Sunlight is an important cause of damage to plastics, textiles, paints, and other organic materials. Short wavelength ultraviolet light has long been recognized as being responsible for most of this damage2. Spectroradiometric measurements were made to quantify the wide variations in UV content of sunlight under the following conditions: direct summer sunlight, winter sunlight, sunlight filtere...

BACKGROUND Vitamin D is an important factor in human health. Yet, vitamin D deficiency is very common. We aimed to confirm serum 25-hydroxyvitamin D (25OHD) concentration change after sunlight exposure and to elucidate the relationship between the amount of sunlight exposure and serum 25OHD level change by ambulatory lux meter and sunlight exposure questionnaire. METHODS Twenty healthy young ...

OBJECTIVES Suicide rates have widely been reported to peak in spring and summer. A frequent hypothesis is that increased sunlight exposure alters biological mechanisms. However, few attempts have been made to systematically untangle the putative suicidogenic risk of sunlight exposure from that of seasonality. We examined whether average hours of daily sunlight in a month confer additional risk ...

BACKGROUND A limited number of studies suggest that ambient temperature contributes to suicide; these studies typically focus on a single nation and use temporally and spatially aggregated data. OBJECTIVE We evaluated the association between ambient temperature and suicide in multiple cities in three East Asian countries. METHODS A time-stratified case-crossover method was used to explore t...

Several reports indicate that suicide follows a seasonal pattern with a dominant peak during the month of maximum daylight. The purpose of this study was to evaluate the hypothesis that sunshine exposure may trigger suicidal behavior. We found a remarkably consistent pattern of seasonality with peak incidence around June in the northern hemisphere and December in the southern hemisphere. Moreov...

PURPOSE The aim of this study was to determine whether climate factors correlate with variations in the rate of pediatric intussusception cases presenting to the Children's Hospital in Suzhou, China. MATERIAL AND METHODS The hospital records of 5,994 pediatric cases of intussusception who had presented between Aug 2006 and Dec 2011 were retrospectively analyzed. Demographic data and air enema...

1 The author owes a considerable debt to Morris H. Sunshine who read an earlier draft and made extensive suggestions all of which improved this manuscript.