New insights on commemoration of the dead through mortuary and architectural use of pigments at Neolithic Çatalhöyük, Turkey.

The cultural use of pigments in human societies is associated with ritual activities and the creation of social memory. Neolithic Çatalhöyük (Turkey, 7100-5950 cal BC) provides a unique case study for the exploration of links between pigments in burials, demographic data and colourants in contemporary architectural contexts. This study presents the first combined analysis of funerary and architectural evidence of pigment use in Neolithic Anatolia and discusses the possible social processes underlying the observed statistical patterns. Results reveal that pigments were either applied directly to the deceased or included in the grave as a burial association. The most commonly used pigment was red ochre. Cinnabar was mainly applied to males and blue/green pigment was associated with females. A correlation was found between the number of buried individuals and the number of painted layers in the buildings. Mortuary practices seem to have followed specific selection processes independent of sex and age-at-death of the deceased. This study offers new insights about the social factors involved in pigment use in this community, and contributes to the interpretation of funerary practices in Neolithic Anatolia. Specifically, it suggests that visual expression, ritual performance and symbolic associations were elements of shared long-term socio-cultural practices.

Power law analysis of the signal-averaged electrocardiogram for identification of patients with ventricular tachycardia: effect of bundle branch block.

Signal-averaged ECGs that use time-domain analysis are useful for the identification of patients at risk for ventricular tachycardia (VT). Bundle branch block (BBB) and other conduction defects reduce the value of this approach, but frequency-domain analysis has shown promise in such patients. The purpose of the present study was to examine a new frequency-domain approach to signal-averaged ECGs in patients with and without BBB: power law scaling (PLS). PLS was performed by plotting the power spectrum of the entire signal-averaged ECG on a plot of log power versus log frequency and determining the slope (beta) by least-squares regression. This method was studied in 346 patients. Results of discriminant analysis revealed better sensitivity, specificity, positive predictive value, negative predictive value, and percentage correctly predicted when this method was compared with time-domain indexes. A large proportion of the variance in PLS (19%) was found to be due to findings in patients with VT; whereas the best time-domain index, duration of the filtered QRS signal, explained only 6% of the variance in the group with VT. Mean levels of PLS (+/- standard deviation) were decreased for the group with VT (-3.55 +/- 0.95) as compared with the group without VT (-4.34 +/- 0.59; p < 0.001), suggesting a decrease in the time correlation of the signal. Thus this method of frequency-domain analysis of the signal-averaged ECG was useful in identifying patients with sustained VT despite the presence of significant conduction defects.(ABSTRACT TRUNCATED AT 250 WORDS)

In anterior myocardial infarction, frequency domain is better than time domain analysis of the signal-averaged ECG for identifying patients at risk for sustained ventricular tachycardia.

Low amplitude signals at the end of the QRS in patients with prior myocardial infarction (MI) are related to fragmentation of the electrical impulse in ventricular myocardium and are known to correlate with an increased risk of sustained ventricular tachycardia (VT). We hypothesized that in patients with anterior MI (AMI), earlier activation of the damaged anterior wall would cause an earlier fragmentation of the signal-averaged ECG (SAECG) signal, making conventional time domain analysis of late potentials difficult. We performed SAECG in 213 patients (62 with AMI and 58 with inferior MI [IMI]). Fifty-seven had prior sustained VT; 23 with AMI and 24 with IMI. We examined the standard time domain SAECG parameters including the duration of the filtered QRS (40-250 Hz), the duration of the late QRS < 40 microV, and the root mean square amplitude of the last 40 msec of the QRS. We also examined the power law scaling (PLS) in the frequency domain. Receiver operating characteristic curve analysis of a discriminant function demonstrated significant differences for PLS as compared to time domain indices. An important finding was the significance of MI locus in the time domain indices. PLS did not exhibit this dependence. These data suggest that the usual indices are insufficient for identifying AMI patients at risk of VT. PLS, on the other hand, is valuable regardless of MI location.