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Bottom currents play a major role in deep‐sea sedimentation, but their significance in the burial of organic carbon is poorly quantified at a global scale. Here we show that Holocene fluxes of organic carbon into the contourite drifts are high, with a global average of 0.09 g cm−2 Kyr−1. At individual drift sites, fluxes are commonly 1–2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones. These high fluxes of organic carbon into the contourite drifts are due to high rates of sedimentation. Over the past 50 million years, sedimentation rates at the studied contourite drift sites have overall increased, coincident with decreasing atmospheric CO2 and a cooling global climate. Our work suggests that a ramp‐up of the bottom‐current carbon pump has accelerated removal of CO2 from the atmosphere and oceanic water, thus contributing to the overall global cooling after the Eocene Thermal Maximum. Plain Language Summary Bottom currents play a major role in deep‐sea sedimentation, but their significance in the burial of organic carbon is poorly quantified at a global scale. Here we examine data from modern contourite drifts (large‐scale, alongslope‐trending bottom‐current deposits) across the globe and show modern fluxes of organic carbon into the drifts are high, with a global average of 0.09 g cm−2 Kyr−1. At individual drift sites, fluxes are commonly 1 to 2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones. These high fluxes of organic carbon into the drifts are due to high rates of sedimentation in these deepwater environments, which are driven primarily by vigorous bottom currents—in other words, by a bottom‐current pump that is highly efficient at burying organic carbon. Our work suggests that a ramp‐up of the bottom‐current carbon pump, attributable to progressive intensification of global ocean circulation over the past 50 million years, has accelerated removal of CO2 from the atmosphere and oceanic water, thus contributing to the global cooling after the Eocene Thermal Maximum. Sedimentary records of past organic carbon fluxes in contourite drifts over geologic time could well prove useful in informing predictions of future climate. Key Points Modern fluxes of organic carbon into the contourite drifts are high, with a global average of 0.09 g cm−2 Kyr−1 The fluxes into the drifts are commonly 1–2 orders of magnitude greater than rates in surrounding areas and in global depth‐similar zones Over the past 50 million years, the bottom‐current pump has accelerated removal of carbon from the oceanic water

A global Neogene cooling trend culminated ~7 million years ago with the onset of Greenland glaciation. Increased ocean-atmosphere interaction and low- to high-latitude circulation are thought to be key factors in reorganizing late Miocene global temperature and precipitation patterns, but the drivers of this reorganization have yet to be identified. Here, we present new information about the evolution of the Atlantic-Mediterranean gateway that generated Mediterranean overflow. We use sedimentary and palaeogeographic evidence to constrain the timing and dimensions of this gateway and document the initiation of a saline plume of water within the North Atlantic. Today, this saline jet entrains and transports Eastern North Atlantic water and its dissolved inorganic carbon into the interior of the ocean, contributing to the drawdown of CO 2 and the sensitivity of the ocean to atmospheric changes. We show that during the Miocene this transport emerged simultaneously with gateway restriction and propose that the resulting interaction of ocean-surface and ocean-interior carbon inventories would have greatly enhanced ocean-atmosphere exchange, preconditioning the Earth System for late Miocene cooling.

The North Pacific subtropical gyre (NPSG) plays a major role in present global ocean circulation. At times, the gyre has coursed through the South China Sea, but its role in the evolutionary development of that Sea remains uncertain. This work systematically describes a major shift in NPSG paleo-circulation evident from sedimentary features observed in seismic and bathymetric data. These data outline two contourite depositional systems—a buried one formed in the late Miocene, and a latest Miocene to present-day system. The two are divided by a prominent regional discontinuity that represents a major shift in paleo-circulation during the latest Miocene (~ 6.5 Ma). The shift coincides with the further restriction of the South China Sea with respect to the North Pacific due to the formation of the Luzon Strait as a consequence of further northwest movement of the Philippine Sea plate. Before that restriction, data indicate vigorous NPSG circulation in the South China Sea. Semi-closure, however, established a new oceanographic circulation regime in the latest Miocene. This work demonstrates the significant role of recent plate tectonics, gateway development, and marginal seas in the establishment of modern global ocean circulation.

The aim of this study was to analyse the association between physical activity and motor competence in primary school children using traditional and compositional data analysis approaches over time (time 1 and time 2). A longitudinal observational design was used to study 124 typically developed children (45.2% girls), 5–10 years old at baseline. Children's objectively measured physical activity and sedentary behaviour, actual and perceived motor competence were assessed at two time points, one year apart. Longitudinal association of movement behaviors with actual and perceived motor competence, in locomotion, ball skills and overall motor competence was explored using structural equation models, compositional analysis, and isotemporal substitution. When adjusted for sex, age, and body mass index, structural equation models and the composition consistently predicted actual and perceived motor competence at time 1 and time 2 (p < 0.01). Reallocation of 10 min from sedentary to light, or to moderate-to-vigorous physical activity, was associated with changes in actual motor competence, which was consistent from time 1 to time 2. Additionally, regarding self-perception, in time 1, isotemporal substitution of sedentary to light physical activity was the only reallocation associated with increases in perceived motor competence. In time 2, however, such positive associations were only found when reallocating time from sedentary or light to moderate-to-vigorous physical activity. Achieving adequate levels of moderate-to-vigorous physical activity, at the expense of sedentary and light physical activity, is associated with increases of actual and perceived motor competence over time.

Background Literature focusing on youth has reported limited evidence and non-conclusive associations between neighborhood walkability measures and active commuting to and from school (ACS). Moreover, there is a lack of studies evaluating both macro- and micro-scale environmental factors of the neighborhood when ACS is analyzed. Likewise, most studies on built environment attributes and ACS focus on urban areas, whereas there is a lack of studies analyzing rural residential locations. Moreover, the relationship between built environment attributes and ACS may differ in children and adolescents. Hence, this study aimed to develop walkability indexes in relation to ACS for urban and rural children and adolescents, including both macro- and micro-scale school-neighborhood factors. Methods A cross-sectional study of 4593 participants from Spain with a mean age of 12.2 (SD 3.6) years was carried out. Macro-scale environmental factors were evaluated using geographic information system data, and micro-scale factors were measured using observational procedures. Socio-demographic characteristics and ACS were assessed with a questionnaire. Several linear regression models were conducted, including all the possible combinations of six or less built environment factors in order to find the best walkability index. Results Analyses showed that intersection density, number of four-way intersections, and residential density were positively related to ACS in urban participants, but negatively in rural participants. In rural children, positive streetscape characteristics, number of regulated crossings, traffic calming features, traffic lanes, and parking street buffers were also negatively related to ACS. In urban participants, other different factors were positively related to ACS: number of regulated crossings, positive streetscape characteristics, or crossing quality. Land use mix acted as a positive predictor only in urban adolescents. Distance to the school was a negative predictor on all the walkability indexes. However, aesthetic and social characteristics were not included in any of the indexes. Conclusions Interventions focusing on improving built environments to increase ACS behavior need to have a better understanding of the walkability components that are specifically relevant to urban or rural samples.

Free cooling is a passive technique in which ventilation is used to reduce the sensible heat load when outdoor conditions are favourable. This technique is easy to apply in residential buildings, as it can be implemented either naturally or via a mechanical system. However, one should not lose the main purpose of ventilation in buildings: to ensure indoor air quality (IAQ). To assess the applicability of this technique depending on the ventilation system (natural or mechanical), an experimentally validated TRNSYS model of the detached single-family dwelling La Casa de la Tierra, coupled with a natural ventilation model in CONTAM, was applied in case studies. As a novelty, both systems are integrated into the legislative framework of minimum ventilation requirements to ensure IAQ and comfort. The results indicated that combining both systems during summer days and nights provides a much more attractive solution than relying on a single system throughout the year. Furthermore, in addition to its straightforward implementation, the proposed solution ensures IAQ, with a reduction in ventilation energy consumption of up to 46.2% in summer and allows 6.3 times more climatic cooling potential to be harnessed.

Background With recent advances in technology, patients with acute respiratory distress syndrome (ARDS) and severe acute exacerbations of chronic obstructive pulmonary disease (ae-COPD) could benefit from extracorporeal CO 2 removal (ECCO 2 R). However, current evidence in these indications is limited. A European ECCO 2 R Expert Round Table Meeting was convened to further explore the potential for this treatment approach. Methods A modified Delphi-based method was used to collate European experts’ views to better understand how ECCO 2 R therapy is applied, identify how patients are selected and how treatment decisions are made, as well as to identify any points of consensus. Results Fourteen participants were selected based on known clinical expertise in critical care and in providing respiratory support with ECCO 2 R or extracorporeal membrane oxygenation. ARDS was considered the primary indication for ECCO 2 R therapy ( n  = 7), while 3 participants considered ae-COPD the primary indication. The group agreed that the primary treatment goal of ECCO 2 R therapy in patients with ARDS was to apply ultra-protective lung ventilation via managing CO 2 levels. Driving pressure (≥ 14 cmH 2 O) followed by plateau pressure ( P plat ; ≥ 25 cmH 2 O) was considered the most important criteria for ECCO 2 R initiation. Key treatment targets for patients with ARDS undergoing ECCO 2 R included pH (> 7.30), respiratory rate (< 25 or < 20 breaths/min), driving pressure (< 14 cmH 2 O) and P plat (< 25 cmH 2 O). In ae-COPD, there was consensus that, in patients at risk of non-invasive ventilation (NIV) failure, no decrease in PaCO 2 and no decrease in respiratory rate were key criteria for initiating ECCO 2 R therapy. Key treatment targets in ae-COPD were patient comfort, pH (> 7.30–7.35), respiratory rate (< 20–25 breaths/min), decrease of PaCO 2 (by 10–20%), weaning from NIV, decrease in HCO 3 − and maintaining haemodynamic stability. Consensus was reached on weaning protocols for both indications. Anticoagulation with intravenous unfractionated heparin was the strategy preferred by the group. Conclusions Insights from this group of experienced physicians suggest that ECCO 2 R therapy may be an effective supportive treatment for adults with ARDS or ae-COPD. Further evidence from randomised clinical trials and/or high-quality prospective studies is needed to better guide decision making.

Contourite features are increasingly identified in seismic data, but the mechanisms controlling their evolution remain poorly understood. Using 2D multichannel reflection seismic and well data, this study describes large Oligocene- to middle Miocene-aged sedimentary bodies that show prominent lateral migration along the base of the Argentine slope. These form part of a contourite depositional system with four morphological elements: a plastered drift, a contourite channel, an asymmetric mounded drift, and an erosive surface. The features appear within four seismic units (SU1–SU4) bounded by discontinuities. Their sedimentary stacking patterns indicate three evolutionary stages: an onset stage (I) (~ 34–25 Ma), a growth stage (II) (~ 25–14 Ma), and (III) a burial stage (< 14 Ma). The system reveals that lateral migration of large sedimentary bodies is not only confined to shallow or littoral marine environments and demonstrates how bottom currents and secondary oceanographic processes influence contourite morphologies. Two cores of a single water mass, in this case, the Antarctic Bottom Water and its upper interface, may drive upslope migration of asymmetric mounded drifts. Seismic images also show evidence of recirculating bottom currents which have modulated the system’s evolution. Elucidation of these novel processes will enhance basin analysis and palaeoceanographic reconstructions.

Background Built environment attributes can facilitate or represent barriers to active commuting to and from school (ACS). Even though parental perceptions of the built environment and their influence on ACS in children have been extensively studied, there is very limited evidence as to whether these perceptions can vary based on the sex of children. Hence, the present study aimed to analyse the relationships between parental neighbourhood perceptions and ACS, differentiating between boys and girls. Methods This cross-sectional study was conducted in Valencia, Spain. The sample comprised 808 children and one of their parents. Parent-perceived neighbourhood environment, ACS, and socio-demographic data were self-reported through a questionnaire using validated scales. Self-organising map (SOM) analysis was used to describe the interrelationships between parental perceptions and child profiles. These analyses were carried out separately in boys and girls. Results Parents of daughters perceived their neighbourhoods as less safe from crime compared to parents of sons. The number of ACS trips was similar between boys and girls. The clustering of the SOM outcomes resulted in seven clusters, both in boys and girls. However, cluster membership had significant effects on ACS in boys, but not in girls. Globally, in the group of boys, the highest ACS levels were positively correlated with the most supportive built environments in terms of residential density, land use mix, recreational facilities, accessibility and walking facilities, traffic safety, pedestrian infrastructure, safety from crime, and aesthetics. However, some of these factors had low scores in clusters with high ACS levels (e.g., low levels of accessibility and walking facilities, and land use mix). Conclusions These findings support the idea that ACS behaviour depends on the interaction of diverse built environment factors. Our results also suggest that parental perceptions had different effects according to the sex of the child, with ACS in boys being more influenced by these perceptions. In the case of girls, it is possible that ACS interventions should emphasise generating child-friendly social environments in addition to strategies to improve the built environment. Future interventions to encourage ACS should consider these sex-specific differences and address parental concerns through improved infrastructure and safety measures.

To investigate the role of hydration to prevent contrast-induced nephropathy (CIN) in patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PPCI), we prospectively included 408 consecutive patients who were randomly assigned to receive either hydration with isotonic saline (1 ml/kg/h since the beginning of the procedure and for 24 hours after it: NS+ group) or not (NS− group). All patients received an iso-osmolar nonionic contrast medium. The primary end point was the development of CIN: ≥25% or ≥0.5 mg/dl increase in serum creatinine within 3 days after the procedure. CIN was observed in 14% of patients: 21% in the NS− group and 11% in the NS+ group (p = 0.016). CIN was significantly associated with death (15.2% vs 2.8%; p <0.0001) and need for dialysis (13.4% vs 0%; p <0.0001). In multivariate analysis, the only predictors of CIN were hydration (OR = 0.29 [0.14 to 0.66]; p = 0.003) and the hemoglobin before the procedure (OR = 0.69 [0.59 to 0.88]; p <0.0001). In conclusion, intravenous saline hydration during PPCI reduced the risk of CIN to 48%. Patients with CIN had increased mortality and need for dialysis. Given the higher incidence of CIN in emergent procedures, and its morbidity and mortality, preventive hydration should be mandatory in them unless contraindicated.