Search Results (120)

Rickettsia spp. are ubiquitous in nature and capable of causing diseases of varying severity. The most extensive group comprises the spotted fever group (SFG) Rickettsiae, the members of which are predominantly transmitted by ticks. The expansion of tick habitats observed in recent decades poses an increasing threat of dissemination of tick-borne infections into regions previously considered non-endemic. The aim of this study was to determine the prevalence of SFG Rickettsiae in ixodid ticks collected in Northwest Russia and to characterize the species diversity of these pathogens within the study area. Questing adult ixodid ticks (n = 4566) were collected from eight regions of Northwest Russia (Arkhangelsk, Kaliningrad, Leningrad, Novgorod, Pskov and Vologda Regions, as well as the Republic of Karelia and St. Petersburg) in 2023 to 2025 (from April to September). The species composition included Ixodes ricinus (n = 1683), Ixodes persulcatus (n = 2404), and Dermacentor reticulatus (n = 479). Genomic DNA was extracted from individual ticks and screened for SFG Rickettsiae using real-time PCR, followed by conventional PCR targeting the gltA, ompA, ompB, and sca4 (gene D) genes. Nucleotide sequences obtained for a subset of positive samples for the various genes were analyzed. The overall prevalence of SFG Rickettsiae was 12.6% (95% CI: 11.7–13.6). Circulation of the following species was detected: Rickettsia helvetica, Rickettsia conorii subsp. raoultii, Candidatus Rickettsia tarasevichiae, Rickettsia monacensis, and Rickettsia felis. The findings indicate considerable species diversity of SFG Rickettsiae in natural foci of Northwest Russia. Rickettsia monacensis was detected in ixodid ticks within the study area for the first time, and R. felis was identified in Russia for the first time. Full article

This paper presents the results of apatite fission-track (AFT) and zircon fission-track (ZFT) analysis (dating) on samples collected from the surface exposures of six Precambrian intrusions in the southeastern Fennoscandian Shield: the Avdeevo and Shala dykes, the Valaam sill, the Salmi and Wiborg batholiths, and the Kuznechenskii massif. The short mean track lengths in apatite (10.7–13.5 μm) indicate that the studied rocks resided for a prolonged period within the apatite partial annealing zone (APAZ, 60–120 °C). We suggest that the AFT ages obtained from two of the granitic intrusions—the Salmi batholith and the Kuznechenskii massif—are apparent due to α-radiation-enhanced annealing (REA), as evidenced by an inverse correlation between single-grain AFT age and effective uranium (eU) concentration, and high dispersion and a negative chi-square test. An attempt to minimize the contribution of the REA effect to the AFT data for the Salmi batholith allowed its AFT age to be estimated as 1251 ± 125 (2σ) Ma, but the same approach was unsuccessful for the Kuznechenskii massif. In contrast, the mafic intrusions show no such correlation and yield reliable AFT ages: the Avdeevo dyke, 1040 ± 104 Ma; the Shala dyke, 1145 ± 89 Ma; and the Valaam sill, 1184 ± 78 Ma. The AFT data from the Wiborg batholith can be regarded as preliminary only. The most reliable AFT ages and thermal evolution models for the studied intrusions are similar and indicate prolonged exhumation of the intrusions to the surface over more than 1 billion years, with a marked increase in cooling rates around 300 Ma, which possibly has far-field causes, such as mantle dynamics related to the initial fragmentation of Pangea. Our data, as a first approximation, suggest a similar tectono–thermal evolution for intrusions located both within the northeastern margin of the Svecofennian orogen and on the Archean Karelian craton. Full article

While the concentration of disturbed lands in northern Russia’s extractive regions is well known, the scientific value of this study lies not in confirming that geography, but in developing a replicable, data-driven framework that transforms raw spatial statistics into actionable restoration priorities. Using official 2023 data for 85 Russian regions and applying Global and Local Moran’s Indices (LISA), we demonstrate that reclamation efforts are not spatially clustered—a stark mismatch with the highly clustered pattern of disturbances. Building on this finding, we propose a two-criteria prioritization scheme: regions are selected if they belong to a statistically significant high-disturbance (HH) cluster and are not part of a high-reclamation cluster. This approach identifies not only expected industrial leaders (Krasnoyarsk Krai, Komi Republic, Tomsk and Arkhangelsk Oblasts) but also, through a complementary reclamation-coefficient analysis, uncovers territories with moderate recovery activity (Belgorod, Voronezh, Karelia) that are often overlooked when focusing solely on absolute disturbance areas. The total area of disturbed lands within the priority macro-cluster (limited to HH-cluster categories) is 81.09 thousand hectares. The study demonstrates that moving from fragmented, spatially blind interventions to a concentrated policy and investment strategy in compact zones of cumulative impact can achieve synergistic environmental, climate, and socio-economic benefits (SDGs 13, 15). By providing a transparent, spatially explicit prioritization tool, this work enables a strategic reorientation of forest-climate project planning—from reacting to local violations to proactively restoring entire clusters of accumulated environmental damage. Full article

Background: The nature and prognosis of type A intramural hematoma (TAIMH) are not well established. In this study, we evaluated the early and late outcome after surgery for this emergency condition. Methods: The ERTAAD registry included consecutive patients who underwent surgery for acute type A aortic dissection (TAAD) or TAIMH at 18 European centers for cardiac surgery. In this study, we compared the early and late outcomes of TAIMH and typical TAAD. Results: In total, 3902 consecutive patients were included in the ERTAAD registry, and 386 (9.9%) patients had TAIMH. Penn class a was present in 43.1% TAAD patients and in 34.5% TAIMH patients (p < 0.001). Among 3-month survivors, 10-year relative survival was 0.80 (95%CI 0.77–0.84) in TAAD patients and 0.76 (95%CI 0.63–0.88) in TAIMH patients. Propensity-score matching yielded 386 pairs of patients, and no significant difference was observed between the study groups in terms of early and late outcomes. In-hospital mortality rates were comparable (TAIMH 13.5% vs. TAAD 16.3%, p = 0.266). Ten-year mortality was 51.3% among TAIMH patients and 51.6% among TAAD patients (p = 0.274). TAIMH and TAAD had similar 10-year cumulative incidence rates of proximal (4.2% vs. 3.3%, p = 0.738) and distal aortic reoperations (12.6% vs. 7.6%, p = 0.779). Conclusions: This cohort study showed that the prevalence of patients with TAIMH requiring surgery is low and their risk profile is significantly different as shown by the Penn classification. The early and late outcomes of the study groups were not statistically different compared to typical TAAD when adjusted for baseline and operative variables. The relative survivals of 90-day TAIMH and TAAD survivors were low compared to the matched general population, indicating that surgically treated TAIMH demonstrated postoperative outcomes are poor and comparable to surgically treated TAAD after adjustment. Post-hoc power analysis suggested that much larger studies are needed to confirm these findings. These results are limited to TAIMH patients who underwent surgery, and this study did not address the outcome of patients who were conservatively treated. Full article

The majority of research on food webs has focused on temperate lakes, and little is known about the food web of lakes in polar regions. Subarctic lakes are particularly sensitive to climate change, which affects their stability. Therefore, the trophic structure of the food web in such lakes was considered as the object of this study. We studied a clear-water oligotrophic lake located in the subarctic region of Eurasia, specifically in northern Karelia and the White Sea coast of Russia. The study examined both open water periods (summer–autumn) and ice-covered periods (winter–spring) in this lake. Stable isotope analysis of carbon (¹³C/¹²C ratio or δ¹³C value) and nitrogen (¹⁵N/¹⁴N, δ¹⁵N) in producers and consumers was applied and revealed significant seasonal variations in the structure of the food web. The results indicate the presence of both pelagic and littoral/benthic food web compartments, with a notable contribution of autochthonous carbon derived from benthic sources. Omnivorous fish (perch, Perca fluviatilis; vendace, Coregonus albula; nine-spined sticklebacks, Pungitius pungitius) and some benthic invertebrates (mayfly, Ephemera vulgata; bivalves, Sphaerium corneum) had intermediate δ¹³C values, integrating these compartments by obtaining resources from both. Planktonic invertebrates had significantly depleted ¹³C, with the lowest δ¹³C value reaching −41.7‰, indicating an important contribution of methane-derived carbon. The study also revealed close trophic relationships between lake invertebrates and cyanobacteria, namely with planktonic Dolichospermum lemmermannii and benthic Phormidium sp. Seasonal changes in δ¹⁵N values and in trophic position have been observed among predacious omnivorous fish and crustaceans (amphipods, Gammaracanthus loricatus, and copepods, Cyclops scutifer), which are capable of a generalist feeding strategy depending on food availability. Using the example of this lake, it can be concluded that polar lake ecosystems are characterized by different seasonal intakes of allochthonous organic carbon from wetland catchment (humic compounds) and nitrogen because of nitrogen fixation in the air by cyanoprocaryotes. Alternative energy sources, such as carbon derived from methane, can also contribute to the energy balance of lake ecosystems. This study contributes to our understanding of energy flow and connectivity between producers and consumers in high-latitude lakes. Full article

Mining activities have long-term impacts on the environment even after the active stage. Historical mines developed in the 19th and 20th centuries for tin, copper, and mainly iron ore are located in the Pitkäranta area (Karelia, Russia). These objects are considered in our research as natural–anthropogenic sites of long-term water–rock interaction. Waters from flooded mines are the subject of this research. Redox conditions, pH, dissolved oxygen content, conductivity, and water temperature were determined during field work. The chemical composition of natural waters was determined by ICP-MS, ICP-AES, ion chromatography, potentiometric titration, and spectrophotometry. Our investigation showed that the mine waters are fresh and predominantly calcium–magnesium hydrocarbonate; most samples showed elevated sulfate ion contents. Circumneutral pH values and the absence of extremely high concentrations of heavy metals indicate neutral mine drainage. However the calculation of the accumulation coefficient showed the highest levels for siderophile elements relative to the corresponding data of the geochemical regional background. Moreover, zinc has the highest content in the series of heavy metal(loid)s considered. The maximum concentration of zinc was determined in the water of one of the shafts of the Lupikko mine, i.e., 5205 µg/L. The accumulation of heavy metals occurs in the process of long-term interaction of water–rock–organic matter under conductive redox conditions. Overall, the research highlighted the relevance of investigating the geochemistry of historical mines in the Pitkäranta area both from the perspective of environmental safety and the preservation of mining sites for scientific and educational purposes. Full article

Objectives: Several conditions associated with type A aortic dissection may require preoperative invasive mechanical ventilation (IMV). The current literature lacks data on this subset of patients’ prevalence and postoperative outcomes. This study aims to investigate this unexplored issue in a multicenter European registry. Methods: Data from 3735 patients included in the European Registry of Type A Aortic Dissection (ERTAAD) were the subject of this analysis. Bootstrapped Least Absolute Shrinkage and Selection Operator (LASSO) logistic regression was performed for variable selection to identify key predictors of hospital death. In the second step, a multilevel multivariable logistic regression (MMLR) was carried out, given the clustered structure of the data. Results: A total of 346 (9.3%) out of 3735 patients required preoperative IMV. Compared to the non-IMV patients, patients requiring IMV had a significantly higher rate of organ malperfusion (52% vs. 35%, p < 0.001) and a higher proportion of tears in the aortic root (p = 0.048). The in-hospital mortality rate among IMV patients was 38% vs. 15% in non-IMV patients (p < 0.001), without a difference in post-discharge survival (p = 0.84). At the MMLR, patients who required IMV had 135% higher odds of in-hospital death compared to the remaining patients. IMV yielded the second highest odds in the prediction model for in-hospital mortality (OR 2.13, CI 1.60 to 2.85, p < 0.001). Among IMV patients, the extension of surgery to the aortic arch was significantly associated with increased in-hospital mortality (p < 0.001, OR 2.98). In multivariable analysis, preoperative IMV was independently associated with increased odds of in-hospital mortality. Conclusions: The need for invasive mechanical ventilation before surgical repair for type A aortic dissection is not infrequent. In this subpopulation, the in-hospital mortality rate was twofold compared to patients who did not require IMV. The awareness of the preoperative risk profile and outcomes of this subset of patients should urge surgeons to tailor the surgical strategy more appropriately to improve the immediate postoperative results. Full article

Background: Several targeted drugs have been recently approved for the treatment of PIK3CA-mutated hormone receptor-positive (HR+)/HER2-negative (HER2−) breast cancer (BC). This study aimed at a comprehensive evaluation of the spectrum of PIK3CA alterations in Russian BC patients. Methods: The tumor material from 1872 patients with ER+/HER2− BC was tested by a combination of PCR-based methods. Results: Mutations were detected in 693/1872 (37%) cases, including 46 BC with two PIK3CA lesions. The three most common substitutions (E542K, E545K, and H1047R) were identified in 542/693 (78%) PIK3CA-mutated cases, while as many as 5.5–12% of identified mutations were not potentially detectable by common commercial kits. The study included patients of Slavic and non-Slavic ethnicities residing in regions with different climate conditions, however, these factors did not influence the distribution of PIK3CA mutations. The presence of PIK3CA variants was associated with older patient age at diagnosis (p = 0.0002), smaller tumor size (p = 0.005), lower grade (p = 0.005), Ki67 <20% (p = 0.0001) and progesterone receptor-positive status (p = 0.002) at the initial disease diagnosis, and fewer distant metastases at the time of the detection of BC spread (p = 0.0001). In a subgroup of 413 BC patients who received adjuvant tamoxifen or aromatase inhibitors, PIK3CA mutations were not associated with resistance to either type of treatment. Conclusions: The results of this study highlight the need to extend the PIK3CA testing beyond the hotspot regions of this gene. Although PIK3CA alterations contribute to the pathogenesis of HR+/HER2− BC and represent a target for several novel drugs, they are not intrinsically associated with unfavorable clinical characteristics of this subtype of cancer disease. Full article

This study revealed a significant reduction in tree growth across northern Fennoscandia following the 1600 AD eruption of Huaynaputina in Peru, the most powerful volcanic event in South America over the past two millennia. In the analysis, we utilized six tree-ring chronologies, which included the Finnish super-long chronology (5634 BC–2004 AD), the Kola Peninsula chronology (1445–2004 AD), and historical chronologies derived from old wooden churches in Finnish Lapland and Karelia, Russia. Using a superposed epoch analysis across these chronologies revealed a significant 24% (p < 0.01) decline in tree-ring growth in 1601 compared to the previous six years. The northernmost records, the Finnish super-long chronology (72%, p < 0.001) and the Sodankylä Old Church chronology (67%, p < 0.001), showed the most pronounced decreases. Statistical analysis confirmed significant (p < 0.05) similarities in tree-ring responses across all chronologies from 1601 to 1608. These findings underscore the reliability of using the 1600 Huaynaputina eruption as a chronological marker for dating historic wooden churches in northern Fennoscandia that were likely built between the late 17th and early 18th centuries. Additionally, analyzing church wood may provide insights into past climate patterns and environmental conditions linked to the eruption. Full article

This study was performed on the territory of Northern Europe in the Middle taiga subzone of Karelia. The work was conducted at two test sites (Site I, Site II) located in a pine forest in the coastal area of Lake Segozero. In these territories, areas under juniper (UCB) and under lingonberry-blueberry plant microgroups (CB) were isolated. This article presents the results of the effect of juniper on the properties of the upper soil horizon, forest litter (O), and mineral podzolic horizon (E (UCB)). The forest floor (O), and the mineral podzolic horizon (E) of soils located under the lingonberry-blueberry plant microgroup (CB) were selected as controls. The volume weight; acidity; content of total C, total N, total K, and total P had differences in different horizons (O, E) of the soils at the studied sites (Site I, Site II; CB, UCB). The results showed a tendency for C and N reserves to increase in the upper soil horizon under juniper. K and P reserves in this soil horizon tended to decrease. An increase in catalase activity was found in soils under juniper (Site I, II—UCB), which indicates a change in redox conditions. An increase in the rate of cellulose decomposition was noted in UCB sites compared with CB, which is consistent with the results of other studies. Mathematical and statistical analysis confirmed the formation of vegetative microgroups (CB and UCB) in cranberry pine (Site I, Site II) and also allowed us to identify conjugate pairs of chemical parameters (nitrogen reserves, C, catalase activity, and cellulose-destroying ability of soils) that differ in these sites. Full article

Lake ice has a major impact on the functioning of lake ecosystems, the thermal and gas regimes of lakes, habitat conditions, socio-economic aspects of human life, local climate, etc. The multifaceted influence of lake ice makes it important to study its changes associated with global warming, including lake ice phenology, ice thickness, and the snow–ice fraction. This article presents a study of lake ice changes in different regions of Eurasia: the Arctic (Lake Imandra in the Murmansk region and Lake Kilpisjärvi in Finland), the temperate zone (six small and medium lakes in Karelia, Mozhaysk Reservoir in the Moscow region, and Lake Pääjärvi in Finland), the arid zone (Lake Ulansuhai in China), and the highlands (lakes Arpi and Sevan in Armenia). In the study regions, a statistically significant increase in winter air temperature has been recorded over the past few decades. The number of days with thaw (air temperature above 0 °C) has increased, while the number of days with severe frost (air temperature below −10 °C and −20 °C) has decreased. The share of liquid or mixed precipitation in winter increases most rapidly in the temperate zone. For two Finnish lakes, lakes Vendyurskoe and Vedlozero in Karelia, and Mozhaysk Reservoir, a decrease in the duration of the ice period was revealed, with later ice-on and earlier ice-off. The most dramatic change occurred in the large high-mountain Lake Sevan, where the water area has no longer been completely covered with ice every winter. In contrast, the small high-mountain Lake Arpi showed no significant changes in ice phenology over a 50-year period. Changes in the ice composition with an increase in the proportion of white ice and a decrease in the proportion of black ice have occurred in some lakes. In the temperate lakes Pääjärvi and Vendyurskoe, inverse dependences of the thickness of black ice on the number of days with thaw and frost in December–March for the first lake and on the amount of precipitation in the first month of ice for the second were observed. In the arid study region of China, due to the very little winter precipitation (usually less than 10 mm) only black ice occurs, and significant interannual variability in its thickness has been identified. Full article

We proposed and investigated a refinement of technology for obtaining Mg-doped LiNbO₃ (LN) crystals by co-doping it with B. LN:Mg (5.0 mol%) is now the most widely used material based on bulk lithium niobate. It is suitable for light modulation and transformation. We found that non-metal boron decreases threshold concentrations of the target dopant in many ways. In addition, we earlier determined that the method of boron introduction into the LN charge strongly affects the LN:B crystal structure. So we investigated the point structural defects of two series of LN:Mg:B crystals obtained by different doping methods, in which the stage of dopant introduction was different. We investigated the features of boron cation localization in LN:Mg:B single crystals. We conducted the study using XRD (X-ray diffraction) analysis. We have confirmed that the homogeneous doping method introduces an additional defect (Mg_V) into the structure of LN:Mg:B single crystals. Vacancies in niobium positions (V_Nb) are formed as a compensator for the excess positive charge of point structural defects. According to model calculations, boron is localized in most cases in the tetrahedron face common with the vacant niobium octahedron from the first layer (V_Nb^IO₆). The energy of the Coulomb interaction is minimal in the LN:Mg:B crystal (2.57 mol% MgO and 0.42 × 10⁻⁴ wt% B in the crystal); it was obtained using the solid-phase doping technology. The solid-phase doping technology is better suited for obtaining boron-containing crystals with properties characteristic of double-doped crystals (LN:Mg:B). Full article

Finnish North Karelia is a region with a rich cultural history of ethnomedicinal plant use, shaped by centuries of interactions among various ethnic groups. This study identified both similarities and divergences between local Finns, Karelians war refugees, and individuals of mixed origin compared to historical records. Based on 67 semi-structured interviews, we documented the use of 43 medicinal plant taxa from 25 families, of which 31 remain in use. Notably, the number of medicinal plants continuously used in North Karelia is considerably lower than in other parts of Europe, with less than 25% of historically utilised species still in practice, which reflects the fragile state of this knowledge. Factors such as forced relocation, the loss of traditional lands, and the need to adapt to new environments might have contributed to this decline. Another influencing factor is official healthcare attitudes, which have prompted Finnish residents to shift from traditional herbal remedies to modern medical practices. Understanding the circulation of ethnomedicinal knowledge and its transformation over time is essential for identifying pathways to revitalise these practices within the framework of modern healthcare systems and cultural revitalisation efforts. Full article

This study explores how higher education institutions (HEIs) can foster the relevance of education for sustainable development (ESD) and strategic human resource development for a holistic sustainability transformation. Sharing a case example, it discusses how sustainable and responsible research, development and innovation (RDI) competences can be recognised, described and acknowledged to support the contextualised application of ESD and human resource development in one HEI of the INVEST university alliance and its stakeholders. It compares education professionals’ and stakeholders’ views on current and future competence needs and investigates inter-organisational competence development practices. The methodology encompasses a qualitative and interpretive case study based on focus group interviews. The results on the current sustainable competences indicated that HEI and stakeholder respondents identified disciplinary competences as the most important competence cluster followed by systems-thinking, strategies-thinking and integration competences. Although HEIs and stakeholders jointly regard disciplinary competences as most critical for the future, they have considerably different perspectives on the megatrends influencing these needs and the overall spectrum of the required competences. This study provides methodological means for contextualising sustainability competences and enhancing stakeholder-informed competence development. The results may serve as a point of reference for aligning higher education curricula and human resource development with ESD for more sustainable higher education. Full article