A profinite approach to complete bifix decodings of recurrent languages

We approach the study of complete bifix decodings of (uniformly) recurrent languages with the help of the free profinite monoid. We show that the complete bifix decoding of a uniformly recurrent language $F$ by an $F$-charged rational complete bifix code is uniformly recurrent. An analogous result is obtained for recurrent languages.Comment: Original Manuscript of article to be published by De Gruyter in Forum Mathematicum. The last section of the version in Forum Mathematicum is very different, as there it is not proved that the Sch\"utzenberger group is an invariant of eventual conjugacy (the argument in the Original Manuscript had a flaw), but only that its maximal pronilpotent quotient is invariant by eventual conjugac

Groupes de retour de shifts ultimement dendriques

Since 2015, dendric shifts (a generalisation of Sturmian words) have been widely studied. One of the results concerning these shift spaces is the return theorem. It describes the groups generated by the return words of a dendric shift. The proof uses the fundamental group of the Rauzy graph of the shift space. Later, eventually dendric shifts were introduced. They are of utmost importance because, unlike dendric shifts, they are stable under conjugacy. This key feature makes eventual dendricity a dynamical property. It seems natural to investigate if results similar to the return theorem hold in the eventually dendric case. The aim of this presentation is to introduce return groups and dendricity. It will also contain new results concerning the return theorem in the case of eventually dendric shifts and showcase the tools used to prove it

On the group of a rational maximal bifix code

We give necessary and sufficient conditions for the group of a rational maximal bifix code $Z$ to be isomorphic with the $F$-group of $Z\cap F$, when $F$ is recurrent and $Z\cap F$ is rational. The case where $F$ is uniformly recurrent, which is known to imply the finiteness of $Z\cap F$, receives special attention. The proofs are done by exploring the connections with the structure of the free profinite monoid over the alphabet of $F$

A study of dendricity through the lens of morphisms

Dendric languages were introduced a decade ago as a generalization of both Arnoux-Rauzy languages and codings of regular interval exchange transformations. Right away, they were shown to possess strong algebraic properties, as well as being stable under fundamental operations. A few years later, Dolce and Perrin studied the more general notion of eventual dendricity. In this these, we explore another aspect of (eventual) dendricity and delve deeper into the link with morphisms. We mainly study for aspects: the evolution of the factor complexity when applying a morphism, the morphisms preserving dendricity for all languages, a characterization of the preservation of dendricity for some specific morphisms and an S-adic characterization of (eventually) dendric languages leading to decidability in the morphic case.Les langages dendriques ont été introduits il y a une dizaine d'années comme étant une généralisation à la fois des langages Sturmiens, des langages d'Arnoux-Rauzy et des codages d'échanges d'intervalles réguliers. Dès le début, leur lien fort avec certaines propriétés algébriques ainsi que leur stabilité pour des opérations fondamentales ont été démontrés. Quelques années plus tard, Dolce et Perrin se sont intéressés à une notion plus générale : l'ultime dendricité et ont également des résultats de stabilité importants. Dans cette thèse, nous nous attardons sur un autre aspect de (l'ultime) dendricité en explorant ses liens avec les morphismes. Nous nous intéressons plus particulièrement à trois questions : l'évolution de la complexité en facteur lors de l'application d'un morphisme, les morphismes préservant le caractère dendrique pour tous les langages, la description complète de la préservation du caractère dendrique pour des morphismes spécifiques et la caractérisation S-adique des langages (ultimement) dendriques, ce qui mène à la décidabilité du caractère (ultimement) dendrique dans le cas morphique

Traumatic Brain Injury

As many of you already know, traumatic brain injury (TBI) is a growing public health problem of substantial proportions. More than 50 million TBIs occur internationally each year. Across all ages, TBI represents 30–40% of all injury-related deaths, and neurological injury is projected to remain the most important cause of disability from neurological disease until 2030. Severe TBI has a high mortality rate, estimated at 30–40% in observational studies on unselected populations. Survivors experience a substantial burden of physical, psychiatric, emotional, and cognitive disabilities, which disrupt the lives of individuals and their families, and impose huge costs on society. Wide variations in the clinical manifestations of TBI are attributable to the complexity of the brain and to the pattern and extent of damage. Over the past few years, a number of multicenter studies on the topic have emerged, helping to provide a better understanding of the condition. However, it is also clear that much remains to be learned

Ethnoarchaeology of the middle Tanana Valley, Alaska

Thesis (Ph.D.) University of Alaska Fairbanks, 2020This study explores the shifting anthropological constructs of identity for the Middle Tanana people through time. It first summarizes this theme through contemporary regional Native American internal and external influences. A discussion is then given on how these constructs became formed through historical processes. Next, it provides an in-depth look into how identity became shaped prior to the Euro-American influence through an ethnographic reconstruction. These are framed in a way to form relevant hypotheses to study the regional prehistoric archaeological record. The Historical Linguistics analytical approach used here confirms that there is very little, if any, evidence in the languages of the Tanana Valley from any non-Dene or other hypothetical pre-existing linguistic group. Language forms an integral unit of community identity. This study also frames the linguistic argument for deep regional cultural antiquity and identity through an extensive survey of traditional place names. A brief comparative study of the processes and effects of the incursion of the Indo-European languages into traditional Dene territory is discussed to demonstrate this argument. Next, the research explores the middle and later Holocene archaeological record of the Shaw Creek basin, located deep within the Middle Tanana homelands, using innovative approaches framing traditional Optimal Foraging theory arguments through the lens of Complexity theory. It focuses on the household archaeology and spatial artifact analysis of two archaeological sites, Swan Point (three Holocene components) and Pickupsticks (one Holocene component). In these case studies, cultural identity analogs, social structure, and agency are discussed using the material cultural record as a proxy. Finally, a dynamic, seasonal, ecological landscape-use model informed by predator/prey interactions is used to inform hypothetical human foraging movements. It models decision-making and risk-mitigation processes through resource shortfalls, predicting raw materials' movements from their source locations to their discard locations at these two archaeological sites. The conclusions support the theory that Dene presence in the Middle Tanana Valley is an ancient phenomenon that has at least early Holocene roots. Further, the period between 2,000 and 1,000 years ago appears to have been a critical period of additional cultural intensification processes. The processes leading to the development of the Athabascan archaeological tradition are considered to be the result of demographic expansion, increased territoriality, and a critical reinterpretation of the roles of kinship and non-related partnerships.Tanana Chief's Conference, Otto William Geist Fund, David and Rachel Hopkins FellowshipChapter 1: Introduction -- Chapter 2: Theoretical methods -- Chapter 3: The Middle Tanana People: modern and historical identity -- Chapter 4: The ethnographic reconstruction of the past: The Middle Tanana Valley -- Chapter 5: Historical linguistic and ethno-geographic perspectives of the Alaskan Dene -- Chapter 6: Archaeological and ecological reconstructions: The Holocene epoch -- Chapter 7: The project history of the Swan Point and Pickupsticks archaeological sites -- Chapter 8: Radiocarbon analysis -- Chapter 9: Feature analysis -- Chapter 10: Spatial artifact analysis -- Chapter 11: Inferences from top-predator data for modeling seasonal lithic procurement strategies as a dynamic system -- Chapter 12: Discussion -- Chapter 13: Conclusion -- References -- Appendix

A pedoanthracological and palynological approach to study man-climate-ecosystem interactions during the Holocene in Persepolis basin (SW-Iran)

It is generally discussed and accepted that the climate, human, and the vegetation are in a close interaction in southwest Asia since the presence of the human beings in the area. In this regard, Iran and specifically the Zagros Mountains were an important part of the Fertile Crescent. This area plays a critical role as the progenitor sanctuary for early civilizations in SW Asia. For this strategic geographical position and considering a near-continuous history of human occupation (since Neolithic times 7000 BC), the Persepolis basin has been selected for a multidisciplinary palaeoenvironmental study in the frame of Paleo-Persepolis project conducted by a French-German institutional consortium and financed by the ANR and DFG. This basin has witnessed the presence and emergence of several great civilizations (Elamite, Achaemenid–Persian, and Sasanian). In addition to climatic changes, such civilizations left substantial impacts on the environment by their social structures as well as different strategies in exploiting the resources. The present study contributes to the Paleo-Persepolis project and focuses on studying the vegetation dynamics and fire history of the Persepolis and surrounding areas. This thesis aims to investigate the past vegetation changes of the basin during the Holocene epoch within the human-climate-ecosystem nexus of Southwestern Zagros. The present study resulted in the first wood anatomy and charcoal identification keys beside the reference collections for the major arboreal taxa of the Persepolis basin. This study was crucial to build a background for reconstructing the historical woody vegetation applying a (pedo-)anthracalogical approach. Moreover, a high-resolution palynological investigation on a Holocene sediment core from Lake Maharlou, emphasizes on revealing the role of man in modifying the natural vegetation of the area. Palynological survey on this lake provided the first pollen evidence of Punica granatum suggesting the large-scale pomegranate plantations, a fact that is supported by the historical documents. Significant increases in agriculture and urban development during Persian empires and Early Islamic dynasties also suggested by this study. The present thesis addressed the history of arboriculture in ancient Iran using palynological evidence as well as a summary of historical and archaeological supporting evidence. In addition, the thesis presents the results of the first fire history reconstruction in the interior parts of the Iranian Plateau and the Zagros Mountains during the last ~ 3700 years. It addresses the drivers of the significant fire episodes, using macroscopic charcoal records from the Lake Maharlou. Furthermore, the present study illustrates the results of an anthracological survey on archaeobotanical wood charcoal that remains from a prehistoric site of Tepe Rahmatabad in the Persepolis basin. The present palynological study and fire history reconstruction reveals the vegetation changes in Maharlou Lake basin during the last ~ 3700 years. In addition, with the anthracological study of Tepe Rahmatabad we represent older evidence of local changes in landscape and vegetation during the Pre-Pottery Neolithic to Chalcolithic (~ 10000 – 6000 yr BP) periods. The obtained results demonstrated the role of anthropogenic activities in modifying the landscape of the basin, which enhanced by climatic changes