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Macrophages are highly heterogeneous immune cells that fulfill tissue-specific functions. Tissue-derived signals play a critical role in determining macrophage heterogeneity. However, these signals remain largely unknown. The BMP receptor activin receptor-like kinase 1 (ALK1) is well known for its role in blood vessel formation; however, its role within the immune system has never been revealed to our knowledge. Here, we found that BMP9/BMP10/ALK1 signaling controlled the identity and self-renewal of Kupffer cells (KCs) through a Smad4-dependent pathway. In contrast, ALK1 was dispensable for the maintenance of macrophages located in the lung, kidney, spleen, and brain. Following ALK1 deletion, KCs were lost over time and were replaced by monocyte-derived macrophages. These hepatic macrophages showed significantly reduced expression of the complement receptor VSIG4 and alterations in immune zonation and morphology, which is important for the tissue-specialized function of KCs. Furthermore, we found that this signaling pathway was important for KC-mediated Listeria monocytogenes capture, as the loss of ALK1 and Smad4 led to a failure of bacterial capture and overwhelming disseminated infections. Thus, ALK1 signaling instructs a tissue-specific phenotype that allows KCs to protect the host from systemic bacterial dissemination., Introduction Kupffer cells (KCs) are resident macrophages in the liver and constitute 80%-90% of the tissue macrophages present in the body. They are predominantly derived from fetal liver monocytes (1-4). [...]

"Scholars of the Usul -early and recent- have paid utmost importance to the Maqâsid al-Shariah or the Objectives of Shariah and tried to substantiate, associate and link them with its sources, Qur’an and Sunnah, then to derive from them the Legislator’s or the Shari‘s purpose, the revelation’s true purpose and how it benefits the creatures in terms of promoting what is in their interest and shunning away what is harmful. These objectives became the point of interest for the jurists and scholars who toiled to understand the texts and what they connoted and they continue to venture into its depths and extract its treasures. It becomes quite evident from their exegeses of Qur’an and the Prophetic Traditions and elucidations of the juristic principles and issues. Imam al-Shâtibī and Ibn ‘Ashoor are two such scholars in this field who studied the Objectives of Shariah and contributed to this discipline so greatly that they became reference points for those who came after them. The basic principles in the field that were inferred by them are still its pillars. The Objectives of Shariah are divided into four kinds with reference to their benefits: the necessities, needs, improvements and supplements. The necessities are further divided into protection of Deen, protection of self, of intellect, of possessions and of race among others. Prudence demands that all means should be employed to safeguard these necessities. Thus knowing the Objectives of Shariah and their promulgation among the masses is quite important for the society since it leads towards promotion of the beneficial and shunning away the harmful elements in it."

For the 2D compressible isentropic Euler equations of polytropic gases with an initial perturbation of size $ {\varepsilon} $ of a rest state, it has been known that if the initial data are rotationnally invariant or irrotational, then the lifespan $ T_{{\varepsilon}} $ of the classical solutions is of order $ O(\frac {1}{{\varepsilon}^2}) $; if the initial vorticity is of size $ {\varepsilon}^{1+{\alpha}} $ ($ 0\le{\alpha}\le 1 $), then $ T_{{\varepsilon}} $ is of $ O(\frac {1}{{\varepsilon}^{1+{\alpha}}}) $. In the present paper, for the 2D compressible isentropic Euler equations of Chaplygin gases, if the initial data are a perturbation of size $ {\varepsilon} $, and the initial vorticity is of any size $ {\delta} $ with $ 0<{\delta}\le {\varepsilon} $, we will establish the lifespan $ T_{{\delta}} = O(\frac {1}{{\delta}}) $. For examples, if $ {\delta} = e^{- \frac {1}{{\varepsilon}^2}} $ or $ {\delta} = e^{-e^{ \frac {1}{{\varepsilon}^2}}} $ are chosen, then $ T_{{\delta}} = O(e^{ \frac {1}{{\varepsilon}^2}}) $ or $ T_{{\delta}} = O(e^{e^{ \frac {1}{{\varepsilon}^2}}}) $ although the perturbations of the initial density and the divergence of the initial velocity are only of order $ O({\varepsilon}) $. Our main ingredients are: finding the first and second null condition structures in 2D compressible Euler equations of Chaplygin gases and looking for the good unknowns; establishing a new class of weighted space-time $ L^\infty $-$ L^\infty $ estimates for the solution itself and its gradients of 2D linear wave equations; introducing some suitably weighted energies and taking the $ L^p $ $ (1

Horizontal transposable element transfer (HTT) events have occurred among a large number of species and play important roles in the composition and evolution of eukaryotic genomes. HTTs are also regarded as effective forces in promoting genomic variation and biological innovation. In the present study, HTT events were identified and analyzed in seven sequenced species of Rosales using bioinformatics methods by comparing sequence conservation and [K.sub.a]/[K.sub.s] value of reverse transcriptase (RT) with 20 conserved genes, estimating the dating of HTTs, and analyzing the phylogenetic relationships. Seven HTT events involving long terminal repeat (LTR) retrotransposons, two HTTs between Morus notabilis and Ziziphus jujuba, and five between Malus domestica and Pyrus bretschneideri were identified. Further analysis revealed that these LTR retrotransposons had functional structures, and the copy insertion times were lower than the dating of HTTs, particularly in Mn.Zj.1 and Md.Pb.3. Altogether, the results demonstrate that LTR retrotransposons still have potential transposition activity in host genomes. These results indicate that HTT events are another strategy for exchanging genetic material among species and are important for the evolution of genomes. Key words: LTR retrotransposons, horizontal transfer, Rosales, phylogeny, transposition activity. Les transferts horizontaux d'éléments transposables (HTT) sont survenus chez un grand nombre d'espèces et jouent des rôles importants dans la composition et l'évolution des génomes chez les eucaryotes. Les HTT sont également considérés comme des forces efficaces promouvant la variation génomique et l'innovation biologique. Dans le présent travail, les HTT ont été identifiés et analysés chez sept espèces séquencées de Rosales à l'aide de méthodes bioinformatiques en comparant la conservation des séquences et le ratio [K.sub.a]/[K.sub.s] chez la transcriptase inverse avec 20 gènes conservés, en datant les HTT et en analysant les relations phylogénétiques. Sept HTT impliquant des rétrotransposons à LTR, deux entre le Morus notabilis et le Ziziphus jujuba et cinq entre le Malus domestica et le Pyrus bretschneideri, ont été identifiés. Des analyses plus détaillées ont révélé que ces rétrotransposons à LTR avaient des structures fonctionnelles et les dates d'insertion des copies étaient plus récentes que la datation des HTT, particulièrement chez Mn.Zj.1 et Md.Pb.3. Ensemble, ces résultats montrent que les rétrotransposons à LTR ont maintenu la capacité de transposer au sein des nouveaux génomes hôtes. Ces résultats indiquent que les HTT constituent une autre stratégie pour échanger du matériel génétique entre les espèces et qu'ils sont importants pour l'évolution des génomes. [Traduit par la Rédaction] Mots-clés: rétrotransposons à LTR, transfert horizontal, Rosales, phylogénie, activité de transposition., Introduction Transposable elements (TEs) are mobile genomic units with the ability to transpose in the host genomes (El Baidouri et al. 2014; Markova and Mason-Gamer 2015; Roulin et al. 2009). [...]