La microscopía como herramienta metodológica en zooarqueología y tafonomía en Chile: casos y perspectivas

The development of microscopy for the archaeological materials analysis since the early ‘50s, has strongly impacted the development of analytical methodologies that allow access to a record, otherwise, inaccessible. However, Latin America has remained relatively outside to the development of such innovations. In the last decade, however, the use of microscopy of different nature and magnification levels, and still has gained a shy impulse among researchers, perhaps coinciding with an increased interest in technology and bone traceology. In this paper we presents a synthesis of the impact of the use of microscopes (and especially at Scanning Electron Microscope) in chilean zooarchaeology and taphonomy from the analysis of specific cases, a critical assessment of their capabilities, technical requirements, costs and weaknesses in the context of zooarchaeological research.La utilización de la microscopía en materiales en arqueológicas a partir de los años 50, ha repercutido fuertemente en el desarrollo de metodologías de análisis que permiten acceder a un registro inaccesible por otros medios. No obstante, Latinoamérica había permanecido relativamente ajena al desarrollo de dichas innovaciones. En la última década, sin embargo, la utilización de microscopía de diferentes aumentos y naturalezas ha ido cobrando un tímido impulso entre los investigadores, tal vez en coincidencia con un aumento en el interés por la tecnología y traceología ósea. En el presente trabajo se elabora una síntesis del impacto del uso de microscopía (y especialmente la Microscopía Electrónica de Barrido) en la zooarqueología y tafonomía chilena a partir del análisis de casos específicos, un balance crítico de sus posibilidades, requerimientos técnicos, costos y debilidades en el marco de la investigación zooarqueológica

Tafonomía de mamíferos en la puna de Atacama: el sitio Tulan-54, Norte de Chile

El present treball busca comprendre la manera en la qual es van formar els dipòsits que colmataron les estructures del lloc Tulan-54, a la Puna d'Atacama, Nord de Xile. El lloc correspon a un conjunt arquitectònic en el qual destaca una estructura central, els trets van ser completament coberts cap als ca. 2000 ap., Moment en el qual s'abandona el seu ús. Diverses han estat les interpretacions que s'han fet sobre el paper que aquest va assetjar va jugar en la prehistòria atacameña durant el primer mil·lenni abans de l'era cristiana, però, durant l'última dècada, les investigacions desenvolupades en l'àrea han confirmat el caràcter eminentment cerimonial del lloc, destacant els seus atributs com a centre cerimonial de rellevància en un escenari social andí que assistia al procés d'implantació i estabilització del trànsit de béns a gran escala en el marc de xarxes d'intercanvi possibilitades pel sorgiment de la Llama com a animal de càrrega. El lloc, va ser sistemàticament cobert amb pisos de deixalles entre els quals destaquen les restes òssies. Aquestes deixalles, van acabar per colmatar la totalitat de les estructures i que van portar a l'abandonament del lloc al voltant del ca. 2380 ap; i una de les preguntes clau que s'han plantejat sobre el lloc, ha estat l'origen de les restes que colmataron les estructures i la naturalesa del descarti que va produir aquests farcits. Aquesta tesi busca aportar des de la zooarqueologia i la tafonomia a la resposta a aquesta pregunta, per tal de comprendre de millor manera el paper que va jugar el lloc Tulan-54 en la prehistòria andina i les característiques de l'ocupació formativa en els Andes centre sudEl presente trabajo busca comprender la manera en la cual se formaron los depósitos que colmataron las estructuras del sitio Tulan-54, en la Puna de Atacama, Norte de Chile. El sitio corresponde a un conjunto arquitectónico en el que destaca una estructura central, cuyos rasgos fueron completamente cubiertos hacia los ca. 2000 ap., momento en el que se abandona su uso. Diversas han sido las interpretaciones que se han hecho acerca del papel que este sitió jugó en la prehistoria atacameña durante el primer milenio antes de la era cristiana, sin embargo, durante la última década, las investigaciones desarrolladas en el área han confirmado el carácter eminentemente ceremonial del sitio, destacando sus atributos como centro ceremonial de relevancia en un escenario social andino que asistía al proceso de implantación y estabilización del tráfico de bienes a gran escala en el marco de redes de intercambio posibilitadas por el surgimiento de la llama como animal de carga . El sitio, fue sistemáticamente cubierto con pisos de desechos entre los que destacan los restos óseos. Estos desechos, acabaron por colmatar la totalidad de las estructuras y que llevaron al abandono del sitio alrededor del ca. 2380 ap; y una de las preguntas clave que se han planteado acerca del sitio, ha sido el origen de los restos que colmataron las estructuras y la naturaleza del descarte que produjo dichos rellenos. Esta tesis busca aportar desde la zooarqueología y la tafonomía a la respuesta a dicha pregunta, a fin de comprender de mejor manera el rol que jugó el sitio Tulan-54 en la prehistoria andina y las características de la ocupación formativa en los andes centro sur.This work, seeks to understand the way in which the deposits that filled the structures of the Tulan-54 site, in the Puna of Atacama, northern Chile, were formed. The site corresponds to an architectural compound in which a central structure stands out, whose features were completely covered towards the ca. 2000 ap., when it was abandoned. Various interpretations have been made of the role that this site played in Atacama’s prehistory during the first millennium before the Christian era, however, during the last decade, the research developed in the area have confirmed the eminently ceremonial character of the site, highlighting its attributes as a ceremonial center of relevance in an Andean social scene that assisted to the process of implementation and stabilization of large-scale goods traffic within the framework of exchange networks made possible by the emergence of the llama as a cargo animal. The site was systematically covered with debris floors among which the bone assamblages stand out. These wastes eventually filled up all of the structures and led to the abandonment of the site around ca. 2380 ap; and one of the key questions that have been raised about the site, has been the origin of the remains that filled the structures and the nature of the disposal that produced said landfills. This thesis seeks to contribute from zooarchaeology and taphonomy to the answer to this question, in order to better understand the role played by the Tulan-54 site in Andean prehistory and the characteristics of the Formative occupation in the south central Ande

Optical sum rule in metals with a strong interaction

The restricted optical sum rule and its dependence on the temperature, a superconducting gap and the cutoff energy have been investigated. As known this sum rule depends on the cutoff energy and the relaxation rate even for a homogeneous electron gas interacting with impurities or phonons. It is shown here that additional dependence of the spectral weight on a superconducting gap is very small in this model and this effect disappears totally when the relaxation rate is equal zero. The model metal with a single band is considered in details. It is well known that for this model there is the dependence of the sum rule on the temperature and the energy gap even in the case when the relaxation is absent. This dependence exists due to the smearing of the electron distribution function and it is expressed in the terms of Sommerfeld expansion. Here it is shown that these effects are considerably smaller than that of related with the relaxation rate if the band width is larger than the average phonon frequency. It is shown also that the experimental data about the temperature dependence of the spectral weight for the high- materials can be successfully explained in the framework approach based on the temperature dependence of the relaxation rateComment: 13 pages, 7 figures, the talk given on Internatinal coference on theoretical physics, april 11-16,2005, Mosco

Temperature dependence of the spectral weight in p- and n-type cuprates: a study of normal state partial gaps and electronic kinetic energy

The optical conductivity of CuO2 (copper-oxygen) planes in p- and n-type cuprates thin films at various doping levels is deduced from highly accurate reflectivity data. The temperature dependence of the real part sigma1(omega) of this optical conductivity and the corresponding spectral weight allow to track the opening of a partial gap in the normal state of n-type Pr{2-x}Ce(x)CuO4 (PCCO), but not of p-type Bi2Sr2CaCu2O(8+delta} (BSCCO) cuprates. This is a clear difference between these two families of cuprates, which we briefly discuss. In BSCCO, the change of the electronic kinetic energy Ekin - deduced from the spectral weight- at the superconducting transition is found to cross over from a conventional BCS behavior (increase of Ekin below Tc to an unconventional behavior (decrease of Ekin below Tc) as the free carrier density decreases. This behavior appears to be linked to the energy scale over which spectral weight is lost and goes into the superfluid condensate, hence may be related to Mott physics

Intoxicación por metanol con hemorragia e isquemia de los ganglios basales: reporte de dos casos

Se presentan los casos de dos pacientes con historia de alcoholismo crónico que se intoxicaron con metanol y que presentaron ceguera, acidosis metabólica severa, insuficiencia renal aguda y hemorragia en los ganglios basales en un caso de isquemia en el otro

Sequencing and Analysis of the Myostatin Gene (GDF-8) in Bubalus bubalis Young Animals to Determine the Existence of Possible Mutations Expressed in Double Musculature Phenotype

Since the 19th century, the presentation of bovines with disproportionate muscle development have been associated with mutations that inhibit the action of the myostatin gene, it is referred to as double muscle mutation, which is common in some European Bos taurus breeds but it is not reported in buffaloes Bubalus bubalis. This study aims to evaluate if the phenotype observed in 6 young buffaloes with disproportionate muscle development has the same myostatin mutation reported in cattle. DNA was obtained from the blood of the animals of the Murrah breed. First, second and third exon was amplified end point PCR; the fragments were sequenced using capillary electrophoresis. Holstein cattle (Bos taurus) was used As control for normal phenotype. The results obtained from the comparison of the sequence of the myostatin gene show that the observed double-muscled phenotype did not show differences from normal controls. Interspecific variation was demonstrated by comparing exons two and three of the gene, finding 12 variations between the Bos taurus and Bubalus bubalis species in the evaluated fragments. It is necessary to study physiology, and the animals to explain the phenotype observed in buffaloes

Optical Sum Rule anomalies in the High-Tc Cuprates

We provide a brief summary of the observed sum rule anomalies in the high-T$_c$ cuprate materials. A recent issue has been the impact of a non-infinite frequency cutoff in the experiment. In the normal state, the observed anomalously high temperature dependence can be explained as a `cutoff effect'. The anomalous rise in the optical spectral weight below the superconducting transition, however, remains as a solid experimental observation, even with the use of a cutoff frequency.Comment: 4 pages, 2 figures, very brief review of optical sum rule anomal