Conodont biostratigraphy, taxonomy and palaeoecology in the Darriwilian (Middle Ordovician) of Baltoscandia - with focus on meteorite and extraterrestrial chromite-rich strata

This thesis deals with conodont biostratigraphy and palaeoecology in the Darriwilian (Middle Ordovician) of Baltoscandia, with focus on limestone strata showing traces of the ~ 470 Ma L-chondrite parent body break-up. The evidence for this cosmic event includes abundant centimeter to decimeter-sized fossil meteorites and elevated levels of sediment-dispersed extraterrestrial L-type chromite found in a stratigraphical interval corresponding to the uppermost Lenodus antivariabilis, the L. variabilis, and the Yangtzeplacognathus crassus conodont biozones, and the lower Microzarkodina hagetiana Subzone of the Lenodus (Eoplacognathus?) pseudoplanus Zone. Whereas these fossil meteorites are found only on freshly-sawed limestone-slabs at the active Thorsberg quarry on Mount Kinnekulle, southern Sweden, the occurrence of chromite has been recorded from various localities in Sweden, as well as in Russia and south-central China. A high-resolution conodont biostratigraphy over the c. 2.5 m thick, chromite-rich interval at the abandoned Hällekis quarry, Kinnekulle, was established in order to improve correlation between chromite-yielding sequences. Since the meteorite/chromite-rich interval here directly associates with a conspicuous rock sequence known as the ‘Täljsten’ interval, these strata were also investigated for palaeoecological and environmental changes. This anomalous interval has previously been suggested to represent a relative sea-level fall, but it has also been speculated that its formation could have been linked to the L-chondrite parent body break-up. Hence, the nature of the ‘Täljsten’ needed to be further explored in terms of faunal dynamics and depositional setting. The conodont fauna demonstrated continuous faunal reorganizations throughout the sampled sequence, as did additional microfaunal components. Along with observed changes in microfacies, it could be verified that the chromite-rich interval coincides with a gradually progressing regression-transgression cycle. An interesting find of tiny Panderodus conodont elements, including a serrate arcuatiform element, was made in a bed deposited just prior to the inferred maximum lowstand of the ‘Täljsten’ interval. Such serrate elements have previously been referred to as ecophenotypes of non-serrate forms, but sometimes also as distinctive species or subspecies. The Hällekis specimens, described as Panderodus serratus hallekisensis, represent one of the earliest records of the genus and hence provided clues to the primitive morphology and suprageneric relationship of Panderodus. Due to an observed tendency for overlapping morphologies and inconsistencies in identifications, the shapes of dextral Pa-elements from the zonal indices L. variabilis, Y. crassus and L. (E?) pseudoplanus were quantitatively compared using landmark-based geometric morphometrics. Linear shape of the posterior and posterio-lateral denticle rows combined was considered to best reflect the overall shape of the element-type in question, and 23 landmarks were used for the analysis; 4 fixed and 19 sliders (semi-landmarks). The analyses highlighted large-scale shape and symmetry related differences between the three species, but also revealed some overlaps. It also became clear that the three taxa display notable shape-variation of the dextral Pa element, a matter only looked into closer for L. variabilis. The Y. crassus elements included in the analysis suggest that the Baltoscandian and Chinese forms cannot be regarded as equivalents. The contingencies regarding the zonal indices naturally influence, e.g., the potential for a high-resolution correlation of chromite distribution between Kinnekulle and coeval sedimentary sequences at other localities. It was recently shown that the >1000km2 Osmussaar Breccia in north-western Estonia contains non-reworked L-type chromite, suggesting a connection to an L-chondritic impactor. An assessment of the conodont fauna of the limestones above the brecciate layers indicates that the formation of the breccia concurred with the deposition of the meteorite/chromite-yielding strata in Sweden. The limestone bed immediately superposing the breccia could be brought to the Microzakodina ozarkodella Subzone of the L. (E?) pseudoplanus Zone, i.e. only slightly higher stratigraphically than the recognized upper limit for high abundances of extraterrestrial material. This stratigraphical divergence as compared to the Swedish interval can be explained by a period of non-deposition and a resulting hiatus, a conceivable scenario considering the numerous sedimentation-gaps characterizing the early Darriwilian of north-western Estonia

A model of reconstruction for the oral apparatus of the Ordovician conodont genus Protopanderodus Lindström, 1971

Element från det ordoviciska conodontsläktet Protopanderodus Lindström, 1971 har studerats i syfte att sätta upp en modell för rekonstruktion av släktets tandapparat. Totalt har 4202 element från de fem Protopanderodus-arterna i den svenska mellanordoviciska conodontfaunan ingått i studien. Fyra av arterna, P. rectus, P. robustus, P. graeai och P. parvibasis uppvisar många gemensamma morfologiska karaktärer och utgör troligast en utvecklingslinje, medan den femte arten P. calceatus, skiljer sig åt morfologiskt. Den sistnämnda arten är således inte lika nära besläktad, och representerar eventuellt en separat utvecklingslinje. Välbevarade element från adulta individer har detaljstuderats för att identifiera och beskriva morfologiskt distinkta typer av element. Alla övriga identifierbara element (till exempel juveniler och trasiga element) har ingått i uträkningen av förhållandet mellan olika elementgrupper, i syfte att statistiskt uppskatta det lägsta antalet element i en apparat. Tre elementgrupper kunde urskiljas hos alla fem arterna; M-, S- och P-element enligt det i studien använda notationssystemet. Antalet elementtyper inom varje grupp visade sig vara annorlunda hos Protopanderodus calceatus (Ml, M2, Sa, Sb, Sc, "Sd", Pa, Pbl, Pb2) jämfört med M, Sa, Sbl, Sb2, Sc, Pa, Pb hos de övriga fyra arterna. Förhållandet mellan elementgrupperna M, S och P för P. rectus, P. robustus, P. graeai och P. parvibasis tyder på en apparat med minst 21 stycken element fördelat på 4 M (2 par), l Sa (symmetriskt), 4 Sbl (2 par), 4 Sb2 (2 par), 2 Sc (l par), 2 Pa (l par), 4 Pb (2 par). Samma minsta antal element gäller för P. calceatus men istället fördelat på 2 Ml (l par), 2 M2 (l par), l Sa (symmetriskt), 2 Sb (l par), 4 Sc (2 par), 4 "Sd" (2 par), 2 Pa (l par), 2 Pbl (l par), 2 Pb2 (l par). Huruvida P. calceatus skiljer sig tillräckligt mycket från övriga fyra arter för att föras till ett separat släkte är för närvarande osäkert. En utökad undersökning som inkluderar andra arter med morfologiska karaktärer liknande de hos P. calceatus vore önskvärd, för att i första hand jämföra apparaternas elementtyper och på så vis se om dessa arter tillhör en separat, gemensam utvecklingslinje.Elements from the Ordovician conodont genus Protopanderodus Lindström, 1971 have been investigated to provide a model of reconstruction of the oral apparatus of this genus. In total, 4202 elements from the only five species representing Protopanderodus in the Swedish Middle Ordovician conodont fauna were included in the study. Four of the species, P. rectus, P. robustus, P. graeai and P. parvibasis have similar morphological characters and are thought to belong to the same evolutionary linage. However, the fifth species, P. calceatus, is morphologically different and thus not so closely related, possibly representing a separate evolutionary linage. Well-preserved elements from adult specimens have been studied in detail for the identification of distinct element types, while all other identifiable elements (for example juveniles or somewhat broken elements) were also included in the calculation of element ratios, to statistically determine the lowest number of elements in a single apparatus. Three element groups were recognized for all five species; M-, S-, and P-elements according to the element notation system used. The number of element types in each group were quite different in P. calceatus (M1, M2, Sa, Sb, Sc, ”Sd”, Pa, Pb1, Pb2) compared to M, Sa, Sb1, Sb2, Sc, Pa, Pb in the other four species. The element ratios for the M, S and P element groups for P. rectus, P. robustus, P. graeai and P. parvibasis are indicative of an apparatus containing a minimum of 21 elements distributed as 4 M (2 pairs), 1 Sa (symmetrical), 4 Sb1 (2 pairs), 4 Sb2 (2 pairs), 2 Sc (1 pair), 2 Pa (1 pair) and 4 Pb (2 pairs). The same minimum number of elements is recognized for P. calceatus but these are instead distributed as 2 M1 (1 pair), 2 M2 (1 pair), 1 Sa (symmetrical), 2 Sb (1 pair), 4 Sc (2 pairs), 4 ”Sd” (2 pairs), 2 Pa (1 pair), 2 Pb1 (1 pair), 2 Pb2 (1 pair). At this moment it is uncertain if the dissimilarities between the apparatus of P. calceatus and the other four species suffice to refer the latter species to a new genus. Further investigations of other species, sharing the same morphological characters as P. calceatus would be desirable; the comparisons of element types in their apparatuses could show if these species belong to one single and separate evolutionary linage.Populärvetenskaplig sammanfattning: Conodonterna var en framgångsrik och diversifierad marin djurgrupp som levde från ungefär mellankambrium (~ 500 Ma) till slutet av trias (200 Ma). Från ett fåtal bevarade avtryck vet man att djuren var långsmala, endast några cm långa och hade fenor. Avtrycken är svårtolkade, men mycket tyder på att conodonterna var förhållandevis avancerade och kanske till och med de tidigaste representanterna för ryggradsdjuren, då de hade en ryggsträng, vilken är föregångare till ryggraden. Största delen av vår kunskap kommer dock från conodonternas enda mineraliserade del, deras tandapparatur, vilken var uppbyggd av ett antal kalciumfosfatiska element. Elementen är vanligt förekommande i kalksten och andra sedimentära bergarter, vilka i sin tur avslöjar under vilka förhållanden conodonterna levde. Under de ca 300 miljoner år som conodonterna levde, uppstod stora variationer mellan olika gruppers tandapparatur; från enkla former med enbart konformade element till väldigt komplexa former som innehöll uttalade elementgrupper med olika funktioner och mycket varierande form. Under de senaste årtiondena har en central del av forskningen kring conodonter handlat om att rekonstruera tandapparater, vilket hela tiden ökar kunskapen om olika conodontgruppers släktskapsförhållanden, deras evolution samt levnadssätt. Problemet är att elementen oftast hittas separata, och följaktligen är det svårt att avgöra vilka element som tillhör en art, och ännu svårare att avgöra placeringen i tandapparaten. En del yngre, mer avancerade tandapparater, har bevarats under extremt goda förhållanden och återfunnits nästan kompletta, vilket underlättar en rekonstruktion. För de flesta andra apparater arbetar man fram rekonstruktionsmodeller där man använder sig av terminologiska system för att identifiera och beskriva olika typer av element. Vanligen rekonstrueras en modell som skall gälla för ett helt släkte. Utifrån ett större antal element från släktet ifråga, kan man statistiskt räkna ut det ungefärliga antal element som tandapparaten innehöll. I min studie har jag tagit fram en rekonstruktionsmodell för det ordoviciska släktet Protopanderodus Lindström, 1971. Fem arter av släktet har ingått i studien, varav fyra av arterna säkert tillhör samma utvecklingslinje, vilket gör att deras element är relativt lika varandra. Den femte arten är inte lika nära besläktad, då elementen är utseendemässigt ganska olika de övriga arternas. Mina resultat pekar på en skillnad i tandapparatens uppbyggnad för den sistnämnda arten jämfört med de övriga fyra; antalet identifierade elementtyper var nio jämfört med sju, och dessutom var inte elementtyperna direkt utseendemässigt jämförbara. Det statistiska förhållandet mellan elementgrupperna tyder dock på en tandapparat uppbyggd av minst 21 element för alla fem arterna. Följaktligen kvarstår i framtiden att besvara huruvida den avvikande arten bör föras till ett nytt släkte, då jag funnit en del argument som talar för det. En jämförelse med andra arter med liknande utseende är därför intressant, då en jämförelse av tandapparaternas uppbyggnad kan visa huruvida dessa arter tillhör en gemensam utvecklingslinje eller inte. En utökad studie är därför nödvändig för att dra mer långtgående slutsatser

A model of reconstruction for the oral apparatus of the Ordovician conodont genus Protopanderodus Lindström, 1971

Elements of the Ordovician conodont genus Protopanderodus have been investigated in order to provide a model of reconstruction for its oral apparatus. In total, 4202 elements from the five named species representing this genus in the Swedish Middle Ordovician are included in this study; P. rectus, P. parvibasis, P. graeai, P. robustus, and P. calceatus. The well-preserved specimens were studied in detail for identification of distinct element types and calculations were made to determine element ratios and minimum number of elements in a single apparatus. Three element groups, M, S and P, were recognized for all five species and their relative ratio is indicative of apparatuses consisting of at least 21 elements. The number of element types and their distribution, however, varies between the species. The four bicostate species, P. rectus, P. parvibasis, P. graeai, and P. robustus, have similar morphological characters and are believed to belong to the same evolutionary lineage. They possessed apparatuses consisting of M, Sa, Sb1, Sb2, Sc, Pa, and Pb elements. By contrast, the multicostate species P. calceatus is morphologically different and had an apparatus consisting of M1, M2, Sa, Sb, Sc, ”Sd”, Pa, Pb1, and Pb2 elements. These differences indicate that P. calceatus is not so closely related to the other species, possibly representing a separate evolutionary lineage, and may warrant an exclusive generic assignment

Conodont dating of the Middle Ordovician breccia cap-rock limestone on Osmussaar Island, northwestern Estonia

Various mechanisms have hitherto been suggested to explain the formation of the Kundan (Middle Ordovician) Osmussaar Breccia in northwestern Estonia. Following the recent discovery of L-chondritic chromite in these peculiar, sand-penetrated strata, it seems plausible that the breccia is impact-related. Herein, the conodont faunas of three thin limestone intervals overlying the breccia at Osmussaar Island have been investigated, with the aim of establishing the age of the event in terms of the Baltoscandian conodont-based biostratigraphical scheme. Based on the presence of Microzarkodina ozarkodella, the limestone directly overlying the breccia is assigned to the M. ozarkodella Subzone of the Lenodus (Eoplacognathus?) pseudoplanus Zone. This is reinforced by means of a faunal shift between this sample interval and the subsequent one, which is directly comparable with a faunal shift in the Maekalda section, mainland Estonia. The middle, orthoceratite-yielding interval is assigned to the uppermost L. (E.?) pseudoplanus Zone (or, alternatively, the lowermost Eoplacognathus suecicus Zone), whereas the uppermost interval, an oolitic limestone, is referable to the E. foliaceus Subzone, corresponding to the lower part of the Lasnamagi Stage. These results support a connection between the Osmussaar event and the stratigraphic interval yielding abundant meteorites and/or high levels of L-type chromite in Sweden, as they both can be referred to the lower and/or middle part of the Kunda Stage. The minor difference in age between the first limestones deposited after the brecciation and the meteorite and L-chromite-yielding interval in Baltoscandia can be explained as caused by a period of non-deposition, seen as numerous hiatuses of various extent in the Kunda Stage in northwestern Estonia

Biotic dynamics and carbonate microfacies of the conspicuous Darriwilian (Middle Ordovician) 'Taljsten' interval, south-central Sweden

Enclosed in the Darriwilian (Middle Ordovician) part of the reddish 'orthoceratite limestone' of Baltoscandia is a conspicuous c. 1.5 m thick unit colloquially known as the 'Taljsten' interval. It has a wide geographical distribution in the Baltoscandian paleocontinent but is particularly well exposed in south-central Sweden. The unit is characterized by its deviant gray color and beds with a mass occurrence of cystoid echinoderms. Moreover, the recent discovery of an anomalous abundance of extraterrestrial chromite grains and micrometeorites in the 'Taljsten' and immediately adjacent strata bear witness of a time of deposition correlating to an increased influx of extraterrestrial matter to Earth. In this study we analyze the faunal dynamics, based primarily on microfossils and carbonate microfacies, across this intriguing interval. Generally known as a macrolithologically monotonous succession, the 'Taljsten' proved more heterogeneous than previously believed in terms of fossil content and preservation, as well as mineral content and composition. The general texture is wackestone/packstone, but local heterogeneities are frequent. A microfaunal reorganization occurred with a transition from a trilobite- and brachiopod-dominated community to one dominated by echinoderms, which is mirrored also macroscopically by the cystoids. The latter pelmatozoans seem to have flourished and might even have aided in the formation of the numerous hardgrounds. The increase in echinoderms is linked to a Volkhovian increase in echinoderms in eastern Baltica. In the immediate post-'Taljsten' strata there is no distinct change back to the pre-'Taljsten' biota. Conodont and ostracod faunal diversity data reveal peak values in the 'Taljsten' compared to the enclosing strata, suggesting that the paleoenvironment was more suitable for higher diversity faunas of these metazoan groups. All data collectively support a regression in the beginning of the 'Taljsten', likely followed by transgression in its upper part. (C) 2012 Elsevier B.V. All rights reserved

Cohort profile: InfCareHIV, a prospective registry-based cohort study of people with diagnosed HIV in Sweden

PURPOSE: The Swedish InfCareHIV cohort was established in 2003 to ensure equal and effective care of people living with HIV (PLHIV) and enable long-term follow-up. InfCareHIV functions equally as a decision support system as a quality registry, ensuring up-to-date data reported in real time.PARTICIPANTS: InfCareHIV includes data on >99% of all people with diagnosed HIV in Sweden and up to now 13 029 have been included in the cohort. InfCareHIV includes data on HIV-related biomarkers and antiretroviral therapies (ART) and also on demographics, patient-reported outcome measures and patient-reported experience measures.FINDINGS TO DATE: Sweden was in 2015 the first country to reach the UNAIDS (United Nations Programme on HIV/AIDS)/WHO's 90-90-90 goals. Late diagnosis of HIV infection was identified as a key problem in the Swedish HIV-epidemic, and low-level HIV viraemia while on ART associated with all-cause mortality. Increased HIV RNA load in the cerebrospinal fluid (CSF) despite suppression of the plasma viral load was found in 5% of PLHIV, a phenomenon referred to as 'CSF viral escape'. Dolutegravir-based treatment in PLHIV with pre-existing nucleoside reverse transcriptase inhibitor-mutations was non-inferior to protease inhibitor-based regimens. An increase of transmitted drug resistance was observed in the InfCareHIV cohort. Lower efficacy for protease inhibitors was not due to lower adherence to treatment. Incidence of type 2 diabetes and insulin resistance was high in the ageing HIV population. Despite ART, the risk of infection-related cancer as well as lung cancer was increased in PLHIV compared with HIV-negative. PLHIV were less likely successfully treated for cervical precancer and more likely to have human papillomavirus types not included in current HPV vaccines. Self-reported sexual satisfaction in PLHIV is improving and is higher in women than men.FUTURE PLANS: InfCareHIV provides a unique base to study and further improve long-term treatment outcomes, comorbidity management and health-related quality of life in people with HIV in Sweden

High visceral fat percentage is associated with poor outcome in endometrial cancer

Despite evidence of increased endometrial cancer (EC) risk in obese women, the impact of obesity on clinical and histological phenotype is poorly understood. This study explored abdominal fat volumes and fat distribution quantified by computed tomography (CT), in relation to tumor characteristics and outcome. 227 EC patients with preoperative abdominal CT scans were included. Total abdominal fat volume (TAV), subcutaneous abdominal fat volume (SAV) and visceral abdominal fat volume (VAV) were quantified, and visceral fat percentage calculated (VAV%=[VAV/TAV]x100). Waist circumference (WC) and liver density (LD) were measured, and body mass index (BMI) calculated. Data for estrogen, progesterone and androgen receptor (ERα/PR/AR) expression by immunohistochemistry were available for 149 tumors, and global gene expression data for 105 tumors. High BMI, TAV, SAV, VAV and WC, and low LD, were associated with low grade endometrioid tumors and PR and AR positivity (all p≤0.03). High VAV% was associated with high age (p<0.001), aneuploidy (p=0.01) and independently predicted reduced disease-specific survival (HR 1.05, 95% CI 1.00-1.11, p=0.041). Tumors from patients with low VAV% showed enrichment of gene sets related to immune activation and inflammation. In conclusion, high VAV% independently predicts reduced EC survival. Tumors arising in patients with low VAV% show enrichment of immune and inflammation related gene sets, suggesting that the global metabolic setting may be important for tumor immune response