Herring-eating killer whales debilitate herring with underwater tail slaps and likely herd herring into tighter schools using a feeding-specific low-frequency pulsed call ('herding' call). Feeding on herring may be dependent upon daylight, as the whales use their white underside to help herd herring; however, feeding at night has not been investigated. The production of feeding-specific sounds ...

A pilot study is conducted to illustrate the potential of using radiance data collected by the Day/Night Band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polarorbiting Partnership (S-NPP) satellite for particulate matter (PM) air quality monitoring at night. The study focuses on the moonless and cloudless nights in Atlanta, Georgia during AugusteOcto...

The core molecular clockwork in the suprachiasmatic nucleus (SCN) is based on autoregulatory feedback loops of transcriptional activators (CLOCK/NPAS2 and BMAL1) and inhibitors (mPER1-2 and mCRY1-2). To synchronize the phase of the molecular clockwork to the environmental day and night condition, light at dusk and dawn increases mPer expression. However, the signal transduction pathways differ ...

Mostly today, illegal activities occur in the darkness of night. So how does one observe an area looking for lawbreakers at night when no means of visual sight is available? Using spotlights to see what is happening modifies the very behaviour that is being witnessed. Infrared cameras allow surveillance personnel to set back at a safe and unnoticeable distance and record the activity as it occu...

PURPOSE Eyes with distant objects in focus in daylight are thought to become myopic in dim light. This phenomenon, often called "night myopia" has been studied extensively for several decades. However, despite its general acceptance, its magnitude and causes are still controversial. A series of experiments were performed to understand night myopia in greater detail. METHODS We used an adaptiv...

The light-dark cycle is the primary synchronizing factor that keeps the internal circadian pacemaker appropriately aligned with the environmental 24-h day. Although it is known that ocular light exposure can effectively shift the human circadian pacemaker and do so in an intensity-dependent manner, the curve that describes the relationship between light intensity and pacemaker response has not ...

Intensive care units provide specialised care for critically ill patients around the clock. However, intensive care unit patients have disrupted circadian rhythms. Furthermore, disrupted circadian rhythms are associated with worse outcome. As light is the most powerful 're-setter' of circadian rhythm, we measured light intensity on intensive care unit. Light intensity was low compared to daylig...

Circadian phase resetting is sensitive to visual short wavelengths (450-480 nm). Selectively filtering this range of wavelengths may reduce circadian misalignment and sleep impairment during irregular light-dark schedules associated with shiftwork. We examined the effects of filtering short wavelengths (<480 nm) during night shifts on sleep and performance in nine nurses (five females and four ...

OBJECTIVE This study examined whether anesthesia residents (physicians in training) performed clinical duties in the operating room differently during the day versus at night. BACKGROUND Fatigue from sleep deprivation and working through the night is common for physicians, particularly during residency training. METHODS Using a repeated-measures design, we studied 13 pairs of day-night matc...