The Dark Side of Bright Metal Coatings

The surface quality of light reflective metal films on polymer substrates were experimentally examined and evaluated. The study included light optical hotstage microscopy of in-situ samples and scanning electron microscopy. Conditions for producing aluminum metal films with desirable light reflecting properties are relatively demanding. The film formation is a complex series of events which include nucleation, coalescence and crystal growth. Surface flaws, debris or other imperfections are readily visualized with the aid of the optical or the electron microscope. Although complex methods have been developed for the examination of small surface areas with fine-featured metallic films, there was little incentive to adopt the techniques for large samples. This situation prevailed because the simple microscopic evaluations were sufficient to reveal unacceptable qualities. Hotstage microscopy was decisive in understanding the light reflectivity of the metalized layer and the substrate\u27s influence over the deposited film. Prior to the hot stage examination, only the thin section based knowledge supported the film evaluations. There was always the disturbing possibility that some mechanically or chemically introduced artifacts were contributing to the observed surface irregularities and distortions. The hotstage experiments proved that the observed surface corrugations are the result of complex mechanisms which may depend on several factors. These contributing factors include the combined results or the individual interaction between substrate, base coat, residual stress and temperature. Surface corrugations reproduced with the hotstage yielded valuable informations. In some instances, the experiments, pinpointed the underlying cause and in others it indicated the role of the variables

Matrilines in Neolithic cattle from Orkney, Scotland reveals complex husbandry patterns of ancestry

mtDNA, isotopic and archaeozoological analyses of cattle teeth and bones from the Late Neolithic site of Links of Noltland, Orkney, Scotland revealed these animals followed similar grazing regimes but displayed diverse genetic origins and included one cattle skull that carried an aurochs (wild cattle) genetic haplotype. Morphometric analyses indicate the presence of some cattle larger than published dimensions of Neolithic domestic cattle. Several explanations for these finding are possible but may be the evidence of a complex pattern of domestic cattle introductions into Neolithic Orkney and interbreeding between domestic and wild cattle

Medieval and Ottoman period (14th–17th c.) Archaeology in the Drava River region, Hungary

The paper is a short summary of the main archaeological outcomes of an interdisciplinary project in a section of the Drava river crossing the territory of Somogy county, in Hungary. One of the study areas is the vicinity of Berzence where medieval settlement patterns, land use and economy have been reconstructed on the basis of historical sources and an archaeological field survey. A comprehensive review of architectural history and material culture of the Ottoman Period stronghold in Barcs was the other area under investigation. Research there was based on written sources and the archaeological assemblage recovered from the palisaded fort. Zooarchaeological research at this site revealed some significant culture historical aspects of this stronghold. Underwater archaeological investigations carried out in the Drava river itself and aerial exploration of the study areas also supplied valuable archaeological results

Walking commodities: a multi-isotopic approach (δ13C, δ15N, δ34S, 14C and 87/86Sr) to trace the animal economy of the Viking Age town of Birka

Carbon (δ13C), nitrogen (δ15N), and strontium (87/86Sr) isotope analyses have been applied widely over the past four decades to reconstruct human and animal dietary and mobility patterns. Sulfur (δ34S) has recently shown great promise to further enhance isotope analyses of the geologic and hydrologic contexts in which organic material formed. For this case study we applied this suite of multi-isotopic analyses to a dataset of 45 animal bones and teeth from the urban Viking Age town of Birka located in present-day Sweden. This research falls in line with previous studies as a potential way to bridge the understanding of relationships between centers and hinterlands by tracing socioeconomic networks of subsistence and food provisioning utilizing the animal economy as a proxy. The utilization of δ34S values enables terrestrial, marine and freshwater food niches to be disentangled when δ13C and δ15N values may be overlapping between each of the niches. The incorporation of five 87/86Sr samples further allowed us to carefully interpret the movement of animals across the landscape. We identified cattle potentially originating > 180 km from Birka during the earliest stages of occupation (early 8th century CE), while pigs and ovicaprids were more locally reared, indicating the dimensions of the early market economy in the Viking period was complex and multifaceted

Noether's Symmetry Theorem for Variational and Optimal Control Problems with Time Delay

We extend the DuBois-Reymond necessary optimality condition and Noether's symmetry theorem to the time delay variational setting. Both Lagrangian and Hamiltonian versions of Noether's theorem are proved, covering problems of the calculus of variations and optimal control with delays.Comment: This is a preprint of a paper whose final and definite form will appear in the international journal Numerical Algebra, Control and Optimization (NACO). Paper accepted for publication 15-March-201

Evidence for Concurrent Effects of Exposure to Environmental Cadmium and Lead on Hepatic CYP2A6 Phenotype and Renal Function Biomarkers in Nonsmokers

We examined the interrelationships between phenotype of hepatic cytochrome P450 2A6 (CYP2A6), nephropathy, and exposure to cadmium and lead in a group of 118 healthy Thai men and women who had never smoked. Their urinary Cd excretion ranged from 0.05 to 2.36 μg/g creatinine, whereas their urinary Pb excretion ranged from 0.1 to 12 μg/g creatinine. Average age and Cd burden of women and men did not differ. Women, however, on average showed a 46% higher urinary Pb excretion (p < 0.001) and lower zinc status, suggested by lower average serum Zn and urinary Zn excretion compared with those in men. Cd-linked nephropathy was detected in both men and women. However, Pb-linked nephropathy was seen only in women, possibly because of higher Pb burden coupled with lower protective factors, notably of Zn (p < 0.001), in women compared with men. In men, Pb burden showed a negative association with CYP2A6 activity (adjusted β= −0.29, p = 0.003), whereas Cd burden showed a positive association with CYP2A6 activity (adjusted β= 0.38, p = 0.001), suggesting opposing effects of Cd and Pb on hepatic CYP2A6 phenotype. The weaker correlation between Cd burden CYP2A6 activity in women despite similarity in Cd burden between men and women is consistent with opposing effects of Pb and Cd on hepatic CYP2A6 phenotypic expression. A positive correlation between Cd-linked nephropathy (urinary N-acetyl-β-d-glucosaminidase excretion) and CYP2A6 activity in men (r = 0.39, p = 0.002) and women (r = 0.37, p = 0.001) suggests that Cd induction of hepatic CYP2A6 expression and Cd-linked nephropathy occurred simultaneously

Direct and Inverse Variational Problems on Time Scales: A Survey

We deal with direct and inverse problems of the calculus of variations on arbitrary time scales. Firstly, using the Euler-Lagrange equation and the strengthened Legendre condition, we give a general form for a variational functional to attain a local minimum at a given point of the vector space. Furthermore, we provide a necessary condition for a dynamic integro-differential equation to be an Euler-Lagrange equation (Helmholtz's problem of the calculus of variations on time scales). New and interesting results for the discrete and quantum settings are obtained as particular cases. Finally, we consider very general problems of the calculus of variations given by the composition of a certain scalar function with delta and nabla integrals of a vector valued field.Comment: This is a preprint of a paper whose final and definite form will be published in the Springer Volume 'Modeling, Dynamics, Optimization and Bioeconomics II', Edited by A. A. Pinto and D. Zilberman (Eds.), Springer Proceedings in Mathematics & Statistics. Submitted 03/Sept/2014; Accepted, after a revision, 19/Jan/201

Dogs accompanied humans during the Neolithic expansion into Europe

International audienceNear Eastern Neolithic farmers introduced several species of domestic plants and animals as they dispersed into Europe. Dogs were the only domestic species present in both Europe and the Near East prior to the Neolithic. Here, we assessed whether early Near Eastern dogs possessed a unique mitochondrial lineage that differentiated them from Mesolithic European populations. We then analysed mitochondrial DNA sequences from 99 ancient European and Near Eastern dogs spanning the Upper Palaeolithic to the Bronze Age to assess if incoming farmers brought Near Eastern dogs with them, or instead primarily adopted indigenous European dogs after they arrived. Our results show that European pre-Neolithic dogs all possessed the mitochondrial haplogroup C, and that the Neolithic and Post-Neolithic dogs associated with farmers from Southeastern Europe mainly possessed haplogroup D. Thus, the appearance of haplogroup D most probably resulted from the dissemination of dogs from the Near East into Europe. In Western and Northern Europe, the turnover is incomplete and haplogroup C persists well into the Chalcolithic at least. These results suggest that dogs were an integral component of the Neolithic farming package and a mitochondrial lineage associated with the Near East was introduced into Europe alongside pigs, cows, sheep and goats. It got diluted into the native dog population when reaching the Western and Northern margins of Europe

The Origins of Lactase Persistence in Europe

Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (−13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the −13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on −13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the −13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe