Bone-eating Osedax worms lived on Mesozoic marine reptile deadfalls.

We report fossil traces of Osedax, a genus of siboglinid annelids that consume the skeletons of sunken vertebrates on the ocean floor, from early-Late Cretaceous (approx. 100 Myr) plesiosaur and sea turtle bones. Although plesiosaurs went extinct at the end-Cretaceous mass extinction (66 Myr), chelonioids survived the event and diversified, and thus provided sustenance for Osedax in the 20 Myr gap preceding the radiation of cetaceans, their main modern food source. This finding shows that marine reptile carcasses, before whales, played a key role in the evolution and dispersal of Osedax and confirms that its generalist ability of colonizing different vertebrate substrates, like fishes and marine birds, besides whale bones, is an ancestral trait. A Cretaceous age for unequivocal Osedax trace fossils also dates back to the Mesozoic the origin of the entire siboglinid family, which includes chemosynthetic tubeworms living at hydrothermal vents and seeps, contrary to phylogenetic estimations of a Late Mesozoic-Cenozoic origin (approx. 50-100 Myr)

Effect of Stocking Rate of Thai-Esaan Native Beef Cattle under Alternate Grazing Methods on Growth Performance and Botanical Changes in Grass-Legume Mixture Pastureland

This experiment was carried out at the University Farm, Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand during April 2011 to September 2012. The work aimed to study effect of stocking rate of Thai-Esaan native beef cattle carried out under “cut and carry” and alternate grazing methods with respect to beef cattle growth performance and the changes in botanical composition of grass-legume mixture regime of the pastureland. Korat soil series (Oxic paleustults) was used. The experiment was laid in a Completely Randomized Design (CRD) with 3 replications and each replication had 2 heads of Thai-Esaan native beef cattle. The experiment consisted of 4 treatments, i.e. T1 (control, “cut and carry” method) had 0.25 rai/head, T2 had a grazing area of pastureland of 0.25 rai/head, T3 had a grazing area of pastureland of 0.50 rai/head and T4 had a grazing area of pastureland of 0.75 rai/head (1 hectare = 6.25 rai). The results showed that Korat soil series (Oxic Paleustults) is a poor fertility soil with an average pH value of 5.5 and most of the available soil nutrients (NPK) were relatively low. Total dry weights of grass plus legume before grazing were highest for T4 than the rest. This result was also found at the end of the experimental grazing period. Crude protein yields were highest with T3 followed by T4, T2 and least with T1 with mean values of 1,789, 1,740, 1,370 and 951 kg/ha, respectively. Feed intake values were highest with T4 followed by T3, T2 and least with T1 with the mean values of 5.65, 4.95, 3.85 and 3.43 kg/head/day, respectively. The difference was large and highly significant (P < 0.01). Average daily live weight gained was higher for T3 and T4 than T2 and T1 with values of 414, 456, 257 and 190 g/day, respectively. The percentages of total fat in rumen were higher for T3 and T4 than T2 and T1 with values of 0.06, 0.05, 0.02 and 0.02, respectively. The difference was large and statistically significant (P < 0.05). Conjugated linoleic acid values of total fat were highest with T4 followed by T3, T2 and T1 with the values of 1.50, 1.12, 0.17 and 0.11%, respectively. The difference was large and statistically significant. Alternate grazing methods significantly affected dry matter yields, botanical composition changes of the pastureland, and the beef cattle performance and also conjugated linoleic acid in the rumen of the beef cattle. Optimum stocking rate of 0.5 rai/head of T3 was the best recommended treatment for Korat soil series (Oxic Paleustults).Peer reviewedFinal Published versio

The Higgs System in and Beyond the Standard Model

After the discovery of the Higgs boson particle on the 4th of July of 2012 at the Large Hadron Collider, sited at the european CERN laboratory, we are entering in a fascinating period for Particle Physics where both theorists and experimentalists are devoted to fully understand the features of this new particle and the possible consequences for High Energy Physics of the Higgs system both within and beyond the Standard Model of fundamental particle interactions. This paper is a summary of the lectures given at the third IDPASC school (Santiago de Compostela, Feb. 2013, Spain) addressed to PhD students, and contains a short introduction to the main basic aspects of the Higgs boson particle in and beyond the Standard Model.Comment: 62 pages, 31 figures, Lectures of the IDPASC School at Santiago de Compostela, Spain, February 201

A thermodynamic basis for prebiotic amino acid synthesis and the nature of the first genetic code

Of the twenty amino acids used in proteins, ten were formed in Miller's atmospheric discharge experiments. The two other major proposed sources of prebiotic amino acid synthesis include formation in hydrothermal vents and delivery to Earth via meteorites. We combine observational and experimental data of amino acid frequencies formed by these diverse mechanisms and show that, regardless of the source, these ten early amino acids can be ranked in order of decreasing abundance in prebiotic contexts. This order can be predicted by thermodynamics. The relative abundances of the early amino acids were most likely reflected in the composition of the first proteins at the time the genetic code originated. The remaining amino acids were incorporated into proteins after pathways for their biochemical synthesis evolved. This is consistent with theories of the evolution of the genetic code by stepwise addition of new amino acids. These are hints that key aspects of early biochemistry may be universal.Comment: 16 pages, 2 tables, 4 figures. Accepted for publication in Astrobiolog

Effect of cassava chips on quality of silage from fresh forage sorghum plus Cavalcade forage legume hay mixtures

Readers are free to share (to copy, distribute and transmit) and to remix (to adapt) the work under the conditions of Attribution, Noncommercial, and Share Alike (see http://creativecommons.org/licenses/by-nc-sa/3.0/)Two experiments investigated the effects on silage quality of adding cassava chips at a range of levels to a sorghum forage plus Cavalcade legume hay mixture at ensiling at the Experimental Farm, Khon Kaen University, Thailand. Cavalcade hay was 15% of chopped sorghum fresh weight and cassava chips were added at 0, 5, 10 and 15% of chopped sorghum fresh weight. The first experiment utilized sorghum and Cavalcade main crops and the second used the ratoon crop of sorghum and 2nd cut of Cavalcade. Dry matter percentage of ensiled mixtures and silages increased (P<0.05) with an increase in cassava chip levels in both experiments, but CP and NDF concentrations decreased (P<0.05). Dry matter degradability increased (P<0.05) with an increase in cassava chip levels up to 10% in both main and ratoon/2nd cut silages. Digestible energy and metabolizable energy of both silages increased significantly with an increase in cassava chip levels up to 10% for main crop and 15% for ratoon/2nd cut crops. While addition of cassava chips improved digestibility and energy content of silage, it lowered CP concentration. Use of fresh Cavalcade instead of hay should increase the CP levels and should be investigated along with animal feeding studies to test acceptance and animal performance.Peer reviewe

Error threshold in simple landscapes

We consider the quasispecies description of a population evolving in both the "master sequence" landscape (where a single sequence is evolutionarily preferred over all others) and the REM landscape (where the fitness of different sequences is an independent, identically distributed, random variable). We show that, in both cases, the error threshold is analogous to a first order thermodynamical transition, where the overlap between the average genotype and the optimal one drops discontinuously to zero.Comment: 10 pages and 2 figures, Plain LaTe

Iron architecture in Britain and America (1706-1880): with special reference to the development of the portable building

"Ignorance, it has been said, is a prerequisite of the historian. This is particularly true of anyone who attempts to survey, however super- ficially, the achievements of the nineteenth century. The material at his hand is so overwhelming in bulk and so bewildering in texture and colour, that all he can do is pick over the tumbled debris of this vast quarry, and select at random a few stones which, when held up to the light, may reveal something of the nature of the complex mass from which they came. "(H. Casson, An Introduction to Victorian Architecture, 1948).As little recent research had been done on the 'portable building' a large part of my study was concentrated on this subject. It soon became obvious that the work of Andrew Handyside of Derby was of particular interest in this field and I was persuaded to publish a paper on their work separately.I have not, therefore, included this material in the main body of the thesis and have only referred to it where the text demanded.The major departure from a generally chronological account was the decision to single out, for reasons of clarity, the account of the contribution of iron to the development of a new style of architecture.Because many of the buildings examined in the thesis may be unfamiliar, I thought it sensible to include a rather large number of plates. This has had the beneficial effect of being able to reduce the length of descriptions of these buildings and to simplify the technical explanations that were necessary. In addition much of the illustrated material is only available in 19th century books, pamphlets and journals, many of which are scarce and therefore difficult to consult.A precise definition of iron architecture is almost impossible. As it was used in the 19th century it referred to the use of iron in a building as its major structural and constructional material and to the use of the material where it had a.radical influence on the appearance of the building. I have followed this general meaning and therefore have excluded from the study iron balconies, railings, gates, and other examples of ornamental ironwork that were added to buildings. In addition engineering structures, such as bridges, piers, and lighthouses, have not been included unless they had a direct effect on the use of iron in architecture

Afrocentric epistemic systems and higher education curriculum. The Case of a university in Zimbabwe

African Afrocentric epistemic systems have impacted upon the existence and practices of African communities throughout the ages. These epistemic systems have influenced the enactment of how Africans have lived in their communities and how they have sustained and used their resources. However, these epistemic systems encountered an existential problem in the promulgation of Eurocentric epistemic systems which marginalized the significance and centrality of Afrocentric epistemic systems in Zimbabwe’s higher education curriculum. This article concerns itself specifically with the higher education curriculum in Zimbabwe in terms of an Afrocentric perspective and investigates ways in which lecturers’ and students’ perceptions towards Afrocentric epistemic systems can be changed considering the problem of the colonization of the Zimbabwe’s higher education curriculum by Eurocentric epistemic systems. This article, therefore, argues for the incorporation of Afrocentric epistemic systems in bringing about a distinctly Afrocentric perspective in the curriculum, the case of a University in Zimbabwe

The multifaceted nature of weight-related self-stigma: Validation of the two-factor weight bias internalization scale (WBIS-2F)

This is the final version. Available from Frontiers Media via the DOI in this record.Internalized weight stigma (IWS) is generally operationalized as self-devaluation due to weight in higher-weight individuals. The most commonly used measure of IWS, the Weight Bias Internalization Scale (WBIS), was developed from an original pool of 19 items. Item selection was guided by statistical techniques based upon an a priori hypothesized unidimensional factor structure. The resulting 11-item scale mostly assesses appearance-related attitudes, fear of stigma, affect, and desire for change, all of which may be a natural response to societal weight stigma, even in the absence of self-devaluation. Items pertaining to self-blame, stigma awareness, perceived legitimacy of weight stigma, and most items pertaining to self-worth, were excluded from the final scale. It is unclear whether an a priori assumption of multi-dimensionality would have produced different results. Methods: Exploratory and confirmatory factor analysis of the original 19-item questionnaire was conducted in 931 higher-weight individuals. Results: A 13-item two-factor structure was identified. Factor 1 comprised seven items that could be loosely conceived as weight-related distress. Factor 2 comprised six items, all of which pertained to weight-related self-worth. Tested individually, the six items making up the self-devaluation factor were an excellent fit for the data on all fit indices. Conclusion: IWS is a multi-dimensional construct. The two-factor WBIS (WBIS-2F) provides options to explore the relationships between different aspects of IWS and upstream and downstream variables. The Self-Devaluation subscale is suitable for standalone use when weight-related self-devaluation per se is the construct of interest.Economic and Social Research Council (ESRC

Superconductors with two critical temperatures

We propose a simple model for superconductors endowed with two critical temperatures, corresponding to two second-order phase transitions, in the framework of the Ginzburg-Landau mean-field theory. For very large Cooper pair self-interaction, in addition to the standard condensation occurring in the Ginzburg-Landau theory, we find another phase transition at a lower temperature with a maximum difference of 15% between the two critical temperatures.Comment: revtex, 3 pages, one eps figur