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151.
Duyilemi C. Ajonijebu Oualid Abboussi Vivienne A. Russell Musa V. Mabandla William M. U. Daniels 《Cellular and molecular life sciences : CMLS》2017,74(15):2735-2747
The detrimental effects of drug abuse are apparently not limited to individuals but may also impact the vulnerability of their progenies to develop addictive behaviours. Epigenetic signatures, early life experience and environmental factors, converge to influence gene expression patterns in addiction phenotypes and consequently may serve as mediators of behavioural trait transmission between generations. The majority of studies investigating the role of epigenetics in addiction do not consider the influence of social interactions. This shortcoming in current experimental approaches necessitates developing social models that reflect the addictive behaviour in a free-living social environment. Furthermore, this review also reports on the advancement of interventions for drug addiction and takes into account the emerging roles of histone deacetylase (HDAC) inhibitors in the etiology of drug addiction and that HDAC may be a potential therapeutic target at nucleosomal level to improve treatment outcomes. 相似文献
152.
153.
In this paper a multivariate time series model using the seemingly unrelated time series equation (SUTSE) framework is proposed to forecast longevity gains. The proposed model is represented in state space form and uses Kalman filtering to estimate the unobservable components and fixed parameters. We apply the model both to male mortality rates in Portugal and the USA. Our results compare favorably, in terms of mean absolute percentage error, in‐sample and out‐of‐sample, to those obtained by the Lee–Carter method and some of its extensions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
154.
155.
C. N. Brown 《Annals of science》2013,70(1):28-74
Diffraction gratings have contributed enormously to modern science. Although some historians have written about them, there is much more to be brought to light. This paper discusses their development and use in the period up to about 1880 before Rowland began to produce them. Rittenhouse described the action of a diffraction grating in 1786, but no explanation was possible until the wave theory of light was developed. Fraunhofer discovered the dark lines in the solar spectrum in 1814, and then investigated diffraction, producing the first ruled gratings, making detailed measurements and calculating the wavelengths of prominent spectral lines. After Bunsen and Kirchhoff showed the association between spectral lines and chemical elements there was an upsurge of interest in measuring wavelengths. The gratings used in this work almost all came from one source, a relatively unknown instrument maker called Nobert, who made them by an extremely laborious process using a machine he had built himself. The most significant wavelength measurements were made by Ångström, but Mascart, Van der Willigen, Stefan, Ditscheiner and Cornu also did important work. Nobert gratings were investigated by Quincke, copied photographically by Rayleigh, and were known and discussed in the USA. Nobert's work helped to advance spectroscopy much more than has been acknowledged. 相似文献
156.
W.E. Knowles Middleton D.Sc. F.R.S.C. 《Annals of science》2013,70(2):125-141
In 1639–1640 Benedetto Castelli (1577–1643) wrote a treatise on the loadstone which is quite unlike any of its contemporaries. In it are the origins of the notion of elementary magnets sharing a common alignment, the idea that all materials are magnetic in different ways, and the first intimation of the conception of magnetic domains. Castelli did not publish his treatise. Nevertheless his work was noted during his life-time, and may have exerted an influence on the development of magnetic theory in the 17th century. The treatise was published in 1883. Since then, however, it has either been neglected or not appreciated. It deserves being rescued from the neglect of more than three centuries. 相似文献
157.
K.J. Franklin D.M. F.R.C.P. 《Annals of science》2013,70(3):203-228
We present an analysis, and first full English translation, of a paper by Kant entitled ‘Über die Vulcane im Monde’ (1785). Kant became interested in the question of whether the mountains of the Moon were extinct volcanoes. Stimulated by the work of Herschel, Aepinus, and others, he considered the appearance of the Moon's surface and the possibility of lunar vulcanism. From this, he was led to consider the structures of mountain ranges on the Earth, which he decided were non-volcanic in origin, being produced by eruptions of vapours from the interior of the Earth soon after it formed from an original ‘chaos’. Kant developed his ideas in such a way as to yield a characteristic eighteenth-century ‘theory of the Earth’. We argue that the empirical base of his theory was provided by knowledge of the mountain ranges of Bohemia and Moravia. Analogies based on observations of the Moon further assisted in the construction of the theory. But the reasoning ran in two directions: what was seen on the Moon was construed in terms of what Kant knew of the Earth's topography; and the Earth's topography was presumed to be analogous to that of the Moon, for both the Earth and the Moon (and indeed all heavenly bodies) supposedly had essentially similar origins. Kant's ideas of 1785 are related to his earlier writings of 1754, 1755, and 1756, and also to the lectures on physical geography that he presented at Königsberg. 相似文献
158.
As the most famous woman scientist of the twentieth century, there has been no shortage of books and articles on the life and career of Marie Curie (1867–1934). Her role as a director of a laboratory-based research school in the new scientific field of radioactivity, a field which embraced both chemistry and physics, however, has never been examined. In recent years, there has been a growing interest in the question of research schools, and Morrell, Ravetz, Geison, and Klosterman, amongst others, have written on this subject. Using, in part, the methodology of Morrell, this paper investigates the role of Marie Curie as a school director in the Paris Faculty in the years 1907–14, examining the work and characteristics of her school and assessing her effectiveness as a director. 相似文献
159.
SongTing Shi David J. J. de Gorter Willem M. H. Hoogaars Peter A. C. ’t Hoen Peter ten Dijke 《Cellular and molecular life sciences : CMLS》2013,70(3):407-423
Bone morphogenetic proteins (BMPs) are important extracellular cytokines that play critical roles in embryogenesis and tissue homeostasis. BMPs signal via transmembrane type I and type II serine/threonine kinase receptors and intracellular Smad effector proteins. BMP signaling is precisely regulated and perturbation of BMP signaling is connected to multiple diseases, including musculoskeletal diseases. In this review, we will summarize the recent progress in elucidation of BMP signal transduction, how overactive BMP signaling is involved in the pathogenesis of heterotopic ossification and Duchenne muscular dystrophy, and discuss possible therapeutic strategies for treatment of these diseases. 相似文献
160.
Martha M. Muñoz Kristen E. Crandell Shane C. Campbell-Staton Kristi Fenstermacher Hannah K. Frank Paul Van Middlesworth 《Journal of Natural History》2015,49(27-28):1717-1730
Aquatic anoles present an interesting ecomorphological puzzle. On the one hand, the link between habitat use and morphology is well established as convergent within the Caribbean anole radiation. On the other hand, aquatic anoles do not appear to form an ecomorphological group – rather, it appears that there may be several ways to adapt to aquatic habitats. We explore this issue by examining the ecology, morphology and performance of four species of Central American aquatic anoles belonging to two different lineages. Overall, we find that aquatic anoles overlap in multiple ecological and morphological dimensions. However, we do find some differences in substrate use, claw and limb morphology, and bite force that distinguish Anolis aquaticus from the other three species (A. lionotus, A. oxylophus and A. poecilopus). Our results suggest that A. aquaticus is adapted to climb on boulders, whereas the other species utilise vegetation in streamside habitats. 相似文献