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Efficient and fast predictive simulations of turbulent transport in the tokamak edge plasma remain a challenge and are key for preparing the operation and heat exhaust on fusion power plants. In this contribution, we present the application of a hierarchy of models to describe turbulent transport in edge fluid codes from empirical mean-field transport modelling to first principles 3D turbulent simulations. A reduced turbulent model is also presented to improve predictability of mean-field simulations. The three approaches are applied to simulate the same L-mode attached plasma on TCV. The models are compared with each other as well as with experimental measurements.

The onset of detachment in the ITER machine is analyzed in this work through the help of 2D-axisymmetric boundary plasma simulations with the SOLEDGE3X-EIRENE code, which features a numerical domain for the plasma solver extending up to the first wall. The plasma boundary is computed in scenarios from the first non-active phase of ITER, in pure H and at 20 MW. This set of simulations is used in two aspects: first, to study the plasma detachment in the divertor, and second, the plasma conditions, fluxes, and beryllium erosion at the first wall. Here, the code results are also compared to those obtained with the well-established SOLPS-ITER code, which includes a plasma numerical domain only covering the main SOL. Results show an increase in the SOL width λq with increasing density, and a detailed analysis is carried out, for the first time, on each of the different plasma-neutral interactions in the code’s physics model in EIRENE. The gross beryllium erosion rates of first wall panels are estimated from 2D simulations, with the aim of assessing their sensitivity to two parameters: the divertor density regime, and the presence of density shoulders in the far-SOL formed by enhanced perpendicular transport at this location. The erosion contributions from neutrals and ions are considered in each case, and the charge-exchange atoms fluxes and energy distributions are provided, highlighting the two atom populations (cold and charge-exchange).

This study investigates L-mode power sharing between divertor target plates in double-null (DN) magnetic configuration on the tungsten (W) Environment Steady-state Tokamak (WEST). A series of discharges scanning the distance between the separatrices at the outer mid-plane ( δ R sep ) were analyzed using Langmuir probes, embedded fiber Bragg gratings (FBGs), and calorimetry to characterize heat flux profiles and total deposited power in attached regime. Results show that DN configurations could significantly reduce the peak heat flux measured by FBGs on the lower divertor by over 70% compared to Lower Single-Null as power is more evenly distributed between upper and lower divertors. However, the heat flux is shown to be highly sensitive (peak value multiplied by 2) to millimetric variations of the δ R sep . These findings reinforce the DN configuration’s potential for mitigating peak heat loads in next step fusion devices, while highlighting the need for precise magnetic control in attached regime. Power deposition remains asymmetric in connected DN, with up to 89% of power directed to outer targets and 68% to the lower divertor, consistent with the ballooned nature of radial transport at the low-field side and downward B B × ∇ ∇ B drift effects. To quantify these effects, we develop a revised power sharing model building on Brunner’s formulation, incorporating localized sources at the inner ( S i ) and outer ( S o ) mid-plane, a vertical drift bias b , and a cooling factor κ diss . The best-fit parameters suggest that approximately 58% of the exhaust power preferentially flows downward due to vertical drifts, and that a secondary inner mid-plane source contributes up to 13% of the total power in WEST. The decay lengths obtained from the fit are in agreement with those independently measured from heat flux profiles, further validating the model.

Boron (B) powder injection is a potential alternative to glow discharge boronization as a wall conditioning method for tokamaks. This technique is currently being studied in WEST experiments, during which B powder is injected by an Impurity Powder Dropper developed by PPPL. In order to interpret and analyse experimental trends, and to help develop future experiments, a modelling workflow using a boundary plasma simulation (SOLEDGE-EIRENE) and powder ablation simulation (Dust Injection Simulator) was developed and tested. The effect of adding a B neutral source to simulated deuterium + oxygen (D + O) plasmas was compared to experimental data from the WEST C5 campaign, where B powder was injected in a dedicated experiment. While the impact of B injection on radiated power P rad measurements at the upper divertor was similar, there were significant differences in measurements of P rad , outer strike point electron temperature T e OSP and O-II line intensity at the lower divertor between experiment and simulation. This discrepancy suggests that those parameters were affected by phenomena not present in the simulations, with the most likely candidates being reduced D recycling and a reduced O sourcing from the divertor.

This paper presents the energy balance of 602 pulses from four different experimental campaigns for the WEST tokamak. Different magnetic configurations have been studied, with lower single null (LSN) and upper single null (USN) configuration with deuterium or helium plasmas. The energy balance is closed with an imbalance of about 5% of the total injected energy for most of the campaigns and for different magnetic configurations. The distribution over the whole machine is shown, with the outer first wall receiving most of the energy due to its large surface area with about 30% of the total heat load, and the divertor with 25% due to the heat loads deposited by the convected power in the scrape-off layer (SOL). Finally, the tomography inversion of the bolometry measurement allows us to disentangle the contribution of the radiated and convected power in the energy absorbed by each type of plasma-facing component. We show that in the USN configuration about 63% of the available energy in the SOL is deposited in the upper divertor (UDIV) through convected heat loads, while in LSN this value is spread over the lower divertor with 45% and the baffle and UDIV with about 10% for both.

Boron (B) powder injection is a potential alternative to glow discharge boronization as a wall conditioning method for tokamaks. This technique is currently being studied in WEST experiments, during which B powder is injected by an Impurity Powder Dropper developed by PPPL. In order to interpret and analyse experimental trends, and to help develop future experiments, a modelling workflow using a boundary plasma simulation (SOLEDGE-EIRENE) and powder ablation simulation (Dust Injection Simulator) was developed and tested. The effect of adding a B neutral source to simulated deuterium + oxygen (D + O) plasmas was compared to experimental data from the WEST C5 campaign, where B powder was injected in a dedicated experiment. While the impact of B injection on radiated power Prad measurements at the upper divertor was similar, there were significant differences in measurements of Prad, outer strike point electron temperature T^(OSP)ₑ and O-II line intensity at the lower divertor between experiment and simulation. This discrepancy suggests that those parameters were affected by phenomena not present in the simulations, with the most likely candidates being reduced D recycling and a reduced O sourcing from the divertor.

Faithful transcription initiation is critical for accurate gene expression, yet the mechanisms underlying specific transcription start site (TSS) selection in mammals remain unclear. Here, we show that the histone-fold domain protein NF-Y, a ubiquitously expressed transcription factor, controls the fidelity of transcription initiation at gene promoters in mouse embryonic stem cells. We report that NF-Y maintains the region upstream of TSSs in a nucleosome-depleted state while simultaneously protecting this accessible region against aberrant and/or ectopic transcription initiation. We find that loss of NF-Y binding in mammalian cells disrupts the promoter chromatin landscape, leading to nucleosomal encroachment over the canonical TSS. Importantly, this chromatin rearrangement is accompanied by upstream relocation of the transcription pre-initiation complex and ectopic transcription initiation. Further, this phenomenon generates aberrant extended transcripts that undergo translation, disrupting gene expression profiles. These results suggest NF-Y is a central player in TSS selection in metazoans and highlight the deleterious consequences of inaccurate transcription initiation.

Large fine mode–dominated aerosols (submicron radius) in size distributions retrieved from the Aerosol Robotic Network (AERONET) have been observed after fog or low‐altitude cloud dissipation events. These column‐integrated size distributions have been obtained at several sites in many regions of the world, typically after evaporation of low‐altitude cloud such as stratocumulus or fog. Retrievals with cloud‐processed aerosol are sometimes bimodal in the accumulation mode with the larger‐size mode often ∼0.4–0.5μm radius (volume distribution); the smaller mode, typically ∼0.12 to ∼0.20 μm, may be interstitial aerosol that were not modified by incorporation in droplets and/or aerosol that are less hygroscopic in nature. Bimodal accumulation mode size distributions have often been observed from in situ measurements of aerosols that have interacted with clouds, and AERONET size distribution retrievals made after dissipation of cloud or fog are in good agreement with particle sizes measured by in situ techniques for cloud‐processed aerosols. Aerosols of this type and large size range (in lower concentrations) may also be formed by cloud processing in partly cloudy conditions and may contribute to the “shoulder” of larger‐size particles in the accumulation mode retrievals, especially in regions where sulfate and other soluble aerosol are a significant component of the total aerosol composition. Observed trends of increasing aerosol optical depth (AOD) as fine mode radius increased suggests higher AOD in the near‐cloud environment and higher overall AOD than typically obtained from remote sensing owing to bias toward sampling at low cloud fraction. Key Points Fine mode bimodal size distributions observed after cloud/fog dissipation Cloud‐processed mode radius in good agreement with in situ measurements Fine mode large radius shoulder may indicate effects of cloud interaction

Monospecific exploitation of reindeer by Neanderthals is a common behaviour in the Upper Pleistocene of Western Europe. However, reindeer-dominated assemblages have largely been reported from regions of northern Germany and south-western France, with few examples noted in south-eastern France, where faunal assemblages yield most of the time a variety of other large ungulates such as red deer, horse and diverse bovids. Here, we present multi-strand (bio- and eco-) archaeological datasets from the site of Abri du Maras (level 4.1), situated at the mouth of the Ardèche and Rhône rivers, a new example of a reindeer-dominated Neanderthal site in south-eastern France. Dated to the beginning of the MIS 3, the zooarchaeological assemblage is dominated by reindeer (88% of the NISP, representing 16 individuals) but also includes horse, bison, giant deer ( Megaloceros giganteus ), red deer, ibex and lagomorphs. The combination of zooarchaeological, cementochronological and tooth microwear analyses evidence a single species-dominated spectrum, with catastrophic mortality and repeated autumnal deaths. This integrated approach provides an extensive picture of human subsistence behaviour, pointing to short-term hunting episodes of reindeer herds in an exceptional context of a quasi-exclusive Neanderthal accumulation. The high number of individuals and selective butchery may correspond with a cooperative and planned mass hunting strategy. The multidisciplinary approach undertaken here also incorporating paleontological, charcoal, ecological and isotopic analyses places the archaeological and zooarchaeological data within a broader regional palaeoenvironmental framework, providing valuable landscape-contextual information. The zooarchaeological data suggest a subsistence behaviour different from other Neanderthal reindeer-dominated assemblages often connected with specialised butchery or hunting sites.

Sea lice ( Copepoda, Caligidae) are the most widely distributed marine pathogens in the salmon industry in the last 30 years. Caligus rogercresseyi is the most important species affecting Chile's salmon industry. Vaccines against caligid copepods have the potential to be a cost-effective means of controlling the infestation and avoid many of the disadvantages of medicine treatments. However, research in the development of such vaccines has begun only recently and approaches used thus far have met with little or no success. In the present study, we characterized a novel gene (denoted as my32) from C. rogercresseyi which has the highest identity with the Lepeophtheirus salmonis gene akirin-2. To assess the function of the gene an RNA interference experiment was developed and a reduction in the number of ectoparasites on fish in the my32-dsRNA treated group was observed. The recombinant my32 protein was used in a vaccination-challenge trial to evaluate its ability to protect against sea lice infestations. A significant reduction in the number of parasites per fish was observed at 24 days post-challenge. These results, together with the delay observed in the development of parasites from the vaccinated group suggest that the major effect of immunization was on the second parasite generation. The results of these experiments suggest that the my32 protein may be a promising target for vaccine development to control sea lice infestations in fish.