Although it is well known that ultraviolet and short wavelength visible rays are harmful to the human lens and the retina, consumers still tend to select sunglasses on the basis of fashion rather than protective quality. In order to provide guidelines for selecting appropriate sunglasses, we studied the mechanism of phototoxic damage and UV protective quality of commonly used sunglasses. Commonly used sunglasses were chosen by random sampling, and their UV transmittance was examined by spectrophotometer using neutral density filter method. UV transmittance was shown to be 3.0% to 40.8% and there was no significant relationship between UV transmittance and the tint or darkness of the sunglasses.
Darkness ; Humans ; Retina

The latent nystagmus seems to be absent when both eyes are open, but on covering one eye, bilateral jerky nystagmus is evoked with the fast phase toward the uncovered eye. The confirmed diagnosis of latent nystagmus can be made with the aid of the Electro-oculography (EOG). On EOG recording, we experienced a case of latent nystagmus in light, which showed the characteristics of infantile nystagmus in darkness.
Darkness ; Diagnosis ; Electrooculography

The results of rotation chair test were known to variable by many parameters such as eye opening and alertness, etc. The situational change in rotation chair test must be considered to interpretation of its result. But in Korea, there were no reports or articles about parameters which influence the result of rotation chair test. So, we assumed that eye opening and alertness were main parameters and took rotation chair test in neurotologically normal subjects. For evaluation of the effect of eye-open or eye-closure and alertness on the rotational vestibular stimulation, we have taken sinusoidal harmonic acceleration test in 30 otoneurologically normal subjects. The maximal slow phase eye velocity, gain and asymmetry were obtained and compared with each other in four different conditions with properly fixed conditions such as in darkness and 0.05Hz frequency. At least five minutes interval was given between the tests and recalibrations were done before each tests. The results of this test were as follows. 1) Vestibular-ocular reflex(VOR) changes according to eye open or closure. In cases of examinees which were given alerting tasks, larger gain was obtained with eyes opened than with eyes closed, and that was statistically significant(p<0.05). In cases of examinees which were not given alerting tasks, larger gain was obtained with eyes opened than with eyes closed, but that was not statistically significant(p>0.05). 2) VOR changes according to alertness. In cases of examinees which opened their eyes, larger gain was obtained with alerting tasks than without alerting tasks, and that was statistically significant(p<0.05). In cases of examinees which closed their eyes, larger gain was obtained with alerting tasks than without alerting tasks, and that was statistically significant(p<0.05). 3) There was no significant changes of asymmetry according to the conditions. Therefore, from above results, we recommend the condition in which examinees open their eyes and be given alerting tasks as one of the optimal condition in sinusoidal harmonic acceleration test.
Acceleration* ; Darkness ; Korea ; Plastics* ; Reflex, Vestibulo-Ocular*

We investigated the vestibulo-ocular reflex which is followed by the change of angular acceleration in sinusoidal harmonic acceleration test. 20 normal volunteers with no evidence of previous otoneurologic disease were tested. The maximal slow phase eye velocity, gain and asymmetry were obtained in five different amplitudes of rotation, 30degrees, 60degrees, 90degrees, 120degrees and 150degrees with properly fixed conditions such as darkness and the frequency of rotation fixed at 0.05Hz. During each test, we asked the examinees to be alert and keep the eyes open. At least 5 minute interval was given between the tests and recalibrations were done before each test. The results of this test were as follows. 1) The maximal slow phase eye velocities were gradually increased according to the increment of the amplitudes of rotation with the statistical significances(p<0.05). 2) The gains were gradually decreased according to the increment of the amplitudes of rotation between the range of 30degrees and 90degrees with the statistical significances(p<0.05). 3) The asymmetries of each amplitude were the highest(13.6%) at 30degrees and the lowest(6.9%) at 120degrees, but there were no statistical significances(p>0.05). Therefore, from the above results, sinusoidal harmonic acceleration test with the frequency fixed at 0.05Hz, gain is higher when the amplitude of rotation is smaller and the pattern of the nystagmus is more evident when the amplitude of rotation is bigger. But The authors conclude that in order to get the results which are statistically significant, the amplitude of rotation should be lower than 90degrees.
Acceleration* ; Darkness ; Healthy Volunteers ; Reflex, Vestibulo-Ocular*

Dark circles refer to visible darkness of the infra-orbital areas. Dark circles are a cosmetic concern for many individuals, although not a medical concern. Moreover, clear definitions and possible causes of dark circles have not been elucidated. This study reviews the possible causes and treatment options for dark circles based on a review of the medical literature and the authors' clinical experience. Potential factors that contribute to dark circles include excessive pigmentation, shadowing due to tear troughs and infra-orbital fat herniation, shadowing due to infraorbital laxity and wrinkles, and thin, translucent skin overlying the orbicularis oculi muscle. Given the different possible causes for dark circles, therapeutic modalities must be individualized for each patient. Because various factors cause dark circles, it is useful to identify the underlying causes in order to select the appropriate treatment.
Darkness ; Humans ; Pigmentation ; Shadowing (Histology) ; Skin ; Tears

The purpose of this study was to evaluate the color changes of the composite resin resulting from xenon lamp exposure in different environments. Composite resin (Z 250 ; shade A1, A2, A3, A3.5, and A4) were applied in a cylindrical metal mold. Seventy five specimens according to environments of exposure were made as follows; Group I: aluminum foiling of the specimens in the air at 37degrees C for 1 day and 7 days. Group II: exposure of xenon lamp to the specimens in the air at 37degrees C for 1 day and 7 days. Group III: exposure of xenon lamp to the specimens in distilled water at 37degrees C for 1 day and 7 days. The color characteristics (L*,a*,b*) of the specimens before and after exposure of xenon lamp were measured by spectrophotometer and the total color differences (DeltaE*) were computed. The results obtained were as follows: 1. In all groups except A1 shade of group III, the DeltaE* values presented below 2.0, and group III showed the highest DeltaE* values followed by group II and group I in a decreasing order(p<0.05). 2. In all shades and groups, the more the exposure time of xenon lamp and the lighter the shade were, the higher the tendency for discoloration (p<0.05). 3. The composite resins which was exposed to xenon lamp in the distilled water was more discolored than those in the air (p<0.05). 4. The major changes of composite resins which were exposed to xenon lamp in the air were an increase in yellowness through a positive shift of the b* value, and those in the distilled water were an increase in darkness and yellowness through a negative shift of the L* value and a positive shift of the b* value.
Aluminum ; Composite Resins* ; Darkness ; Fungi ; Water ; Xenon*

BACKGROUND AND OBJECTIVES: Active head rotation test measures vestibulo-ocular reflex at frequencies of 1 Hz to 8 Hz which correspond to the frequencies of head movements in daily living. However, the normative data of several authors are not in unity, and the usefulness of the test in the evaluation of the peripheral vestibulopathy is yet to be determined. The purpose of this study is to make our own normative data using our own testing condition and facilities and to evaluate the usefulness of the test in the evaluation of the peripheral vestibulopathy. MATERIALS AND METHODS: Active head rotation test was performed in 22 controls and 34 peripheral vestibulopathy patients (24 unilateral, 10 bilateral) using the VORTEQ system in darkness with eyes open (VOR-EO). Gain, phase and symmetry were compared between the control group and the patient groups. RESULTS: The control group showed the gain of 1.0 to 1.1 at frequencies of 1 Hz to 4 Hz. Phase was between 4 to 7 degrees, and symmetry was close to zero. Unilateral vestibulopathy group did not show a significant difference in gain, phase and symmetry from the normal group at the majority of frequencies. Bilateral vestibulopathy group showed a significant gain reduction compared to the normal group and unilateral group (p<0.05). But phase and symmetry were not significantly different. CONCLUSION: The active head rotation test was not useful in evaluating unilateral peripheral vestibulopathy although it was useful in assessing funcitonal deficit of VOR in bilateral vestibulopathy.
Darkness ; Head Movements ; Head* ; Humans ; Reflex, Vestibulo-Ocular

Twenty-five isolates of Fusarium fujikuroi acquired from rice seeds and rice plants evidencing symptoms of Bakanae disease were evaluated to determine their mating types and characterize the formation of their sexual state. The mating types of the isolates were evaluated via multiplex PCR with the diagnostic primers of the mating-type (MAT) region: GFmat1a, GFmat1b, GFmat2c, and GFmat2d. Among the 25 isolates, 11 were identified as MAT-1 (male), and 14 as MAT-2 (female). Four MAT-1 isolates and three MAT-2 isolates were mated and cultured to evaluate the optimal culture conditions for the production of their sexual states. Among four tested media, 10% V8 juice agar proved optimal for the perithecial production of the isolates. The isolates also generated the largest numbers of perithecia when incubated at 23degrees C in alternating cycles of 12 hr fluorescent light and NUV fluorescent light and 12 hr darkness.
Agar ; Darkness ; Fusarium ; Light ; Multiplex Polymerase Chain Reaction ; Seeds

This study was conducted to identify a suitable color of light for development of the fruit body in Hypsizygus marmoreus. To accomplish this, samples were irradiated with blue (475 nm), green (525 nm), yellow (590 nm), or red (660 nm) light emitting diodes (LEDs) to induce the formation of fruiting bodies after mycelia growth. The diameter and thickness of the pileus and length of stipes in samples subjected to blue LED treatment were similar to those of subjected to fluorescent light (control), and the lengths of the stipes were highest in response to treatment with the red LED and darkness. The commercial yields of plants subjected to blue and green LED treatment were similar to those of the control. In conclusion, cultivation of H. marmoreus coupled with exposure to blue LED is useful for inducing high quality fruit bodies as well as higher levels of ergosterol, DPPH radical scavenging activity, total polyphenol content and reducing power.
Agaricales ; Darkness ; Enzyme Multiplied Immunoassay Technique ; Ergosterol ; Fruit ; Light

Periodic alternating nystagmus (PAN) is characterized by horizontal nystagmus that reverses direction periodically. PAN can occur in both congenital and acquired conditions. We report a 58-year old man with peripheral vertigo and hearing impairment showing PAN in darkness.
Darkness ; Hearing Loss ; Meniere Disease ; Nystagmus, Pathologic ; Vertigo