The role of emerging elites in the formation and development of communities after the fall of the Roman Empire

Elites played a pivotal role in the formation of post-Roman Europe on both macro- and microlevels during the Early Medieval period. History and archaeology have long focused on their description and identification based on written sources or through their archaeological record. We provide a different perspective on this topic by integrating paleogenomic, archaeological, and isotopic data to gain insights into the role of one such elite group in a Langobard period community near Collegno, Italy dated to the 6-8th centuries CE. Our analysis of 28 newly sequenced genomes together with 24 previously published ones combined with isotope (Sr, C, N) measurements revealed that this community was established by and organized around a network of biologically and socially related individuals likely composed of multiple elite families that over time developed into a single extended pedigree. The community also included individuals with diverse genetic ancestries, maintaining its diversity by integrating newcomers and groups in later stages of its existence. This study highlights how shifts in political power and migration impacted the formation and development of a small rural community within a key region of the former Western Roman Empire after its dissolution and the emergence of a new kingdom. Furthermore, it suggests that Early Medieval elites had the capacity to incorporate individuals from varied backgrounds and that these elites were the result of (political) agency rather than belonging to biologically homogeneous groups

How old are you now? A new ageing method for nonadults based on dental wear

The main aim of this study is to present a novel method of nonadult (ca. 1–19 years) age‐at‐death estimation using the dental wear of deciduous, mixed deciduous‐permanent, and permanent dentitions, including the incisors, canines, premolars, and first and second molars. The stage‐based method is derived from degrees of dental wear in known‐age (n = 39) and estimated‐age (n = 11) nonadults containing 951 teeth from the predominately 19th century cemetery of Middenbeemster, The Netherlands. The need for such a method is warranted in cases where dental development and/or eruption cannot be assessed for age‐at‐death estimation. As well, by establishing a baseline for normal age‐related nonadult tooth wear, users may better document wear that could be due to extramasticatory behaviours. The regression analysis reveals a strong quadratic correlation—F(2, 47) = 555.1, p R2 = .95, standard error of the estimate = 1.14, residual sum of squares (RSS) = 68.89, predicted residual error sum of squares (PRESS) = 77.67—between age and wear and multivariate adaptive regression splines (R2 = .95, generalised cross validation = 1.67, RSS = 67.68, PRESS = 89.34), which are used to develop an R‐package that users may employ to estimate age‐at‐death from dental wear. The accuracy of this method (78–98%) is evaluated using leave‐one‐out cross‐validation. Analyses of males versus females, deciduous versus permanent, upper versus lower, and anterior versus posterior teeth revealed no apparent reason to warrant separate methods for these groups of separated dentitions. This method fills a disciplinary gap in the understudied area of deciduous and nonadult dental wear and hopes to stimulate much future research. With the R‐package, we also provide the foundation and framework for the development of additional reference populations across different spatiotemporal contexts, to make the method more widely applicable. Bioarchaeolog

The genetic history of the Southern Arc: a bridge between West Asia and Europe

By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread southward into the Balkans and across the Caucasus into Armenia, where they left numerous patrilineal descendants. Anatolia was transformed by intra–West Asian gene flow, with negligible impact of the later Yamnaya migrations. This contrasts with all other regions where Indo-European languages were spoken, suggesting that the homeland of the Indo-Anatolian language family was in West Asia, with only secondary dispersals of non-Anatolian Indo-Europeans from the steppe

Zdefiniowanie obciążeń działających na tuleję zagęszczającą brykieciarki

Compacting sleeves that are components of briquette presses undergo time variable loadings that are characteristic of the briquette press operation. These sleeves have a specific fatigue life; and, after having worked for a certain period of time, they fail to operate. In order to continue the operation process, they need to be replaced with new ones. Manufacturers of briquette presses define the life of compacting sleeves to be approximately 2 thousand hours. However, it often happens that the life of such a sleeve is significantly shorter than the expected one. This work presents calculation models for a sleeve with length 380 mm and diameter 50 mm (diameter of briquette) under a pressure with maximum value 16 MPa. The presented models allow one to determine stresses for unloading and loading with the use of a numerical method. These stresses can be used for the estimation of the fatigue life of operating sleeves or for the dimensioning of newly designed sleeves.Tuleje zagęszczające pracujące w zespole roboczym brykieciarek poddawane są zmiennym w czasie obciążeniom wynikającym z charakteru pracy brykieciarki. Tuleje te posiadają określoną trwałość zmęczeniową i po przepracowaniu pewnej ilości godzin zostają zniszczone i w celu dalszej eksploatacji brykieciarki należy je wymieniać na nowe. Producenci brykieciarek najczęściej określają trwałość tuli zagęszczających na około 2 tys. godzin. Bardzo często okazuje się jednak, że trwałość takiej tulei jest zdecydowanie niższa od zakładanej. W niniejszej pracy przedstawiono modele obliczeniowe dla tulei o długości 380 mm i średnicy roboczej 50 mm (średnica brykietu). Przedstawione modele umożliwiają określenie metodą numeryczną naprężeń przy odciążeniu oraz obciążeniu. Naprężenia te następnie mogą być wykorzystane do szacowania trwałości zmęczeniowej pracujących tulei lub do wymiarowania nowo projektowanych tulei

Wpływ parametrów spawania laserowego stali typu DUPLEX na trwałość zmęczeniową złączy z usuniętym karbem geometrycznym w postaci lica i grani

A geometrical and a structural notch effect have the main influence on the local stress and strain concentration in the welded joints. These factors have a significant influence on the fatigue life of welded joints. This paper presents the results of the fatigue life tests of laser-welded joints of DUPLEX 2205 steel, taking into account the structural notch. The geometric notch in the form of face and root was removed. The Nd-YAG disk laser was used to weld butt joints. The welding process was conducted using two different parameters of welding without using additional material. The parameters were chosen based on previous studies (according to PN-EN ISO 15614-11:2005). In the study of the fatigue life of laser-welded joints, the geometric notch was ground out. Based on this research, the effect of welding parameters on the fatigue life was not observed. The fatigue cracks initiation and propagation occurred in the base materials in all cases. In addition, the results of the fatigue life of welded joints were related to the fatigue life of the samples taken from the parent material.W połączeniach spawanych występują lokalne spiętrzenia odkształceń spowodowane głównie geometrią złącza (karb geometryczny) jak również niejednorodnością strukturalną (karb strukturalny). Czynniki te mają znaczący wpływ na trwałość zmęczeniową złącza. W niniejszej pracy przedstawiono wyniki prób zmęczeniowych złączy spawanych laserowo ze stali typu DUPLEX 2205 z uwzględnieniem karbu strukturalnego. Karb geometryczny w postaci lica i grani spoiny usunięto. Złącza spawane czołowo wykonano przy użyciu lasera dyskowego typu Nd-YAG bez materiału dodatkowego dla dwóch różnych parametrów spawania. Parametry zostały dobrane na podstawie wcześniejszych badań (zgodnie z PN-EN ISO 15614-11: 2005) przeprowadzonych na złączach wykonanych kilkunastoma różnymi parametrami spawania. W badaniach trwałości zmęczeniowej połączeń spawanych laserowo pominięto karb geometryczny. Pozwoliło to na określenie optymalnych parametrów spawania laserowego stali typu DUPLEX 2205 ze względu na trwałość zmęczeniową powstałej podczas spawania struktury złącza. Dodatkowo otrzymane wyniki trwałości zmęczeniowych złączy spawanych odniesiono do trwałości zmęczeniowej próbek pobranych z materiału rodzimego

Time to replacement passengers at bus stations in Bydgoszcz

W artykule przedstawiono wyniki obserwacji czasu wymiany potoków pasażerskich na przystankach autobusowych na terenie Bydgoszczy. Ponadto przeanalizowano czynniki, które mogą mieć bezpośredni i pośredni wpływ na długość trwania wymiany podróżnych wysiadających z pojazdu oraz podróżnych wsiadających do pojazdu.The article presents observation results of time to replacement passengers at bus stations in Bydgoszcz. In addition the factors, which may have an impact on the length of the duration of replacement passengers getting off vehicle and getting on vehicle were analyzed

Much ado about nothing: assessing the impact of the 4.2 kya event on human subsistence patterns in northern Mesopotamia using stable isotope analysis

The effects of the 4.2 kya climatic event on northern Mesopotamia have been the subject of significant scholarly debate, with the notion of a megadrought that forced local populations to migrate attracting particular attention. Here, the authors analyse stable carbon (δ13C) and nitrogen (δ15N) isotopes in human tooth and bone samples to assess trends in subsistence practice at three sites in Syria before, during and after the presumed megadrought event. Despite the proximity of the sites, isotopic differences between them are more significant than diachronic change. Combined with other archaeological evidence, these results indicate a continuity in subsistence patterns, with no indication of disruption associated with the 4.2 kya event.- The 4.2 kya event in northern Mesopotamia - Reconstructing subsistence using bone and tooth collagen δ13C and δ15N values - Materials and methods - Results - Discussion - Conclusion

Markov model of the operation and maintenance process of farm tractors

Efektywna i racjonalna analiza złożonych procesów eksploatacji obiektów technicznych wymaga zastosowania różnego rodzaju metod modelowania, w tym modeli matematycznych i symulacyjnych. W badaniach do opisu rzeczywistego procesu eksploatacji ciągników rolniczych opracowano zdarzeniowy model procesu eksploatacji, a następnie zbudowano model matematyczny z zastosowaniem teorii procesów Markowa. Na podstawie otrzymanych wyników dokonano analizy rozpatrywanego procesu eksploatacji obiektów technicznych.An effective and rational analysis of complex processes of technical object operation and maintenance requires the use of various types of modeling methods, including mathematical and simulation models. In this paper, in order to describe the actual process of farm tractor operation and maintenance, an event model of the operation and maintenance process was developed, and then a mathematical model of this process was built using the theory of Markov processes. On the basis of the obtained results, the considered operation and maintenance process was analyzed

On strong generation of B(ℋ) by two commutative C*-algebras

The algebra B(ℋ) of all bounded operators on a Hilbert space ℋ is generated in the strong operator topology by a single one-dimensional projection and a family of commuting unitary operators with cardinality not exceeding dim ℋ. This answers Problem 8 posed by W. Żelazko in [6]