No / The aim of this article is to discuss radiocarbon dating offsets due to freshwater and marine reservoir effects (FRE and MRE, respectively) in the southeastern Baltic. Thirty-six C-14 dates from Lithuanian coastal and inland Subneolithic, Neolithic, and Bronze Age sites as well as two Mesolithic-Neolithic cemeteries are presented here. Accelerator mass spectrometry (AMS) dates, sometimes paired or tripled, have been obtained on samples of various origin, foodcrusts, or visible charred deposits adhering to the surfaces of ceramic vessel walls were also dated and investigated for stable isotope signals. The results argue for a significant freshwater component in the food processed in ceramic vessels during the Subneolithic and Neolithic. Paired dating of ungulate and human bones at the Spiginas and Donkalnis cemeteries (6300-1900 cal BC) does not suggest an FRE, although stable isotope data on human bone collagen strongly suggest a large input of freshwater food in the diet. An FRE in the order of 320-510 yr was estimated for the Sventoji paleolagoon around 3000 cal BC. At the same time, the FRE of the Curonian Lagoon could be larger as implied by large apparent 14C ages of modern pike-perch (981 +/- 30 BP) and bream (738 +/- 30 BP) bones as well as "foodcrust" offsets (650-530 yr) at Nida (3500-2500 cal BC). An MRE of 190 +/- 43 yr was estimated for the southeastern coast of the Littorina Sea according to offsets between dates of seal bones and terrestrial samples at Nida and Sventoji. Any FRE at Lake Kretuonas remains uncertain due to the limited work to date.

Carbon-14, a radioactive nuclide, is used in many industrial applications. Due to its wide range of uses in industry, many workers are at risk of accidental internal exposure to 14C. Being a low energy beta emitter, 14C is not a significant external radiation hazard, but the internal consequences posed by 14C are important, especially because of its long half life of 5730 years. The current biokinetic model recommended by the International Commission on Radiological Protection (ICRP) is a conservative estimate of how radiocarbon is treated by the human body. The ICRP generic radiocarbon model consists of a single compartment representing the entire human body. This compartment has a biological half life of 40 days yielding an effective dose coefficient of 5.8×10-10 Sv Bq-1. This overestimates the dose of all radiocarbon compounds that have been studied. An improved model has been developed that includes and alimentary tract, a urinary bladder, CO2 model, and an "Other" compartment used to model systemic tissues. The model can be adapted to replicate any excretion curve and excretion pattern. In addition, the effective dose coefficient produced by the updated model is near the mean effective dose coefficient of carbon compounds that have been considered in this research. The major areas of improvement are: more anatomically significant, a less conservative dose coefficient, and the ability to manipulate the model for known excretion data. Due to the wide variety of carbon compounds, it is suggested that specific biokinetic models be implemented for known radiocarbon substances. If the source of radiocarbon is dietary, then the physiologically based model proposed by Whillans that splits all ingested radiocarbon compounds into carbohydrates, fats, and proteins should be used.

<p> The c^13 isotope effect in acid and alkaline hydrolysis of both ethyl and tertiary butyl benzoate-carboxyl-c^14 have been measured. Significant isotope effects were found in all the hydrolyses except acid hydrolysis of the tertiary butyl oster. These results are additional evidence for the suggestion of Choen and Schneider that alkyl oxygen rather than normal acyl oxygen bond cleavage occurs when tertiary butyl benzoate is hydrolyzed in acid solution. No appreciable c^13 isotope effect was found to occur in thermal, aqueous, or acid-catalysed decarboxylation of anthranilic acid. From this observation and other experimental evidence, it is concluded that anthranilic acid decarboxylates by a bimolecular process in which the attack of the hydrogen ion is rate controlling. It is further suggested that the hydrogen ion attack is on the zwitterion at the c carbon position. Both the c^13 and the c^14 isotope effect in the decarboxylation of mesitoic acid were measured using a mass spectrometer. The c^14 isotope effect was found to be two and one half times the magnitude of the c^13 isotope effect instead of twice as present theory predicts. </p> / Thesis / Doctor of Philosophy (PhD)

Thesis advisor: Jeremy D. Shakun / Glaciers in the tropics have undergone significant retreat in the past several decades, but the magnitude of this retreat in the long-term context of the Holocene has mostly been qualitatively assessed. This study produces a quantitative reconstruction of Holocene glacier extent relative to today from the Quelccaya Ice Cap, Peru, and the Rwenzori Mountains of east Africa. I use measurements of in situ 14C and 10Be from bedrock that was recently exposed by glacier retreat to constrain possible bedrock exposure and erosion histories at each site. The results are strikingly similar in both areas, and suggest that ice was generally smaller than today during the first half of the Holocene and larger than today for most, if not all, of the last several millennia. These findings give evidence toward a coherent Holocene expansion of glaciers across the tropics, and suggest that recent retreat is unusual in a multi-millennial context. / Thesis (MS) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.

The study of the characteristics of the Late Archaic Period societies on the North-Central Coast probably is one of the most important areas of archaeological research in the last ten years. This paper evaluates the quality of the current archaeological data. A review of the reported information reveals a need to establish a more precise characterization of the architectural designs and construction processes that shaped the conspicuous public buildings of this period. Also revealed is the need to refine the occupational sequences of the Late Archaic architectural complexes of the North-Central Coast, which is necessary for a better understanding of the processual characteristics of their cultural development. As a beginning point, data recovered from excavations in the site of Cerro Lampay, a small architectural compound of the Fortaleza Valley, are studied. Information from Cerro Lampay is compared with published data from other sites, including Áspero, Chupacigarro, Caral, Caballete, and Porvenir. / La naturaleza de las sociedades del Periodo Arcaico Tardío en la costa norcentral ha sido, probablemente, uno de los temas más recurrentes en los últimos 10 años. Para contribuir a esta discusión, se hace necesaria una evaluación de la calidad de la base empírica existente hasta el día de hoy en el registro arqueológico. Una revisión de los datos documentados revela la necesidad de establecer con mayor precisión las características del diseño arquitectónico y el proceso constructivo de los conspicuos edificios públicos de este periodo. Además, muestra que es necesario el afinamiento de las secuencias ocupacionales de los distintos complejos arquitectónicos del Periodo Arcaico Tardío en la costa norcentral como requisito para entender las características procesales del desarrollo cultural que allí se dio. Esta revisión parte de los datos recuperados en las excavaciones en Cerro Lampay, un pequeño conjunto arquitectónico del valle de Fortaleza. Esta información es comparada con la de otros sitios, como Áspero, Chupacigarro, Caral, Caballete y Porvenir.

This thesis addresses radiocarbon (C-14) dating of bioarcheological finds from Sandby borg, an iron-age ring fort on the east coast of the Baltic Sea island of Öland, Sweden. Archaeological evidence suggests that Sandby borg was used during the European migration period and that its main period of usage was terminated by an isolated incidence of inter-personal violence where the inhabitants were killed or abducted. Radiocarbon dating of individual archaeological finds from this period becomes imprecise due to fluctuations of C-14 ratios in the atmosphere during the period 420-530 AD. In the work presented here, Bayesian modelling, whereby multiple finds as well as chronological information from typology and stratigraphy are combined into a statistical model is deployed, together with an estimate of the percentage of maritime products in the diet of individuals subjected to C-14 dating. The outcome of this analysis suggests that the usage ranges from 410-537 AD (95.4% probability) and that the lethal attack took place between the years 532 and 558 AD (95.4% probability). This latter dating interval is about 40-60 years later than what has been suggested from previous studies. The reliability of the modified chronology and its consequences for our understanding of the Sandby borg site is discussed, and some future directions of research are proposed.

This work deals with monitoring of the radiocarbon in the gaseous effluents from the Temelín nuclear power plant and its distribution in the environment. The reader should gain a comprehensive image about level of radiocarbon monitoring in ventilation systems in the Temelín nuclear power plant and in the surrounding environment. The work is divided into several parts. Some basic information of physics, chemistry and radiobiology relating to radiocarbon are given in the first part. The origin of radiocarbon in VVER reactor, its pathway to gaseous releases and then to carbon cycle in the environment are described there too. This introductory part continues with description of monitoring methods used in ventilation systems of the Temelín nuclear power plant and in the surrounding environment. Summary of Czech Republic legislation related to radiation protection is stated. The aim of the work and hypothesis are set in the second part. In the third part there are methods used to fulfil the aim of the work. The results in the form of tables and graphs are in the fourth part. In the following part there is a discussion of summarized data and results. Developed findings are summarized in the last part of this work.

O estudo de um testemunho coletado às margens de uma lagoa situada em meio a vegetação de Mata Atlântica no Parque Estadual Turístico do Alto Ribeira, sul do estado de São Paulo, permitiu a reconstituição da história da vegetação local ao longo dos últimos 2500 anos. Para isso, foram realizadas análises elementares, isotópicas e palinológicas. Também a partir de material retirado deste testemunho procedeu-se a comparação entre dois protocolos de tratamento químico para análises palinológicas do Quaternário. Os protocolos utilizados seguiram as metodologias propostas por Faegri e Iversen, 1989 (Protocolo 2) e por Colinvaux et al., 1999 (Protocolo 1). Foi desenvolvido um método de comparação que envolveu a quantidade de palinomorfos e a quantidade de matéria orgânica amorfa encontrados em 450 pontos escolhidos aleatoriamente em lâminas de ambos os protocolos e também foram levados em consideração o tempo, a praticidade de aplicação em rotina laboratorial, os custos e as quantidades e tipos de resíduos para cada protocolo. Cinco amostras de sedimento foram utilizadas para comparação e o Protocolo 1 apresentou em média 10% menos matéria orgânica amorfa e quase três vezes mais palinomorfos que o Protocolo 2. Os resultados das análises isotópicas e da palinologia mostraram que a vegetação da área em estudo teve uma fisionomia florestal pelo menos desde os últimos 2550 anos. Os valores de \'delta\'13C, em torno de - 29%o, indicaram a presença de plantas C3 em todo o período estudado e registraram um enriquecimento isotópico (-24,9%o) entre aproximadamente 1650 e 1480 anos AP. A análise palinológica apontou para a ocorrência de um clima mais frio que o atual entre 2550 anos AP e 2000 anos AP, com aumento na freqüência de Araucaria e diminuição de Arecaceae. Também foi detectada a ocorrência de um período de clima mais quente e mais úmido entre aproximadamente 1000 anos AP e 680 anos AP, com desaparecimento de Araucaria e aumento de Arecaceae, Weinmannia e de pteridófitas. A maior umidade deste período também é apontada pelos valores de C/N que indicam aumento de influência terrestre no sedimento e pelo aumento de Botryococcus. Em todas as camadas foram encontradas partículas carbonizadas, indicando períodos de ocorrência de paleoincêndios e de abertura florestal provavelmente associados à presença humana na região / One sediment core collected at the margins of a lake surrounded by Atlantic rainforest vegetation at Parque Estadual do Alto Ribeira (PETAR), southern São Paulo state (Brazil), was analyzed, in order to reconstruct the history of the local vegetation over the last 2500 years. Elemental (Total Organic Carbon TOC and Total Organic Nitrogen), isotopic (C and N), pollen analysis and radiocarbon dating were integrated on this work. Also was made a comparison of two protocols for Quaternary pollen chemical treatment. The tested protocols were proposed by Faegri and Iversen, 1989 (Protocol 2) and by Colinvaux et al., 1999 (Protocol 1). The comparison methods developed in this study checked the protocols performance on the quantity of palinomorphs and of organic matter found in 450 random areas of microscope slides of each protocol. The time consuming, laboratory routine, costs and residue production by the protocols were considered for comparison. Five samples were used for comparison and the Protocol 1 showed an average of 10% less organic matter and more palinomorphs than Protocol 2. According to the isotopic and pollen results, the study area vegetation maintained as a forest for the last 2500 years BP. \'delta\'13C values of -29%o indicated the presence of C3 plants during all the sediment study and a isotopic enrichment (- 24,9%o) was observed between 1650 and 1480 yrs BP. Pollen analysis suggested the occurrence of colder climatic conditions between 2550 and 2000 yrs BP and a warmer and humid period was suggested between 1000 and 680 yrs BP. Charcoal particles were found since 2550 yrs BP indicating paleofire probably associated to the human activities

O estudo de um testemunho coletado às margens de uma lagoa situada em meio a vegetação de Mata Atlântica no Parque Estadual Turístico do Alto Ribeira, sul do estado de São Paulo, permitiu a reconstituição da história da vegetação local ao longo dos últimos 2500 anos. Para isso, foram realizadas análises elementares, isotópicas e palinológicas. Também a partir de material retirado deste testemunho procedeu-se a comparação entre dois protocolos de tratamento químico para análises palinológicas do Quaternário. Os protocolos utilizados seguiram as metodologias propostas por Faegri e Iversen, 1989 (Protocolo 2) e por Colinvaux et al., 1999 (Protocolo 1). Foi desenvolvido um método de comparação que envolveu a quantidade de palinomorfos e a quantidade de matéria orgânica amorfa encontrados em 450 pontos escolhidos aleatoriamente em lâminas de ambos os protocolos e também foram levados em consideração o tempo, a praticidade de aplicação em rotina laboratorial, os custos e as quantidades e tipos de resíduos para cada protocolo. Cinco amostras de sedimento foram utilizadas para comparação e o Protocolo 1 apresentou em média 10% menos matéria orgânica amorfa e quase três vezes mais palinomorfos que o Protocolo 2. Os resultados das análises isotópicas e da palinologia mostraram que a vegetação da área em estudo teve uma fisionomia florestal pelo menos desde os últimos 2550 anos. Os valores de \'delta\'13C, em torno de - 29%o, indicaram a presença de plantas C3 em todo o período estudado e registraram um enriquecimento isotópico (-24,9%o) entre aproximadamente 1650 e 1480 anos AP. A análise palinológica apontou para a ocorrência de um clima mais frio que o atual entre 2550 anos AP e 2000 anos AP, com aumento na freqüência de Araucaria e diminuição de Arecaceae. Também foi detectada a ocorrência de um período de clima mais quente e mais úmido entre aproximadamente 1000 anos AP e 680 anos AP, com desaparecimento de Araucaria e aumento de Arecaceae, Weinmannia e de pteridófitas. A maior umidade deste período também é apontada pelos valores de C/N que indicam aumento de influência terrestre no sedimento e pelo aumento de Botryococcus. Em todas as camadas foram encontradas partículas carbonizadas, indicando períodos de ocorrência de paleoincêndios e de abertura florestal provavelmente associados à presença humana na região / One sediment core collected at the margins of a lake surrounded by Atlantic rainforest vegetation at Parque Estadual do Alto Ribeira (PETAR), southern São Paulo state (Brazil), was analyzed, in order to reconstruct the history of the local vegetation over the last 2500 years. Elemental (Total Organic Carbon TOC and Total Organic Nitrogen), isotopic (C and N), pollen analysis and radiocarbon dating were integrated on this work. Also was made a comparison of two protocols for Quaternary pollen chemical treatment. The tested protocols were proposed by Faegri and Iversen, 1989 (Protocol 2) and by Colinvaux et al., 1999 (Protocol 1). The comparison methods developed in this study checked the protocols performance on the quantity of palinomorphs and of organic matter found in 450 random areas of microscope slides of each protocol. The time consuming, laboratory routine, costs and residue production by the protocols were considered for comparison. Five samples were used for comparison and the Protocol 1 showed an average of 10% less organic matter and more palinomorphs than Protocol 2. According to the isotopic and pollen results, the study area vegetation maintained as a forest for the last 2500 years BP. \'delta\'13C values of -29%o indicated the presence of C3 plants during all the sediment study and a isotopic enrichment (- 24,9%o) was observed between 1650 and 1480 yrs BP. Pollen analysis suggested the occurrence of colder climatic conditions between 2550 and 2000 yrs BP and a warmer and humid period was suggested between 1000 and 680 yrs BP. Charcoal particles were found since 2550 yrs BP indicating paleofire probably associated to the human activities

L’œuvre de Tite-Live propose une histoire de la Res publica romaine depuis sa naissance jusqu’au tournant du premier siècle av. J.-C. où, selon les termes de l’auteur, « l’État se détruit sous l’effet de ses propres forces ». Au sortir d’une période de guerres civiles qui bouleversa en profondeur les repères politiques et sociaux, il s’agit pour l’historien de redéfinir l’identité politique de Rome en puisant dans les grands exemples du passé, à une époque où Auguste, en ramenant la paix, propose aussi, avec le Principat, un nouveau modèle d’exercice du pouvoir. Cette étude propose de relire l’Ab Vrbe condita comme une réflexion sur le pouvoir, un « discours », à une époque de profondes mutations. Retraçant le passé de la ville, l’historien exprime une pensée politique cohérente à travers ses commentaires, ses choix narratifs, et les discours qu’il attribue à différents personnages historiques. Celle-ci est le plus souvent proche de celle de Cicéron qui, du De Republica au De Officiis, offrait un cadre philosophique à la réflexion sur les institutions et les devoirs de l’homme d’État. Mais Tite-Live se la réapproprie en l’enrichissant des préoccupations politiques de son époque. Son récit de l’histoire de Rome s’inscrit principalement dans une défense de la libertas du peuple romain menacée par l’émergence d’un pouvoir personnel. Dans chaque situation, l’historien insiste sur les rapports complexes du dirigeant avec les institutions de la cité et le peuple de Rome. Par la mise en relation des exempla et des discours, Tite-Live propose un modèle de gouvernement unifié et cohérent fondé sur les vertus des dirigeants du passé et les valeurs collectives du peuple romain. / Livy’s body of work presents a history of the Roman Res publica from its beginnings to the turn of the first century. Civil wars had then deeply shaken the political and socials benchmarks and, while Augustus, after bringing peace back, was trying to impose a new political model with the Principate, it was the historian’s role to redefine Rome’s political identity through the use of well-known examples from the past. Livy’s From the Founding of the City may thus be read as a discourse about Roman power in a period of deep political change. The historian, as he tells the story of the city’s past, makes comments, narrative choices, and inserts into the historical figures’ speeches general remarks which help in many ways to grasp his political thinking. Most of the time, this thoughts are close to what can be read in Cicero’s political treatises. Cicero’s De Republica and De Officiis actually offered a philosophical frame of reference to political thinking, concerning the state institutions and the duties of state leaders. However, Livy develops his own theory and adds to Cicero’s political thought considerations on issues specific to his own time. Livy mainly defends the libertas of the Roman people against the emergence of personal power. In each and every situation, Livy sheds light on the complex relationships between the leaders and the state institutions and between the leaders and the Roman people. Linking exempla and speeches, Livy suggests a stable and coherent leadership model based upon the virtues of past political leaders and the collective principles of the Roman people.