Wave spectra of square-lattice domains in a quasi-two-dimensional binary complex plasma

Domains of square lattice have been observed in a quasi-two-dimensional binary complex plasma. The longitudinal and transverse mode of the wave spectra were measured. To compare with the experiment, Langevin dynamics simulations of a binary mixture were carried out, where the non-reciprocal interactions between different species were modeled with a point-wake Yukawa potential. A strong dependence of the wave spectra on the relative magnitude of the point-wake charge is revealed

High conservation combined with high plasticity: genomics and evolution of Borrelia bavariensis

BackgroundBorrelia bavariensis is one of the agents of Lyme Borreliosis (or Lyme disease) in Eurasia. The genome of the Borrelia burgdorferi sensu lato species complex, that includes B. bavariensis, is known to be very complex and fragmented making the assembly of whole genomes with next-generation sequencing data a challenge.ResultsWe present a genome reconstruction for 33 B. bavariensis isolates from Eurasia based on long-read (Pacific Bioscience, for three isolates) and short-read (Illumina) data. We show that the combination of both sequencing techniques allows proper genome reconstruction of all plasmids in most cases but use of a very close reference is necessary when only short-read sequencing data is available. B. bavariensis genomes combine a high degree of genetic conservation with high plasticity: all isolates share the main chromosome and five plasmids, but the repertoire of other plasmids is highly variable. In addition to plasmid losses and gains through horizontal transfer, we also observe several fusions between plasmids. Although European isolates of B. bavariensis have little diversity in genome content, there is some geographic structure to this variation. In contrast, each Asian isolate has a unique plasmid repertoire and we observe no geographically based differences between Japanese and Russian isolates. Comparing the genomes of Asian and European populations of B. bavariensis suggests that some genes which are markedly different between the two populations may be good candidates for adaptation to the tick vector, (Ixodes ricinus in Europe and I. persulcatus in Asia).ConclusionsWe present the characterization of genomes of a large sample of B. bavariensis isolates and show that their plasmid content is highly variable. This study opens the way for genomic studies seeking to understand host and vector adaptation as well as human pathogenicity in Eurasian Lyme Borreliosis agents.Peer reviewe

Stabilities of nanohydrated thymine radical cations: insights from multiphoton ionization experiments and ab initio calculations

Multi-photon ionization experiments have been carried out on thymine-water clusters in the gas phase. Metastable H2O loss from T+(H2O)n was observed at n ≥ 3 only. Ab initio quantum-chemical calculations of a large range of optimized T+(H2O)n conformers have been performed up to n = 4, enabling binding energies of water to be derived. These decrease smoothly with n, consistent with the general trend of increasing metastable H2O loss in the experimental data. The lowest-energy conformers of T+(H2O)3 and T+(H2O)4 feature intermolecular bonding via charge-dipole interactions, in contrast with the purely hydrogen-bonded neutrals. We found no evidence for a closed hydration shell at n = 4, also contrasting with studies of neutral clusters

Novel Biodegradable Polymeric Microparticles Facilitate Scarless Wound Healing by Promoting Re-epithelialization and Inhibiting Fibrosis

Despite decades of research, the goal of achieving scarless wound healing remains elusive. One of the approaches, treatment with polymeric microcarriers, was shown to promote tissue regeneration in various in vitro models of wound healing. The in vivo effects of such an approach are attributed to transferred cells with polymeric microparticles functioning merely as inert scaffolds. We aimed to establish a bioactive biopolymer carrier that would promote would healing and inhibit scar formation in the murine model of deep skin wounds. Here we characterize two candidate types of microparticles based on fibroin/gelatin or spidroin and show that both types increase re-epithelialization rate and inhibit scar formation during skin wound healing. Interestingly, the effects of these microparticles on inflammatory gene expression and cytokine production by macrophages, fibroblasts, and keratinocytes are distinct. Both types of microparticles, as well as their soluble derivatives, fibroin and spidroin, significantly reduced the expression of profibrotic factors Fgf2 and Ctgf in mouse embryonic fibroblasts. However, only fibroin/gelatin microparticles induced transient inflammatory gene expression and cytokine production leading to an influx of inflammatory Ly6C+ myeloid cells to the injection site. The ability of microparticle carriers of equal proregenerative potential to induce inflammatory response may allow their subsequent adaptation to treatment of wounds with different bioburden and fibrotic content

Ледники в горах России (Кавказ, Алтай, Камчатка) в первой четверти XXI века

The conducted studies allowed us to obtain a detailed picture of glaciation changes in the mountain regions of Russia, most provided with information about glaciers in the twentieth century. For the Caucasus glaciation, the data were obtained for the time periods 1911, 1952, 2000, 2014, 2018 and 2020; for Altai – for 1850, 1952, 2003 and 2018. For large glaciation nodes of the Central Altai – Katun, South and North Chuya Ridges additionally for 1968, 2008, and 2017. In both areas, a decrease in the area of glaciers since the beginning of the twentieth century and acceleration of the rate of reduction in the early twenty-first century have been revealed. The glaciers of the Caucasus and Altai reduced their size during this time by 46% and 48%, respectively. On average, in the twentieth century the glaciers of the Caucasus lost about 0.2% of the area per year, in the Altai – 0.15%, and in the early twentieth century 1.15 and 1.7% respectively. To study Kamchatka glaciers, we used data from the Glacier Inventory of the USSR (1950/1957) and images from different satellites in the period 2007–2019. The glaciers that were not previously registered in the Glacier Inventory of the USSR were identified. The greatest number of such glaciers is in the northern part of the Midnight Ridge, where out of 465 glaciers identified on modern satellite images, 216 were not included in the Glacier Inventory of the USSR. The area of glaciation in different regions of Kamchatka has changed extremely unevenly since the first cataloguing, which is associated with significant differences in glacier morphology. Glaciers of volcanic areas increased their size or remained stationary; here there is no tendency for glaciers to decrease due to the thick surface moraine consisting of volcanogenic material. Comparison of data from the Glacier Inventory of the USSR (as of the 1950s–70s) and the Glacier Inventory of Russia (2017–2019) shows a decrease in glaciation area from the mid-20th century to the end of the second decade of the 21st century in all mountainous regions of Russia except only the volcanic regions of Kamchatka. The area reduction ranges from 63% (Ural) to 13% (Kodar). The largest glacial systems of the Caucasus, Kamchatka and Altai have reduced their areas by 25, 22 and 39%, respectively.Проведённые в последнее время исследования позволили получить детальную картину изменений ледников в наиболее обеспеченных данными горных районах России. Для оледенения Кавказа получены данные на временные срезы 1911, 1952, 2000, 2014, 2018 и 2020 г.; для Алтая – на 1850, 1952, 2003 и 2018 г. Для крупных узлов оледенения Центрального Алтая – Катунского, Южно- и Северо-Чуйского хребтов дополнительно на 1968, 2008, 2017 г. В обоих районах выявлены устойчивое сокращение площади ледников с начала ХХ в. и ускорение темпов сокращения в начале ХХI в. Для исследования ледников Камчатки были использованы данные Каталога ледников СССР и снимки с разных спутников и за разные годы (2007–2019). Выявлено множество ледников, ранее не зарегистрированных в Каталоге ледников СССР. Площадь оледенения в разных районах Камчатки со времени первой каталогизации изменялась крайне неравномерно, что связано со значительными различиями в морфологии ледников. Ледники вулканических районов увеличили свои размеры или оставались стационарными; здесь нет тенденции к сокращению ледников из-за мощной поверхностной морены, состоящей из вулканогенного материала. Сравнение данных Каталога ледников СССР (1965–1982) и Каталога ледников России (2017–2019) показывает сокращение площади оледенения с середины ХХ в. до конца второй декады ХХI в. во всех горных районах России за исключением вулканических областей Камчатки

Новый Каталог ледников России по спутниковым данным (2016–2019 гг.)

The new Inventory of the Russian glaciers has been created at the Institute of Geography of the Russian Academy of Sciences mainly on the basis of the Sentinel 2 satellite images for 2016–2019 with the aim of assessing the current state of glacier systems and as a basis for monitoring and re-inventorying. Delineation of glacier outlines was manually made to reduce uncertainties, especially for small glaciers. The database structure is compatible with the global and national glacier archives and includes the main glacial parameters. Additionally a classification of possible catastrophic phenomena of glacial genesis was developed: dynamically unstable glaciers, glacier lakes, icebergs, etc. The data base is available online (www.glacrus.ru). At present, there are 22 glacial systems in Russia with a total area of 54,518 km2. The largest glacial systems by area are located in the Arctic archipelagos: Novaya Zemlya, Severnaya Zemlya, and Franz Josef Land. The glacial systems of the Caucasus, Kamchatka, and Altai are the largest by area in the continental part of Russia. The main group consists of 13 small glacial systems, the area of which does not exceed 100 km2. They are located in different glaciological zones: from the De Long Islands in the Arctic to the Eastern Sayan in southern Siberia. Since the compilation of the USSR glacier Inventory (1965–1982), the area of glaciers has decreased by 5,594 km2, or 9.3%. The area of polar glaciers has decreased in smaller degree than that of glaciers in mountainous regions. The results of our research confirm the trend of reducing the area of glaciers throughout the Russian territory. The magnitude and rate of changes depend on local climatic and orographic features. The exception is the glaciers of the volcanic regions of Kamchatka, the area of which has increased or remained unchanged.Создан Каталог ледников России на основе спутниковых снимков Sentinel‑2 (2016–2019 гг.) (www.glacrus.ru). Он содержит информацию о 22-х ледниковых системах общей площадью 54 518 км2. По сравнению с Каталогом ледников СССР (1965–1982 гг.) площадь ледников на территории России уменьшилась на 5594 км2, или на 9,3%. Величина и скорость изменений в разных районах сильно отличаются и зависят от местных климатических и орографических особенностей

Physics and applications of dusty plasmas: The Perspectives 2023

Dusty plasmas are electrically quasi-neutral media that, along with electrons, ions, neutral gas, radiation, and electric and/or magnetic fields, also contain solid or liquid particles with sizes ranging from a few nanometers to a few micrometers. These media can be found in many natural environments as well as in various laboratory setups and industrial applications. As a separate branch of plasma physics, the field of dusty plasma physics was born in the beginning of 1990s at the intersection of the interests of the communities investigating astrophysical and technological plasmas. An additional boost to the development of the field was given by the discovery of plasma crystals leading to a series of microgravity experiments of which the purpose was to investigate generic phenomena in condensed matter physics using strongly coupled complex (dusty) plasmas as model systems. Finally, the field has gained an increasing amount of attention due to its inevitable connection to the development of novel applications ranging from the synthesis of functional nanoparticles to nuclear fusion and from particle sensing and diagnostics to nano-contamination control. The purpose of the present perspectives paper is to identify promising new developments and research directions for the field. As such, dusty plasmas are considered in their entire variety: from classical low-pressure noble-gas dusty discharges to atmospheric pressure plasmas with aerosols and from rarefied astrophysical plasmas to dense plasmas in nuclear fusion devices. Both fundamental and application aspects are covered