Post-mortem wear as indicator of taphonomic processes affecting enamel surfaces of hominin teeth from Laetoli and Olduvai (Tanzania): implications to dietary interpretations

The buccal microwear pattern of premolar and molar teeth has been linked to the composition of the ingested diet in human populations, both extant and fossil. However, numerous enamel surfaces observed for microwear analyses show microscopic damage that can be attributed to post-mortem taphonomic processes, not related to dietary habits. Post-depositional processes may greatly affect enamel surfaces, occasionally hindering dietary reconstructions based on dental microwear patterns. The present study analyses the damage patterns that can be observed on fossil Hominin teeth from the sites of Laetoli and Olduvai (Tanzania) to differentiate between ante-mortem and post-mortem processes. The results obtained show that post-mortem wear can be easily differentiated from ante-mortem abrasion for its distinct effects, mainly consisting of obliteration of enamel features. The frequency of abraded surfaces in the samples studied is considerably high. Despite the great antiquity of the remains studied, patches of well preserved enamel can still be distinguished in a number of teeth. Well preserved enamel surfaces can be discriminated for their polished appearance and the presence of distinct microwear features

Xenotrasplante : el desafío de trasplantar con órganos de otras especies /

Treball presentat a la Facultat de Veterinària de la Universitat Autònoma de Barcelona.Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223

Tooth replication techniques, SEM imaging and microwear analysis in Primates: methodological obstacles

Dental microwear analyses are among the most significant techniques though which a researcher can make dietary and ecological inferences from primate fossil specimens. Hard particles, such as plant phytoliths or silica-base sands, can scratch tooth enamel surfaces during food mastication producing a dietary specific pattern of microwear on the enamel surface. The density, axis length and orientation of microwear features, either striations or pits, are highly informative of dietary habits in both extant and fossil primates. The analysis of tooth enamel surfaces requires the use of scanning electron microscopy (SEM) techniques, because of its high resolution power, including gold-coating of teeth for observation. Problems arise when specimens to be analysed are unique and there is no possibility of a direct observation with an environmental microscope. Negative moulds must then be made and silicone-base components are indicated for high quality replication of enamel surfaces. A positive cast needs to be obtained, and epoxy-base resins are frequently used for their good quality and durability. However, successive silicon and epoxy replications result in the loosing of surface detail and precision. Surface observation errors can also be caused be the SEM technology itself, especially if back-scattered electrons are used instead of secondary electrons for maximizing the topographical information of enamel images. This paper reviews the most commonly used methodological approaches to tooth moulding and casting, comparing SEM micrographs of casts with actual tooth surfaces, and contrasting the reliability of SEM images for dietary interpretation of tooth microwear in both extant and fossil primates

Testing dietary hypotheses of East African hominines using buccal dental microwear data

Abstract There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items

The CBRB regulon: Promoter dissection reveals novel insights into the CbrAB expression network in Pseudomonas putida

CbrAB is a high ranked global regulatory system exclusive of the Pseudomonads that responds to carbon limiting conditions. It has become necessary to define the particular regulon of CbrB and discriminate it from the downstream cascades through other regulatory components. We have performed in vivo binding analysis of CbrB in P. putida and determined that it directly controls the expression of at least 61 genes; 20% involved in regulatory functions, including the previously identified CrcZ and CrcY small regulatory RNAs. The remaining are porines or transporters (20%), metabolic enzymes (16%), activities related to protein translation (5%) and orfs of uncharacterised function (38%). Amongst the later, we have selected the operon PP2810-13 to make an exhaustive analysis of the CbrB binding sequences, together with those of crcZ and crcY. We describe the implication of three independent non-palindromic subsites with a variable spacing in three different targets; CrcZ, CrcY and operon PP2810-13 in the CbrAB activation. CbrB is a quite peculiar σN—depen-dent activator since it is barely dependent on phosphorylation for transcriptional activation. With the depiction of the precise contacts of CbrB with the DNA, the analysis of the multi-merisation status and its dependence on other factors such as RpoN o IHF, we propose a model of transcriptional activation.Ministerio de Economía y Competitividad BIO2014-57545-

Nota metodológica: Alteración del patrón de microestriación dentaria por el efecto wrinkle.

Se describe el efecto wrinkle observado por primera vez sobre moldes dentarios realizados con resinas epoxy y metalizados en oro para su observación mediante microscopía electrónica de barrido (SEM). Con el fin de determinar en qué medida puede afectar al análisis del patrón de microestriación vestibular, se analizan dos muestras dentales de tres especies de Hominoideos, una de ellas incluyendo moldes con presencia de"aguas" relacionadas con el proceso de metalización. Se observa un descenso marcado de la variabilidad del patrón de microestriación dentaria anque las diferencias entre las dos muestras por especie no son estadísticamente significativas. El efecto wrinkle reduce significativamente el porcentaje de clasificación correcta de las especies analizadas a partir del patrón de microestriación y rugosidad dental utilizando un Análisis Discriminante. Se aconseja evitar la inclusión de las muestras afectadas por aguas en los estudios del patrón de microestriación dentaria

Análisis bibliométrico de publicaciones sobre Mentoría en los últimos veinticinco años. A bibliometric analysis of publications in Mentoring in the last twenty-five years.

The aim of this paper is to demonstrate mentorship’s current relevance in the academic, educational and professional fields and its evolution over the last decades. This study is based on the scientific publications on mentorship released in the 1997-2021 period that are indexed in Scopus. For this purpose, the study was carried out through a quantitative methodology and bibliometric techniques. Stages: research strategy outline; indicators and variables selection; result analysis; five-year comparative analysis with other relevant subjects. The results show a consistent increase in the number of publications, particularly in the last five years, during which 47% of the publications were issued; a significant interest in mentorship from Health Sciences (53%), especially in Education; a notable increase in the number of publications on mentorship in comparison to other important subjects during the last five years. The conclusion is that mentorship continues to stay relevant and that there has been an evident interest, particularly from the Health Sciences field regarding Education, which might be due to the noteworthy role of mentors in guarding and encouraging proper practices in Medicine and Research

Múltiples puertas de entrada a la mente de nuestros alumnos : las inteligencias múltiples en el aula de E/LE

The aim of this article is to provide practical guidance to teachers from S/FL, on the application of the theory of multiple intelligences of Howard Gardner (1983) in their didactic and theoretical dimension. To do this, we start from the idea that a didactic and methodological approach from multiple intelligences in the classroom of S/FL can offer alternative ways for teaching Spanish to help students learn and develop the best version of themselves knowing their capabilities and mitigating their limitations in learning a foreign language. It can be also useful as a complement within the communicative approach, as this implementation can serve as a guide for developing the classroom program effectively, contemplating the development of integrated skills, language skills and procedures of student learning. Keywords: S/FL, multiple intelligences, communicative approach, learning, teaching

Sevilian social movements: ecological and feminist concern-actions to build another kind of city?

The focus about sustainability in urban contexts since it became a concern, has been almost exclusively placed in politics coming from institutions and, specifically, in its environmental dimension. However, we believe that the communitarian sphere and the civil society is playing an essential role when it comes to promoting urban politics and opening the close debate about sustainability, to include not only ecological matters, but also social justice and gender equality issues. In fact, we argue that the urban social actors can contribute with their social and environmental practices to define political and ideological proposals to transform the biased and fragmented perspective of sustainability in the city. Therefore, using the case studies methodology, we will approach to the experiences developed in Seville, based on citizen empowerment and mainly aimed to design an urban model that respects the ecosystem and the people. We will also perform a critical analysis of those experiences, to reflect the reach of these movements when it comes to claiming and building a fair and equal city.El foco de atención sobre la sostenibilidad en los contextos urbanos se ha puesto, casi con exclusividad desde los inicios de estas preocupaciones, en las políticas públicas emanadas de las instituciones y, concretamente, en la dimensión ambiental de las mismas. Sin embargo, consideramos que el ámbito comunitario de la sociedad civil está jugando un papel fundamental a la hora de hacer política urbana y de abrir el estrecho debate sobre la sostenibilidad para incluir no sólo cuestiones ecológicas, sino también de justicia social e igualdad de género. De hecho, sostenemos que las actoras y actores sociales urbanos pueden contribuir con sus pra- xis sociales y ambientales a formular propuestas políticas e ideológicas que sirvan para transformar el sesgado y fragmentado enfoque sobre sostenibilidad en la ciudad. Por ello, a través de la metodología del estudio de casos, nos acercaremos a algunas experiencias puestas en marcha en Sevilla que parten del empoderamiento ciudadano y que tienen como objetivo diseñar un modelo urbano respetuoso con el ecosistema y con todas las personas. A partir de las mismas realizaremos un análisis crítico para reflejar los alcances de estos movi- mientos a la hora de reivindicar y construir una ciudad ecológicamente viable, justa y equitativa

New evidence and interpretation of subvertical grooves in eandertal teeth from Cueva de Sidrón (Spain) and Figueira Brava (Portugal)

Interproximal tooth wear is caused by tooth-to-tooth rubbing that results in the formation of flat wear surfaces characterized by an intense pattern of enamel pitting caused by prism-plucking. The rate of wear of such surfaces depends on the forces involved in food processing and chewing. In some instances, the interproximal wear facets, mainly of molar teeth, show a number of subvertical grooves with a nearly vertical direction. These grooves are mostly present in Neanderthal teeth, but have also been described in some African fossil teeth and in European Homo heidelbergensis, as well as in several modern hunter-gatherer populations, such as Australian Aborigines. Subvertical grooves have seldom been attributed to taphonomic processes, although most probably they are caused by natural biomechanical processes during mastication of hard objects included in the diet. They have also been associated to acidic dietary habits given their radial disposition and their inter-digitalisation. The present study analyses the subvertical grooves observed in the Neanderthal dentition of Cueva de Sidrón (Spain). Comparisons are made with the similar interproximal grooves pattern observed in the Neanderthal specimen from Figueira Brava (Portugal) and some remains of H. heidelbergensis from Sima de los Huesos (Spain). Other cases have been described for the Neanderthal sites of Genay and Le Fate (France). The results obtained allow discarding a post-mortem origin of these structures, the most probable cause of the subvertical grooves being natural biomechanical chewing processes combined with some dietary habits indicative of hard plant foods ingestion