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1.
Nature ; 599(7886): 616-621, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34759322

RESUMO

The origin and early dispersal of speakers of Transeurasian languages-that is, Japanese, Korean, Tungusic, Mongolic and Turkic-is among the most disputed issues of Eurasian population history1-3. A key problem is the relationship between linguistic dispersals, agricultural expansions and population movements4,5. Here we address this question by 'triangulating' genetics, archaeology and linguistics in a unified perspective. We report wide-ranging datasets from these disciplines, including a comprehensive Transeurasian agropastoral and basic vocabulary; an archaeological database of 255 Neolithic-Bronze Age sites from Northeast Asia; and a collection of ancient genomes from Korea, the Ryukyu islands and early cereal farmers in Japan, complementing previously published genomes from East Asia. Challenging the traditional 'pastoralist hypothesis'6-8, we show that the common ancestry and primary dispersals of Transeurasian languages can be traced back to the first farmers moving across Northeast Asia from the Early Neolithic onwards, but that this shared heritage has been masked by extensive cultural interaction since the Bronze Age. As well as marking considerable progress in the three individual disciplines, by combining their converging evidence we show that the early spread of Transeurasian speakers was driven by agriculture.


Assuntos
Agricultura/história , Arqueologia , Genética Populacional , Migração Humana/história , Idioma/história , Linguística , China , Conjuntos de Dados como Assunto , Mapeamento Geográfico , História Antiga , Humanos , Japão , Coreia (Geográfico) , Mongólia
2.
Evol Hum Sci ; 4: e8, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37588906

RESUMO

[This corrects the article DOI: 10.1017/ehs.2020.18.].

3.
Front Bioeng Biotechnol ; 10: 895406, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091441

RESUMO

Brain tissue reconstruction posttraumatic injury remains a long-standing challenge in neurotransplantology, where a tissue-engineering construct (scaffold, SC) with specific biochemical properties is deemed the most essential building block. Such three-dimensional (3D) hydrogel scaffolds can be formed using brain-abundant endogenous hyaluronic acid modified with glycidyl methacrylate by employing our proprietary photopolymerisation technique. Herein, we produced 3D hyaluronic scaffolds impregnated with neurotrophic factors (BDNF, GDNF) possessing 600 kPa Young's moduli and 336% swelling ratios. Stringent in vitro testing of fabricated scaffolds using primary hippocampal cultures revealed lack of significant cytotoxicity: the number of viable cells in the SC+BDNF (91.67 ± 1.08%) and SC+GDNF (88.69 ± 1.2%) groups was comparable to the sham values (p > 0.05). Interestingly, BDNF-loaded scaffolds promoted the stimulation of neuronal process outgrowth during the first 3 days of cultures development (day 1: 23.34 ± 1.46 µm; day 3: 37.26 ± 1.98 µm, p < 0.05, vs. sham), whereas GDNF-loaded scaffolds increased the functional activity of neuron-glial networks of cultures at later stages of cultivation (day 14) manifested in a 1.3-fold decrease in the duration coupled with a 2.4-fold increase in the frequency of Ca2+ oscillations (p < 0.05, vs. sham). In vivo studies were carried out using C57BL/6 mice with induced traumatic brain injury, followed by surgery augmented with scaffold implantation. We found positive dynamics of the morphological changes in the treated nerve tissue in the post-traumatic period, where the GDNF-loaded scaffolds indicated more favorable regenerative potential. In comparison with controls, the physiological state of the treated mice was improved manifested by the absence of severe neurological deficit, significant changes in motor and orienting-exploratory activity, and preservation of the ability to learn and retain long-term memory. Our results suggest in favor of biocompatibility of GDNF-loaded scaffolds, which provide a platform for personalized brain implants stimulating effective morphological and functional recovery of nerve tissue after traumatic brain injury.

4.
Int J Circumpolar Health ; 80(1): 1925446, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34125008

RESUMO

This article focuses on the "second wave" of the COVID-19 pandemic in the Arctic and examines spatiotemporal patterns between July 2020 and January 2021. We analyse available COVID-19 data at the regional (subnational) level to elucidate patterns and typology of Arctic regions with respect to the COVID-19 pandemic. This article builds upon our previous research that examined the early phase of the COVID-19 pandemic between February and July 2020. The pandemic's "second wave" observed in the Arctic between September 2020 and January 2021 was severe in terms of COVID-19 infections and fatalities, having particularly strong impacts in Alaska, Northern Russia and Northern Sweden. Based on the spatiotemporal patterns of the "second wave" dynamics, we identified 5 types of the pandemic across regions: Shockwaves (Iceland, Faroe Islands, Northern Norway, and Northern Finland), Protracted Waves (Northern Sweden), Tidal Waves (Northern Russia), Tsunami Waves (Alaska), and Isolated Splashes (Northern Canada and Greenland). Although data limitations and gaps persist, monitoring of COVID-19 is critical for developing a proper understanding of the pandemic in order to develop informed and effective responses to the current crisis and possible future pandemics in the Arctic. Data used in this paper are available at https://arctic.uni.edu/arctic-covid-19.


Assuntos
Teste para COVID-19/estatística & dados numéricos , COVID-19/epidemiologia , Vigilância da População , Regiões Árticas , COVID-19/diagnóstico , Humanos , Incidência
5.
Front Bioeng Biotechnol ; 9: 783834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926429

RESUMO

Bioprinting emerges as a powerful flexible approach for tissue engineering with prospective capability to produce tissue on demand, including biomimetic hollow-core fiber structures. In spite of significance for tissue engineering, hollow-core structures proved difficult to fabricate, with the existing methods limited to multistage, time-consuming, and cumbersome procedures. Here, we report a versatile cell-friendly photopolymerization approach that enables single-step prototyping of hollow-core as well as solid-core hydrogel fibers initially loaded with living cells. This approach was implemented by extruding cell-laden hyaluronic acid glycidyl methacrylate hydrogel directly into aqueous solution containing free radicals generated by continuous blue light photoexcitation of the flavin mononucleotide/triethanolamine photoinitiator. Diffusion of free radicals from the solution to the extruded structure initiated cross-linking of the hydrogel, progressing from the structure surface inwards. Thus, the cross-linked wall is formed and its thickness is limited by penetration of free radicals in the hydrogel volume. After developing in water, the hollow-core fiber is formed with centimeter range of lengths. Amazingly, HaCaT cells embedded in the hydrogel successfully go through the fabrication procedure. The broad size ranges have been demonstrated: from solid core to 6% wall thickness of the outer diameter, which was variable from sub-millimeter to 6 mm, and Young's modulus ∼1.6 ± 0.4 MPa. This new proof-of-concept fibers photofabrication approach opens lucrative opportunities for facile three-dimensional fabrication of hollow-core biostructures with controllable geometry.

6.
Evol Hum Sci ; 22020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35663512

RESUMO

The origin of the Xiongnu and the Rourans, the nomadic groups that dominated the eastern Eurasian steppe in the late first millennium BC/early first millennium AD, is one of the most controversial topics in the early history of Inner Asia. As debatable is the evidence linking these two groups with the steppe nomads of early medieval Europe, i.e. the Huns and the Avars, respectively. In this paper, we address the problems of Xiongnu-Hun and Rouran-Avar connections from an interdisciplinary perspective, complementing current archaeological and historical research with a critical analysis of the available evidence from historical linguistics and population genetics. Both lines of research suggest a mixed origin of the Xiongnu population, consisting of eastern and western Eurasian substrata, and emphasize the lack of unambiguous evidence for a continuity between the Xiongnu and the European Huns. In parallel, both disciplines suggest that at least some of the European Avars were of Eastern Asian ancestry, but neither linguistic nor genetic evidence provides a sufficient support for a specific connection between the Avars and the Asian Rourans.

7.
Evol Hum Sci ; 2: e16, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-37588381

RESUMO

The 'Northern Eurasian Greenbelt' (NEG) is the northern forest zone stretching from the Japanese Archipelago to Northern Europe. The NEG has created highly productive biomes for humanity to exploit since the end of the Pleistocene. This research explores how the ecological conditions in northern Eurasia contributed to and affected human migrations and cultural trajectories by synthesizing the complimentary viewpoints of environmental archaeology, Geographic Information Science (GIS), genetics and linguistics. First, the environmental archaeology perspective raises the possibility that the NEG functioned as a vessel fostering people to develop diverse cultures and engage in extensive cross-cultural exchanges. Second, geographical analysis of genomic data on mitochondrial DNA using GIS reveals the high probability that population dynamics in the southeastern NEG promoted the peopling of the Americas at the end of the Pleistocene. Finally, a linguistic examination of environmental- and landscape-related vocabulary of the proto-Turkic language groups enables the outline of their original cultural landscape and natural conditions, demonstrating significant cultural spheres, i.e. from southern Siberia to eastern Inner Mongolia during Neolithization. All of these results combine to suggest that the ecological complex in the southern edge of the NEG in northeast Asia played a significant role in peopling across the continents during prehistory.

8.
Int J Circumpolar Health ; 79(1): 1835251, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33074067

RESUMO

Since February 2020 the COVID-19 pandemic has been unfolding in the Arctic, placing many communities at risk due to remoteness, limited healthcare options, underlying health issues and other compounding factors. Preliminary analysis of available COVID-19 data in the Arctic at the regional (subnational) level suggests that COVID-19 infections and mortality were highly variable, but generally remained below respective national levels. Based on the trends and magnitude of the pandemic through July, we classify Arctic regions into four groups: Iceland, Faroe Islands, Northern Norway, and Northern Finland with elevated early incidence rates, but where strict quarantines and other measures promptly curtailed the pandemic; Northern Sweden and Alaska, where the initial wave of infections persisted amid weak (Sweden) or variable (Alaska) quarantine measures; Northern Russia characterised by the late start and subsequent steep growth of COVID-19 cases and fatalities and multiple outbreaks; and Northern Canada and Greenland with no significant proliferation of the pandemic. Despite limitations in available data, further efforts to track and analyse the pandemic at the pan-Arctic, regional and local scales are crucial. This includes understanding of the COVID-19 patterns, mortality and morbidity, the relationships with public-health conditions, socioeconomic characteristics, policies, and experiences of the Indigenous Peoples. Data used in this paper are available at https://arctic.uni.edu/arctic-covid-19.


Assuntos
Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Alaska/epidemiologia , Regiões Árticas/epidemiologia , Betacoronavirus , COVID-19 , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/fisiopatologia , Europa (Continente)/epidemiologia , Humanos , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/fisiopatologia , Federação Russa/epidemiologia , SARS-CoV-2 , Análise Espaço-Temporal
9.
ACS Biomater Sci Eng ; 6(10): 5744-5757, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33320574

RESUMO

In this study, we prepared hydrogel scaffolds for tissue engineering by computer-assisted extrusion three-dimensional (3D) printing with photocured (λ = 445 nm) hyaluronic acid glycidyl methacrylate (HAGM). The developed product was compared with the polylactic-co-glycolic acid (PLGA) scaffolds generated by means of the original antisolvent 3D printing methodology. The cytotoxicity and cytocompatibility of the scaffolds were analyzed in vitro by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tests, flow cytometry, and scanning electron microscopy. Anti-inflammatory and proangiogenic properties of the scaffolds were evaluated in the dorsal skinfold chamber mouse model by means of intravital fluorescence microscopy, histology, and immunohistochemistry throughout an observation period of 14 days. In vitro, none of the scaffolds revealed cytotoxicity on days 1, 2, and 5 after seeding with umbilical cord-derived multipotent stromal cells, and the primary cell adhesion to the surface of HAGM scaffolds was low. In vivo, implanted HAGM scaffolds showed enhanced vascularization and host tissue ingrowth, and the inflammatory response to them was less pronounced compared with PLGA scaffolds. The results indicate excellent biocompatibility and vascularization capacity of the developed 3D printed HAGM scaffolds and position them as strong candidates for advanced tissue engineering applications.


Assuntos
Hidrogéis , Engenharia Tecidual , Adesivos , Animais , Anti-Inflamatórios , Compostos de Epóxi , Ácido Hialurônico , Metacrilatos , Camundongos , Impressão Tridimensional , Alicerces Teciduais
10.
Sensors (Basel) ; 8(8): 5055-5068, 2008 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-27873800

RESUMO

The goal of this project was to map the surface temperature of the University of Northern Iowa campus using high-resolution thermal infrared aerial imageries. A thermal camera with a spectral bandwidth of 3.0-5.0 µm was flown at the average altitude of 600 m, achieving ground resolution of 29 cm. Ground control data was used to construct the pixelto-temperature conversion model, which was later used to produce temperature maps of the entire campus and also for validation of the model. The temperature map then was used to assess the building rooftop conditions and steam line faults in the study area. Assessment of the temperature map revealed a number of building structures that may be subject to insulation improvement due to their high surface temperatures leaks. Several hot spots were also identified on the campus for steam pipelines faults. High-resolution thermal infrared imagery proved highly effective tool for precise heat anomaly detection on the campus, and it can be used by university facility services for effective future maintenance of buildings and grounds.

11.
PLoS One ; 13(12): e0206906, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30513083

RESUMO

This paper investigates the feasibility, from a user perspective, of integrating a heterogeneous information network mining (HINM) technique into SensePlace3 (SP3), a web-based geovisual analytics environment. The core contribution of this paper is a user study that determines whether an analyst with minimal background can comprehend the network data modeling metaphors employed by the resulting system, whether they can employ said metaphors to explore spatial data, and whether they can interpret the results of such spatial analysis correctly. This study confirms that all of the above is, indeed, possible, and provides empirical evidence about the importance of a hands-on tutorial and a graphical approach to explaining data modeling metaphors in the successful adoption of advanced data mining techniques. Analysis of outcomes of data exploration by the study participants also demonstrates the kinds of insights that a visual interface to HINM can enable. A second contribution is a realistic case study that demonstrates that our HINM approach (made accessible through a visual interface that provides immediate visual feedback for user queries), produces a clear and a positive difference in the outcome of spatial analysis. Although this study does not aim to validate HINM as a data modeling approach (there is considerable evidence for this in existing literature), the results of the case study suggest that HINM holds promise in the (geo)visual analytics domain as well, particularly when integrated into geovisual analytics applications. A third contribution is a user study protocol that is based on and improves upon the current methodological state of the art. This protocol includes a hands-on tutorial and a set of realistic data analysis tasks. Detailed evaluation protocols are rare in geovisual analytics (and in visual analytics more broadly), with most studies reviewed in this paper failing to provide sufficient details for study replication or comparison work.


Assuntos
Mineração de Dados/métodos , Mídias Sociais/estatística & dados numéricos , Cognição , Estudos de Viabilidade , Serviços de Informação/estatística & dados numéricos , Aprendizado de Máquina
12.
Sci Rep ; 8(1): 3663, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29483519

RESUMO

Three-dimensional (3D) rapid prototyping technology based on near-infrared light-induced polymerization of photocurable compositions containing upconversion nanomaterials has been explored. For this aim, the rationally-designed core/shell upconversion nanoparticles NaYF4:Yb3+,Tm3+/NaYF4, with the distinct ultraviolet-emitting lines and unprecedentedly high near-infrared to ultraviolet conversion efficiency of [Formula: see text] have been used. The upconverted ultraviolet photons were capable to efficiently activate photoinitiators contained in light-sensitive resins under moderate intensities of NIR excitation below 10 W cm-2 and induce generation of radicals and photopolymerization in situ. Near infrared-activated polymerization process, both at the millimeter and sub-micron scales, was investigated. Polymeric macro- and microstructures were fabricated by means of near infrared laser scanning photolithography in the volume of liquid photocurable compositions with focused laser light at 975 nm wavelength. Examination of the polymerization process in the vicinity of the nanoparticles shows strong differences in the rate of polymer shell growth on flat and edge nanoparticle sides. This phenomenon mainly defines the resolution of the demonstrated near infrared - ultraviolet 3D printing technology at the micrometer scale level.

14.
PLoS One ; 10(6): e0129202, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26086772

RESUMO

Capturing human movement patterns across political borders is difficult and this difficulty highlights the need to investigate alternative data streams. With the advent of smart phones and the ability to attach accurate coordinates to Twitter messages, users leave a geographic digital footprint of their movement when posting tweets. In this study we analyzed 10 months of geo-located tweets for Kenya and were able to capture movement of people at different temporal (daily to periodic) and spatial (local, national to international) scales. We were also able to capture both long and short distances travelled, highlighting regional connections and cross-border movement between Kenya and the surrounding countries. The findings from this study has broad implications for studying movement patterns and mapping inter/intra-region movement dynamics.


Assuntos
Emigração e Imigração , Sistemas de Informação Geográfica , Mídias Sociais , Viagem , Humanos , Quênia
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