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We provide an assessment of the Infinity Two fusion pilot plant (FPP) baseline plasma physics design. Infinity Two is a four-field period, aspect ratio 
$A = 10$, quasi-isodynamic stellarator with improved confinement appealing to a max-
$J$ approach, elevated plasma density and high magnetic fields (
$ \langle B\rangle = 9$ T). Here 
$J$ denotes the second adiabatic invariant. At the envisioned operating point (
$800$ MW deuterium-tritium (DT) fusion), the configuration has robust magnetic surfaces based on magnetohydrodynamic (MHD) equilibrium calculations and is stable to both local and global MHD instabilities. The configuration has excellent confinement properties with small neoclassical transport and low bootstrap current (
$|I_{bootstrap}| \sim 2$ kA). Calculations of collisional alpha-particle confinement in a DT FPP scenario show small energy losses to the first wall (
${\lt}1.5 \,\%$) and stable energetic particle/Alfvén eigenmodes at high ion density. Low turbulent transport is produced using a combination of density profile control consistent with pellet fueling and reduced stiffness to turbulent transport via three-dimensional shaping. Transport simulations with the T3D-GX-SFINCS code suite with self-consistent turbulent and neoclassical transport predict that the DT fusion power
$P_{{fus}}=800$ MW operating point is attainable with high fusion gain (
$Q=40$) at volume-averaged electron densities 
$n_e\approx 2 \times 10^{20}$ m
$^{-3}$, below the Sudo density limit. Additional transport calculations show that an ignited (
$Q=\infty$) solution is available at slightly higher density (
$2.2 \times 10^{20}$ m
$^{-3}$) with 
$P_{{fus}}=1.5$ GW. The magnetic configuration is defined by a magnetic coil set with sufficient room for an island divertor, shielding and blanket solutions with tritium breeding ratios (TBR) above unity. An optimistic estimate for the gas-cooled solid breeder designed helium-cooled pebble bed is TBR 
$\sim 1.3$. Infinity Two satisfies the physics requirements of a stellarator fusion pilot plant.
In this work, we present a detailed assessment of fusion-born alpha-particle confinement, their wall loads and stability of Alfvén eigenmodes driven by these energetic particles in the Infinity Two Fusion Pilot Plant baseline plasma design, a four-field-period quasi-isodynamic stellarator to operate in deuterium–tritium fusion conditions. Using the Monte Carlo codes, SIMPLE, ASCOT5 and KORC-T, we study the collisionless and collisional dynamics of guiding-centre and full-orbit alpha-particles in the core plasma. We find that core energy losses to the wall are less than 4 %. Our simulations shows that peak power loads on the wall of this configuration are approximately 2.5 MW m-
$^2$ and are spatially localised, toroidally and poloidaly, in the vicinity of x-points of the magnetic island chain 
$n/m = 4/5$ outside the plasma volume. Also, an exploratory analysis using various simplified walls shows that shaping and distance of the wall from the plasma volume can help reduce peak power loads. Our stability assessment of Alfvén eigenmodes using the STELLGAP and FAR3d codes shows the absence of unstable modes driven by alpha-particles in Infinity Two due to the relatively low alpha-particle beta at the envisioned 800 MW operating scenario.
Transport characteristics and predicted confinement are shown for the Infinity Two fusion pilot plant baseline plasma physics design, a high field stellarator concept developed using modern optimization techniques. Transport predictions are made using high-fidelity nonlinear gyrokinetic turbulence simulations along with drift kinetic neoclassical simulations. A pellet-fuelled scenario is proposed that enables supporting an edge density gradient to substantially reduce ion temperature gradient turbulence. Trapped electron mode turbulence is minimized through the quasi-isodynamic configuration that has been optimized with maximum-J. A baseline operating point with deuterium–tritium fusion power of 
$P_{{fus,DT}}=800$ MW with high fusion gain 
$Q_{{fus}}=40$ is demonstrated, respecting the Sudo density limit and magnetohydrodynamic stability limits. Additional higher power operating points are also predicted, including a fully ignited (
$Q_{{fus}}=\infty$) case with 
$P_{{fus,DT}}=1.5$ GW. Pellet ablation calculations indicate it is plausible to fuel and sustain the desired density profile. Impurity transport calculations indicate that turbulent fluxes dominate neoclassical fluxes deep into the core, and it is predicted that impurity peaking will be smaller than assumed in the transport simulations. A path to access the large radiation fraction needed to satisfy exhaust requirements while sustaining core performance is also discussed.
The magnetohydrodynamic (MHD) equilibrium and stability properties of the Infinity Two fusion pilot plant baseline plasma physics design are presented. The configuration is a four-field period, aspect ratio 
$A = 10$ quasi-isodynamic stellarator optimised for excellent confinement at elevated density and high magnetic field 
$B = 9\,T$. Magnetic surfaces exist in the plasma core in vacuum and retain good equilibrium surface integrity from vacuum to an operational 
$\beta = 1.6 \,\%$, the ratio of the volume average of the plasma and magnetic pressures, corresponding to 
$800\ \textrm{MW}$ deuterium–tritium fusion operation. Neoclassical calculations show that a self-consistent bootstrap current of the order of 
${\sim} 1\ \textrm{kA}$ slightly increases the rotational transform profile by less than 0.001. The configuration has a magnetic well across its entire radius. From vacuum to the operating point, the configuration exhibits good ballooning stability characteristics, exhibits good Mercier stability across most of its minor radius and it is stable against global low-n MHD instabilities up to 
$\beta = 3.2\,\%$.
Mental Health problems and substance misuse during pregnancy constitute a serious social problem due to high maternal-fetal morbidity (Cook et al, 2017; JOCG, 39(10) ,906-915) and low detection and treatment rates (Carmona et al. Adicciones. 2022;34(4):299-308)
Our study aimed to develop and test the feasibility and acceptability of a screening and treatment clinical pathway in pregnancy, based on the combination of e-Health tools with in-person interventions and, secondly, describe the prevalence of mental illness and substance use problems in this population.
1382 pregnant women undergoing her first pregnancy visit were included in a tailored clinical pathway and sent a telematic (App) autoapplied questionnaire with an extensive battery of measures (WHO (Five) Well-Being [WHO-5],Patient Health Questionnaire [PHQ-9], General Anxiety Disorder [GAD-7], Alcohol Use Disorders Identification Test [AUDIT], Drug Abuse Screening Test [DAST], Columbia Suicide Severity Rating Scale [C-SSRS] and specifically designed questions on self-harm and psychopharmacological drugs).
Patients who did not respond to the questionnaire on their own received a counseling call.
Based on the screening results, patients were classified into five groups according to severity (Figure 1) and assigned a specific action pathway (Figure 2) that included a range of intervention intensity that goes from an individual psychiatric appointment to no intervention.
Of the 1382 women included in the clinical pathway, 565(41%) completed the evaluation questionnaires. Of these, 205 (36%) were screened as positive (Grades III,IV or V. Table 1) and 3(0.5%) were classified as needing urgent care. Of the patients offered on-line groups (100), 40% (40) were enrolled in them. Grade distribution of those screened as positivesGrade III 97 (17,2%) Grade IV 105 (18,6%) Grade V 3 (0,5%)
Concerning prevalence rates, 73 (12,9%) patients endorsed at least moderate anxiety according to GAD-7 (≥10), 65 (11,5%) endorsed at least moderate depression according to PHQ-9 (≥ 10), 17 were positive on DAST (3%) and 63 (11%) patients scored above the threshold in AUDIT-C(≥ 3) for alcohol use.
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Image 2:
High prevalence rates suggest that effective detection and treatment mechanisms should be integrated into usual care. The use of standardized clinical pathways can help with this aim, allowing better clinical management and referral to treatment, but still face challengues to increase retention. The use of e-health tools offers the opportunity to improve accessibility and therapeutic outcomes through online interventions.
None Declared
