Efectos, agentes y procesos tafonómicos en el área interserrana bonaerense

Este trabajo comprende el estudio, desde una perspectiva tafonómica, del material óseo proveniente de tres sitios arqueológicos, Paso Otero l, Arroyo Seco 2 y Laguna Tres Reyes J, ubicados en el área Interserrana bonaerense. El objetivo es examinar los diferentes agentes involucrados en los procesos tafonómicos que tuvieron lugar en el registro arqueofaunístico del área durante el Pleistoceno final y el Holoceno con el fin de proponer un modelo acerca de su historia tafonómica. Para lograr tal objetivo, se lleva a cabo el análisis anatómico y taxonómico y se enfatiza sobre la identificación de los efectos en los huesos. Los resultados indican que cada uno de los sitios analizados presenta características diferentes asociadas principalmente a la dinámica del ambiente de depositación, a la funcionalidad del sitio y a la intensidad y frecuencia de las ocupaciones humanas. A pesar de las particularidades de cada sitio, se observa que los mismos comparten algunas propiedades, vinculadas principalmente con los agentes responsables de su formación. En este sentido, los seres humanos y los roedores son los agentes tafonómicos biológicos más sobresalientes en todos ellos.The taphonomic study of bone material recovered at three archaeological sites from the lnterserrana area -Paso Otero l, Arroyo Seco 2 and Laguna Tres Reyes 1- is presented. The initial goal is to study the importance of the difierent agents involved in the taphonomic processes that took place in those archaeofaunal assemblages during the Late Pleistocene and Holocene in order to model the taphonomic history ofthose assemblages. In order to do that, an anatomic and taxonomic study is presented, together with an identification of the taphonomic effects observed on the bones. The results indicate that each of the analyzed sites possess different properties which are mainly related with the dynamics of the sedimentary environment, the function of the site and the intensity and frequency of human occupation. Particularities not with standing, there are shared taphonomic properties. Humans and rodents are the main biological taphonomic agents.Sociedad Argentina de Antropologí

Efectos, agentes y procesos tafonómicos en el área interserrana bonaerense

Este trabajo comprende el estudio, desde una perspectiva tafonómica, del material óseo proveniente de tres sitios arqueológicos, Paso Otero l, Arroyo Seco 2 y Laguna Tres Reyes J, ubicados en el área Interserrana bonaerense. El objetivo es examinar los diferentes agentes involucrados en los procesos tafonómicos que tuvieron lugar en el registro arqueofaunístico del área durante el Pleistoceno final y el Holoceno con el fin de proponer un modelo acerca de su historia tafonómica. Para lograr tal objetivo, se lleva a cabo el análisis anatómico y taxonómico y se enfatiza sobre la identificación de los efectos en los huesos. Los resultados indican que cada uno de los sitios analizados presenta características diferentes asociadas principalmente a la dinámica del ambiente de depositación, a la funcionalidad del sitio y a la intensidad y frecuencia de las ocupaciones humanas. A pesar de las particularidades de cada sitio, se observa que los mismos comparten algunas propiedades, vinculadas principalmente con los agentes responsables de su formación. En este sentido, los seres humanos y los roedores son los agentes tafonómicos biológicos más sobresalientes en todos ellos.The taphonomic study of bone material recovered at three archaeological sites from the lnterserrana area -Paso Otero l, Arroyo Seco 2 and Laguna Tres Reyes 1- is presented. The initial goal is to study the importance of the difierent agents involved in the taphonomic processes that took place in those archaeofaunal assemblages during the Late Pleistocene and Holocene in order to model the taphonomic history ofthose assemblages. In order to do that, an anatomic and taxonomic study is presented, together with an identification of the taphonomic effects observed on the bones. The results indicate that each of the analyzed sites possess different properties which are mainly related with the dynamics of the sedimentary environment, the function of the site and the intensity and frequency of human occupation. Particularities not with standing, there are shared taphonomic properties. Humans and rodents are the main biological taphonomic agents.Sociedad Argentina de Antropologí

Estado actual de las investigaciones en el sitio Arroyo Seco 2 (Partido de Tres Arroyos, provincia de Buenos Aires, Argentina)

Fil: Politis, Gustavo Gabriel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Arqueología; ArgentinaFil: Gutiérrez, María Amelia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Arqueología; ArgentinaFil: Scabuzzo, Clara. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Arqueología; Argentin

A Study in a Regional Hospital of a Mid-Sized Spanish City Indicates a Major Increase in Infection/Colonization by Carbapenem-Resistant Bacteria, Coinciding with the COVID-19 Pandemic

Bacterial resistance to antibiotics has proven difficult to control over the past few decades. The large group of multidrug-resistant bacteria includes carbapenemase-producing bacteria (CPB), for which limited therapeutic options and infection control measures are available. Furthermore, carbapenemases associate with high-risk clones that are defined by the sequence type (ST) to which each bacterium belongs. The objectives of this cross-sectional and retrospective study were to describe the CPB population isolated in a third-level hospital in Southern Spain between 2015 and 2020 and to establish the relationship between the ST and the epidemiological situation defined by the hospital. CPB were microbiologically studied in all rectal and pharyngeal swabs and clinical samples received between January 2015 and December 2020, characterizing isolates using MicroScan and mass spectrometry. Carbapenemases were detected by PCR and Sanger sequencing, and STs were assigned by multilocus sequence typing (MLST). Isolates were genetically related by pulsedfield gel electrophoresis using Xbal, Spel, or Apal enzymes. The episodes in which each CPB was isolated were recorded and classified as involved or non-involved in an outbreak. There were 320 episodes with CPB during the study period: 18 with K. pneumoniae, 14 with Klebisella oxytoca, 9 with Citrobacter freundii, 11 with Escherichia coli, 46 with Enterobacter cloacae, 70 with Acinetobacter baumannii, and 52 with Pseudomonas aeruginosa. The carbapenemase groups detected were OXA, VIM, KPC, and NDM with various subgroups. Synchronous relationships were notified between episodes of K. pneumoniae and outbreaks for ST15, ST258, ST307, and ST45, but not for the other CPB. There was a major increase in infections with CPB over the years, most notably during 2020, coinciding with the COVID-19 pandemic. This study highlights the usefulness of gene sequencing techniques to control the spread of these microorganisms, especially in healthcare centers. These techniques offer faster results, and a reduction in their cost may make their real-time application more feasible. The combination of epidemiological data with real-time molecular sequencing techniques can provide a major advance in the transmission control of these CPB and in the management of infected patients. Real-time sequencing is essential to increase precision and thereby control outbreaks and target infection prevention measures in a more effective manner

The arrival of Homo sapiens into the Southern Cone at 14,000 years ago

The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P.) and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.). Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM) in the North America.Facultad de Ciencias Naturales y Muse

Analysis of the lithic assemblages from Paso Otero 4 (Necochea district, Buenos Aires Province). Advances in the knowledge of the technological strategies in the middle basin of the Quequén Grande river during the late Pleistocene-Holocene)

El sitio Paso Otero 4 forma parte de la localidad arqueológica homónima, ubicada en la cuenca media del río Quequén Grande (Partido de Necochea); las ocupaciones humanas fueron datadas en ca. 8900-4600 años AP. El primer objetivo de este trabajo es dar a conocer las principales tendencias de la tecnología lítica, básicamente referidas al aprovisionamiento de rocas, las técnicas de talla, los objetivos de producción y las etapas de las cadenas operativas representadas en los dos niveles arqueológicos que componen el sitio. Sobre la base de esta información se discute su funcionalidad. El segundo objetivo es la comparación de los resultados obtenidos del sitio Paso Otero 4 con los de los sitios Paso Otero 5 (transición Pleistoceno- Holoceno), Paso Otero 3 (Holoceno medio) y Zanjón Seco 2 (Holoceno tardío). A partir de los resultados obtenidos se proponen cambios en las estrategias tecnológicas durante el Pleistoceno final-Holoceno para el curso medio del río Quequén Grande. Estos incluyen, entre otros, una reducción en las áreas de captación de recursos líticos y la incorporación de estrategias de aprovisionamiento de lugares.Paso Otero 4 is located in the middle basin of the Quequén Grande River (Necochea District, Argentina), within the Paso Otero archaeological locality. Human occupations were dated at ca. 8900-4600 years BP. The aim of this paper is to present the main trends of the lithic technology at the site, basically in relation with raw material acquisition, knapping techniques, tool production and the stages of the chaine operatoire represented in the two archaeological levels that compose the site. On the basis of this information the functionality of the site is discussed. Finally, the results presented in this paper are compared with the available lithic information from nearby sites of different chronology: Paso Otero 5 (Pleistocene-Holocene transition), Paso Otero 3 (Middle Holocene) and Zanjón Seco 2 (Late Holocene). Changes in the technological strategies during the Late Pleistocene-Holocene periods in the middle basin of the Quequén Grande River are proposed. The latter includes, among others, a reduction in the catchment areas of lithic resources and a provisioning places strategy.Sociedad Argentina de Antropologí

Analysis of the lithic assemblages from Paso Otero 4 (Necochea district, Buenos Aires Province). Advances in the knowledge of the technological strategies in the middle basin of the Quequén Grande river during the late Pleistocene-Holocene)

El sitio Paso Otero 4 forma parte de la localidad arqueológica homónima, ubicada en la cuenca media del río Quequén Grande (Partido de Necochea); las ocupaciones humanas fueron datadas en ca. 8900-4600 años AP. El primer objetivo de este trabajo es dar a conocer las principales tendencias de la tecnología lítica, básicamente referidas al aprovisionamiento de rocas, las técnicas de talla, los objetivos de producción y las etapas de las cadenas operativas representadas en los dos niveles arqueológicos que componen el sitio. Sobre la base de esta información se discute su funcionalidad. El segundo objetivo es la comparación de los resultados obtenidos del sitio Paso Otero 4 con los de los sitios Paso Otero 5 (transición Pleistoceno- Holoceno), Paso Otero 3 (Holoceno medio) y Zanjón Seco 2 (Holoceno tardío). A partir de los resultados obtenidos se proponen cambios en las estrategias tecnológicas durante el Pleistoceno final-Holoceno para el curso medio del río Quequén Grande. Estos incluyen, entre otros, una reducción en las áreas de captación de recursos líticos y la incorporación de estrategias de aprovisionamiento de lugares.Paso Otero 4 is located in the middle basin of the Quequén Grande River (Necochea District, Argentina), within the Paso Otero archaeological locality. Human occupations were dated at ca. 8900-4600 years BP. The aim of this paper is to present the main trends of the lithic technology at the site, basically in relation with raw material acquisition, knapping techniques, tool production and the stages of the chaine operatoire represented in the two archaeological levels that compose the site. On the basis of this information the functionality of the site is discussed. Finally, the results presented in this paper are compared with the available lithic information from nearby sites of different chronology: Paso Otero 5 (Pleistocene-Holocene transition), Paso Otero 3 (Middle Holocene) and Zanjón Seco 2 (Late Holocene). Changes in the technological strategies during the Late Pleistocene-Holocene periods in the middle basin of the Quequén Grande River are proposed. The latter includes, among others, a reduction in the catchment areas of lithic resources and a provisioning places strategy.Sociedad Argentina de Antropologí

Factors influencing the ground thermal regime in a mid-latitude glacial cirque (Hoyo Empedrado, Cantabrian Mountains, 2006–2020)

.Air and near-surface ground temperatures were measured using dataloggers over 14 years (2006–2020) in 10 locations at 2262 to 2471 m.a.s.l. in a glacial cirque of the Cantabrian Mountains. These sites exhibit relevant differences in terms of substrate, solar radiation, orientation, and geomorphology. Basal temperature of snow (BTS) measurements and electrical resistivity tomography of the talus slope were also performed. The mean annual near-surface ground temperatures ranged from 5.1 °C on the sunny slope to 0.2 °C in the rock glacier furrow, while the mean annual air temperature was 2.5 °C. Snow cover was inferred from near-surface ground temperature (GST) data, estimating between 130 and 275 days per year and 0.5 to 7.1 m snow thickness. Temperature and BTS data show that the lowest part of the talus slope and the rock glacier furrow are the coldest places in this cirque, coinciding with a more persistent and thickest snow cover. The highest temperatures coincide with less snow cover, fine-grained soils, and higher solar radiation. Snow cover has a primary role in controlling GST, as the delayed appearance in autumn or delayed disappearance in spring have a cooling effect, but no correlation with mean annual near-surface ground temperatures exists. Heavy rain-over-snow events have an important influence on the GST. In the talus slope, air circulation during the snow-covered period produces a cooling effect in the lower part, especially during the summer. Significant inter-annual GST differences were observed that exhibited BTS limitations. A slight positive temperature trend was detected but without statistically significance and less prominent than nearby reference official meteorological stations, so topoclimatic conditions reduced the more global positive temperature trend. Probable existence of permafrost in the rock glacier furrow and the lowest part of the talus slope is claimed; however, future work is necessary to confirm this aspect.S

Rasgos morfométricos y morfodinámicos de los glaciares rocosos relictos de la Sierra de Gistredo (Montaña Cantábrica, León)

566 p.La constatación de glaciares rocosos relictos en el Noroeste de las Montañas Cantábricas se inicia al final de la década de los ochenta del siglo pasado con el trabajo de Alonso(1989) en la zona de Degaña-Leitariegos, existiendo nuevas aportaciones a lo largo de los noventa y principios de sigl

The arrival of Homo sapiens into the Southern Cone at 14,000 years ago

The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P.) and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.). Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM) in the North America.Facultad de Ciencias Naturales y Muse