Context. Eclipsing time variations are observed in many close binary systems. In particular, for several post-common-envelope binaries (PCEBs) that consist of a white dwarf and a main sequence star, ...the observed-minus-calculated (O–C) diagram suggests that real or apparent orbital period variations are driven by Jupiter-mass planets or as a result of magnetic activity, the so-called Applegate mechanism. The latter explains orbital period variations as a result of changes in the stellar quadrupole moment due to magnetic activity. Aims. In this work we explore the feasibility of driving eclipsing time variations via the Applegate mechanism for a sample of PCEB systems, including a range of different rotation rates. Methods. We used the MESA code to evolve 12 stars with different masses and rotation rates. We applied simple dynamo models to their radial profiles to investigate the scale at which the predicted activity cycle matches the observed modulation period, and quantifiy the uncertainty. We further calculated the required energies to drive the Applegate mechanism. Results. We show that the Applegate mechanism is energetically feasible in 5 PCEB systems. In RX J2130.6+4710, it may be feasible as well considering the uncertainties. We note that these are the systems with the highest rotation rate compared to the critical rotation rate of the main-sequence star. Conclusions. The results suggest that the ratio of physical to critical rotation rate in the main sequence star is an important indicator for the feasibility of Applegate’s mechanism, but exploring larger samples will be necessary to probe this hypothesis.
We uncovered the morphology of quantum vortex structures in positron-atom ionization collisions. By performing an exhaustive calculation of the position of vortices in the final momentum space of the ...problem with only one kinematic restriction, we could elucidate that quantum vortices form a closed structure, which is one of the two possible scenarios for their emergence in three dimensions. This is the first time that these structures are fully calculated for positron atom collisions.
Abstract Immune mediators affect multiple biological functions of intestinal epithelial cells (IECs) and, like Paneth and Paneth‐like cells, play an important role in intestinal epithelial ...homeostasis. IFN‐γ a prototypical proinflammatory cytokine disrupts intestinal epithelial homeostasis. However, the mechanism underlying the process remains unknown. In this study, using in vivo and in vitro models we demonstrate that IFN‐γ is spontaneously secreted in the small intestine. Furthermore, we observed that this cytokine stimulates mitochondrial activity, ROS production, and Paneth and Paneth‐like cell secretion. Paneth and Paneth‐like secretion downstream of IFN‐γ, as identified here, is mTORC1 and necroptosis‐dependent. Thus, our findings revealed that the pleiotropic function of IFN‐γ also includes the regulation of Paneth cell function in the homeostatic gut.
Adult stromal mesenchymal stem cells (MSCs) have been postulated as responsible for cell renewal in highly and continuously regenerative tissues such as the endometrium. MSCs have been identified in ...the endometrium of many species including humans, rodents, pets and some farm animals, but not in horses. The objective of this work was to isolate such cells from the endometrium of mares and to compare their main biological attributes with horse adipose-derived MSCs. Here we successfully isolated and characterized endometrial MSCs (eMSCs) from mares. Said cells showed fibroblast-like morphology, grew on plastic, had doubling population times of 46.4 ± 3.38 h, underwent tri-lineage (osteo, chondro and adipogenic) differentiation after appropriate inductions, migrated toward the attraction of fetal calf serum and displayed a pattern of surface markers commonly accepted for horse MSCs. All these are properties of MSCs. Some of these attributes were shared with equine adipose-derived MSCs, but the migration pattern of eMSC at 12 and 24 h after stimulation was reduced in comparison with adipose MSCs. Also, expression of CD44, CD90 and MHCI surface markers were dramatically down-regulated in eMSCs. In conclusion, equine-derived endometrial MSC share biological attributes with adipose MSC of this species, but displayed a different surface marker phenotype and an impaired migration ability. Conceivably, this phenotype is distinctive for MSC of this origin.
•Mesenchymal stem cells from endometrium of mares were isolated and characterized.•Similar biological properties than adipose derived mesenchymal stem cells.•Lower migration ability than adipose mesenchymal cells.•Differential expression pattern of surface markers.
Synopsis We analyze the influence of the coherence of the projectile's beam in scattering phenomena. We focus our study in the ionization of He by C6+ projectiles at 100 MeV/amu. Our calculations, ...which had been previously performed for only the scattering and perpendicular collision planes and within the First Born approximation, were repeated for an ampler set of collision planes and with a more refined model. We obtain a very good agreement with the experimental results.
Mucosal innate immunity functions as the first line of defense against invading pathogens. Members of the IL-1 family are key cytokines upregulated in the inflamed mucosa. Inflammatory cytokines are ...regulated by limiting their function and availability through their activation and secretion mechanisms. IL-1 cytokines secretion is affected by the lack of a signal peptide on their sequence, which prevents them from accessing the conventional protein secretion pathway; thus, they use unconventional protein secretion pathways. Here we show in mouse macrophages that LPS/ATP stimulation induces cytokine relocalization to the plasma membrane, and conventional secretion blockade using monensin or Brefeldin A triggers no IL-36γ accumulation within the cell.
In silico
modeling indicates IL-36γ can pass through both the P2X7R and Gasdermin D pores, and both IL-36γ, P2X7R and Gasdermin D mRNA are upregulated in inflammation; further, experimental blockade of these receptors’ limits IL-36γ release. Our results demonstrate that IL-36γ is secreted mainly by an unconventional pathway through membrane pores formed by P2X7R and Gasdermin D.
Synopsis We numerical and analytically investigate the electron dynamics of high-order harmonic generation (HHG) in solids driven by strong mid-infrared few-cycle laser pulses. Our numerical model ...distinguishes contributions to the HH yield from (i) intra- and interband transitions and (ii) the central Γ-point of the first Brillouin zone (BZ) versus the entire first BZ of the initial valence band.
Extracellular vesicles (EVs) have become important in embryo-maternal communication during early development. The aim of this study was to evaluate the effect of an in vitro system on early ...bidirectional embryo-maternal communication mediated by EVs. For this purpose, two experiments were performed: one to evaluate the effect of embryonic EVs on maternal cells and the second to determine the effect of maternal EVs on early embryonic development. For the first in vitro (IVP) and in vivo (IVV) experiments, bovine blastocysts were selected and individually cultured for 48 h to collect embryonic EVs secreted during days 7-9 of embryonic development. Embryonic EVs were added to the medium of in vitro-cultured bovine endometrial cells to evaluate their effect on the expression pattern of genes associated with endometrial function and response to interferon tau (IFNT). Non-classical interferon-stimulated genes (ISGs) were only induced by in vitro-derived embryos. In the second experiment, EVs released by endometrial cells cultured in vitro (EVC) and collected from uterine fluid (EV-UF) of cows in the early luteal phase were added to the culture medium of bovine embryos produced in vitro during days 5-9 of development. The effect of maternal in vitro or in vivo-derived EVs differs in the quality of bovine embryos produced in vitro during the pre-implantation period. The expression of IFNT in bovine embryos is increased by the effect of EV-UF treatment. Additionally, EV-UF treatment induces a sustained increase in diameter during embryonic development and a tendency towards a greater number of expanded and hatched blastocysts. However, some genes related to embryo quality are induced by EVC treatment.
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