Religious rituals that are painful or highly stressful are hypothesized to be costly signs of commitment essential for the evolution of complex society. Yet few studies have investigated how such extreme ritual practices were culturally transmitted in past societies. Here, we report the first study to analyze temporal and spatial variation in bloodletting rituals recorded in Classic Maya (ca. 2...

Animals can insure themselves against the risk of starvation associated with unpredictable food availability by storing energy reserves or gathering information about alternative food sources. The former strategy carries costs in terms of mass-dependent predation risk, while the latter trades off against foraging for food; both trade-offs may be influenced by an individual's developmental histo...

Gamete formation requires the sequential action of two extrinsic cues, nitrogen deprivation and blue light. The mutants described here are specifically altered in the light-dependent step. Mutations lrg1, lrg3, and lrg4 overcome this light dependence while mutation lrg2 results in a delayed execution of the light-mediated step. The four mutations are linked. The recessive nature of the lrg1, lr...

because of on-call responsibilities, many medical residents are subjected to chronic partial sleep deprivation, a form of sleep restriction whereby individuals have chronic patterns of insufficient sleep. it is unclear whether deterioration in cognitive processing skills due to chronic partial sleep deprivation among medical residents would influence educational exposure or patient safety.twent...

Brassica alboglabra Bailey plants were first grown under full nutrient solution for 2, 3 and 4 weeks and then were transferred to phosphorus (P)-deprivation solution for 3 weeks (–P3), 2 weeks (–P2) and 1 week (–P1), respectively. The total growth duration was 5 weeks for all plants and the full P plants were grown under complete nutrient solution for 5 weeks. Full P and –P1 plants had similar ...

Background and Aims: It is well-recognized that endogenous opioidergic system plays an important role in pain sensitivity, pain perception, and response to some stressing situations. The present study examined the probable role of endogenous opioidergic system in effects of food deprivation on formalin-induced nociceptive behaviors in male and female rats. Methods: To make short-term food d...

The compensatory growth, proximate composition and amino acid contents changes of young yellow catfish (Pelteobagrus fulvidraco R.) (1.63-1.69 g) had been investigated using a 45-day cyclic feed deprivation and re-feeding experiment. The control group (S0) was fed daily with live tubificid worms (Limnodrilus hoffmeisteri), while the S1/4, S1/2, and S1/1 groups cyclically experienced one-day of ...

The intestinal L cell is the principal source of glucagon-like peptide-1 (GLP-1), a major determinant of insulin release. Because GLP-1 secretion is regulated in a circadian manner in rodents, we investigated whether the activity of the human L cell is also time sensitive. Rhythmic fluctuations in the mRNA levels of canonical clock genes were found in the human NCI-H716 L cell model, which also...