163 research outputs found
Mitochondrial DNA analysis of eneolithic trypillians from Ukraine reveals neolithic farming genetic roots
The agricultural revolution in Eastern Europe began in the Eneolithic with the Cucuteni-Trypillia culture complex. In Ukraine, the Trypillian culture (TC) existed for over two millennia (ca. 5,400–2,700 BCE) and left a wealth of artifacts. Yet, their burial rituals remain a mystery and to date almost nothing is known about the genetic composition of the TC population. One of the very few TC sites where human remains can be found is a cave called Verteba in western Ukraine. This report presents four partial and four complete mitochondrial genomes from nine TC individuals uncovered in the cave. The results of this analysis, combined with the data from previous reports, indicate that the Trypillian population at Verteba carried, for the most part, a typical Neolithic farmer package of mitochondrial DNA (mtDNA) lineages traced to Anatolian farmers and Neolithic farming groups of central Europe. At the same time, the find of two specimens belonging to haplogroup U8b1 at Verteba can be viewed as a connection of TC with the Upper Paleolithic European populations. At the level of mtDNA haplogroup frequencies, the TC population from Verteba demonstrates a close genetic relationship with population groups of the Funnel Beaker/ Trichterbecker cultural complex from central and northern Europe (ca. 3,950–2,500 BCE)
The Effect of Caffeine on the Bacterial Populations in a Freshwater Aquarium System
Caffeine is becoming a common chemical found in the environment but, little research has been done to understand the environmental effects of caffeine, including dissolved caffeine in aquatic systems. The goal of this research study was to begin to understand how caffeine may interact with aquatic environment, using the bacteria of the genus Pseudomonas, commonly found in the aquatic habitat. We found that Pseudomonas shows an increase in growth when exposed to caffeine, which results in a change in spectrophotometric absorbance, increase in bacterial colony count in the presence of caffeine, and in bio-film like sheen appearing on the glass of the experimental aquarium. Along with the increased bacterial growth, a dramatic increase in ammonia concentrations was observed. Ammonia is toxic to fish, and can be correlated with the metabolic activity of the Pseudomonas bacteria, making the caffeinated environment toxic for aquatic life
The Origins and Chronology of the Usatove Culture
Usatove was an important southeast European culture, part of Gimbutas’ kurgan cultures, that connected the world of farmers of Old Europe with the rising influence of steppe nomads at the Eneolithic–Bronze Age transition. While the Usatove culture is currently placed within the late Eneolithic–Early Bronze Age chronological period, emerging evidence suggests the culture formed genetically and culturally in the early part of the 4th millennium BCE. We propose that the biological and cultural foundations of Usatove lie at the juncture of the Suvorove–Novodanylivka branch of the Seredny Stig complex of the North Pontic Steppe, the Trypillian farmers of southeast Europe, with influences from Varna–Karanovo VI–Gumelniţa and late Stone Age cultures of the North Caucasus
Paleo-Balkan and Slavic Contributions to the Genetic Pool of Moldavians
Moldova has a rich historical and cultural heritage, which may be reflected in the current genetic makeup of its population.
To date, no comprehensive studies exist about the population genetic structure of modern Moldavians. To bridge this gap
with respect to paternal lineages, we analyzed 37 binary and 17 multiallelic (STRs) polymorphisms on the non-recombining
portion of the Y chromosome in 125 Moldavian males. In addition, 53 Ukrainians from eastern Moldova and 54 Romanians
from the neighboring eastern Romania were typed using the same set of markers. In Moldavians, 19 Y chromosome
haplogroups were identified, the most common being I-M423 (20.8%), R-M17* (17.6%), R-M458 (12.8%), E-v13 (8.8%), RM269*
and R-M412* (both 7.2%). In Romanians, 14 haplogroups were found including I-M423 (40.7%), R-M17* (16.7%), RM405
(7.4%), E-v13 and R-M412* (both 5.6%). In Ukrainians, 13 haplogroups were identified including R-M17 (34.0%), I-M423
(20.8%), R-M269* (9.4%), N-M178, R-M458 and R-M73 (each 5.7%). Our results show that a significant majority of the
Moldavian paternal gene pool belongs to eastern/central European and Balkan/eastern Mediterranean Y lineages.
Phylogenetic and AMOVA analyses based on Y-STR loci also revealed that Moldavians are close to both eastern/central
European and Balkan-Carpathian populations. The data correlate well with historical accounts and geographical location of
the region and thus allow to hypothesize that extant Moldavian paternal genetic lineages arose from extensive recent
admixture between genetically autochthonous populations of the Balkan-Carpathian zone and neighboring Slavic group
Prva analiza izotopov in novi radiokarbonski datumi poljedelcev kulture Tripolje iz jame Verteba, Bilche Zolote, Ukrajina
This paper presents an analysis of human and animal remains from Verteba cave, near Bilche Zolote, western Ukraine. This study was prompted by a paucity of direct dates on this material and the need to contextualise these remains in relation both to the transition from hunting and gathering to farming in Ukraine, and their specific place within the Cucuteni-Trypillia culture sequence. The new absolute dating places the remains studied here in Trypillia stages BII/CI at c. 3900–3500 cal BC, with one individual now redated to the Early Scythian period. As such, these finds are even more exceptional than previously assumed, being some of the earliest discovered for this culture. The isotope analyses indicate that these individuals are local to the region, with the dietary stable isotopes indicating a C3 terrestrial diet for the Trypillia-period humans analysed. The Scythian period individual has δ13C ratios indicative of either c. 50% marine, or alternatively C4 plant inputs into the diet, despite δ18O and 87Sr/86Sr ratios that are comparable to the other individuals studied.V članku predstavljamo analizo človeških in živalskih ostankov iz jame Verteba blizu kraja Bilche Zolote v zahodni Ukrajini. Študija je nastala zaradi pomanjkljivega števila datumov iz teh ostankov in iz potrebe po kontekstualiziranju najdb v odnosu tako do prehoda iz lovsko-nabiralniške družbe v poljedelsko v Ukrajini kot tudi glede na poseben prostor, ki ga imajo te najdbe znotraj kulturne sekvence Cucuteni-Tripolje. Novi absolutni datumi postavljajo ostanke faze BII/CI kulture Tripolje v čas ok. 3900–3500 pr. n. št., medtem ko je eden od pokopov zdaj ponovno datiran v čas zgodnjega skitskega obdobja, kar pomeni, da gre za ene najstarejših najdb te kulture. Analiza izotopov kaže, da so bili pokojni lokalni prebivalci regije, analiza stabilnih izotopov pa kaže na C3 kopensko prehrano ljudi v času kulture Tripolje. Pokop iz skitskega obdobja kaže glede na δ13C vrednosti na ok. 50 % morske prehrane, oziroma na C4 rastline, vključene v prehrano, kljub temu da so deleži izotopov δ18O in 87Sr/86Sr primerljivi s preostalimi vzorci ljudi na najdišču
Polaritonic Fourier crystal
Polaritonic crystals - periodic structures where the hybrid light-matter
waves called polaritons can form Bloch states - promise a deeply
subdiffractional nanolight manipulation and enhanced light-matter interaction.
In particular, polaritons in van der Waals materials boast extreme field
confinement and long lifetimes allowing for the exploitation of wave phenomena
at the nanoscale. However, in conventionally patterned nanostructures,
polaritons are prone to severe scattering loss at the sharp material edges,
making it challenging to create functional polaritonic crystals. Here, we
introduce a new concept of a polaritonic Fourier crystal based on a harmonic
modulation of the polariton momentum in a pristine polaritonic waveguide with
minimal scattering. We employ hexagonal boron nitride (hBN) and near-field
imaging to reveal a neat and well-defined band structure of phonon-polaritons
in the Fourier crystal, stemming from the dominant excitation of the
first-order Bloch mode. Furthermore, we show that the fundamental Bloch mode
possesses a polaritonic bandgap even in the relatively lossy naturally abundant
hBN. Thus, our work provides a new paradigm for polaritonic crystals essential
for enhanced light-matter interaction, dispersion engineering, and nanolight
guiding
Interactions between Trypillian farmers and North Pontic forager-pastoralists in Eneolithic central Ukraine
The establishment of agrarian economy in Eneolithic East Europe is associated with the
Pre-Cucuteni-Cucuteni-Trypillia complex (PCCTC). PCCTC farmers interacted with Eneolithic forager-pastoralist groups of the North Pontic steppe as PCCTC extended from the
Carpathian foothills to the Dnipro Valley beginning in the late 5th millennium BCE. While the cultural interaction between the two groups is evident through the Cucuteni C pottery style that carries steppe influence, the extent of biological interactions between Trypillian farmers
and the steppe remains unclear. Here we report the analysis of artefacts from the late 5th millennium Trypillian settlement at the Kolomiytsiv Yar Tract (KYT) archaeological complex in central Ukraine, focusing on a human bone fragment found in the Trypillian context at KYT. Diet stable isotope ratios obtained from the bone fragment suggest the diet of the KYT individual to be within the range of forager-pastoralists of the North Pontic area. Strontium
isotope ratios of the KYT individual are consistent with having originated from contexts of the Serednii Stih (Sredny Stog) culture sites of the Middle Dnipro Valley. Genetic analysis of the KYT individual indicates ancestry derived from a proto-Yamna population such as Serednii Stih. Overall, the KYT archaeological site presents evidence of interactions between Trypillians and Eneolithic Pontic steppe inhabitants of the Serednii Stih horizon and suggests a potential for gene flow between the two groups as early as the beginning of the 4th
millennium BCE
Nanoscale-confined Terahertz Polaritons in a van der Waals Crystal
Electromagnetic field confinement is crucial for nanophotonic technologies,
since it allows for enhancing light-matter interactions, thus enabling light
manipulation in deep sub-wavelength scales. In the terahertz (THz) spectral
range, radiation confinement is conventionally achieved with specially designed
metallic structures - such as antennas or nanoslits - with large footprints due
to the rather long wavelengths of THz radiation. In this context, phonon
polaritons - light coupled to lattice vibrations - in van der Waals (vdW)
crystals have emerged as a promising solution for controlling light beyond the
diffraction limit, as they feature extreme field confinements and low optical
losses. However, experimental demonstration of nanoscale-confined phonon
polaritons at THz frequencies has so far remained elusive. Here, we provide it
by employing scattering-type scanning near-field optical microscopy (s-SNOM)
combined with a free-electron laser (FEL) to reveal a range of low-loss
polaritonic excitations at frequencies from 8 to 12 THz in the vdW
semiconductor . We visualize THz polaritons with i) in-plane
hyperbolic dispersion, ii) extreme nanoscale field confinement (below
) and iii) long polariton lifetimes, with a lower limit of > 2
ps
Planar refraction and lensing of highly confined polaritons in anisotropic media
Refraction between isotropic media is characterized by light bending towards the normal to the boundary when passing from a low- to a high-refractive-index medium. However, refraction between anisotropic media is a more exotic phenomenon which remains barely investigated, particularly at the nanoscale. Here, we visualize and comprehensively study the general case of refraction of electromagnetic waves between two strongly anisotropic (hyperbolic) media, and we do it with the use of nanoscale-confined polaritons in a natural medium: alpha-MoO3. The refracted polaritons exhibit non-intuitive directions of propagation as they traverse planar nanoprisms, enabling to unveil an exotic optical effect: bending-free refraction. Furthermore, we develop an in-plane refractive hyperlens, yielding foci as small as lambdap/6, being lambdap the polariton wavelength (lambda0/50 compared to the wavelength of free-space light). Our results set the grounds for planar nano-optics in strongly anisotropic media, with potential for effective control of the flow of energy at the nanoscale.G.Á.-P. and J.T.-G. acknowledge support through the Severo Ochoa Program from the Government of the Principality of Asturias (nos. PA-20-PF-BP19-053 and PA-18-PF-BP17-126, respectively). S.X. acknowledges the support from Independent Research Fund Denmark (Project No. 9041-00333B). B.C. acknowledges the support from VILLUM FONDEN (No. 00027987). The Center for Nanostructured Graphene is sponsored by the Danish National Research Foundation (Project No. DNRF103.) K.V.V. and V.S.V. gratefully acknowledge the financial support from the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 075-15-2021-606). J.M.-S. acknowledges financial support through the Ramón y Cajal Program from the Government of Spain (RYC2018-026196-I). A.Y.N. and J.I.M. acknowledge the Spanish Ministry of Science, Innovation and Universities (national projects MAT201788358-C3-3-R and PID2019-104604RB/AEI/10.13039/501100011033). R.H. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (national project RTI2018-094830-B-100 and the project MDM-2016-0618 of the Marie de Maeztu Units of Excellence Program) and the Basque Government (grant No. IT1164-19). A.Y.N. also acknowledges the Basque Department of Education (grant no. PIBA-2020-1-0014). P.A.-G. acknowledges support from the European Research Council under starting grant no. 715496, 2DNANOPTICA and the Spanish Ministry of Science and Innovation (State Plan for Scientific and Technical Research and Innovation grant number PID2019-111156GB-I00)
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