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Unlike the central nervous system, the peripheral nervous system is capable of regenerating after nerve injury by activating a transcriptional program leading to axonal repair and the restoration of neuronal functions. The coordination and integration of this program are the target of numerous studies to understand the mechanisms in place to reform a fully functional neural circuit. The Dorsal Root Ganglion (DRG) is an anatomical structure studied to understand the mechanisms associated with axonal regeneration. The most studied DRG are those of the L3, L4 and L5 levels (respectively DRG-L3, DRG-L4 and DRG-L5), whose axonal extensions make up the sciatic nerve. However, the individual contribution of each of these DRG to sciatic nerve regeneration after injury remains unknown, as most studies have analyzed these DRG as a whole. The objective of this study was to perform analyzes of the transcriptome within each DRG in control or lesion (nerve crush) conditions in order to identify the specific response of each DRG to a lesion. The first part of this study focused on the expression profile of regeneration-associated genes (RAG). We showed that several RAGs have a strong increase in their expression in DRG-L3 in response to nerve injury, particularly ATF3, Sprr1a and NPY. We noticed that the expression level of RAGs followed a decreasing expression gradient from DRG-L3 to DRG-L5 in response to injury. The second part of this study focused on the identification of injury markers specific to each DRG, which could potentially be new markers of regeneration. We identified 477 genes whose differential expression was specific to DRG-L3, 310 genes specific to DRG-L4, and 249 genes specific to DRG-L5. Genes expressed in response to injury were mainly enriched in immune cellrelated biological processes like CD68, CD38, Ifi207, Saa1. We also identified a few genes, such as Sst and Fancm, that had an overall decrease in expression in each DRG in response to injury. All, Contrairement au système nerveux central, le système nerveux périphérique est capable de se régénérer après une lésion nerveuse en activant un programme transcriptionnel amenant à la réparation axonale et au rétablissement des fonctions neuronales. La coordination et l'intégration de ce programme sont la cible de nombreuses études pour comprendre les mécanismes en place pour reformer un circuit neuronal pleinement fonctionnel. Le Ganglion Dorsal Spinal (en anglais Dorsal Root Ganglion ou DRG) est une structure anatomique étudiée pour comprendre les mécanismes associés à la régénération axonale. Les DRG les plus étudiés sont ceux des niveaux L3, L4 et L5 (respectivement DRG-L3, DRG-L4 et DRG-L5), dont les prolongements axonaux composent le nerf sciatique. Cependant, la contribution individuelle de chacun de ces DRG à la régénération du nerf sciatique après sa lésion reste encore inconnue, car la plupart des études ont analysé ces DRG dans leur ensemble. L’objectif de cette étude a été d’effectuer des analyses du transcriptome au sein de chaque DRG en conditions contrôle ou de lésion (écrasement du nerf) afin d'identifier la réponse spécifique de chaque DRG à cette lésion. La première partie de cette étude s’est focalisée sur le profil d’expression des gènes associés à la régénération (en anglais regeneration-associated genes ou RAG). Nous avons démontré que plusieurs RAG ont une forte augmentation de leur expression dans le DRG-L3 en réponse à la lésion nerveuse, en particulier ATF3, Sprr1a et NPY. Nous montrons aussi que le niveau d’expression des RAG suivait un gradient d’expression décroissant de DRG-L3 à DRG-L5 en réponse à la lésion. La seconde partie de cette étude s’est concentrée sur l’identification de marqueurs de lésion spécifiques à chaque DRG, pouvant potentiellement être de nouveaux marqueurs de la régénération. Nous avons identifié 477 gènes dont l'expression différentielle était spécifique au DRG-L3, 310 gènes spécifiques au DRG-L4 et 249 gènes spécif

Accurately determining bubble wall velocities in first-order phase transitions is of great importance for the prediction of gravitational wave signals and the matter-antimatter asymmetry. However, it is a challenging task which typically depends on the underlying particle physics model. Recently, it has been shown that assuming local thermal equilibrium can provide a good approximation when calculating the bubble wall velocity. In this paper, we provide a model-independent determination of bubble wall velocities in local thermal equilibrium. Our results show that, under the reasonable assumption that the sound speeds in the plasma are approximately uniform, the hydrodynamics can be fully characterized by four quantities: the phase strength $\alpha_n$, the ratio of the enthalpies in the broken and symmetric phases, $\Psi_n$, and the sound speeds in both phases, $c_s$ and $c_b$. We provide a code snippet that allows for a determination of the wall velocity and energy fraction in local thermal equilibrium in any model. In addition, we present a fit function for the wall velocity in the case $c_s = c_b = 1/\sqrt 3$., Comment: 34 pages, 6 figures; v2 matches published version

Mineral dust produced by wind erosion of arid and semi-arid surfaces is a major component of atmospheric aerosol that affects climate, weather, ecosystems, and socio-economic sectors such as human health, transportation, solar energy, and air quality. Understanding these effects and ultimately improving the resilience of affected countries requires a reliable, dense, and diverse set of dust observations, fundamental for the development and the provision of skillful dust forecasts tailored products. The last decade has seen a notable improvement of dust observational capabilities in terms of considered parameters, geographical coverage, and delivery times, as well as of tailored products of interest to both the scientific community and the various end-users. Given this progress, here we review the current state of observational capabilities including in-situ, ground-based and satellite remote sensing observations, in Northern Africa, the Middle East and Europe for the provision of dust information considering the needs of various users. We also critically discuss observational gaps and related unresolved questions while providing suggestions for overcoming the current limitations. Our review aims to be a milestone for discussing dust observational gaps at a global level to address the needs of users, from research communities to non-scientific stakeholders.

Accurately determining bubble wall velocities in first-order phase transitions is of great importance for the prediction of gravitational wave signals and the matter-antimatter asymmetry. However, it is a challenging task which typically depends on the underlying particle physics model. Recently, it has been shown that assuming local thermal equilibrium can provide a good approximation when calculating the bubble wall velocity. In this paper, we provide a model-independent determination of bubble wall velocities in local thermal equilibrium. Our results show that, under the reasonable assumption that the sound speeds in the plasma are approximately uniform, the hydrodynamics can be fully characterized by four quantities: the phase strength $\alpha_n$, the ratio of the enthalpies in the broken and symmetric phases, $\Psi_n$, and the sound speeds in both phases, $c_s$ and $c_b$. We provide a code snippet that allows for a determination of the wall velocity and energy fraction in local thermal equilibrium in any model. In addition, we present a fit function for the wall velocity in the case $c_s = c_b = 1/\sqrt 3$., Comment: 34 pages, 6 figures; v2 matches published version

The baryon asymmetry of the Universe is one of the central motivations to expect physics beyond the Standard Model. In this Snowmass white paper, we review the challenges and opportunities in testing some of the central paradigms that predict physics at scales low enough to expect new experimental data in the next decade. Focusing on theoretical ideas and some of their experimental implications, in particular, we discuss neutron-antineutron transformations, flavor observables, next generation colliders, future neutron facilities, gravitational waves, searches for permanent electric dipole moments, $0\nu \beta \beta $ decay and some future large underground experiments as methods to test post-sphaleron baryogenesis, electroweak baryogenesis, mesogenesis and low scale leptogenesis. Finally, we comment on the cases where high scale physics can be probed through some of these same mechanisms., Comment: White paper to be submitted to the Snowmass Process' Rare Processes and Precision Measurements Frontier, Baryon and Lepton Number Violation Topical Group (This v2 version corrects a missing author and an author's name which was misspelled. Apologies to these authors for this oversight on the part of the submitter!)

Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark discovery, potentially providing a significant clue to some of our most basic, big-picture scientific questions about the Universe. In this white paper, we survey the leading early-Universe mechanisms that may produce a detectable signal -- including inflation, phase transitions, topological defects, as well as primordial black holes -- and highlight the connections to fundamental physics. We review the complementarity with collider searches for new physics, and multimessenger probes of the large-scale structure of the Universe., Comment: contribution to Snowmass 2021; 3 figures, 67 pages

The terminal wall velocity of a first-order phase transition bubble can be calculated from a set of fluid equations describing the scalar fields and the plasma's state. We rederive these equations from the energy-momentum tensor conservation and the Boltzmann equation, without linearizing in the background temperature and fluid velocity. The resulting equations have a finite solution for any wall velocity. We propose a spectral method to integrate the Boltzmann equation, which is simple, efficient and accurate. As an example, we apply this new methodology to the singlet scalar extension of the standard model. We find that all solutions are naturally categorized as deflagrations ($v_w\sim c_s$) or ultrarelativistic detonations ($\gamma_w\gtrsim10$). Furthermore, the contributions from out-of-equilibrium effects are, most of the time, subdominant. Finally, we use these results to propose several approximation schemes with increasing levels of complexity and accuracy. They can be used to considerably simplify the methodology while correctly describing the qualitative behavior of the bubble wall., Comment: 17 pages, 6 figures

Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark discovery, potentially providing a significant clue to some of our most basic, big-picture scientific questions about the Universe. In this white paper, we survey the leading early-Universe mechanisms that may produce a detectable signal -- including inflation, phase transitions, topological defects, as well as primordial black holes -- and highlight the connections to fundamental physics. We review the complementarity with collider searches for new physics, and multimessenger probes of the large-scale structure of the Universe., Comment: contribution to Snowmass 2021; 3 figures, 67 pages

The baryon asymmetry of the Universe is one of the central motivations to expect physics beyond the Standard Model. In this Snowmass white paper, we review the challenges and opportunities in testing some of the central paradigms that predict physics at scales low enough to expect new experimental data in the next decade. Focusing on theoretical ideas and some of their experimental implications, in particular, we discuss neutron-antineutron transformations, flavor observables, next generation colliders, future neutron facilities, gravitational waves, searches for permanent electric dipole moments, $0\nu \beta \beta $ decay and some future large underground experiments as methods to test post-sphaleron baryogenesis, electroweak baryogenesis, mesogenesis and low scale leptogenesis. Finally, we comment on the cases where high scale physics can be probed through some of these same mechanisms., Comment: White paper to be submitted to the Snowmass Process' Rare Processes and Precision Measurements Frontier, Baryon and Lepton Number Violation Topical Group (This v2 version corrects a missing author and an author's name which was misspelled. Apologies to these authors for this oversight on the part of the submitter!)

The baryon asymmetry of the Universe is one of the central motivations to expect physics beyond the Standard Model. In this Snowmass white paper, we review the challenges and opportunities in testing some of the central paradigms that predict physics at scales low enough to expect new experimental data in the next decade. Focusing on theoretical ideas and some of their experimental implications, in particular, we discuss neutron-antineutron transformations, flavor observables, next generation colliders, future neutron facilities, gravitational waves, searches for permanent electric dipole moments, $0\nu \beta \beta $ decay and some future large underground experiments as methods to test post-sphaleron baryogenesis, electroweak baryogenesis, mesogenesis and low scale leptogenesis. Finally, we comment on the cases where high scale physics can be probed through some of these same mechanisms., Comment: White paper to be submitted to the Snowmass Process' Rare Processes and Precision Measurements Frontier, Baryon and Lepton Number Violation Topical Group (This v2 version corrects a missing author and an author's name which was misspelled. Apologies to these authors for this oversight on the part of the submitter!)

Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark discovery, potentially providing a significant clue to some of our most basic, big-picture scientific questions about the Universe. In this white paper, we survey the leading early-Universe mechanisms that may produce a detectable signal -- including inflation, phase transitions, topological defects, as well as primordial black holes -- and highlight the connections to fundamental physics. We review the complementarity with collider searches for new physics, and multimessenger probes of the large-scale structure of the Universe., Comment: contribution to Snowmass 2021; 3 figures, 67 pages

The baryon asymmetry of the Universe is one of the central motivations to expect physics beyond the Standard Model. In this Snowmass white paper, we review the challenges and opportunities in testing some of the central paradigms that predict physics at scales low enough to expect new experimental data in the next decade. Focusing on theoretical ideas and some of their experimental implications, in particular, we discuss neutron-antineutron transformations, flavor observables, next generation colliders, future neutron facilities, gravitational waves, searches for permanent electric dipole moments, $0\nu \beta \beta $ decay and some future large underground experiments as methods to test post-sphaleron baryogenesis, electroweak baryogenesis, mesogenesis and low scale leptogenesis. Finally, we comment on the cases where high scale physics can be probed through some of these same mechanisms., Comment: White paper to be submitted to the Snowmass Process' Rare Processes and Precision Measurements Frontier, Baryon and Lepton Number Violation Topical Group (This v2 version corrects a missing author and an author's name which was misspelled. Apologies to these authors for this oversight on the part of the submitter!)

Le plexus choroïde (PC) est un tissu épithélial situé dans chaque ventricule du cerveau. Le PC joue un rôle clé dans le maintien de l'homéostasie cérébrale en régulant des fonctions importantes telles que la production de liquide céphalo-rachidien (LCR), la maintien de la barrière hémato-LCR (BCSFB), l'élimination de métabolites du cerveau et la sécrétion de molécules dans le LCR. Au cours du vieillissement, le PC montre un déclin de ses fonctions, augmentant le risque de développer des maladies neurodégénératives. Les mécanismes moléculaires sous-jacents aux changements physiologiques sont largement inconnus. Une précédente étude du laboratoire a évalué l'impact du vieillissement sur la signature transcriptomique du plexus choroïde du ventricule latéral (PCVL) de souris âgées de 6, 12, 18 et 24 mois. Les résultats ont montré que certains gènes présentent un changement progressif d’expression de 6 à 24 mois, tandis que d'autres gènes présentent un changement brusque d'expression entre 18 et 24 mois. Les gènes dont l'expression diminue brusquement avec l'âge sont impliqués dans la régulation de la chromatine, reliant directement le vieillissement de la PC à l'une des principales caractéristiques du vieillissement : les altérations épigénétiques. Cependant, d'autres investigations sont nécessaires pour comprendre le vieillissement du PC. L'objectif de cette étude était de caractériser les changements d'autres molécules importantes (chromatine et protéines) ainsi que d'identifier les changements morphologiques du PC au cours du vieillissement et de vérifier s'ils correspondent à des changements d’une des couches de régulation (ADN, ARN, protéines). L'étude morphologique de PCVL de souris âgées de 6, 12, 18 et 24 mois a démontré que la membrane basale augmentait progressivement au cours du vieillissement tandis que la hauteur et la surface des cellules diminuaient brutalement à 24 mois. Nous avons montré que les changements d'expression des régulateurs de la chromatine, The Choroid plexus (CP) is an epithelial tissue located in each brain ventricle. The CP plays a key role in maintaining the brain homeostasis by regulating important functions such as the production of the Cerebrospinal Fluid (CSF), the protection of the brain through the physical barrier called the Blood-CSF-Barrier (BCSFB), the removal of brain metabolites and the secretion of signaling molecules within the CSF. During aging, the CP shows a decline in its functions, increasing the risk of developing neurodegenerative diseases. The molecular mechanisms underlying the physiological changes are largely unknown. A former lab student has evaluated the impact of aging on the transcriptomic signature of the Lateral Ventricle Choroid Plexus (LVCP) collected from mice aged 6, 12, 18 and 24 months. The results showed two patterns of differential gene expression: some genes exhibit a gradual change in their expression from 6 to 24 months of age while other genes show an abrupt change of expression between 18 and 24 months. Gene ontology (GO) analyses show that genes whose expression decreases abruptly with age are involved in chromatin regulation, potentially directly linking CP aging to one of the main hallmarks of aging: epigenetic alterations. Further investigations are required to fully understand CP aging. The objective of this study was to address the age-related changes of other important molecules (chromatin and proteins) but also to identify the CP morphological changes during aging and verify whether they match pattern(s) in any of the layers of regulation (DNA, RNA, proteins). LVCPs were dissected from male and female C57/BL6 mice aged 6, 12, 18, and 24 months obtained from the Réseau Québécois de Recherche sur le Vieillissement (RQRV). The morphological study of the CP demonstrated that the basal membrane increased gradually during aging while the cells height and area were abruptly decreased at 24 months of age. We showed that changes in expression of

Supersymmetry is a highly motivated theoretical framework, whose scale of breaking may be at PeV energies, to explain null searches at the Large Hadron Collider. SUSY breaking through a first order phase transition may have occurred in the early universe, leading to potential gravitational wave signals. Constructing a realistic model for gauge-mediated supersymmetry breaking, we show that such a transition can also induce masses for heavy right-handed neutrinos and sneutrinos, whose CP-violating decays give leptogenesis at the PeV scale, and a novel mechanism of neutrino mass generation at one loop. For the same models we predict the possible gravity wave signals, and we study the possibility of production of primordial black holes during the phase transition., Comment: 19 pages, 8 figures

The terminal wall velocity of a first-order phase transition bubble can be calculated from a set of fluid equations describing the scalar fields and the plasma's state. We rederive these equations from the energy-momentum tensor conservation and the Boltzmann equation, without linearizing in the background temperature and fluid velocity. The resulting equations have a finite solution for any wall velocity. We propose a spectral method to integrate the Boltzmann equation, which is simple, efficient and accurate. As an example, we apply this new methodology to the singlet scalar extension of the standard model. We find that all solutions are naturally categorized as deflagrations ($v_w\sim c_s$) or ultrarelativistic detonations ($\gamma_w\gtrsim10$). Furthermore, the contributions from out-of-equilibrium effects are, most of the time, subdominant. Finally, we use these results to propose several approximation schemes with increasing levels of complexity and accuracy. They can be used to considerably simplify the methodology while correctly describing the qualitative behavior of the bubble wall., Comment: 17 pages, 6 figures

Le vieillissement se caractérise par l'accumulation de changements physiologiques au fil du temps qui conduisent à une diminution des fonctions cellulaires et tissulaires. Le cerveau est l'un des organes qui vieillit le plus rapidement et son vieillissement est le premier facteur de risque de nombreuses maladies neurodégénératives. Le cortex frontal (CF) est une couche cellulaire responsable de nombreuses fonctions cognitives, telle que la planification, la mémoire et la décision logique. Au niveau cellulaire, le vieillissement du CF modifie de nombreux composants cellulaires tels que le niveau d'ARNm et de protéines. Le but de cette recherche est d’étudier la dynamique du transcriptome (ARNm) et du protéome (protéines) au cours du vieillissement dans le CF de souris. Notre hypothèse est qu'au cours du vieillissement, il existe deux groupes de gènes qui présentent des types de dérégulation différents : i) une dérégulation transcriptionnelle, avec une modification du niveau d'ARNm corrélée à celle des protéines, et ii) une dérégulation post-transcriptionnelle où la dynamique de l'ARN ne se reflète pas dans les niveaux de protéines. L’objectif est de tester quel(s) types de dérégulation existe lors du vieillissement du CF. Des tissus de CF de souris ont été prélevés sur des souris âgées de 6 et 24 mois. Le séquençage de l'ARN a été réalisé pour établir le profilage de l'expression génique et évaluer les différences transcriptomiques dans le CF vieillissant. Nous observons une augmentation de l’expression de gènes (n= 399) liés aux fonctions immunitaires et une diminution de l’expression de gènes (n=27) liés aux fonctions neuronales. Par spectrométrie de masse, nous avons aussi caractérisé les changements d’abondance de protéines au cours du vieillissement. Nous n’avons pas été capables de confirmer l’enrichissement de protéines aux fonctions immunitaires probablement car la présence de ces cellules est minoritaire dans le tissu et leur détection plus difficile. Cette, Aging is characterized by the accumulation of physiological changes over time that lead to a decline in cell and tissue function. The brain is one of the organs that ages the fastest and its aging is the first risk factor for many neurodegenerative diseases. The frontal cortex (FC) is a cell layer responsible for many cognitive functions, such as planning, memory, and logical decision-making. At the cellular level, FC aging alters many cellular components such as mRNA and protein levels. The aim of this research is to study the dynamics of transcriptome (mRNA) and proteome (proteins) during aging in mouse FC. Our hypothesis is that during aging, there are two groups of genes that show different types of dysregulation: i) transcriptional dysregulation, with a modification of the level of mRNA correlated with that of proteins, and ii) post -transcriptional where RNA dynamics are not reflected in protein levels. The objective is to test which type(s) of dysregulation exist during the aging of the FC. Mouse FC tissues were collected from 6- and 24-month-old mice. RNA sequencing was performed to establish gene expression profiling and assess transcriptomic differences in aging FC. We observed an increase in the expression of genes (n=399) related to immune functions and a decrease in the expression of genes (n=27) related to neuronal functions. By mass spectrometry, we have also characterized the changes in protein abundance during aging. We were not able to confirm the enrichment of proteins with immune functions, probably because the presence of these cells is a minority in the tissue and their detection is more difficult. Therefore, this transcriptional dysregulation, which seems to affect immune cells, remains to be validated by other methodologies, but suggests that it may be at the origin of the neuroinflammation linked to aging in the brain. However, we identified and quantified many proteins whose abundance changes in aging CF. We showed that the RNAs

Electroweak baryogenesis (EWBG) is sourced by nonstandard $CP$-violating interactions of the Higgs boson with fermions, usually taken to be the top quark, enhanced by its large Yukawa coupling. Numerous papers have studied EWBG sourced by lighter fermions, including the tau lepton and off-diagonal quark mass terms. We critically reassess the viability of EWBG in these scenarios, comparing the predictions based on the semiclassical (WKB) formalism for the source term to those from the VEV insertion approximation (VIA), using updated values for the collision terms, and clarifying discrepancies in the definition of the weak sphaleron rate. The VIA systematically predicts a baryon asymmetry that is orders of magnitude larger than the WKB formalism. We trace this to the differing shapes of the $CP$-violating source terms in the two formalisms, showing that the additional spatial derivative in the WKB source term causes large cancellations when it is integrated over the bubble wall profile. An important exception is a source term from $c$-$t$ quark mixing, where the WKB prediction also allows for a realistically large baryon asymmetry. In contrast, the analogous $b$-$s$ mixing source is found to be orders of magnitude too small., Comment: 13 pages, 4 figures

Electroweak baryogenesis (EWBG) is sourced by nonstandard $CP$-violating interactions of the Higgs boson with fermions, usually taken to be the top quark, enhanced by its large Yukawa coupling. Numerous papers have studied EWBG sourced by lighter fermions, including the tau lepton and off-diagonal quark mass terms. We critically reassess the viability of EWBG in these scenarios, comparing the predictions based on the semiclassical (WKB) formalism for the source term to those from the VEV insertion approximation (VIA), using updated values for the collision terms, and clarifying discrepancies in the definition of the weak sphaleron rate. The VIA systematically predicts a baryon asymmetry that is orders of magnitude larger than the WKB formalism. We trace this to the differing shapes of the $CP$-violating source terms in the two formalisms, showing that the additional spatial derivative in the WKB source term causes large cancellations when it is integrated over the bubble wall profile. An important exception is a source term from $c$-$t$ quark mixing, where the WKB prediction also allows for a realistically large baryon asymmetry. In contrast, the analogous $b$-$s$ mixing source is found to be orders of magnitude too small., Comment: 13 pages, 4 figures

The choroid plexus (ChP) produces cerebrospinal fluid and forms an essential brain barrier. ChP tissues form in each brain ventricle, each one adopting a distinct shape, but remarkably little is known about the mechanisms underlying ChP development. Here, we show that epithelial WNT5A is crucial for determining fourth ventricle (4V) ChP morphogenesis and size in mouse. Systemic Wnt5a knockout, or forced Wnt5a overexpression beginning at embryonic day 10.5, profoundly reduced ChP size and development. However, Wnt5a expression was enriched in Foxj1-positive epithelial cells of 4V ChP plexus, and its conditional deletion in these cells affected the branched, villous morphology of the 4V ChP. We found that WNT5A was enriched in epithelial cells localized to the distal tips of 4V ChP villi, where WNT5A acted locally to activate non-canonical WNT signaling via ROR1 and ROR2 receptors. During 4V ChP development, MEIS1 bound to the proximal Wnt5a promoter, and gain- and loss-of-function approaches demonstrated that MEIS1 regulated Wnt5a expression. Collectively, our findings demonstrate a dual function of WNT5A in ChP development and identify MEIS transcription factors as upstream regulators of Wnt5a in the 4V ChP epithelium., For erratum, see (DOI): 10.1242/dev.200517

We study gravity wave production and baryogenesis at the electroweak phase transition, in a real singlet scalar extension of the Standard Model, including vector-like top partners to generate the CP violation needed for electroweak baryogenesis (EWBG). The singlet makes the phase transition strongly first-order through its coupling to the Higgs boson, and it spontaneously breaks CP invariance through a dimension-5 contribution to the top quark mass term, generated by integrating out the heavy top quark partners. We improve on previous studies by incorporating updated transport equations, compatible with large bubble wall velocities. The wall speed and thickness are computed directly from the microphysical parameters rather than treating them as free parameters, allowing for a first-principles computation of the baryon asymmetry. The size of the CP-violating dimension-5 operator needed for EWBG is constrained by collider, electroweak precision, and renormalization group running constraints. We identify regions of parameter space that can produce the observed baryon asymmetry or observable gravitational (GW) wave signals. Contrary to standard lore, we find that for strong deflagrations, the efficiencies of large baryon asymmetry production and strong GW signals can be positively correlated. However we find the overall likelihood of observably large GW signals to be smaller than estimated in previous studies. In particular, only detonation-type transitions are predicted to produce observably large gravitational waves., Comment: 29 pages, 10 figures; v2: GW spectrum corrected, conclusions changed, references added

Electroweak baryogenesis (EWBG) is sourced by nonstandard $CP$-violating interactions of the Higgs boson with fermions, usually taken to be the top quark, enhanced by its large Yukawa coupling. Numerous papers have studied EWBG sourced by lighter fermions, including the tau lepton and off-diagonal quark mass terms. We critically reassess the viability of EWBG in these scenarios, comparing the predictions based on the semiclassical (WKB) formalism for the source term to those from the VEV insertion approximation (VIA), using updated values for the collision terms, and clarifying discrepancies in the definition of the weak sphaleron rate. The VIA systematically predicts a baryon asymmetry that is orders of magnitude larger than the WKB formalism. We trace this to the differing shapes of the $CP$-violating source terms in the two formalisms, showing that the additional spatial derivative in the WKB source term causes large cancellations when it is integrated over the bubble wall profile. An important exception is a source term from $c$-$t$ quark mixing, where the WKB prediction also allows for a realistically large baryon asymmetry. In contrast, the analogous $b$-$s$ mixing source is found to be orders of magnitude too small., Comment: 13 pages, 4 figures

We study gravity wave production and baryogenesis at the electroweak phase transition, in a real singlet scalar extension of the Standard Model, including vector-like top partners to generate the CP violation needed for electroweak baryogenesis (EWBG). The singlet makes the phase transition strongly first-order through its coupling to the Higgs boson, and it spontaneously breaks CP invariance through a dimension-5 contribution to the top quark mass term, generated by integrating out the heavy top quark partners. We improve on previous studies by incorporating updated transport equations, compatible with large bubble wall velocities. The wall speed and thickness are computed directly from the microphysical parameters rather than treating them as free parameters, allowing for a first-principles computation of the baryon asymmetry. The size of the CP-violating dimension-5 operator needed for EWBG is constrained by collider, electroweak precision, and renormalization group running constraints. We identify regions of parameter space that can produce the observed baryon asymmetry or observable gravitational (GW) wave signals. Contrary to standard lore, we find that for strong deflagrations, the efficiencies of large baryon asymmetry production and strong GW signals can be positively correlated. However we find the overall likelihood of observably large GW signals to be smaller than estimated in previous studies. In particular, only detonation-type transitions are predicted to produce observably large gravitational waves., Comment: 29 pages, 10 figures; v2: GW spectrum corrected, conclusions changed, references added

Tamas Fulop,1 Shreyansh Tripathi,2,3 Serafim Rodrigues,3,4 Mathieu Desroches,5,6 Ton Bunt,7 Arnold Eiser,8 Francois Bernier,9 Pascale B Beauregard,10 Annelise E Barron,11 Abdelouahed Khalil,1 Adam Plotka,12 Katsuiku Hirokawa,13 Anis Larbi,14 Christian Bocti,15 Benoit Laurent,16 Eric H Frost,17 Jacek M Witkowski12 1Research Center on Aging, Geriatric Division, Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada; 2Cluster Innovation Centre, North Campus, University of Delhi, Delhi, 110007, India; 3Ikerbasque, The Basque Foundation for Science, Bilbao, Spain; 4Mathematical Computational and Experimental Neuroscience (MCEN), BCAM - The Basque Center for Applied Mathematics, Bilbao, Spain; 5MathNeuro Team, Inria Sophia Antipolis Méditerranée, Sophia Antipolis, France; 6Department of Mathematics, Université Côte d’Azur, Nice, France; 7Izumi Biosciences, Inc., Lexington, MA, USA; 8Leonard Davis Institute, University of Pennsylvania, Drexel University College of Medicine, Philadelphia, PA, USA; 9Morinaga Milk Industry Co., Ltd, Next Generation Science Institute, Kanagawa, Japan; 10Department of Biology, Faculty of Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada; 11Department of Bioengineering, Stanford School of Medicine, Stanford, CA, USA; 12Department of Pathophysiology, Medical University of Gdansk, Gdansk, Poland; 13Institute of Health and Life Science, Tokyo Med. Dent. University, Tokyo and Nito-Memory Nakanosogo Hospital, Department of Pathology, Tokyo, Japan; 14Singapore Immunology Network (SIgN), Agency for Science Technology and Research (A*STAR), Immunos Building, Biopolis, Singapore, Singapore; 15Research Center on Aging, Department of Medicine, Division of Neurology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada; 16Research Center on Aging, Department

The cosmological electroweak phase transition can be strongly first order in extended particle physics models. To accurately predict the speed and shape of the bubble walls during such a transition, Boltzmann equations for the CP-even fluid perturbations must be solved. We point out that the equations usually adopted lead to unphysical behavior of the perturbations, for walls traveling close to or above the speed of sound in the plasma. This is an artifact that can be overcome by more carefully truncating the full Boltzmann equation. We present an improved set of fluid equations, suitable for studying the dynamics of both subsonic and supersonic walls, of interest for gravitational wave production and electroweak baryogenesis., Comment: 9 pages, 3 figures; v2: corrected sign error in code, figures changed; v3: corrected sign error in Eq. (16), references updated

The cosmological electroweak phase transition can be strongly first order in extended particle physics models. To accurately predict the speed and shape of the bubble walls during such a transition, Boltzmann equations for the CP-even fluid perturbations must be solved. We point out that the equations usually adopted lead to unphysical behavior of the perturbations, for walls traveling close to or above the speed of sound in the plasma. This is an artifact that can be overcome by more carefully truncating the full Boltzmann equation. We present an improved set of fluid equations, suitable for studying the dynamics of both subsonic and supersonic walls, of interest for gravitational wave production and electroweak baryogenesis., Comment: 9 pages, 3 figures; v2: corrected sign error in code, figures changed; v3: corrected sign error in Eq. (16), references updated

The cosmological electroweak phase transition can be strongly first order in extended particle physics models. To accurately predict the speed and shape of the bubble walls during such a transition, Boltzmann equations for the CP-even fluid perturbations must be solved. We point out that the equations usually adopted lead to unphysical behavior of the perturbations, for walls traveling close to or above the speed of sound in the plasma. This is an artifact that can be overcome by more carefully truncating the full Boltzmann equation. We present an improved set of fluid equations, suitable for studying the dynamics of both subsonic and supersonic walls, of interest for gravitational wave production and electroweak baryogenesis., Comment: 9 pages, 3 figures; v2: corrected sign error in code, figures changed; v3: corrected sign error in Eq. (16), references updated

The choroid plexus (CP) is an epithelial tissue located in each of the ventricles of the brain (lateral, third and fourth ventricles) and where it sits on a stroma like-bed above a network of fenestrated blood capillaries. Water, nutrients and other substances are filtered from the blood into the brain’s ventricles through the CP epithelium to produce the cerebrospinal fluid (CSF). The CP-CSF system is crucial for the protection and maintenance of brain homeostasis. The CP also plays an active role in the development and repair of the brain. It is strategically positioned within the ventricles to secrete active key molecules, some of them being important for the proliferation of neural stem cells in the developing and adult brain. Throughout the lifespan, the CP goes through a natural and gradual aging process in which there are morphological changes in the tissue. These modifications alter the CP functionality, such as the filtering and secreting properties. However, it is not clear whether these changes occur progressively during aging. The goal of this study is to characterize the impact of aging on the transcriptomic signature of the CP. Lateral Ventricle Choroid Plexus (LVCP) tissue was micro-dissected and collected from mice aged 6, 12, 18 and 24 months available through the RQRV (Réseau Québécois de Recherche sur le Vieillissement). RNA sequencing was performed to establish gene-expression profiling and evaluate the transcriptomic differences in the LVCP over the mouse lifespan. We found two patterns of differential gene expression during CP aging. Some genes exhibited a gradual increase or decrease of their expression from 6 months to 24 months of age while other genes showed an abrupt increase or decrease of expression between 18 months and 24 months of age. Gene ontology analysis indicated a decrease of genes involved in important brain functions during aging (i.e. generation of neurons, metal ion transport, synaptic transmission), while genes th, Le plexus choroïde (PC) est un épithélium situé dans chacun des ventricules du cerveau (ventricules latéraux, troisième et quatrième ventricules) où il repose sur un stroma au-dessus d'un réseau de capillaires sanguins fenestrés. L’eau, les nutriments et d’autres substances sont filtrés du sang vers les ventricules du cerveau à travers l’épithélium du CP pour produire le liquide cérébrospinal (LCS). Le système PC-LCS est donc crucial pour la protection et le maintien de l'homéostasie cérébrale. Le PC joue également un rôle actif dans le développement et la réparation du cerveau. Il est stratégiquement positionné dans les ventricules pour sécréter des molécules clés actives, certaines d'entre elles étant importantes pour la prolifération des cellules souches neurales dans le cerveau au cours du développement et chez l’adulte. Au cours de la vie, le PC subit un processus de vieillissement naturel et progressif dans lequel il y a des changements morphologiques dans le tissu. Ces modifications modifient la fonctionnalité du PC, comme les propriétés de filtrage et de sécrétion. Cependant, il n'est pas clair si ces changements se produisent progressivement au cours du vieillissement. Le but de cette étude est de caractériser l'impact du vieillissement sur la signature transcriptomique du PC. Le plexus choroïde du ventricule latéral (PCVL) a été microdisséqué et prélevé sur des souris âgées de 6, 12, 18 et 24 mois disponibles via le RQRV (Réseau Québécois de Recherche sur le Vieillissement). Le séquençage de l'ARN a été effectué pour établir le profil d'expression génique et évaluer les différences transcriptomiques dans le PCVL au cours de la vie de la souris. Nos résultats montrent deux modèles d'expression différentielle des gènes au cours du vieillissement du PC. Certains gènes montrent une augmentation ou une diminution graduelle de leur expression de 6 mois à 24 mois tandis que d'autres gènes montrent une augmentation ou une diminution brutale de l'expression entre 1

Lysine-specific demethylase 1 (LSD1) has been reported to repress and activate transcription by mediating histone H3K4me1/2 and H3K9me1/2 demethylation, respectively. The molecular mechanism that underlies this dual substrate specificity has remained unknown. Here we report that an isoform of LSD1, LSD1+8a, does not have the intrinsic capability to demethylate H3K4me2. Instead, LSD1+8a mediates H3K9me2 demethylation in collaboration with supervillin (SVIL), a new LSD1+8a interacting protein. LSD1+8a knockdown increases H3K9me2, but not H3K4me2, levels at its target promoters and compromises neuronal differentiation. Importantly, SVIL co-localizes to LSD1+8a-bound promoters, and its knockdown mimics the impact of LSD1+8a loss, supporting SVIL as a cofactor for LSD1+8a in neuronal cells. These findings provide insight into mechanisms by which LSD1 mediates H3K9me demethylation and highlight alternative splicing as a means by which LSD1 acquires selective substrate specificities (H3K9 versus H3K4) to differentially control specific gene expression programs in neurons.