65 research outputs found
An examination of selected trace elements in modern and ancient samples of triticum spelta
Analyses were made of concentrations of six elements ( the micronutrients copper, iron, manganese and zinc, and the macronutrients calcium and magnesium ) in samples of Triticum spetta and the soil they were grown on to investigate relationships between the two, and the possibility of sourcing material found in the archaeological record. Charred and fresh grains of geographically and geologically diverse locations were broken down in nitric acid using a microwave digestion technique. The resultant solutions were analysed by atomic absorption spectroscopy. Soil extractions using nitric acid and diethylene triamine penta-acetic acid allowed analyses of total and available elements. The results of soil / grain digests were investigated but no consistently significant relationships could be discerned. Growth experiments were performed by growing grain samples from various locations on one soil type to assess which factors were primarily important in elemental uptake. Calcium and magnesium uptake appears strongly influenced by the growing environment, but that of the micronutrients is additionally affected by genetic factors. In order to assess changes in elemental concentration due to burial, diagenetic experiments were carried out using grain from various locations and a series of differing burial periods. It was found that there was a trend for concentrations of the micronutrients and magnesium to decrease, whilst calcium concentrations increased substantially. On completion of work with modem grain, samples from the archaeological record were analysed. Elemental concentrations were found to be very different in ancient material and more significantly related to the burial environment. It appears possible to differentiate between leached, rural and waterlogged / urban sites
Rethinking Measures of Democracy and Welfare State Universalism: Lessons from Subnational Research
Democracy and the welfare state are two of the most extensively studied concepts and themes in the field of comparative politics. Debate about how to best measure the two concepts has failed to contemplate the extent to which political and social rights are uniformly present across distinct regions of the national territory, despite the presence of substantial subnational research that underscores wide variation inside countries. We argue that this omission hampers our understanding of the two phenomena and we propose a new measure of democracy and healthcare unversalism, which we call the Adjusted Measures of Democracy and Welfare Universalism. The new measures integrate territorial inequality into existing national-level indicators, providing a more accurate picture of country performance and opening the door to new, multi-level theory building
The Science Performance of JWST as Characterized in Commissioning
This paper characterizes the actual science performance of the James Webb
Space Telescope (JWST), as determined from the six month commissioning period.
We summarize the performance of the spacecraft, telescope, science instruments,
and ground system, with an emphasis on differences from pre-launch
expectations. Commissioning has made clear that JWST is fully capable of
achieving the discoveries for which it was built. Moreover, almost across the
board, the science performance of JWST is better than expected; in most cases,
JWST will go deeper faster than expected. The telescope and instrument suite
have demonstrated the sensitivity, stability, image quality, and spectral range
that are necessary to transform our understanding of the cosmos through
observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures;
https://iopscience.iop.org/article/10.1088/1538-3873/acb29
La competencia electoral y la descentralización partidista en México
Como en los últimos años ha habido tantos trabajos centrados en el proceso de descentralización fiscal, casi ninguna investigación sobre política mexicana ha analizado el tema de la descentralización partidista. Este artículo sostiene que debido al aumento de la competencia electoral los dirigentes políticos subnacionales han obtenido control sobre importantes recursos políticos, como nominaciones, financiamiento de campañas y puestos futuros. A fin de medir el alcance de estos cambios, se utilizan datos sobre la carrera política de candidatos al Senado por parte del PRI, para medir la descentralización en el que fue uno de los partidos más centralizados del mundo
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