Lipid residues preserved in sheltered bedrock features at Gila Cliff Dwellings National Monument, New Mexico

[Research Article]Bedrock features represent various economic, social, and symbolic aspects of past societies, but have historically received little study, particularly in North America. Fortunately, new techniques for analyzing spatial configurations, use-wear, and organic residues are beginning to unlock more of the interpretive potential of these features. Though preliminary in nature, the present study contributes to this trend by documenting an application of lipid analysis to bedrock features in a dry rockshelter. Results of this initial application indicate that bedrock features in dry rockshelters may provide especially favorable conditions for the preservation and interpretation of ancient organic residues. Abundant lipids, comparable to concentrations present in some pottery sherds, were extracted from a bedrock grinding surface at Gila Cliff Dwellings National Monument and analyzed using gas chromatography-mass spectrometry. Though the lipids were highly oxidized, degradation products indicative of former unsaturated fatty acids were retained. Comparisons to experimentally aged residues, and absence of a known biomarker for maize, indicate that the bulk of the lipids preserved in the milling surface probably derive from processing an oily nut or seed resource, and not from processing maize. Substantially lower amounts of lipids were recovered from a small, blackened cupule. It is hypothesized that some portion of the lipids in the blackened cupule was deposited from condensed smoke of cooking and heating fires in the caves. Potential for the preservation of organic residues in similar sheltered bedrock contexts is discussed, and a practical method for sampling bedrock features in the field is described

Métodos de transducción usados en biosensores: amperometría y fluorescencia

RESUMEN: Los biosensores tienen aplicación en una gran variedad de campos, incluyendo el análisis ambiental, biomedicina, biodefensa, alimentación y agricultura, entre otros. En este tipo de sensores, un material biológico (conocido como biomediador) reacciona con el analito y un sistema de transducción apropiado transforma dicha reacción en una señal eléctrica que puede ser procesada, almacenada o transmitida usando sistemas electrónicos. En este artículo, se describen dos métodos de transducción usados en aplicaciones bio-sensoriales: la amperometria que consiste en la medida del transferimento electrónico (corriente) del biomediador y fluorescencia que es basada en la medida de la luz re-emitida. Se enfatiza en el diseño electrónico (selección de componentes, topologia de los circuitos, problemas comunes y soluciones). Estos diseños han sido utilizados en el desarrollo de instrumentos comerciales para biosensores, caracterizados por bajos costes de producción y portabilidad.ABSTRACT: Biosensor devices have applications in a variety of fields as environmental analysis, biomedical, bio-defense, food and agriculture. On this kind of sensors, a biological material (known as biomediator) reacts with target analytes and an appropriated transduction system converts that reaction to an electrical signal that can be processed, saved and transmitted by using electronic systems. In this article, two transduction methods used for biosensing applications are described: amperometry that is based on the measurement of the electron transfer occurring inside the biomediator and fluorescence, that is based on the measurement of the re-emitted light. Emphasis has been done on the electronics design, including component selection, useful circuit topologies and common problems and solutions. Electronics has been validated for the development of biosensor-based instruments characterized by low production costs and portability

Multiparametric system for biosensing technologies applications based on microarray electrodes

La plataforma biosensoristica aquí descrita ha sido diseñada para el uso de nuevos dispositivos eléctricos y versátiles como el MEA (Matriz de Microelectrodos), el sistema ha sido desarrollado aplicando los principios de la  transducción amperometrica en cada dispositivo especifico. Este documento explica las principales técnicas de medición de esta plataforma y se centra  en los dispositivos MEA de 4 pozos, que permiten el uso de hasta 4 tipos diferentes de biomediadores. El diseño y la construcción también son presentados. El documento se ha estructurado con las siguientes secciones: Hardware, sistema mecánico, software y la aplicación bioquímica. La plataforma descrita puede encontrar aplicación en dos campos diferentes: biomédico para la determinación de posibles anomalías en la sangre humana (por ejemplo: A través de la detección de colesterol, las catecolaminas, el glutamato, y de la bilirrubina en muestras de sangre), y en el campo ambiental para la detección de pesticidas o materiales pesados en agua o alimentos (mediante el uso de biomediadores especiales, tales como el fotosistema II (PSII) o en las membranas tilacoidales extraídas de algas verdes o de plantas). Las señales  procedentes del material están asociadas a los niveles de concentración de cada biomedidador acorde a la linea de caibracion y la sensibilidad de cada material  ABSTRACT The biosensor platform here described has been designed for the use of new, versatile, electric devices, such as MEA (Micro Electrodes Array). The system has been developed applying the principles of the amperometric transduction on each specific device. This paper explains the main techniques of measurement of this platform, and is focused on MEA devices with four wells, which allow the use of up to four different types of biomediators. The Design and construction of the platform are also presented. The paper has been structured with the following sections: hardware, mechanical system, software and biochemical application. The described platform can find application in two different fields: biomedical, for the determination of possible anomalies in the human body (e.g. through the detection of cholesterol, catecholamines, glutamate, and bilirubin in blood samples), and environmental, for the detection of pesticides or heavy metals in water or foods (through the use of special biomediators such as photosystem II (PSII), or thylakoid membranes, extracted from plants or green algae). The signals coming from the biological material are correlated to the concentration levels that detect each biomedidadors according to the calibration line and the sensitivity of the material.

Sex-Ratio, Health, and Social Status: A Biographical Description of Middle and Late Period Bay Area Children

The aim of this paper is to present new information pertaining to the demographic profile of the juvenile burial assemblage (n=39) from a Late Holocene site located on the eastern shore of the San Francisco Bay. CA-ALA-329 is commonly referred to as Ryan Mound and now bears the Muwekma Ohlone name of Mánni Muwékma Kúksú Hóowok Yatiš Túnnešte-tka, which means Place Where the People of the Kúksú (Bighead) Pendants are Buried. This site has been extensively studied and has contributed significantly to our understanding of life on the Bay during the Middle and Late Periods. However, most of the previous studies have focused on adults. The goal of the present study is to identify patterns in the profiles of those who died prematurely, including their sex, their degree of stress experienced based on skeletal indicators of disease/malnutrition, and their social status based on associated grave goods. Results show high incidence of skeletal indicators consistent with nutritional deficiency, disease/infection, and/or metabolic disorder observed in the sample. This suggests that this population was experiencing stress. Individual circumstances, such as age and sex, may also have contributed to poor health because infants have the highest prevalence of cribra orbitalia and periostitis. The distribution of wealth as evidenced by burial goods associated with the sample shows some correlation with age-at-death and the types of artifacts. Distribution of wealth also differs temporally. Inequality seems to have been highest in the Middle Period, while inequality decreased, but overall wealth increased, into the Late Period

Electrochemical and morphological layer-by-layer characterization of electrode interfaces during a label-free impedimetric immunosensor build-up: The case of ochratoxin A

Abstract In this paper, we provide an in-depth electrochemical characterization of a label-free impedimetric immunosensor for rapid detection of ochratoxin A. The sensor was based on a carbodiimide-mediated amide coupling reaction to immobilize a specific ochratoxin A antibody onto 4-mercaptobenzoic acid-modified commercial screen-printed gold electrode. Different variables affecting the performance of the developed sensor were optimized. Cyclic voltammetry and electrochemical impedance spectroscopy were used to analyse modifications of the interfacial properties occurring at each step of the biosensor assembly. The free electrode surface area, the diffusion coefficient, the peak-to-peak separation, the heterogeneous electron transfer constant, and charge transfer resistance have been calculated and compared. The decrease of charge transfer resistance values was linearly proportional to the ochratoxin A concentration in the range of 0.37– 2.86 ng/mL, with a detection limit of 0.19 ng/mL, a limit of quantification of 0.40 ng/mL, very good selectivity, reproducibility, and storage stability in the absence of antifouling agents. Surface morphology and topographic data at each step of the immunosensor assembly were studied by Atomic Force Microscopy, which also provided information on the specific binding of ochratoxin A. Finally, contact angle measurements revealed the hydrophilicity evolution of the surface during sensor assembly enabling OTA binding

New platform of biosensors based on fluorescence detection for enviromental applications

Multilights es un instrumento para la detección de la fluorescencia en aplicaciones bio-sensoriales, el cual permite procesar simultáneamente diferentes tipos de bio-mediadores (como fluoróforos y materiales fotosintéticos). Este artículo describe los diferentes sistemas que conforman el instrumento, como: celdas de medida, acondicionamiento de señales, electrónica digital, gestión de datos, etc. También ilustra las diferentes pruebas realizadas para verificar el funcionamiento del instrumento y sus resultados. Una aplicación real para este instrumento será la detección de contaminantes en el agua (especialmente pesticidas) usando material fotosintético ABSTRACT Multilights is an instrument for fluorescence detection on biosensor applications, It permits working simultaneously with different types of biomediators (that can be fluorophores or photosynthetic). This article describes the different systems that form the instrument, like measurement cells, signal conditioning, digital electronics, data management, etc. Also instrument testing results are shown. A real application for Multilights will be water contamination detection (especially pesticides and herbicides) using photosynthetic materials

Diseño de un instrumento portátil para aplicaciones ambientales por mediciones amperométricas sobre material biológico

El instrumento portátil optimizado para las medidas  de amperometria, en el monitoreo de  materiales bioactivos ha sido diseñado, fabricado y probado. Expresamente ha sido diseñado, para funcionar con una amplia gama de bio-muestras foto-activas. La cámara  de medición del instrumento; destaca dos tipos de fuentes ópticas para detectar la actividad fotosintética de plantas (p. ej. spinacia oleracea) y microorganismos (p. ej. algas y cyanobacteria). En la cámara son inseridos los electrodos serigrafiados para medir la corriente fotogenerada, ademas cuenta con un sistema de flujo para el transporte del electrólito. La transferencia fotosintética de electrones, es activada por dos LEDs (470nm y 660nm de emisión), para permitir varias longitudes de onda de excitación para utilizarlos con diversos materiales biológicos. El objetivo de la aplicacion, es en campos como agroalimentario, farmacéutico y biomédico. Este Artículo describe algunas de las posibles aplicaciones ambientales ABSTRACT A portable instrument performing amperometric measurements for monitoring bioactive materials has been designed, manufactured and tested. It has been specifically designed to operate with a wide range of photoactive biosamples. The sensing chamber in the instrument features two different optical sources to detect the photosynthetical activity of plants (i.e. spinacia oleracea) and microorganisms (i.e. algae and cyanobacteria). The chamber is provided with screen-printed electrodes to measure the photogenerated current and with a fluidic system for the electrolyte transport. Photosynthetic electron transfer is activated by two LEDs (470nm and 660nm emission) in order to enable various excitation wavelengths and match several different biological materials. Target applications belong to the agro-food, pharmaceutical and biomedical fields. This paper describes some possible environmental application

Biosensors: new frontiers for the environmental analysis

Los biosensores son bioherramientas muy prometedoras, útiles para la detección rápida, sencilla, económica y confiable de muchas muestras reales. Por sus características intrínsecas, estos dispositivos pueden tener una aplicación en muchos campos diferentes, pero parecen ser especialmente útil para aquellos que requieren análisis repetidos diariamente realiza, tales como campos de la biomedicina, la agricultura y el medio ambiente. Este artículo revisa los biosensores que parecía útil para el análisis del medio ambiente. En particular, el trabajo se centró en los biosensores basados en la fotosíntesis, es decir, los biosensores, cuyos elementos de biorreconocimiento están representados por células enteras o partes de las células, capaces de realizar fotosíntesis. Una visión general sobre este tipo de biosensores, incluidos los métodos para inmovilizar los biomediadores y detectar los contaminantes, se da aquí, junto con los más recientes ejemplos de su aplicación ABSTRACT  Biosensors are very promising biotools useful for the fast, simple, cheap and reliable screening of many real samples. For their intrinsic features, these devices can find application in many different fields, but appear particularly useful for those requiring repeated analyses daily performed, such as biomedical, agricultural and environmental fields. This article reviews the biosensors which appeared useful for environmental analysis. In particular, the work focused on photosynthesis-based biosensors, i.e. biosensors whose biorecognition elements are represented by whole cells, or parts of cells, able to photosynthesize. An overview on this type of biosensors, included the methods to immobilize the biomediators and detect the pollutants, is given here along with the most recent examples of their application.

A comparison of proteomic, genomic, and osteological methods of archaeological sex estimation

Sex estimation of skeletons is fundamental to many archaeological studies. Currently, three approaches are available to estimate sex–osteology, genomics, or proteomics, but little is known about the relative reliability of these methods in applied settings. We present matching osteological, shotgun-genomic, and proteomic data to estimate the sex of 55 individuals, each with an independent radiocarbon date between 2,440 and 100 cal BP, from two ancestral Ohlone sites in Central California. Sex estimation was possible in 100% of this burial sample using proteomics, in 91% using genomics, and in 51% using osteology. Agreement between the methods was high, however conflicts did occur. Genomic sex estimates were 100% consistent with proteomic and osteological estimates when DNA reads were above 100,000 total sequences. However, more than half the samples had DNA read numbers below this threshold, producing high rates of conflict with osteological and proteomic data where nine out of twenty conditional DNA sex estimates conflicted with proteomics. While the DNA signal decreased by an order of magnitude in the older burial samples, there was no decrease in proteomic signal. We conclude that proteomics provides an important complement to osteological and shotgun-genomic sex estimation

It's getting hot in here – Microcontextual study of a potential pit hearth at the Middle Paleolithic site of El Salt, Spain

By studying combustion structures, which conceal information about anthropogenic activity, we might learn about their makers. This is especially important for remote time periods like the Middle Paleolithic, whose archaeological record comprises numerous combustion structures. The majority of these are simple, flat, open hearths, although a small number of features situated in pit-like depressions have been recorded. Given that hearths built on a flat surface can result in pit-like color alteration of the underlying sediment, accurate identification of pit hearths is a crucial step prior to behavioral interpretation. Here we present a comprehensive study of a possible pit hearth from the Middle Paleolithic site of El Salt, Spain, using a microcontextual approach combining micromorphology, lipid biomarker analysis, archaeomagnetism and zooarchaeology. This pit hearth involves a true depression containing a thick plant ash deposit. It reached very high temperatures, possibly multiple burning events and long combustion times. Morphologically distinct combustion structures in a single archaeological context may indicate different functions and thus a diverse fire technology, pointing to Neanderthal behavioral variability.ERC Consolidator Grant project PALEOCHAR – 648871 https://erc.europa.eu/funding/consolidator-grants, I + D Project HAR2008-06117/HIST, HAR2015-68321-P (MINECO-FEDER/UE), and the Cultural Heritage Department of the Valencia Government and the Archaeological Museum Camil Visedo of Alcoy, under the direction of Professor Bertila Galván of Universidad de La Laguna, Junta de Castilla y León (project BU235P18), the European Fund for Economic and Regional Development (EFRD) and the project PID2019-105796 GB-I00 of the Agencia Estatal de Investigación (AEI/10.13039/501100011033