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Quenching with polymer solutions for steel heat treatment offers adjustable performance and improved ecological impact compared to conventional water or oil quenching. The submersion cooling operation poses challenges due to the intense vapor/polymer film collapse on the component surface, potentially destabilizing batch components. Therefore, controlled recirculation is critical to preventing tank and specimen damage during cooling and ensuring effective steel hardening. However, flow structure analysis is often overlooked and disregarded in industrial tank design. Thus, this study evaluates the tank geometries of two partner industries to determine if they provide the necessary homogeneous flow for optimal quenching. The analysis combines experimental velocity measurements with a numerical model, with the identification of different flow intensity regions being the main outcome of this work. The results suggest that geometric modifications could improve flow recirculation, enhancing quenching performance.

In addition to various advantages over oil quenching, quenching in aqueous polymer solutions can also have disadvantages. Under certain conditions, “explosive” phenomena can occur when quenching steel components in such solutions, leading to pressure waves and vibrations in the quenching tank, which can even destroy the weld seams of the tank in the long term. After these processes were analyzed in the past when quenching cylindrical shafts, the processes occurring with horizontally charged disks have now been investigated. The main difference between these two geometries lies in the size of the lower disk end face, which significantly impedes the outflow of evaporated portions of the aqueous polymer solutions and thus has a pronounced influence on the cooling behavior of disk-shaped components. The investigations to be presented here were carried out in a laboratory quenching tank. The type and concentration of the polymer, the flow type and the diameter of the inner bore of the disks were varied. Temperature and conductivity were measured and audio and video recordings were made to characterize the resulting cooling processes. Selected quenching variants are presented in detail in the article. Furthermore, key figures for characterizing the various cooling variants are compared and discussed.

AbstractIndividuals identified as Aricidea assimilisTebble, 1959 were collected from ten localities across the Mediterranean Sea from 0.5 to 225 m depth in order to have a wide coverage of the species habitats and geographic range and to assess the effects of environmental factors and biogeographical barriers on molecular and morphological diversity. Two mitochondrial and one nuclear markers were used to reconstruct phylogenetic relationships and test the occurrence of cryptic species. We observed two highly divergent lineages, one including all individuals from shallow, sandy environments (<10 m depth) and the other with the individuals from deeper muddy bottoms (30–225 m depth). Less pronounced divergence was detected between morphologically distinct brackish-water individuals and the remaining shallow-water individuals. The divergence observed between deep-water and shallow-water lineages is consistent with the hypothesis of distinct species. The ambiguous results of species delimitation tests applied to the two shallow-water sub-lineages might instead suggest a process of incipient speciation, even if this hypothesis needs additional evidence. These results suggest that sediment represents the main factor driving genetic divergence and ultimately cryptic speciation in A. assimilis, while other depth-associated factors and geographical barriers do not seem to significantly contribute to the genetic architecture of this species, suggesting the occurrence of wide-range larval dispersal.

This work outlines a comprehensive study of groundwater resources supply in Mozambique’s Great Limpopo National Park buffer zone in Southern Africa. To protect biological diversity and the water resources supply of dispersed communities of the buffer zone is a crucial problem to fix people in the region and, in the meantime, to boost the development of the Limpopo National Park. This work shows the current state of knowledge about this topic and try to point out some suggestions on technical solutions. Some previous studies concluded that two different main factors make a complex water supply in this area: (i) the rainwater distribution, it is hard to transform the rainwater into groundwater resources available for exploitation, and (ii) the common groundwater resources, rich in elements such as Boron (B), Mercury (Hg), Uranium (U), Zinc (Zn) and Lead (Pb). The occurrence of these elements is linked to the presence of groundwater with long residence times, unsafe for people’s health. The methodological approach adopted has been to assess the potential infiltration, applying the inverse hydrogeological budget technique, starting from the main outcropping geological units, in the study area. Due to the lack of meteorological data referred to Limpopo National Park, the gauge stations located in the Kruger National Park during the last 64 years have been, on the whole, considered. The target of the study has been to assess the trend of meteorological data and understand how precipitations could affect groundwater recharge and their availability. Without a strategy of biodiversity conservation and sustainable water resources management, they cannot be reached and guaranteed healthy conditions for local dispersed communities. A hydrogeoethical responsible approach is essential to protect biological diversity and hydrosocial cycle framework with integrative ecosystem services and nature-based solutions.

Unusual and discrepant ABO phenotypes are often due to genetic variants that lead to altered levels or activity of ABO transferases and consequently to altered expression of ABO antigens. This report describes eight genetic alterations found in 15 cases with reduced or undetectable expression of ABO antigens. Forward and reverse ABO grouping was performed by standard gel or tube methods. Adsorption-heat elution and saliva testing for H and A substances followed the AABB technical manual procedures. Genomic DNA extracted from whole blood was PCR-amplified to cover the entire ABOcoding sequence, splice junctions, proximal promoter, and intron 1 enhancer. Amplification products were sequenced by next-generation or Sanger dideoxy methods, either directly or after cloning into a bacterial plasmid vector. Eight unreported alleles were found in the 15 cases analyzed. Alleles ABO*A(28+1C)and ABO*A(29–5G)harbor variants that alter the consensus sequence at the intron 1 donor and acceptor splice sites, respectively. The other alleles harbor variants that alter the consensus sequence at transcription factor–binding sites in the intron 1 enhancer: specifically, ABO*A(28+5792T), ABO*A(28+5859A), and ABO*A(28+5860G)at GATA-1 sites; ABO*B(28+5877T)and ABO*B(28+5878G)at a RUNX1 site; and ABO*A(28+5843A)at or near a C/EBP site. Molecular and serologic characterization of ABOalleles can help in their future identification and in the resolution of discrepancies.

Extreme weather events are increasingly affecting the climate of our planet and they cause natural disasters that are often dangerous to human life. Furthermore, the management of extreme events is very important and can be mitigated by artificial reservoirs, such as those existing in the region. From this point of view, the management of extreme events would become an opportunity for development linked to the production of energy through artificial reservoirs. The aim of this study is to assess the changes of these phenomena, in a small area of central Italy (Marche region), calculating 11 extreme precipitation indices from 1961 to 2017. The analysis shows an extremisation of rain events, with an increase in indices CDD, CWD and R99. However the innovativeness of this research lies in the spatialization of these extreme indices, through areal interpolations performed by GIS software. The territorial assessment of extreme precipitation events has revealed significant local countertrends, useful for hydrogeological protection, water resource management and energy production.

Aims. We report the discovery of very shallow ($\Delta F/F \approx 3.4\times 10^{-4}$), periodic dips in the light curve of an active $V = 11.7$G9V star observed by the CoRoT  satellite, which we interpret as caused by a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion.

We report on an intensive observational campaign carried out with HARPS at the 3.6 m telescope at La Silla on the star CoRoT-7. Additional simultaneous photometric measurements carried out with the Euler Swiss telescope have demonstrated that the observed radial velocity variations are dominated by rotational modulation from cool spots on the stellar surface. Several approaches were used to extract the radial velocity signal of the planet(s) from the stellar activity signal. First, a simple pre-whitening procedure was employed to find and subsequently remove periodic signals from the complex frequency structure of the radial velocity data. The dominant frequency in the power spectrum was found at 23  days, which corresponds to the rotation period of CoRoT-7. The 0.8535 day period of CoRoT-7b planetary candidate was detected with an amplitude of 3.3 m s-1. Most other frequencies, some with amplitudes larger than the CoRoT-7b signal, are most likely associated with activity. A second approach used harmonic decomposition of the rotational period and up to the first three harmonics to filter out the activity signal from radial velocity variations caused by orbiting planets. After correcting the radial velocity data for activity, two periodic signals are detected: the CoRoT-7b  transit period and a second one with a period of 3.69 days and an amplitude of 4 m s-1. This second signal was also found in the pre-whitening analysis. We attribute the second signal to a second, more remote planet CoRoT-7c . The orbital solution of both planets is compatible with circular orbits. The mass of CoRoT-7b is $4.8\pm0.8$($M_{\oplus}$) and that of CoRoT-7c is $8.4\pm 0.9$($M_{\oplus}$), assuming both planets are on coplanar orbits. We also investigated the false positive scenario of a blend by a faint stellar binary, and this may be rejected by the stability of the bisector on a nightly scale. According to their masses both planets belong to the super-Earth planet category. The average density of CoRoT-7b is $\rho=5.6\pm 1.3\mathrm{\,g\,cm^{-3}}$, similar to the Earth. The CoRoT-7 planetary system provides us with the first insight into the physical nature of short period super-Earth planets recently detected by radial velocity surveys. These planets may be denser than Neptune and therefore likely made of rocks like the Earth, or a mix of water ice and rocks.

This paper presents an analysis that searched for systematic effects within the CoRoT exoplanet field light curves. The analysis identified a systematic effect that modified the zero point of most CoRoT exposures as a function of stellar magnitude. We could find this effect only after preparing a set of learning light curves that were relatively free of stellar and instrumental noise. Correcting for this effect, rejecting outliers that appear in almost every exposure, and applying SysRem, reduced the stellar RMS by about 20%, without attenuating transit signals.

The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response function goes from ~400 to ~1000 nm. We used two different filtering approaches, and several methods to evaluate the significance of a detection of the secondary eclipse. We detect a secondary eclipse centered within 20 min at the expected times for a circular orbit, with a depth of $0.016 \pm 0.006$%. The center of the eclipse is translated in a 1-σupper limit to the planet's eccentricity of $e\cos\omega< 0.014$. Under the assumption of a zero Bond Albedo and blackbody emission from the planet, it corresponds to a $T_{\rm CoRoT} = 2330^{+120}_{-140}$K. We provide the equilibrium temperatures of the planet as a function of the amount of reflected light. If the planet is in thermal equilibrium with the incident flux from the star, our results imply an inefficient transport mechanism of the flux from the day to the night sides.

In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet-finding channel, with a particular emphasis on the time scales characteristic of planetary transits. Together with other articles in the same issue of this journal, it forms an attempt to provide the building blocks for a statistical interpretation of the CoRoT planet and eclipsing binary catch to date. After pre-processing the light curves so as to minimise long-term variations and outliers, we measure the scatter of the light curves in the first three CoRoT runs lasting more than 1 month, using an iterative non-linear filter to isolate signal on the time scales of interest. The behaviour of the noise on 2 h time scales is described well by a power-law with index 0.25 in R-magnitude, ranging from 0.1 mmag at $R=11.5$to 1 mmag at $R=16$, which is close to the pre-launch specification, though still a factor 2-3 above the photon noise due to residual jitter noise and hot pixel events. There is evidence of slight degradation in the performance over time. We find clear evidence of enhanced variability on hour time scales (at the level of 0.5 mmag) in stars identified as likely giants from their Rmagnitude and $B-V$colour, which represent approximately 60 and 20% of the observed population in the directions of Aquila and Monoceros, respectively. On the other hand, median correlated noise levels over 2 h for dwarf stars are extremely low, reaching 0.05 mmag at the bright end.

With the release of CoRoT lightcurves of the Initial Run IRa01, 50 transiting planetary candidates have been published in a companion paper. About twenty of them were identified as binary stars from the CoRoT lightcurve itself. Complementary observations were conducted for 29 candidates, including ground-based photometry and radial-velocity measurements. Two giant planets were identified and fully characterized. Nineteen binaries are recognized, from which 10 are background eclipsing binaries in the CoRoT mask or triple systems, diluted by the main CoRoT target. Eight cases remain of unclear origin, one of them still being a planetary candidate. Comparison with simulations shows that the actual threshold of confirmed planet detection in this field does not yet fulfill the expectations, and a number of reasons are invoked, like the ranking process based on lightcurve analyses, and the strategy and limits of follow-up observations for targets fainter than magnitude 15.

Context. The CoRoT satellite searches for planets by applying the transit method, monitoring up to 12 000 stars in the galactic plane for 150 days in each observing run. This search is contaminated by a large fraction of false positives, caused by different eclipsing binary configurations that might be confused with a transiting planet.

The motivation, techniques and performance of the ground-based photometric follow-up of transit detections by the CoRoT space mission are presented. Its principal raison d'êtrearises from the much higher spatial resolution of common ground-based telescopes in comparison to CoRoT's cameras. This allows the identification of many transit candidates as arising from eclipsing binaries that are contaminating CoRoT's lightcurves, even in low-amplitude transit events that cannot be detected with ground-based obervations. For the ground observations, “on” – “off” photometry is now largely employed, in which only a short timeseries during a transit and a section outside a transit is observed and compared photometrically. CoRoTplanet candidates' transits are being observed by a dedicated team with access to telescopes with sizes ranging from 0.2 to 2 m. As an example, the process that led to the rejection of contaminating eclipsing binaries near the host star of the Super-Earth planet CoRoT-7b is shown. Experiences and techniques from this work may also be useful for other transit-detection experiments, when the discovery instrument obtains data with a relatively low angular resolution.

Aims. We present data to improve the known parameters of the HD 17156 system (peculiar due to the eccentricity and long orbital period of its transiting planet) and constrain the presence of stellar companions.

Context. The CoRoTspace mission routinely provides high-precision photometric measurements of thousands of stars that have been continuously observed for months.

Aims. The CoRoT satellite has announced its fourth transiting planet (Aigrain et al. 2008, A&A, 488, L43) with space photometry. We describe and analyse complementary observations of this system performed to establish the planetary nature of the transiting body and to estimate the fundamental parameters of the planet and its parent star.

We report on H-band, ground-based observations of a transit of the hot Neptune GJ 436b. Once combined to achieve sampling equivalent to archived observations taken with Spitzer, our measurements reach comparable precision levels. We analyze both sets of observations in a consistent way, and measure the rate of orbital inclination change to be of 0.02 ±0.04° in the time span between the two observations (253.8 d, corresponding to 0.03 ±0.05° yr-1if extrapolated). This rate allows us to put limits on the relative inclination between the two planets by performing simulations of planetary systems, including a second planet, GJ 436c, whose presence has been recently suggested (Ribas et al. 2008). The allowed inclinations for a 5 $M_{\oplus}$super-Earth GJ 436c in a 5.2 d orbit are within ~7° of the orbit of GJ 436b; for larger differences the observed inclination change can be reproduced only during short sections (<50%) of the orbital evolution of the system. The measured times of three transit centers of the system do not show any departure from linear ephemeris, a result that is only reproduced in <1% of the simulated orbits. Put together, these results argue against the proposed planet candidate GJ 436c.

Context. The CoRoT mission, a pioneer in exoplanet searches from space, has completed its first 150 days of continuous observations of ~12 000 stars in the galactic plane. An analysis of the raw data identifies the most promising candidates and triggers the ground-based follow-up.

Context. The pioneer space mission for photometric planet searches, CoRoT, steadily monitors about 12 000 stars in each of its fields of view. Transit candidates can be detected early in the processing of the data and before the end of a run of observation.

We report the detection of transits by the $3.1~M_{\rm Jup}$companion to the $V=8.17$G0V star HD 17156. The transit was observed by three independant observers on Sep. 9/10, 2007 (two in central Italy and one in the Canary Islands), who obtained detections at confidence levels of 3.0σ, 5.3σ, and 7.9σ, respectively. The observations were carried out under the auspices of the Transitsearch.orgnetwork, which organizes follow-up photometric transit searches of known planet-bearing stars during the time intervals when transits might be expected to occur. Analyses of the 7.9σdata set indicates a transit depth $d=0.0062$±0.0004 and a transit duration $t=186$±5 min. These values are consistent with the transit of a Jupiter-sized planet with an impact parameter $b=a \cos{i}/R_{\star} \sim 0.8$. This planet occupies a unique regime among known transiting extrasolar planets, both as a result of its large orbital eccentricity ($e=0.67$) and long orbital period ($P=21.2~{\rm d}$). The planet receives a 26-fold variation in insolation during the course of its orbit, which will make it a useful object for characterizing exoplanetary atmospheric dynamics.

Aims.If a significant fraction of binary star systems spent some time as inclined triple systems, either during their formation process or as the outcome of several close dynamical encounters in a crowded stellar environemnt, then the number of planets in binaries would be significantly lower than around single stars. The stellar chaotic phase preceding the instability of the triple system and the wide oscillations in eccentricity and inclination of the companion star due to the high mutual inclination between the companion and the singleton would quickly eject planets orbiting the binary in S-type orbits.

Context.Searching for planets in open clusters allows us to study the effects of dynamical environment on planet formation and evolution.

Aims.The present dynamical configuration of planets in binary star systems may not reflect their formation process since the binary orbit may have changed in the past after the planet formation process was completed. An observed binary system may have been part of a former hierarchical triple that became unstable after the planets completed their growth around the primary star. Alternatively, in a dense stellar environment even a single stellar encounter between the star pair and a singleton may singificantly alter the binary orbit. In both cases the planets we observe at present would have formed when the dynamical environment was different from the presently observed one.

Aims.The statistical properties of planets in binaries were investigated. Any difference to planets orbiting single stars can shed light on the formation and evolution of planetary systems. As planets were found around components of binaries with very different separation and mass ratio, it is particularly important to study the characteristics of planets as a function of the effective gravitational influence of the companion.

We numerically investigate under which conditions the planet detected at 2.1 AU from γCepheicould form through the core-accretion scenario despite the perturbing presence of the highly eccentric companion star. We first show that the initial stage of runaway accretion of kilometer-sized planetesimals is possible within 2.5 AU from the central star only if large amounts of gas are present. In this case, gaseous friction induces periastron alignment of the orbits which reduces the otherwise high mutual impact velocities due to the companion's secular perturbations. The following stage of mutual accretion of large embryos is also modeled. According to our simulations, the giant impacts among the embryos always lead to a core of 10 $M_{\oplus}$within 10 Myr, the average lifetime of gaseous discs. However, the core always ends up within 1.5 AU from the central star. Either the core grows more quickly in the inner region of the disc, or it migrates inside by scattering the residual embryos.

We present iron abundance analysis for 23 wide binaries with main sequence components in the temperture range 4900–6300 K, taken from the sample of the pairs currently included in the radial velocity planet search on going at the Telescopio Nazionale Galileo (TNG) using the high resolution spectrograph SARG. The use of a line-by-line differential analysis technique between the components of each pair allows us to reach errors of about 0.02 dex in the iron content difference. Most of the pairs have abundance differences lower than 0.02 dex and there are no pairs with differences larger than 0.07 dex. The four cases of differences larger than 0.02 dex may be spurious because of the larger error bars affecting pairs with large temperature difference, cold stars and rotating stars. The pair HD 219542, previously reported by us to have a different composition, here is shown to be normal. For non-rotating stars warmer than 5500 K, characterized by a thinner convective envelope and for which our analyis appears to be of higher accuracy, we are able to exclude in most cases the consumption of more than 1 Earth Mass of iron (about 5 Earth masses of meteoritic material) during the main sequence lifetime of the stars, placing more stringent limits (about 0.4 Earth masses of iron) in five cases of warm stars. This latter limit is similar to the estimates of rocky material accreted by the Sun during its main sequence lifetime. Combining the results of the present analysis with those for the Hyades and Pleiades, we conclude that the hypothesis that pollution by planetary material is the only mechanism responsible for the highest metallicity of the stars with planets may be rejected at more than 99% level of confidence if the incidence of planets in these samples is as high as 8% and similar to the field stars included in current radial velocity surveys. However, the significance of this result drops considerably if the incidence of planets around stars in binary systems and clusters is less than a half of that around normal field stars.

The star HD 219542 B has been reported by us (Desidera et al. 2003) to show low-amplitude radial velocity variations that could be due to the presence of a Saturn-mass planetary companion or to stellar activity phenomena. In this letter we present the results of the continuation of the radial velocity monitoring as well as a discussion of literature determinations of the chromospheric activity of the star (Wright et al. 2004). These new data indicate that the observed radial velocity variations are likely related to stellar activity. In particular, there are indications that HD 219542 B underwent a phase of enhanced stellar activity in 2002 while the activity level has been lower in both 2001 and 2003. Our 2003 radial velocity measurements now deviate from our preliminary orbital solution and the peak in the power spectrum at the proposed planet period is severely reduced by the inclusion of the new data. We therefore dismiss the planet hypothesis as the cause of the radial velocity variations.

Abundances for $\alpha-$elements and Fe in about 150 field subdwarfs and early subgiants with accurate parallaxes and kinematic data are used to discuss the run of abundance ratios in metal-poor stars in the solar neighborhood. Based on kinematics, we separated stars into two populations: the first one has a positive velocity of rotation around the galactic center, and it is likely to be related to the dissipational collapse of the galaxy; the second one has either negligible or negative rotational velocity, and it is likely related to an accretion component. The two populations show a large overlap in metallicity. However, they show distinct chemical properties. For the first population we found that there are close correlations (with small scatters around) of the rotational velocity with metallicity and with the Fe/αabundance ratio: this might be a signature of a not very fast collapse of the progenitor clouds, with enough time for a significant contribution by SNe Ia, although this result needs to be confirmed by a 3-D/non-LTE study. On the other side, the second population exhibits a larger scatter in both the above mentioned relations, and on average, a larger Fe/αratio at a given metallicity, suggesting a larger scatter in ages. We argue that the lack of stars with moderate rotational velocities and high Fe/αabundance ratios is due to the short merging time for protogalactic clouds with prograde motion, while the presence of a group of counter-rotating stars with this characteristics indicates a much longer typical lifetimes for protogalactic fragments having such a motion. Finally, we found that perigalactic distances correlate with the Fe/αabundance ratios better than the apogalactic distances.

The components of the wide binary HD 219542 were recently found to differ in metallicity by about 0.1 dex (Gratton et al. [CITE]). In this paper, we present the results of 2 years of high precision radial velocity monitoring of these stars performed at the Telecopio Nazionale Galileo (TNG) using the high resolution spectrograph SARG. No indication for radial velocity variations above the measurement errors (~5 m s-1) was found for the metal richer component A. This allows us to place upper mass-limits for planets around this star. HD 219542 B instead shows a low amplitude variation with a 112 day period at a confidence level of ~$96{-}97$%. This might suggest the presence of a Saturn-mass planet, although it is still possible that these variations are due to moderate activity of the star. Tests based on variations of bisectors, stellar magnitude and line equivalent widths were inconclusive so far.

We present element-to-element abundance ratios measured from high dispersion spectra for 150 field subdwarfs and early subgiants with accurate Hipparcos parallaxes (errors <20%). For 50 stars new spectra were obtained with the UVES on Kueyen (VLT UT2), the McDonald 2.7 m telescope, and SARG at TNG. Additionally, literature equivalent widths were taken from the works by Nissen & Schuster, Fulbright, and Prochaska et al. to complement our data. The whole sample includes both thick disk and halo stars (and a few thin disk stars); most stars have metallicities in the range $-2<\rm [Fe/H]<-0.6$. We found our data, that of Nissen & Schuster, and that of Prochaska to be of comparable quality; results from Fulbright scatter a bit more, but they are still of very good quality and are extremely useful due to the large size of his sample. The results of the present analysis will be used in forthcoming papers to discuss the chemical properties of the dissipational collapse and accretion components of our Galaxy.

At present the possible existence of planets around the stars of a close binary system is still matter of debate. Can planetary bodies form in spite of the strong gravitational perturbations of the companion star? We study in this paper via numerical simulation the last stage of planetary formation, from embryos to terrestrial planets in the αCen system, the prototype of close binary systems. We find that Earth class planets can grow around αCen A on a time-scale of 50 Myr. In some of our numerical models the planets form directly in the habitable zone of the star in low eccentric orbits. In one simulation two of the final planets are in a 2:1 mean motion resonance that, however, becomes unstable after 200 Myr. During the formation process some planetary embryos fall into the stars possibly altering their metallicity.

We have reconstructed the galactic orbits of the parent stars of exoplanets. For comparison, we have recalculated the galactic orbits of stars from the Edvardsson et al. ([CITE]) catalog. A comparison between the two samples indicates that stars with planets are not kinematically peculiar. At each perigalactic distance stars with planets have a metallicity systematically larger than the average for the comparison sample. We argue that this result favors scenarios where the presence of planets is the cause of the higher metallicity of stars with planets.

The Osteoarthritis Initiative was a longitudinal study of osteoarthritis that prospectively collected a trove of imaging data including Multi-Echo Spin-Echo (MESE) data for cartilage T2 relaxation time assessment in one knee. While this data remains underutilized, several analyses have been performed over the past years to assess T2 sensitivity to OA exploiting the OAI dataset. However, fitting procedures to compute T2 maps from the MESE data in the OAI largely rely on mono-exponential modelling, which is inherently sub-optimal as it does not account for stimulated echoes produced by RF slice-profile and B1 inhomogeneities and it often fails to account for low SNR in longer TEs. To mitigate errors, a common practice is to drop the first echo and fit the remaining 6 echoes at the expense of discarding information and degrading SNR efficiency. T2 fitting of MESE data using Extended phase graph (EPG) modelling, whether based on nonlinear least square (NLSQ) dictionary matching (DM) or deep learning (DL), can account for stimulated echoes, and can potentially provide more accurate and robust fitting for T2mapping in the OAI.