All mammal behaviors and functions exhibit synchronization with environmental rhythms. This is accomplished through an internal mechanism that generates and modulates biological rhythms. The circadian timing system, ...

Four. male Wistar rats were housed in pairs of siblings, on LD 12:12h and 22 degrees C + 2 degrees C. Food and water were provided ad libitum. Behavior was videotaped from the 1st to the 3rd month of life. In each age-bracket ...

The aim of this study was to verify, by means of functional methods, whether the circadian rhythm changes adrenergic response patterns in the epididymal half of the vas deferens isolated from control rats as well as from ...

Leaves of Piper aduncum accumulate the anti-fungal chromenes methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate (2). The enzymatic formation of ...

Respiratory rates of individual workers of Camponotus rufipes Fabricius (Hymenoptera: Formicidae) were measured at 25-degrees-C and LD 12:12 h (lights on 06.00 hours), DL 12:12 h (lights on 18.00 hours), LL (850 lux) and ...

In recent decades, the hectic lifestyle of industrialized societies has wrought its effects on the quality of sleep, and these effects are evidenced by a profusion of sleep-related disorders. Regular exposure to artificial ...

The main objectives of this work were to determine the physiological patterns of progesterone on pregnancy and lactation in ewes, and to verify whether the hormone presents a 24h secretion rhythm. Serum levels of progesterone ...

Photic stimulation during specific day periods may induce Fos oncoprotein expression within the ventrolateral part of the suprachiasmatic nucleus (SCN) in the hypothalamus of rodents. This phenomenon appears to be a major ...