Robustness of fossil fish teeth for seawater neodymium isotope reconstructions under variable redox conditions in an ancient shallow marine setting

Fossil fish teeth from pelagic open ocean settings are considered a robust archive for preserving the neodymium (Nd) isotopic composition of ancient seawater. However, using fossil fish teeth as an archive to reconstruct seawater Nd isotopic compositions in different sedimentary redox environments and in terrigenous‐dominated, shallow marine settings is less proven. To address these uncertainties, fish tooth and sediment samples from a middle Eocene section deposited proximal to the East Antarctic margin at Integrated Ocean Drilling Program Site U1356 were analyzed for major and trace element geochemistry, and Nd isotopes. Major and trace element analyses of the sediments reveal changing redox conditions throughout deposition in a shallow marine environment. However, variations in the Nd isotopic composition and rare earth element (REE) patterns of the associated fish teeth do not correspond to redox changes in the sediments. REE patterns in fish teeth at Site U1356 carry a typical mid‐REE‐enriched signature. However, a consistently positive Ce anomaly marks a deviation from a pure authigenic origin of REEs to the fish tooth. Neodymium isotopic compositions of cleaned and uncleaned fish teeth fall between modern seawater and local sediments and hence could be authigenic in nature, but could also be influenced by sedimentary fluxes. We conclude that the fossil fish tooth Nd isotope proxy is not sensitive to moderate changes in pore water oxygenation. However, combined studies on sediments, pore waters, fish teeth, and seawater are needed to fully understand processes driving the reconstructed signature from shallow marine sections in proximity to continental sources

Eficacia del diclofenaco sódico asociado con vitamina B frente al ketorolaco en el control del dolor postquirúrgico de exodoncias de terceras molares inferiores retenidas

La presente investigación comparó la eficacia analgésica del Diclofenaco Sódico asociado a vitamina B y Ketorolaco en el control del dolor postquirúrgico de terceras molares retenidas, con el fin de buscar mejores alternativas terapéuticas. Para realizar el estudio se obtuvo una muestra de 64 pacientes los cuales 31 fueron medicados con Diclofenaco Sodico asociado a vitamina B y 31 medicados con Ketorolaco, ambos vía oral y de forma aleatoria, para analizar su actividad analgésica a 6, 12 y 24 horas. Aproximadamente 20 minutos antes de la cirugía, a cada paciente se le administró 8 mg de Dexametasona vía intramuscular, con la finalidad de evitar la aparición de signos que alteren nuestro estudio y así homogenizar la muestra. Después de cada exodoncia se le administró a cada paciente 1 tableta de cada medicamento a comparar. A las 6 horas obtuvimos que el grupo de Diclofenaco Sódico asociado a vitamina B se registró como valor promedio de 1.81 en la escala del dolor. Mientras que en el grupo de Ketorolaco se registró la cifra de 2.32. A las 12 horas los pacientes administrados con Diclofenaco sódico asociado a vitamina B, registraron el valor promedio de 1.32, mientras que los pacientes administrados con Ketorolaco registraron el valor de 2.03. Pasadas las 24 horas el grupo de pacientes administrados con Diclofenaco Sodico asociado a vitamina B obtuvieron el valor promedio de 1.29 y los pacientes administrados con Ketorolaco presentaron el valor promedio de 2.00. Tomando en cuenta estos resultados, el diclofenaco sódico asociado a vitamina B obtuvo una ventaja en todos los periodos estudiados pero una ventaja estadísticamente significativa a las 12 horas posteriores a la cirugía.This study compared the analgesic efficacy of Diclofenac Sodium associated with vitamin B and ketorolac in controlling pain of retained third molars, in order to seek better therapeutic alternatives. For the study a sample of 64 patients 31 who were medicated with Diclofenac Sodium associated with vitamin B and 31 medicated with ketorolac, both orally and randomly, to analyze its analgesic activity at 6, 12 and 24 hours was obtained. Approximately 20 minutes before surgery, each patient was administered 8 mg dexamethasone intramuscularly, in order to avoid the appearance of signs that alter our study and thus homogenize the sample. After each extraction, was administered to each patient 1 tablet of each drug to be compared. At 6 hours we obtained that the group of Diclofenac Sodium associated with vitamin B average value was recorded as 1.81 on the pain scale. While in the group ketorolac figure 2.32 was recorded. At 12 hours patients administered diclofenac sodium associated with vitamin B, they recorded the average value of 1.32, while patients managed with ketorolac recorded value of 2.03. After 24 hours, the group of patients administered with Diclofenac Sodium associated with vitamin B obtained the average value of 1.29 and patients managed with ketorolac presented the average value of 2.00. Based on these results, diclofenac sodium associated with vitamin B gained an advantage in all periods studied but statistically significant at 12 hours after.Tesi

A new seismic stratigraphy for the Agulhas Plateau resembles major paleo-oceanographic changes in the Indian-Atlantic Ocean gateway since the late Miocene

The exchange of shallow and deep water masses between the Indian Ocean and the Atlantic constitutes an integral inter-ocean link in the global thermohaline circulation. In the gateway south of South Africa long-term changes in deep water flow during the Cenozoic have been initially studied using seismic reflection profiles. But the seismic stratigraphy was poorly constrained and not further resolved within the time period from the late Miocene to present. In particular, there were limited Pliocene records that could be used to investigate the influence of climatic (e.g. Antarctic ice volume) and tectonic (e.g. closure of the Central American seaway) on the deep-water variability. In 2016 the International Ocean Discovery Program (IODP) Expedition 361 (“SAFARI”) recovered complete high-resolution Plio-/Pleistocene sediment sections at six drilling locations on the southeast African margin and in the Indian-Atlantic ocean gateway. Here, we present results from Site U1475 (Agulhas Plateau), a location proximal to the entrance of North Atlantic Deep Water (NADW) to the Southern Ocean and South Indian Ocean. The site is located over a sediment drift in 2669 m water depth and comprises a complete carbonate rich (74 – 85%) stratigraphic section of the last ~7 Ma. We edited high-resolution data sets of density, velocity and natural gamma radiation measured at Site U1475 and corrected them to in-situ conditions. Cross correlations show that acoustic impedance contrasts and thus the formation of seismic reflectors are mainly due to density changes that are caused by climate-induced variations in biogenic vs. terrigenous sediment input. The calculated synthetic seismograms show an excellent correlation of drilling results with the site survey seismic field record, provide an accurate traveltime to depth conversion, and allow preliminary age assignments (± 0.3 Ma) based on the shipboard bio- and magnetostratigraphy. The most prominent reflectors are associated with compositional changes related to late Pleistocene glacial/interglacial variability, the middle Pleistocene transition, and the onset of the northern hemisphere glaciation. Furthermore, a peculiar early Pliocene interval (~ 5.3 – 4.0 Ma) bounded by two reflectors is characterized by 3-fold elevated sedimentation rates (> 10 cm/ka) and the occurrence of sediment waves. We argue that this enhanced sediment transport to the Agulhas Plateau was caused by a reorganization of the bottom current circulation pattern due to maximized inflow of NADW. Rhythmic bedding within the Pliocene sediment wave sequence likely reflects the 100-kyr orbital cycle. On the other hand, colour reflectance and natural gamma radiation show highest variability in the precession band. The very regular response of the core logging data to orbital forcing suggests that the shipboard age model can be significantly improved by cyclostratigraphy

Chronological control and centennial-scale climatic subdivisions of the Last Glacial Termination in the western Mediterranean region

The Last Glacial Termination is marked by changing environmental conditions affected by abrupt and rapid climate oscillations, such as Heinrich Stadial 1 (HS1), which is characterized by extremely low sea surface temperatures (SST) and significant changes in northern hemisphere terrestrial landscape (e.g., vegetation) and human dispersion. Previous studies show that overall cold/dry conditions occurred during HS1, but the lack of high-resolution records precludes whether climate was stable or instead characterized by instability. A high-resolution paleoclimatic record from the Padul wetland (southern Iberian Peninsula), supported by a high-resolution chronology and contrasted with other records from southern Europe and the Mediterranean region, shows 1) that the age boundaries of HS1 in this area occurred at similar to 18.0 kyr BP (median age = 17,970 cal yr BP; mean age = 18,030 +/- 330 cal yr BP) and similar to 15.2 kyr BP (median age = 15,210 cal yr BP; mean age = 15,200 +/- 420 cal yr BP) and 2) that climate during HS1 was non-stationary and centennial-scale variability in moisture is superimposed on this overall cold climatic period. In this study, we improve the pollen sampling resolution with respect to previous studies on the same Padul-15-05 sedimentary core and suggest a novel subdivision of HS1 in 7 sub-phases, including: i) 3 sub-phases (a.1-a.3) during an arid early phase (HS1a; similar to 18.4-17.2 kyr BP), ii) a relatively humid middle phase (HS1b; similar to 17.2-16.9 kyr BP), and iii) 3 sub-phases (c.1-c.3) during an arid late phase (HS1c; similar to 16.9-15.7 kyr BP). This climatic subdivision is regionally supported by SST oscillations from the Mediterranean Sea, suggesting a strong land-sea coupling. A cyclostratigraphic analysis of pollen data between 20 and 11 kyr BP indicates that the climate variability and the proposed subdivisions characterized by similar to 2000 and similar to 800-yr periodicities could be related to solar forcing controlling climate in this area. (C) 2021 Elsevier Ltd. All rights reserved.Peer reviewe

A dynamic explanation for the origin of the western Mediterranean organic-rich layers

The eastern Mediterranean sapropels are among the most intensively investigated phenomena in the paleoceanographic record, but relatively little has been written regarding the origin of the equivalent of the sapropels in the western Mediterranean, the organic-rich layers (ORLs). ORLs are recognized as sediment layers containing enhanced total organic carbon that extend throughout the deep basins of the western Mediterranean and are associated with enhanced total barium concentration and a reduced diversity (dysoxic but not anoxic) benthic foraminiferal assemblage. Consequently, it has been suggested that ORLs represent periods of enhanced productivity coupled with reduced deep ventilation, presumably related to increased continental runoff, in close analogy to the sapropels. We demonstrate that despite their superficial similarity, the timing of the deposition of the most recent ORL in the Alboran Sea is different than that of the approximately coincident sapropel, indicating that there are important differences between their modes of formation. We go on to demonstrate, through physical arguments, that a likely explanation for the origin of the Alboran ORLs lies in the response of the western Mediterranean basin to a strong reduction in surface water density and a shoaling of the interface between intermediate and deep water during the deglacial period. Furthermore, we provide evidence that deep convection had already slowed by the time of Heinrich Event 1 and explore this event as a potential agent for preconditioning deep convection collapse. Important differences between Heinrich-like and deglacial-like influences are highlighted, giving new insights into the response of the western Mediterranean system to external forcing

Mediterranean Outflow and surface water variability off southern Portugal during the early Pleistocene: A snapshot at Marine Isotope Stages 29 to 34 (1020-1135 ka)

Centennial-to-millennial scale records from IODP Site U1387, drilled during IODP Expedition 339 into the Faro Drift at 558 m water depth, now allow evaluating the climatic history of the upper core of the Mediterranean Outflow (MOW) and of the surface waters in the northern Gulf of Cadiz during the early Pleistocene. This study focuses on the period from Marine Isotope Stages (MIS) 29 to 34, i.e. the interval surrounding extreme interglacial MIS 31. Conditions in the upper MOW reflect obliquity, precession and millennial-scale variations. The benthic delta O-18 signal follows obliquity with the exception of an additional, smaller delta O-18 peak that marks the MIS 32/31 transition. Insolation maxima (precession minima) led to poor ventilation and a sluggish upper MOW core, whereas insolation minima were associated with enhanced ventilation and often also increased bottom current velocity. Millennial-scale periods of colder sea-surface temperatures (SST) were associated with short-term maxima in flow velocity and better ventilation, reminiscent of conditions known from MIS 3.A prominent contourite layer, coinciding with insolation cycle 100, was formed during MIS 31 and represents one of the few contourites developing within an interglacial period. MIS 31 surface water conditions were characterized by an extended period (1065-1091 ka) of warm SST, but SST were not much warmer than during MIS 33. Interglacial to glacial transitions experienced 2 to 3 stadial/interstadial cycles, just like their mid-to-late Pleistocene counterparts. Glacial MIS 30 and 32 recorded periods of extremely cold (<12 degrees C) SST that in their climatic impact were comparable with the Heinrich events of the mid and late Pleistocene. Glacial MIS 34, on the other hand, was a relative warm glacial period off southern Portugal. Overall, surface water and MOW conditions at Site U1387 show a strong congruence with Mediterranean climate, whereas millennial-scale variations are closely linked to North Atlantic circulation changes. (C) 2015 Elsevier B.V. All rights reserved.Fundação para a Ciência e a Tecnologia (FCT; Portugal) through MOWCADYN project [PTDC/MAR-PRO/3761/2012]; FCT [SFRH/BPD/66025/2009]; Deutsche Forschungsgemeinschaft (DFG) [BA 3809/4, RO 1113/6]; MARUM Research Center; Spanish Ministry of Science and Innovation [CTM 2011-24079]; European Union [228344-EUROFLEETS]info:eu-repo/semantics/publishedVersio

Data report: IODP Site U1387: the revised splice between Sections U1387B-18X-3 and U1387C-8R-3 (>171.6 mcd)

The Expedition 339 shipboard splice of Integrated Ocean Drilling Program (IODP) Site U1387 deeper than ~155 meters composite depth (mcd) is based on a composite of the magnetic susceptibility and natural gamma radiation data. When generating high-resolution paleoceanographic reconstructions for the Mid-Pleistocene Transition and early Pleistocene sections of Site U1387, it quickly became obvious that proxy data misfits existed at several splice transitions. Thus, a revised splice was generated for Site U1387 below Core 339-U1387B-18X based on X-ray fluorescence– derived element records (e.g., ln[Fe/Ca]) and the stable isotope records obtained for planktonic and benthic foraminifers. Corrections were needed at most of the splice transitions below Core 339-U1387A-19X, with adjustments ranging from a few centimeters to several meters. In addition, Core 339-U1387A-33X and sections of Core 36X were integrated into the revised splice to replace Core 339-U1387C-2R and sections of Core 5R, respectively. The replacement of Core 339-U1387C-2R with Core 339-U1387A33X is an option for the intended paleoceanographic research and not essential for lower resolution studies. The splice tie point table, therefore, also includes an option for a splice that retains Core 339-U1387C-2R. The extensive revision of the shipboard splice reveals that making a splice for sediment sequences rich in contourite layers and coring disturbances (biscuiting in the extended core barrel cores) can be tricky and that data misfits at splice transitions are not necessarily a data problem but could indicate a splice problem.SFRH/BPD/111433/2015info:eu-repo/semantics/publishedVersio

Percutaneous Coronary Intervention in Diabetic Patients

Cardiovascular disease (CVD) is responsible for 30% of deaths worldwide and is the leading cause of premature mortality in patients with diabetes mellitus (DM). One of the main contributors to the increased atherothrombotic risk in DM patients relates to their pro- inflammatory and prothrombotic status that involves abnormalities in endothelial and vascular smooth muscle cells, in platelet function and the coagulation cascade. The characteristics of CAD in diabetic patients is distinctive and infers an increased risk. Likewise, CAD in diabetics is characterised by being diffuse, affecting the left main stem more frequently, involving multiple vessels, and also affecting the distal coronary tree. Percutaneous coronary intervention in diabetics has been shown to have less favourable long-term clinical outcomes, compared to non-diabetics. With the advent of improved stent designs and antiplatelet drugs; the percutaneous coronary intervention (PCI) results have improved in the diabetic population. However, one of the main determinants of poorer outcomes in DM is the progression of atherosclerosis, which is more pronounced in diabetics and remains the primary cause of cardiac events at one year follow up after percutaneous revascularisation. Whilst new generation of drug-eluting stents has narrowed the gap between surgery and PCI in diabetic patients, coronary artery bypass grafting (CABG) remains the gold standard in diabetics with diffuse multivessel coronary artery disease

The Holocene Cedrus pollen record from Sierra Nevada (S Spain), a proxy for climate change in N Africa

Comprehending the effects of climate variability and disturbance on forested ecosystems is paramount to successfully managing forest environments under future climate scenarios (e.g., global warming, aridi-fication increase). Changes in fossil pollen abundance in sedimentary archives record past vegetation dynamics at regional scales, mainly related to climate changes and, in the last few millennia, to human impact. Pollen records can thus provide long databases with information on how the environment reacted to climate change before the historical record. In this study, we synthesized fossil pollen data from seven sites from the Sierra Nevada in southern Spain to investigate the response of forests in the western Mediterranean area to millennial-scale climate changes and to human impact during the Holocene. In particular, here we focused on Cedrus pollen abundances, which most-likely originated from Northern Africa and were carried to Sierra Nevada by wind. Cedrus pollen has received little attention in the Iberian Peninsula palynological records, for it occurs in low concentrations and has an African source, and thus this article explores the potential to reconstruct its past history and climate. Although Cedrus abundances are generally lower than 1% in the studied pollen samples, a comparison with North African (Moroccan) Cedrus pollen records shows similar trends at long- and short-term time-scales. Therefore, this record could be used as a proxy for changes in this forest species in North Africa. As observed in the Sierra Nevada synthetic record, the increasing trend of Cedrus pollen during the Middle and Late Holocene closely correlates with decreasing summer insolation. This would have produced overall cooler annual temperatures in Northern Africa (Middle Atlas and Rif Mountains) as well as lower summer evaporation, benefiting the growth of this cool-adapted montane tree species while increasing available moisture during the summer, which is critical for this water-demanding species. Millennial-scale variability also characterizes the Sierra Nevada Cedrus synthetic pollen record. Cedrus abundance oscillations co-vary with well-known millennial-scale climatic variability that controlled cedar abundance and altitudinal distribution in montane areas of N Africa. (C) 2020 Elsevier Ltd. All rights reserved.Peer reviewe

Millennial-scale cyclical environment and climate variability during the Holocene in the western Mediterranean region deduced from a new multi-proxy analysis from the Padul record (Sierra Nevada, Spain)

A high-resolution multi-proxy approach, integrating pollen, inorganic and organic geochemical and sedimentological analyses, has been carried out on the Holocene section of the Padul sedimentary record in the southern Iberian Peninsula reconstructing vegetation, environment and climate throughout the last ~ 11.6 cal kyr BP in the western Mediterranean. The study of the entire Holocene allows us to determine the significant climate shift that occurred during the middle-to-late Holocene transition. The highest occurrence of deciduous forest in the Padul area from ~ 9.5 to 7.6 cal kyr BP represents the Holocene humidity optimum probably due to enhanced winter precipitation during a phase of highest seasonal anomaly and maximum summer insolation. Locally, insolation maxima induced high evaporation, counterbalancing the effect of relatively high precipitation, and triggered very low water table in Padul and the deposition of peat sediments. A transitional environmental change towards more regional aridity occurred from ~ 7.6 to 4.7 cal kyr BP and then aridification enhanced in the late Holocene most likely related to decreasing summer insolation. This translated into higher water levels and a sedimentary change at ~ 4.7 cal kyr BP in the Padul wetland, probably related to reduced evaporation during summer in response to decreased in seasonality. Millennial-scale variability is superimposed on the Holocene long-term trends. The Mediterranean forest regional climate proxy studied here shows significant cold-arid events around ~ 9.6, 8.5, 7.5, 6.5 and 5.4 cal kyr BP with cyclical periodicities (~1100 and 2100 yr) during the early and middle Holocene. A change is observed in the periodicity of these cold-arid events towards ~1430 yr in the late Holocene, with forest declines around ~ 4.7–4, 2.7 and 1.3 cal kyr BP. The comparison between the Padul-15-05 data with published North Atlantic and Mediterranean paleoclimate records suggests common triggers for the observed climate variability, with the early and middle Holocene forest declines at least partially controlled by external forcing (i.e. solar activity) and the late Holocene variability associated with internal mechanisms (oceanic-atmospheric)