The establishment of distinct cellular identities was pivotal during the evolution of Metazoa, enabling the emergence of an array of specialized tissues with different functions. In most animals including vertebrates, cell specialization occurs in response to a combination of intrinsic (e.g., cellular ontogeny) and extrinsic (e.g., local environment) factors that drive the acquisition of unique characteristics at the single‐cell level. The first functional organ system to form in vertebrates is the cardiovascular system, which is lined by a network of endothelial (...) cells whose organ‐specific characteristics have long been recognized. Recent genetic analyses at the single‐cell level have revealed that heterogeneity exists not only at the organ level but also between neighboring endothelial cells. Thus, how endothelial heterogeneity is established has become a key question in vascular biology. Drawing upon evidence from multiple organ systems, here we will discuss the role that lineage history may play in establishing endothelial heterogeneity. (shrink)

In this paper, the authors have detected a new effect in the area of geomagnetism, related to the behavior of a magnetic dipole freely floating on water surface. An experiment is described in the present paper in which a magnetic dipole fixed upon a float placed on non- magnetized water surface undergoes displacement along with reorientation caused by fine structure of the earth's magnetic field. This fact can probably be explained by secular decrease of the earth's major dipole moment. Further, (...) a detailed study of the phenomenon may create interesting premises for its practical use, particularly for the analysis of fine structure of geomagnetic field and its time-dependent anomalies. A strange behavior of some sea fish species prior to strong earthquakes may be explained if the fish are assumed as 'live magnetic dipoles'. (shrink)

Traditionally the domain of scientists, the history of science became an independent field of inquiry only in the twentieth century and mostly after the Second World War. This process of emancipation was accompanied by a historiographical departure from previous, 'scientistic' practices, a transformation often attributed to influences from sociology, philosophy and history. Similarly, the liberal humanists who controlled the Cambridge History of Science Committee after 1945 emphasized that their contribution lay in the special expertise they, as trained historians, brought to (...) the venture. However, the scientists who had founded the Committee in the 1930s had already advocated a sophisticated contextual approach: innovation in the history of science thus clearly came also from within the ranks of scientists who practised in the field. Moreover, unlike their scientist predecessors on the Cambridge Committee, the liberal humanists supported a positivistic protocol that has since been criticized for its failure to properly contextualize early modern science. Lastly, while celebrating the rise of modern science as an international achievement, the liberal humanists also emphasized the peculiar Englishness of the phenomenon. In this respect, too, their outlook had much in common with the practices from which they attempted to distance their project. (shrink)

Teoría de la educación/J.García Carrasco.-v.1.

Study of Dvādaśāranayacakra, work by Mallavādikṣamāśramaṇa, 5th cent., on the metaphysical doctrine of partial manifestation (naya) according to the Śvetāmbara Jainism.

Encyclopedic dictionary of Yogasūtra of Patañjali.

At Pliny, Ep. 5. 18 we read that Macer, the recipient of that letter, has a villa which Pliny says must be lovely, because in qua [sc. villa] se composuerat homo felicior, antequam felicissimus fieret. The identity of this homo felicior is undoubtedly of some interest, but the latest commentary on Pliny's Letters has nothing to say on the matter. However, B. Radice in her two translations of the Letters says that the person in question is Nerva, but adds as (...) a second possibility ‘the dictator Sulla’. In this ambivalence she is at one with many of the older commentators on the Letters. Alone among the commentators examined by us, M. Gesner elects to give preference to Sulla over Nerva. We believe Sulla is certainly the owner in question, but since the ambiguity persists in the scholarly tradition, a fresh look should be taken at the problem and the case against Nerva and for Sulla be put more fully than hitherto. In using the phrase homo felicior, antequam felicissimus fieret without actually naming the person, it is clear that Pliny takes it for granted that the individual in question will be immediately recognizable to Macer, the recipient of the letter, by this description. It follows, therefore, that the phrase had become well established as a commonplace, inevitably and unambiguously linked to one person only. All of our evidence suggests that it cannot be applied to Nerva. First of all it is likely that such a phrase would need time to become accepted into the tradition so as to become readily identifiable, whereas Pliny was writing only a relatively short time after Nerva's reign. (shrink)