Exhumed high‐pressure/low‐temperature (HP/LT) metamorphic rocks provide insights into deep (∼20–70 km) subduction interface dynamics. On Syros Island (Cyclades, Greece), the Cycladic Blueschist Unit ...preserves blueschist‐to‐eclogite facies oceanic‐ and continental‐affinity rocks that record the structural and thermal evolution linked to Eocene subduction. Despite decades of research, the metamorphic and deformation history (P‐T‐D) and timing of subduction and exhumation are matters of ongoing discussion. We suggest that Syros comprises three coherent tectonic slices and that each slice underwent subduction, underplating, and syn‐subduction return flow along similar P‐T trajectories, but at progressively younger times. Subduction and exhumation are distinguished by lineations and ductile fold axis orientations, and are kinematically consistent with previous studies that document top‐to‐the‐S‐SW shear (prograde‐to‐peak subduction), top‐to‐the‐NE shear (blueschist facies exhumation), and then E‐W coaxial stretching (greenschist facies exhumation). Amphibole zonations record cooling during decompression, indicating return flow above a cold slab. Multi‐mineral Rb‐Sr isochrons and compiled metamorphic geochronology show that the three slices record distinct stages of peak subduction (53–52, ∼50, and 45 Ma) that young with structural depth. Retrograde blueschist and greenschist facies fabrics span ∼50–40 and ∼43–20 Ma, respectively, and also young with structural depth. Synthesized data sets support a revised tectonic framework for Syros, involving subduction of structurally distinct coherent slices and simultaneous return flow of previously accreted tectonic slices in the subduction channel shear zone. Distributed, ductile, dominantly coaxial return flow in an Eocene‐Oligocene subduction channel proceeded at rates of ∼1.5–5 mm/yr and accommodated ∼80% of the total exhumation of this HP/LT complex.
Key Points
Syros is a tectonic stack composed of three slices constructed by subduction and underplating; peak subduction ages young with structural depth
The subduction‐to‐exhumation transition is marked by kinematic rotation and cooling during decompression
Metamorphic geochronology indicates syn‐subduction exhumation occurred continuously in an Eocene‐Oligocene subduction channel
Antibody‐mediated rejection is responsible for 30%‐50% of renal graft failures. Differentiation of B cells into antibody‐producing plasmablasts depends on the collaboration of follicular helper T ...cells (Tfh). We analyzed circulating Tfh (cTfh) in kidney recipients and studied cTfh relationship with anti‐HLA antibody production and graft outcome. cTfh were longitudinally analyzed in a prospective cohort of patients (n = 206), pre‐ and posttransplantation. Clinical data, HLA sensitization, and cTfh function were recorded. Both pretransplant and 6‐month posttransplant cTfh were able to derive IgG‐producing plasmablasts. Pretransplant cTfh was decreased in patients, especially in those who received dialysis. However, these cells were increased in patients with previous allograft or transfusions and in HLA‐sensitized recipients. After transplantation cTfh expanded, significantly more in patients who developed de novo anti‐HLA antibodies than in patients who remained unsensitized. Augmented pretransplant cTfh positively correlated with higher intensity of pretransplant anti‐HLA class I and with de novo anti‐HLA class I and anti‐HLA class II antibodies. Consistently, pretransplantation cTfh were higher in patients who experienced acute rejection (HR = 1.14 1.04‐1.25). Thus, we show a role for Tfh in anti‐HLA sensitization and rejection. Multicenter studies with additional patient cohorts are needed to validate these results. Immunosuppressive drugs targeting Tfh could be useful to improve outcomes.
Circulating follicular helper T cells are associated with anti‐HLA antibody development and acute rejection in renal transplant patients, which points these cells out as a therapeutic target to improve transplant outcome.
Wildlife monitoring can be time-consuming and expensive, but the fast-developing technologies of uncrewed aerial vehicles, sensors, and machine learning pave the way for automated monitoring. In this ...study, we trained YOLOv5 neural networks to detect points of interest, hare (Lepus europaeus), and roe deer (Capreolus capreolus) in thermal aerial footage and proposed a method to manually assess the parameter mean average precision (mAP) compared to the number of actual false positive and false negative detections in a subsample. This showed that a mAP close to 1 for a trained model does not necessarily mean perfect detection and provided a method to gain insights into the parameters affecting the trained models’ precision. Furthermore, we provided a basic, conceptual algorithm for implementing real-time object detection in uncrewed aircraft systems equipped with thermal sensors, high zoom capabilities, and a laser rangefinder. Real-time object detection is becoming an invaluable complementary tool for the monitoring of cryptic and nocturnal animals with the use of thermal sensors.
The immune response type organized against viral infection is determinant in the prognosis of some infections. This work has aimed to study Th polarization in acute COVID-19 and its possible ...association with the outcome through an observational prospective study. Fifty-eight COVID-19 patients were recruited in the Medicine Department of the hospital "12 de Octubre," 55 patients remaining after losses to follow-up. Four groups were established according to maximum degree of disease progression. T-helper cell percentages and phenotypes, analyzed by flow cytometer, and serum cytokines levels, analyzed by Luminex, were evaluated when the microbiological diagnosis (acute phase) of the disease was obtained. Our study found a significant reduction of %Th1 and %Th17 cells with higher activated %Th2 cells in the COVID-19 patients compared with reference population. A higher percent of senescent Th2 cells was found in the patients who died than in those who survived. Senescent Th2 cell percentage was an independent risk factor for death (OR: 13.88) accompanied by the numbers of total lymphocytes (OR: 0.15) with an AUC of 0.879. COVID-19 patients showed a profile of pro-inflammatory serum cytokines compared to controls, with higher levels of IL-2, IL-6, IL-15, and IP-10. IL-10 and IL-13 were also elevated in patients compared to controls. Patients who did not survive presented significantly higher levels of IL-15 than those who recovered. No significant differences were observed according to disease progression groups. The study has shown that increased levels of IL-15 and a high Th2 response are associated with a fatal outcome of the disease.
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