Trends in the Incidence and Treatment of Early-Onset Pancreatic Cancer

Background: Early-onset pancreatic cancer (EOPC) is relatively uncommon. It is unclear if the incidence of EOPC is evolving and how these patients are treated. Methods: We conducted a retrospective, population-based study using SEER 2004–2016. We evaluated annual age-adjusted incidence rate (AAIR), stage at presentation, and race/ethnicity among 7802 patients plus treatment patterns in 7307 patients (excluding neuroendocrine tumors) younger than 50. Results: The AAIR was higher in males while the rate increased faster in females. The AAIR was highest in Non-Hispanic Black patients and increased for all races/ethnicities over time. The percentage of patients diagnosed with distant-stage disease decreased over time but increased for localized-stage disease. Hispanic patients made up a larger proportion of patients over time compared to other groups. For localized-stage disease, primary surgery alone was the most utilized modality of therapy. For regional-stage disease, chemotherapy with radiation was the most utilized modality from 2004–2010, whereas chemotherapy alone was the most utilized from 2011–2016. For distant-stage disease, chemotherapy alone was the most utilized and used increasingly over time. Patients with EOPC received radiation and chemotherapy at similar rates to, and underwent surgery more frequently, than patients 50–69. Conclusions: The AAIR of EOPC increased over time, faster so in females. Groups who experience a higher burden of pancreatic cancer, particularly African Americans, experienced a higher burden of EOPC. Treatment of localized and regional-stage disease did not follow standard treatment guidelines for pancreatic cancer. Our findings indicate that EOPC patients received more treatment than their older counterparts.

Analysis of the results of the performance of participants of the regional stage of the All-Russian Olympiad of schoolchildren on the subject of "Physical culture"

The introduction presents the structure of the All-Russian Olympiad for schoolchildren, its stages. Some difficulties in its organization and attitude towards it in comparison with other subject Olympiads are noted. The purpose of the article is to analyze the dynamics of the performance of participants in the regional stage of the All-Russian Olympiad for schoolchildren in the subject “Physical culture” in the Novosibirsk region from 2017 to 2021 in order to draw attention to the weaknesses in the performance and plan targeted preparation for the Olympiad, achieving results at the final stage. Materials and methods. In the period 2017-2021, on the basis of the Novosibirsk Pedagogical University, the regional stage of the All-Russian Olympiad for schoolchildren in the subject “Physical culture” was held. Observation, comparative analysis of the results of the performance of schoolchildren made it possible to reveal the presence of interest on the part of the younger generation of Russians in such a subject as “Physical culture”, as well as to reveal weaknesses in the organization and preparation for this event. Research results. Monitoring of the total number of schoolchildren, as well as the average score, which was shown in the theoretical, methodological and practical rounds among boys and girls, as expected, showed the interest and better preparation of boys in this subject. Conclusion. The materials of the article will help to plan targeted preparation for the All-Russian Olympiad in order to achieve high results in the final stage of the Olympiad.

Upper Paleozoic reef systems of the Rubezhinsky Trough (southern part of the Buzuluk Depression)

Background. The Rubezhinsky Trough has been remained one of the most poorly studied petroleum areas of the Orenburg region to date. At present, Gazprom Neft conducts systematic exploration work within the trough at five license areas of the South Orenburg Cluster. Aim. The purpose of this article is representation of preliminary new dates on a geological structure of paleozoic reef systems within the Rubezhinsky Trough. Materials and methods. The main original materials for the work are the results of the interpretation of the 3D seismic carried out at four license areas. In addition, results drilling and regional sedimentation models were involved for analysis. Results. Regional models of Upper Paleozoic reef systems of the Rubezhinsky Trough have been extensively detailed as a result of the interpretation of 3-D seismic data within the South Orenburg cluster. It was first established that isolated reefs were formed in the interval of the Ardatovian and Mullinian regional stages (Givetian Stage of Middle Devonian) of the research area. Ardatovian-mullinian isolated reefs are covered with clay deposits and represent potential lithological traps for petroleum deposits. Isolated reefs, isolated carbonate platforms and the southern margin of the vast South-Buzuluk carbonate platform with barrier reef systems have been identified for the Frasnian Stage. Isolated frasnian reefs are potential hydrocarbon traps. Barrier frasnian reefs together with increasing them early famennian ones form a series of structural hydrocarbon traps in the overlapping complexes. The significant progradation of the margin of the famennian carbonate platform towards the Pre-Caspian paleobasin is established. Famennian progradation complexes form several large clinoforms which are potentially forward looking for the search for structural-lithological petroleum traps. The barrier reef system has been confirmed for the evaporite-carbonate complex of the Okskian regional stage. Okskian reefs border the late visean epicratonic carbonate platform. Relatively large reefs of the carbonate platform barrier system were identified in the interval from Podolskian regional stage (Carboniferous) to Asselian Stage (Permian). This barrier system has progradational architectures towards the Pre-Caspian paleobasin that was formed from the end of the Middle Carboniferous to the end of the Artinskian Age of the Early Permian. Podolskian-asselian barrier buildings predefine the development of structural hydrocarbon traps of various sizes in overlapping Lower Permian deposits. Conclusions. A preliminary analysis of 3-D seismic data indicates the significant role of the paleozoic reef systems in the formation of the sedimentary complex of the Rubezhinsky trough.

Sequence composition of the Izyayu Formation (Upper Devonian–Lower Carboniferous) in the type area – the south of Tchernyshev Uplift

Research subject. The article considers the Famennian‑Tournaisian sequence of the South-Eastern part of the Tchernyshev Uplift (North Cis-Uralian). The sequence corresponds to the Izyayu Formation.Materials and methods. The article is focused on the clarification of the stratigraphy, composition and depositional environment of this formation. Research data about the Izyayu Formation in the type area (Izyayu River) were used. The stratigraphic framework of this study included data on conodonts, foraminifers and carbonate carbon isotopic shifts.Results. In the type area under study, the Izyayu Formation corresponds to the interval from the upper part of the Famennian (upper part of the Palmatolepis marginifera utahensis conodont Zone) up to the middle part of the Tournaisian (Lower crenulata conodont Zone). The formation is 100– 120 m thick. The Izyayu Formation grades to the upper part of the deep-water Syvyu Formation in the east, and to the shallow-water Kamenka Formation and the lower part of the Ydzhid Formation. The areal of the Izyayu Formation comprises the South-Eastern part of the Tchernyshev Uplift. The Formation was deposited in the environment of a gentle prograding slope of a carbonate platform.Conclusions. The Izyayu Formation in the type area is composed of thin clayey-carbonate graded cycles. It covers the stratigraphic interval from the Zelenets Regional Stage through the Tcherepet Regional Stage. This formation is easily distinguishable by lithological features in outcrops and borehole cores.

Middle–Upper Cambrian Trilobites of the Genus Nganasanella Rosova, 1963 and Their Stratigraphic Significance

—This paper presents a revision for the genus Nganasanella Rosova, 1963, first described in the stratotype of the Kulyumbean Regional Stage of the Kulyumbe River section (northwest of the Siberian Platform). This section is typical of the upper Cambrian sediments of the Kotuy–Igarka facies region, formed in a shallow marine shelf. As shown by the study, the genus comprises seven species. The species N. nganasanensis Rosova, 1963 (type species), N. tavgaensis Rosova, 1963, N. glabella (Kobayashi), 1943, N. granulosa Rosova et Makarova, 2009, and N. vernacula Rosova et Makarova, 2009 are found in the Siberian Platform. The species N. australica sp. nov. occurs in northeastern Australia. The species N. trisulcatus (Ergaliev), 1980 is widespread in southern Kazakhstan. Some species (N. granulosa and N. vernacula) are found in open marine facies sediments along with the cosmopolitan agnostid species Glyptagnostus reticulatus (Angelin), 1851, serving as a marker of the lower boundary of upper Cambrian strata in the International Chronostratigraphic Chart and the General Stratigraphic Chart of Russia. The species N. trisulcatus and N. australica are found slightly above Glyptagnostus reticulatus. Representatives of the genus Nganasanella are a link between strata of different facies containing different trilobite associations. Their stratigraphic position can serve as an argument for the correlation of the Kulyumbean Regional Stage with units containing Glyptagnostus reticulatus, i.e., the Omnian and Idamean regional stages, the lower parts of the Kutugunian Horizon and the Sakian Regional Stage, and the Paibian Stage of the International Chronostratigraphic Chart.

40Ar/39Ar geochronology of Burdigalian paleobotanical localities in the central Paratethys (south Slovakia)

The Lipovany and Mučín paleobotanical localities contain important floral associations within the tuff horizons, which were used for determination of subtropical to tropical climatic conditions during the Early Miocene. Based on the combination of results from plagioclase and biotite 40Ar/39Ar dating, the age of the tuff deposition is around 17.3Ma. For the Lipovany locality, single-grain 40Ar/39Ar convergent ages of 17.49±0.54Ma and 17.28±0.06Ma, for plagioclase and biotite were obtained, respectively. The Mučín locality only provide an imprecise convergent age of 16.5±1.4Ma due to the small size of the analyzed plagioclase crystals. The results thus allowed to include the fossil subtropical flora of the studied localities in the late Ottnangian regional stage (upper part of the Burdigalian). Additionally, these age data indicate that deposition of the overlaying Salgótarján Formation starts much later than originally thought (during Ottnangian-Karpatian boundary).

POSITION OF THE PALEOGENE STAGES BOUNDARIES IN THE SEDIMENTARY SECTION OF PLATFORM UKRAINE: CURRENT STATE, DETERMINATION CRITERIA

Data on the Global Stratotypes Sections and Points of the Paleogene Stages of the modern International Stratigraphic Scale, as well as the criteria for determining the boundaries of the Paleogene Stages in North-Western Europe are presented. The characteristics of the position of the stage boundaries in the sedimentary section of the platform Ukraine are given. In the Paleogene section of Southern Ukraine, the lower boundaries of the Ypresian and Priabonian were recognized by global correlation markers. According to the modern International Stratigraphic Scale, the position of the Lutetian / Bartonian and Rupelian / Chattian boundaries in the sedimentary sections of Southern and Northern Ukraine has been clarified in comparison with previous views. The position of most stage boundaries in the biostratigraphic (zonal) scheme of the Paleogene of Ukraine is more accurately determined. The criteria for identification for some of them in the section of the south and north of Ukraine are proposed. Most of the stage boundaries are represented by hiatus in the sedimentary cover of the platform Ukraine. Part of the boundaries of the Paleogene stages coincides with the boundaries of the regional stratigraphic units of Southern and Northern Ukraine, namely: – the Cretaceous / Paleogene boundary is at the base of the Belokamenskia and Pselian regional stages; – the Paleocene/Eocene boundary coincides with the boundary of the Merlian/Kanevian regional stages; – the Ypresian/Lutetian boundary coincides with the Kanevian/Buchakian regional stages; – the lower boundary of Priabonian is at the base of the Almian and Obukhovian regional stages; – the Eocene/Oligocene boundary passes on the limit of Almian/Planorbellian and Obukhovian/Mezhygorian regional stages; – the Rupelian/Chattian boundary is at the limit of the lower and upper regional substages of Kerleutian regional stage and at the limit of the lower and upper regional substages of the Berekian regional stage. The following stage boundaries are not coinciding with regional stage boundaries: – the Danian/Selandian boundary is within upper part of the Belokamenskian and Pselian regional stages; – the Selandian/Thanetian boundary is trassing in the lower part of the Kachian and Merlian regional stages; – the lower boundary of Ypresian is in the uppermost part of the Kachian regional stage; – the Ypresian/Lutetian boundary is within the Simferopolian regional stage; – the Lutetian/Bartonian boundary is in the lowest part of the Kumian regional stage and within the Kievian regional stage. Key words: International Stratigraphic Chart, Paleogene, stage, boundary, regional stage, Ukraine