The role and future outlook for renewable energy in the Arctic zone of Russian Federation

The development of the Arctic zone of the Russian Federation (the Russian Arctic) aims to enhance the social and economic growth of the region in line with the priorities set forth by the state policy and address a range of socio-economic issues. As the Russian Arctic offers an array of hydrocarbons and renewables available in the context of the region's unbalanced infrastructural and manufacturing development and extreme climatic environment, the conditions dictate the need for an integrated use of the Arctic's energy resources. Energy security of a region is a primary contributor to its social and economic sustainability. Key energy users in the Russian Arctic include both large and local load consumers that have to operate against the background of economic and logistic difficulties related to power supply. The Russian Arctic can offer a wide range of energy resources, but individual areas are facing power shortage. These challenges are particularly relevant for the Arctic regions in Siberia and the Far East, and to a lesser extent for the Murmansk and Arkhangelsk regions as the areas are covered by the capabilities of the Unified Energy System of Russia. Energy challenges and discrepant development plans for the power and manufacturing sectors create major barriers that slow down the social and economic development of the areas. Our analysis demonstrated that the role of unconventional and renewable energy in power generation and energy mix of the Russian Arctic will remain insignificant in the short term.peer-reviewe

Дедифференцировка зрелых крысиных гепатоцитов в длительно пролиферирующие печеночные прогениторные клетки.

Objective: to obtain long-lived proliferating cells with progenitor features by dedifferentiation of mature rat hepatocytes using combinations of small molecules.Materials and Methods. Hepatocytes isolated from rat liver by perfusion were cultured in the presence of a cocktail of three small molecules – Wnt signaling pathway activator (CHIR99021), TGF-β inhibitors (A83-01) and ROCK kinase (Y27632). The morphological characteristics and growth features of the culture were assessed using fluorescence and phase-contrast microscopy during cell culture. Cell proliferative activity was analyzed using real-time time-lapse imaging. The expression of surface and intracellular markers was analyzed using flow cytometry and high-resolution fluorescence microscopy.Results. Using a cocktail of small molecules, Y-27632, A-83-01, and CHIR99021, long-lived proliferating cells that express progenitor cell markers, such as α-fetoprotein and HNF4α, were obtained from mature rat hepatocytes. The cells had hepatocyte-like morphology and formed discrete clusters of proliferating cells, forming a single cell layer during culturing. Removal of the small molecules from the medium led to expansion of fibroblast-like cells and elimination of potentially progenitor hepatocyte-like cells.Conclusion. Proliferating progenitor cells can be obtained by dedifferentiation of mature hepatocytes.Цель: получить длительно пролиферирующие клетки, обладающие признаками прогениторных, за счет дедифференцировки зрелых крысиных гепатоцитов с помощью комбинаций малых молекул.Материалы и методы. Гепатоциты, выделенные из крысиной печени путем перфузии, культивировали в присутствии набора из трех малых молекул: агониста Wnt сигнального пути (CHIR99021), ингибиторов TGF-β (A83-01) и ROCK киназы (Y27632). С помощью флуоресцентной и фазово-контрастной микроскопии в процессе культивирования клеток оценивали морфологические характеристики и особенности роста культуры. Пролиферативную активность клеток анализировали с помощью цейтраферной съемки в режиме реального времени. Экспрессию поверхностных и внутриклеточных маркеров анализировали, используя проточную цитофлуориметрию и флуоресцентную микроскопию высокого разрешения.Результаты. Используя комплекс малых молекул Y-27632, A-83-01 и CHIR99021, из зрелых крысиных гепатоцитов были получены длительно пролиферирующие клетки, которые экспрессировали маркеры прогениторных клеток, такие как α-фетопротеин и HNF4α. Клетки имели гепатоцитоподобную морфологию и формировали дискретные кластеры пролиферирующих клеток, образующих в процессе культивирования единый клеточный пласт. Удаление из среды малых молекул приводило к экспансии фибробластоподобных клеток и к элиминации потенциально прогениторных гепатоцитоподобных клеток.Заключение. Подтверждена возможность получения пролиферирующих прогениторных клеток с помощью дедифференцировки зрелых гепатоцитов

Сравнительный анализ секреторной способности островков Лангерганса, культивированных с биополимерным коллагенсодержащим гидрогелем и тканеспецифическим матриксом

Introduction. Creation of a biomedical cell product – a bioengineered pancreatic construct – is hampered by problems associated with maintaining the viability of functionally active isolated islets of Langerhans (ILs). Both biopolymer and tissue-specific scaffolds can contribute to maintaining the structure and function of isolated ILs in vitro and in vivo. The most preferred tissue-specific scaffolds for cells can be obtained via decellularized pancreas matrix scaffold (DP matrix scaffold). Objective: to conduct a comparative analysis of the secretory function of isolated ILs of rats cultured in biopolymer-based collagen-containing hydrogel (BCH) and tissue-specific DP matrix scaffold, respectively. Materials and methods. ILs from rat pancreas was isolated using classical collagenase technique with some modifications. ILs were cultured in BCH and tissue-specific scaffold under standard conditions. Tissue-specific DP matrix scaffold was obtained through decellularization of rat pancreas. The DP matrix scaffold was examined for cytotoxicity and DNA presence; it was subjected to morphological study. The secretory function of ILs was studied through enzyme-linked immunosorbent assay (ELISA). Results. The secretory function of islets cultured in BCH and DP scaffolds is significantly higher than in the monoculture of islets. The advantage of using tissue-specific DP matrix scaffolds when creating bioengineered constructs of the pancreas over BCH matrix scaffolds was identified. Conclusion. BCH and tissue-specific DP scaffolds contribute not only to preserving the viability of isolated ILs, but also to prolonging their secretory capacity for 10 days, compared with ILs monoculture.Введение. Созданию биомедицинского клеточного продукта – биоинженерной конструкции поджелудочной железы (ПЖ) – препятствуют проблемы, связанные с поддержанием жизнеспособности функционально активных изолированных островков Лангерганса (ОЛ). Сохранению структуры и функции изолированных ОЛ в условиях in vitro и in vivo могут способствовать как биополимерные, так и тканеспецифические матриксы. Наиболее предпочтительные для клеток тканеспецифические матриксы могут быть получены в результате децеллюляризации поджелудочной железы (ДПЖ-матрикс). Цель. Провести сравнительный анализ секреторной функции изолированных ОЛ крысы, культивированных в присутствии биополимерного коллагенсодержащего гидрогеля (БМКГ) и тканеспецифического ДПЖ-матрикса соответственно. Материалы и методы. ОЛ из ПЖ крысы выделяли, используя классическую коллагеназную технику с некоторыми модификациями. ОЛ культивировали в присутствии БМКГ- и тканеспецифического матрикса в стандартных условиях. Тканеспецифический ДПЖ-матрикс получали в результате децеллюляризации ПЖ крысы. ДПЖ-матрикс был исследован на цитотоксичность, присутствие ДНК и подвергнут морфологическому изучению. Секреторную функцию ОЛ исследовали методом иммуноферментного анализа (ИФА). Результаты. Было показано, что секреторная функция островков, культивированных в присутствии БМКГи ДПЖ-матрикса, значительно выше, чем в монокультуре островков. Выявлено преимущество применения тканеспецифического ДПЖ-матрикса при создании биоинженерной конструкции ПЖ по сравнению с БМКГ-матриксом. Заключение. БМКГ и тканеспецифический ДПЖ-матриксы способствуют не только сохранению жизнеспособности изолированных ОЛ, но и пролонгированию их секреторной способности в течение 10 дней, по сравнению с монокультурой ОЛ

A far-ultraviolet-driven photoevaporation flow observed in a protoplanetary disk.

Most low-mass stars form in stellar clusters that also contain massive stars, which are sources of far-ultraviolet (FUV) radiation. Theoretical models predict that this FUV radiation produces photodissociation regions (PDRs) on the surfaces of protoplanetary disks around low-mass stars, which affects planet formation within the disks. We report James Webb Space Telescope and Atacama Large Millimeter Array observations of a FUV-irradiated protoplanetary disk in the Orion Nebula. Emission lines are detected from the PDR; modeling their kinematics and excitation allowed us to constrain the physical conditions within the gas. We quantified the mass-loss rate induced by the FUV irradiation and found that it is sufficient to remove gas from the disk in less than a million years. This is rapid enough to affect giant planet formation in the disk

PDRs4All IV. An embarrassment of riches: Aromatic infrared bands in the Orion Bar

(Abridged) Mid-infrared observations of photodissociation regions (PDRs) are dominated by strong emission features called aromatic infrared bands (AIBs). The most prominent AIBs are found at 3.3, 6.2, 7.7, 8.6, and 11.2 $\mu$m. The most sensitive, highest-resolution infrared spectral imaging data ever taken of the prototypical PDR, the Orion Bar, have been captured by JWST. We provide an inventory of the AIBs found in the Orion Bar, along with mid-IR template spectra from five distinct regions in the Bar: the molecular PDR, the atomic PDR, and the HII region. We use JWST NIRSpec IFU and MIRI MRS observations of the Orion Bar from the JWST Early Release Science Program, PDRs4All (ID: 1288). We extract five template spectra to represent the morphology and environment of the Orion Bar PDR. The superb sensitivity and the spectral and spatial resolution of these JWST observations reveal many details of the AIB emission and enable an improved characterization of their detailed profile shapes and sub-components. While the spectra are dominated by the well-known AIBs at 3.3, 6.2, 7.7, 8.6, 11.2, and 12.7 $\mu$m, a wealth of weaker features and sub-components are present. We report trends in the widths and relative strengths of AIBs across the five template spectra. These trends yield valuable insight into the photochemical evolution of PAHs, such as the evolution responsible for the shift of 11.2 $\mu$m AIB emission from class B$_{11.2}$ in the molecular PDR to class A$_{11.2}$ in the PDR surface layers. This photochemical evolution is driven by the increased importance of FUV processing in the PDR surface layers, resulting in a "weeding out" of the weakest links of the PAH family in these layers. For now, these JWST observations are consistent with a model in which the underlying PAH family is composed of a few species: the so-called 'grandPAHs'.Comment: 25 pages, 10 figures, to appear in A&

PDRs4All III: JWST's NIR spectroscopic view of the Orion Bar

(Abridged) We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the HII region to the atomic PDR (crossing the ionisation front (IF)), and the subsequent transition to the molecular PDR (crossing the dissociation front (DF)). We use high-resolution near-IR integral field spectroscopic data from NIRSpec on JWST to observe the Orion Bar PDR as part of the PDRs4All JWST Early Release Science Program. The NIRSpec data reveal a forest of lines including, but not limited to, HeI, HI, and CI recombination lines, ionic lines, OI and NI fluorescence lines, Aromatic Infrared Bands (AIBs including aromatic CH, aliphatic CH, and their CD counterparts), CO2 ice, pure rotational and ro-vibrational lines from H2, and ro-vibrational lines HD, CO, and CH+, most of them detected for the first time towards a PDR. Their spatial distribution resolves the H and He ionisation structure in the Huygens region, gives insight into the geometry of the Bar, and confirms the large-scale stratification of PDRs. We observe numerous smaller scale structures whose typical size decreases with distance from Ori C and IR lines from CI, if solely arising from radiative recombination and cascade, reveal very high gas temperatures consistent with the hot irradiated surface of small-scale dense clumps deep inside the PDR. The H2 lines reveal multiple, prominent filaments which exhibit different characteristics. This leaves the impression of a "terraced" transition from the predominantly atomic surface region to the CO-rich molecular zone deeper in. This study showcases the discovery space created by JWST to further our understanding of the impact radiation from young stars has on their natal molecular cloud and proto-planetary disk, which touches on star- and planet formation as well as galaxy evolution.Comment: 52 pages, 30 figures, submitted to A&

PDRs4All II: JWST's NIR and MIR imaging view of the Orion Nebula

The JWST has captured the most detailed and sharpest infrared images ever taken of the inner region of the Orion Nebula, the nearest massive star formation region, and a prototypical highly irradiated dense photo-dissociation region (PDR). We investigate the fundamental interaction of far-ultraviolet photons with molecular clouds. The transitions across the ionization front (IF), dissociation front (DF), and the molecular cloud are studied at high-angular resolution. These transitions are relevant to understanding the effects of radiative feedback from massive stars and the dominant physical and chemical processes that lead to the IR emission that JWST will detect in many Galactic and extragalactic environments. Due to the proximity of the Orion Nebula and the unprecedented angular resolution of JWST, these data reveal that the molecular cloud borders are hyper structured at small angular scales of 0.1-1" (0.0002-0.002 pc or 40-400 au at 414 pc). A diverse set of features are observed such as ridges, waves, globules and photoevaporated protoplanetary disks. At the PDR atomic to molecular transition, several bright features are detected that are associated with the highly irradiated surroundings of the dense molecular condensations and embedded young star. Toward the Orion Bar PDR, a highly sculpted interface is detected with sharp edges and density increases near the IF and DF. This was predicted by previous modeling studies, but the fronts were unresolved in most tracers. A complex, structured, and folded DF surface was traced by the H2 lines. This dataset was used to revisit the commonly adopted 2D PDR structure of the Orion Bar. JWST provides us with a complete view of the PDR, all the way from the PDR edge to the substructured dense region, and this allowed us to determine, in detail, where the emission of the atomic and molecular lines, aromatic bands, and dust originate

Comparative analysis of the secretory capacity of islets of langerhans cultured with biopolymer-based collagen-containing hydrogel and tissue-specific matrix

Introduction. Creation of a biomedical cell product – a bioengineered pancreatic construct – is hampered by problems associated with maintaining the viability of functionally active isolated islets of Langerhans (ILs). Both biopolymer and tissue-specific scaffolds can contribute to maintaining the structure and function of isolated ILs in vitro and in vivo. The most preferred tissue-specific scaffolds for cells can be obtained via decellularized pancreas matrix scaffold (DP matrix scaffold). Objective: to conduct a comparative analysis of the secretory function of isolated ILs of rats cultured in biopolymer-based collagen-containing hydrogel (BCH) and tissue-specific DP matrix scaffold, respectively. Materials and methods. ILs from rat pancreas was isolated using classical collagenase technique with some modifications. ILs were cultured in BCH and tissue-specific scaffold under standard conditions. Tissue-specific DP matrix scaffold was obtained through decellularization of rat pancreas. The DP matrix scaffold was examined for cytotoxicity and DNA presence; it was subjected to morphological study. The secretory function of ILs was studied through enzyme-linked immunosorbent assay (ELISA). Results. The secretory function of islets cultured in BCH and DP scaffolds is significantly higher than in the monoculture of islets. The advantage of using tissue-specific DP matrix scaffolds when creating bioengineered constructs of the pancreas over BCH matrix scaffolds was identified. Conclusion. BCH and tissue-specific DP scaffolds contribute not only to preserving the viability of isolated ILs, but also to prolonging their secretory capacity for 10 days, compared with ILs monoculture