Characterization of Color Production in Xalla´s Palace Complex, Teotihuacan

A multi-analytical approach was used to characterize color remains from Xalla, a Teotihuacan palace complex (project Teotihuacan, Elite and Government. Excavations in Xalla led by Linda R. Manzanilla). Color samples were obtained from polished lithic instruments and pigment ores. Those samples were analyzed combining microscopic and spectroscopic techniques. Our results coincide with previous studies in Teotihuacan, with the chromatic palette displaying a predominance of iron oxides such as hematite, yellow ochre and natural earths, as well as malachite, celadonite and glauconite. We have enlarged the corpus of raw materials with the characterization of jarosite and bone white and mica as aggregate. The identification of raw materials crossed with functional analysis of polished lithic artefacts suggests a production and application process for the pigmenting materials that were divided in four phases, from the crushing of the raw material to the application and finishing of the painted surfaces

Reorganization Energy for Internal Electron Transfer in Multicopper Oxidases.

We have calculated the reorganization energy for the intramolecular electron transfer between the reduced type 1 copper site and the peroxy intermediate of the trinuclear cluster in the multicopper oxidase CueO. The calculations are performed at the combined quantum mechanics and molecular mechanics (QM/MM) level, based on molecular dynamics simulations with tailored potentials for the two copper sites. We obtain a reorganization energy of 91-133 kJ/mol, depending on the theoretical treatment. The two Cu sites contribute by 12 and 22 kJ/mol to this energy, whereas the solvent contribution is 34 kJ/mol. The rest comes from the protein, involving small contributions from many residues. We have also estimated the energy difference between the two electron-transfer states and show that the reduction of the peroxy intermediate is exergonic by 43-87 kJ/mol, depending on the theoretical method. Both the solvent and the protein contribute to this energy difference, especially charged residues close to the two Cu sites. We compare these estimates with energies obtained from QM/MM optimizations and QM calculations in a vacuum and discuss differences between the results obtained at various levels of theory

Exploring four generations' beliefs about career: Is ‘satisfied’ the new ‘successful’?

Purpose – To examine whether four different generations (Silent Generation, Baby Boomers, Generation X and Generation Y) hold different beliefs about career. Career type, career success evaluation and importance attached to organizational security were scrutinized for each generation. Design/methodology/approach – 750 people completed a vignette task, rating the career success of 32 fictitious people. Each vignette contained a different combination of five career features (functional level, salary, number of promotions, promotion speed and satisfaction) at two levels (low and high). Furthermore, several items were added in order to determine each participant’s career type and the extent to which they attached importance to organizational security. Findings – The majority of participants still had rather “traditional” careers, although younger generations seemed to exhibit larger discrepancies between career preferences and actual career situation. Overall, satisfaction appeared to be the overriding criterion used to evaluate other people’s career success. No significant differences were found between generations. With regard to importance attached to organizational security, the Silent Generation and Generation Y scored significantly higher than the other generations. Research limitations/implications – The convenience sampling strategy led to large differences in sample size per generation. Using a vignette design limited the amount and richness of information that could be offered to participants. Perhaps other criteria relevant to real-life career success evaluation were not incorporated in this study. Originality/value of paper – This study raises questions about the validity of career success operationalizations frequently used in research. It is the first study that examines career success evaluation by means of vignettes.status: publishe