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Signaling by the transcription factor nuclear factor kappa B (NF-κB) involves its release from inhibitor kappa B (IκB) in the cytosol, followed by translocation into the nucleus. NF-κB regulation of IκBα transcription represents a delayed negative feedback loop that drives oscillations in NF-ΚB translocation. Single-cell time-lapse imaging and computational modeling of NF-ΚB (RelA) localization showed asynchronous oscillations following cell stimulation that decreased in frequency with increased IκBα transcription. Transcription of target genes depended on oscillation persistence, involving cycles of RelA phosphorylation and dephosphorylation. The functional consequences of NFκB signaling may thus depend on number, period, and amplitude of oscillations., NF-κB is a family of dimeric transcription factors (usually RelA/p65:p50) that regulates cell division, apoptosis, and inflammation (1). NF-κB dimers are sequestered in the cytoplasm of unstimulated cells by binding [...]

ABSTRACT. Old archaeological radiocarbon dating lore has it that caribou antler and bone give different dating results, and that for some fundamental reason antler is unreliable as a dating material. [...]

A fragment of Cassis rufa shell, in modern times a species of the Indian Ocean, was reliably reported from the deep Mousterian deposits excavated at the beginning of the century [...]

D.E. Nelson, radiocarbon scientist in the group which reported early dates for rock-art at two Australian sites in ANTIQUITY 64 (1990), reports a further study which leads him to withdraw [...]

AGE AND DIETARY INFORMATION obtained from carbon isotopic determinations on ancient bone is often contentious [1, 2] because of difficulties in isolating material uncontaminated by either diagenetic processes or laboratory [...]

The existence of daily rhythms in the regulation of many body processes has been well documented in the last 50 years. In particular, many studies have found repeatable daily rhythms in the regulation of body temperature, activity, and metabolic rate. In turtles, however, some results suggest that some turtle species show patterns of temperature choice, while others results suggest no temperature choice. In this study, we measured the daily patterns of activity, preferred temperature, and metabolic rate of snapping turtle (Chelydra serpentina) juveniles. Activity patterns in the laboratory during their normal housing in plastic containers suggest that activity peaks near the transitions of light and dark phases, with smaller bouts of activity during the light phase. In a temperature gradient, movement patterns again suggest greater activity during the light phase, but no difference in preferred temperature between light and dark phases. Finally, preliminary data analysis suggests no obvious difference in resting metabolic rate between light and dark phases.

New Dates on Northern Yukon Artifacts: Holocene Not Upper Pleistocene THE STUDY OF THE TIME AND CIRCUMSTANCES of the human colonization of the New World has preoccupied archeologists for more [...]

Abstract: This further nitrogen isotopic study of Greenlandic Norse archaeological sites provides new evidence of the affect of past human activity on modern plant δ15N values. Grass samples were taken from a number of spatially defined features at four Norse farms and one site interpreted to be a seasonally occupied herding station (sæter). At the farms, un-naturally high δ15N values were found for plants from each sampled feature, including those from the likely infields and a churchyard. At the sæter no strong isotopic effect was expected and none was found. Comparing the data from the farms we found that the average plant δ15N values were similar for features that were functionally alike. We conclude from these observations, that the unusually high plant δ15N values reflect the strong conservation of the isotopic composition of the nitrogenous materials deposited in the past, and the magnitude of the values reflects the amount of this material admixed in the soil. The results confirm previous exploratory studies of this isotopic effect and further demonstrate its potential value as an archaeological tool. [Copyright &y& Elsevier]

Abstract: In a further empirical study of the impact of past human activities on modern plant δ 15N values, plants were collected in each of two growing seasons from several defined contexts of an inland Norse farm in southwest Greenland. The δ 15N measures of the plants show a clear distinction between areas with definite evidence of past human activity and those without. The data for the plants on this farm''s infield indicates that it was purposely fertilized. The intriguing intra- and inter-variations in the 15N values of plants from several structures are not easily explained, but the differences appear to reflect the different functions of the various farm structures. The findings of this study suggest practical applications for future use of plant δ 15N values in archaeology. [Copyright &y& Elsevier]

Abstract: We have observed circumstances in which the ancient human activities that formed archaeological sites have left a strong imprint on the stable nitrogen isotopic ratio of the plants currently growing there. There is apparent meter-scale spatial variability and the effect can persist for at least several centuries. To our knowledge, this isotopic effect has not previously been reported. Here, we introduce this phenomenon and begin to consider its potential as an analytical tool in archaeological reconstruction. [Copyright &y& Elsevier]