OBJECTIVESolar ultraviolet (UV) radiation is an important environmental factor that affects human health. The understanding of diurnal variations of UV radiation at anatomical sites may be helpful in developing ways to protect humans from the harmful effects of UV radiation.

METHODSIn order to characterize the diurnal variations, the UV exposure values were measured at 30 min intervals by using Solar-UV Sensors and a rotating manikin in Shenyang city of China (41 degrees 51'N, 123 degrees 27'E). Measurement data for four representative days (in each of the four seasons respectively) were analyzed.

RESULTSThe diurnal variations in solar UV radiation at the shoulder, the forehead and the chest were similar to those associated with a horizontal control measurement. However, the diurnal variations at the eye and the cheek exhibited bimodal distributions with two peaks in spring, summer and autumn, and a unimodal distribution in winter. The UV exposure peaks at the eye and the cheek were measured at solar elevation angles (SEA) of about 30 degrees and 40 degrees , respectively.

CONCLUSIONThe protection of some anatomical sites such as the eye from high UV exposure should not be focused solely on the periods before and after noon, especially in the places and seasons with high SEA.

No abstract available.
Sleep Disorders, Circadian Rhythm*

No abstract available.
Circadian Rhythm* ; Electroconvulsive Therapy*

The temporary making of heart rhythm emergency in 19 patients at Hai Phong Viet Tiep Hospital from 4/1997 to 11/2002, 10 males and 9 females, average age was 57.10 ± 21.16. Cause: bloc A-V degree III was 63.16%, in which cardiac infarct was 31.58%, sinus node deficiency syndrome was 31.58%. Clinical symptoms: senseless 57.89%, dizzy 37.84%, Adams-Stokes crisis 21.05%, hypotensive and pressure equal zero was 42.10%, mean ventricle frequency was 40.46 ± 11.97 CK/minute, left heart failure 26.31%. 100% machine use have good result. Immediately after machine use: stable pressure, faint sign and Adams-Stokes crisis disappeard. Mortality rate was 0%
Circadian Rhythm ; Arrhythmias, Cardiac ; Emergencies

BACKGROUND AND OBJECTIVES: There are limited data examining triggering activities and circadian distribution at the onset of acute aortic dissection (AAD) in the context of diagnostic and anatomical classification. The aim of this study was to further investigate this relationship between triggering activities and circadian distribution at the onset of AAD according to diagnostic and anatomic classification. SUBJECTS AND METHODS: A total of 166 patients with AAD admitted to Kyungpook National University Hospital between July 2001 and June 2009 were included. To assess the influence of diagnostic and anatomical classification, we categorized the patients into intramural hematoma (IMH) group (n=67)/non-IMH group (n=99) and Stanford type A (AAD-A, n=94)/type B (AAD-B, n=72). To evaluate circadian distribution, the day was divided into four 6-hour periods: night (00-06 hours), morning (06-12 hours), afternoon (12-18 hours), and evening (18-00 hours). RESULTS: Most (72%) AAD episodes were related to physical (53%) and mental activities (19%), with about one-third occurring during the afternoon, and only 12% occurring at night. No differences in triggering activities or circadian distribution were observed among the groups. Waking hours including morning, afternoon, and evening correlated with triggering activities (p=0.003). These relationships were observed for the non-IMH (p=0.008) and AAD-B (p=0.003) cases. The remaining categories had similar relationships, but did not reach statistical significance. CONCLUSION: Our findings suggest differences in the relationship between triggering activities and the circadian distribution of the onset of AAD according to diagnostic and anatomical classification.
Aorta ; Circadian Rhythm ; Hematoma ; Humans

No abstract available.
Circadian Rhythm ; Myocardial Infarction ; Prognosis

Adequate amount and quality of sleep are important for metabolic control in patients with type 2 diabetes. Too short or too long sleep time disrupts glycemic control in both prediabetes and type 2 diabetic patients. Circadian misalignment such as shift work is also associated with an increased risk of developing type 2 diabetes. Clinicians should pay attention to the sleep problems and circadian patterns of patients. However, the pathophysiologic mechanism of the association between sleep and diabetes is likely to be complex and bidirectional. The underlying mechanism remains poorly understood, and further research is warranted.
Circadian Rhythm ; Humans ; Prediabetic State

The purpose of the present study is to explore the relationship of spatial learning ability and specific electrical activities of neural oscillations in the rat. The fast and general avoidance response groups were selected on the basis of the animals' responses to the electric shock in Y type maze, and their local field potentials (LFPs) of hippocampal CA3 area were recorded by wireless telemetry before and after shock avoidance training, respectively. The components of neural oscillations related to spatial identifying and learning ability were analyzed. The results showed that, compared with the general avoidance response group, the fast avoidance response group did not show any differences of LFPs in hippocampal CA3 area before electric shock avoidance trial, but showed significantly increased percentages of 0-10 Hz and 30-40 Hz rhythm in right hippocampal CA3 area after the shock avoidance training (P < 0.01 or P < 0.05). Fast Fourier transform showed that percentage increase of 0-10 Hz band occurred mainly in θ (3-7 Hz) frequency, and 30-40 Hz frequency change was equivalent to the γ1 band. Furthermore, compared with those before training, only the percentages of β, β2 (20-30 Hz) and γ1 rhythm increased (P < 0.01 or P < 0.05) in fast avoidance response rats after training, while the θ rhythm percentage remained unchanged. In contrast, θ rhythm percentage and the large amplitude (intensity: +2.5 - -2.5 db) θ waves in right CA3 area of general avoidance response rats were significantly reduced after training (P < 0.01). These results suggest that the increased percentages of β2 and γ1 rhythm and high-level (unchanged) percentage of θ rhythm in the right hippocampus CA3 area might be related to strong spatial cognition ability of fast avoidance response rats.
Animals ; Avoidance Learning ; Beta Rhythm ; CA3 Region, Hippocampal ; physiology ; Electroshock ; Gamma Rhythm ; Rats ; Spatial Learning ; Theta Rhythm

There are short-term and long-term variations seen in blood pressure. An abnormal pattern in cyclic variations of blood pressure (diurnal or seasonal) correlates well with an increased cardiovascular risk for hypertension, regardless of the resting blood pressure level. Increased blood pressure reactivity to external stimuli is also associated with a higher cardiovascular risk, and may be a significant determinant of cyclic blood pressure variations. A further understanding of the pathophysiological basis of abnormal blood pressure variations is recommended, and the physiological factors should be considered as new therapeutic targets.
Blood Pressure ; Circadian Rhythm ; Hypertension ; Prognosis ; Seasons

While circadian rhythms in fluid intake, urine production, and urine storage have been substantiated in diurnal human and nocturnal rodents, the mechanism(s) underlying it is largely unknown. With the elucidations of molecular clockwork and its functional significance in mammals, new opportunities arise to investigate possible circadian control of voiding function and dysfunction, which undoubtedly needs immediate attentions of researchers in the field.
Attention ; Circadian Rhythm ; Humans ; Mammals ; Rodentia