes in light so that white subjects appear white even under different lighting conditions. Cameras that use film have to adjust for these differences by using color-correcting filters or switching to different film types. Digital cameras rely on software to correct the color temperature by determining white as the basis for the colors in the subject, then correcting the other colors to achieve a natural color range. < > mode automatically selects the white balance according to the light source where you are shooting. If this does not produce pictures with satisfactory coloring, you can select a mode other than < >.
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We consulted with academics working in the field of ALAN and animal behaviour to help formulate the main and secondary question and then define the scope of the systematic map. It was agreed to include behavioural effects of ALAN at night where there was a difference in intensity between day-time and night-time light (exclud- ing effects of constant bright light), but not behavioural impacts on humans. Additional stakeholder engagement to inform the parameters of the literature to be captured, will be undertaken before the map is undertaken with: academics working the field of Urban Planning; industry consultants working in Sustainability Planning; and, Fed- eral, State and Local Government Sustainability Planners. This systematic map will consolidate the evidence for the importance of ALAN as a pervasive form of environ- mental pollution which affects behaviour across taxa. It will inform future research into the effects of ALAN, aid decision making of urban lighting strategies and direct conservation initiatives to maintain wildlife stability and diversity in the face of global increases in the intensity and spread of artificial light at night.
light is considerably narrower than in birds, ending at ~450·nm (Phillips and Borland, 1992), in contrast to 565·nm in birds. The most important difference between the two groups, however, concerns the behaviour under long-wavelength light: from 500·nm onwards, the headings preferred by the salamanders shifted by ~90° counterclockwise with respect to those recorded under white light (Phillips and Borland, 1992; Deutschlander et al., 1999b). Salamanders that were kept under long wavelengths and had a chance to establish the shoreward direction under these light conditions preferred the true shoreward direction under red light but showed the reverse 90° shift when tested under white light. These observations seemed to imply that the directional information perceived under long- wavelength light differed from that under white or blue light. The authors speculate about two antagonistic spectral mechanisms indicating directions perpendicular to each other (see also Phillips and Deutschlander, 1997; Deutschlander et al., 1999a). At 475·nm, where both mechanisms would be equally stimulated, the salamanders were disoriented (Phillips and Borland, 1992). To reconcile this finding with the normal orientation observed under white light, where both mechanisms are likewise activated, Phillips and Deutschlander (1997) postulate that the short-wavelength part of the spectrum produces a stronger stimulus that dominates under full- spectrum light. Still, one would normally argue that a
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constantly bathed in sunlight. Both direct (skin- mediated) and indirect immunomodulation have been described. Visible light (400–700 nm) can penetrate the epidermal and dermal layers and directly interact with circulating lymphocytes. UV-B and UV-A radiation alter normal human immune function predominantly via a skin-mediated response . Epidermal Langerhans cells survey invading agents and transmit the information into immune cells. After engulﬁ ng exogenous antigen, these sentinels migrate to draining lymph nodes and present the processed antigen to T cells, thereby inducing speciﬁ c T cell diﬀ erentiation and T cell activation. Ionizing and non-ionizing UV radiation (below 400 nm) inhibit this antigen presentation via induction of suppressive keratinocyte-derived cytokines. Th is reduces eﬀ ector T cell proliferation and activity and induces immuno- tolerance . In addition, regulatory T cells (Treg) serve important immunoregulatory and immunosuppressive functions. Induced by UV radiation, Treg cells release IL-10, leading to immunosuppression. Th us, functional alterations of epidermal Langerhans cells and a systemic increase in Treg cells couple the epidermis to local and systemic immunosuppression . Th e balance between the numbers and function of regulatory and eﬀ ector T cells is crucial for the immune system. Although the
The results in (Table 3) showed that exposure to UV light caused increasing the concentrations of secondary metabolites in most treatments than the mother plant but these increases were not signification in all compounds except agoene which scored a significant increase reached (37.61) mg when exposed to UV light for 10 minutes.
Natural vitamin A in whole milk was more stable to light than added vitamin A due to natural vitamin A is found in milk fat globules whereas added retinyl palmitate is dispersed in the water phase of milk, which could be more prone to oxidation due to greater contact with oxygen (Thompson and Erdody, 1974). Vitamin D loss occurred at a rate much slower than other vitamins in milk. Using the same system of exposing milk samples in test tubes at the same light intensity of 300 ft-c, Gaylord et al. (1986) reported the rate constant for riboflavin loss was 0.0616 per hour and retinyl palmitate was 0.0298 per hour, whereas Renken and Warthesen (1993) reported the rate constant for vitamin D loss was 0.0009 per hour. Chocolate milk products also have reduced vitamin A degradation, either due to protection by carrageenan alone or in combination with chocolate color and/or flavor. Vitamin A protection in chocolate milk is due to increased light scattering by the additional particles. Chocolate flavor components of chocolate milk can also reduce development of light-oxidized off-flavors (Chapman et al., 1998). These findings demonstrate that exposure of fluid milk to light can adversely affect both flavor quality and nutritional value of fluid milk products.
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