922 resultados para Astronomy, Ancient--Iran


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Organophosphonates are ancient molecules that contain the chemically stable C–P bond, which is considered a relic of the reducing atmosphere on primitive earth. Synthetic phosphonates now have a wide range of applications in the agricultural, chemical and pharmaceutical industries. However, the existence of C–P compounds as contemporary biogenic molecules was not discovered until 1959, with the identification of 2-aminoethylphosphonic acid in rumen protozoa. Here, we review advances in our understanding of the biochemistry and genetics of microbial phosphonate metabolism, and discuss the role of these compounds and of the organisms engaged in their turnover within the P cycle.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recensão do livro "Itineraria Sacra. Bracara Augusta Fidelis et Ancient

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tick-borne relapsing fever is an endemic disease in Iran, with most cases attributed to infection by B. persica, which is transmitted by Ornithodoros tholozani soft ticks. Here, we report spirochetemia in blood of a puppy residing in Tehran, Iran. The causative species was identified by use of highly discriminative IGS sequencing; the 489 bp IGS sequence obtained in our study showed 99% identity (100% coverage) when compared with Borrelia persica sequences derived from clinical cases or from Ornithodoros tholozani ticks. Our IGS sequence also showed 99% similarity over 414 bp (85% coverage) with a strain from a domestic dog, and 96% over 328 bp (69% coverage) with a strain from a domestic cat. Pet-keeping in cosmopolitan cities like Tehran has become increasingly popular in recent years. Animals are often transported into the city in cages or cardboard boxes that might also harbour minute tick larvae and/or early stages of the nymphs bringing them into the urban environment. This may pose a threat to household members who buy and keep these puppies and as a result may come into close contact with infected ticks.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tese de doutoramento, Física, Universidade de Lisboa, Faculdade de Ciências, 2013

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Traduction d'Alexander Wylie (1815-1887), rédigée par Li Shan lan. Préface anglaise de Wylie, écrite à Shang hai (décembre 1859), suivie d'une note relative à la publication des Chinois 4885 et 4886. Vocabulaire de termes techniques. Préface Chinoise de Wylie (1859). Texte et figures ; les planches hors texte sont tirées sur papier européen. Imprimé en caractères mobiles, dans la maison Mo hai.18 livres.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The formation of the Sar Cheshmeh porphyry Cu-Mo deposit is related to the culmination of calc-alkaline igneous activity in the Kerman region. The deposit comprises a suite of Late Cenozoic intrusive sub-volcanic and extrusive rocks emplaced into a folded series of Eocene andesitic lavas and pyroclastic sediments. The earliest stage of magmatism was emplacement of a large granodiorite stock about 29 m.y.b.p. This was followed by intrusion of two separate porphyritic bodies at 15 (Sar Cheshrneh porphyry) and 12 m.y.b.p. (Late porphyry) and a series of sub-volcanic dikes between 12 and 9 m.y.b.p. Magmatic activity terminated with multi-phase extrusion of a Pelean dacitic dome complex between 10 and 2.8 m.y.b.p. The country rocks and the earlier porphyritic intrusions are pervasively altered to biotite-rich potassium silicate (metasomatic and hydrothermal) sericite-clay, phyllic and chlorite-clay, argillic assemblages. These grade outwards to an extensive propylitic zone. Within the ore body, the later intra-. and post-mineral dikes only reach the propylitic grade. At least three different sets of quartz veins are present, including a sericite-chlorite-quartz set which locally retrogrades pervasive secondary biotite to sericite. In the hypogene zone, metasomatic and hydrothermal alteration is related to all stages of magmatism but copper mineralization and veining are restricted to a period of 15 to 9 m.y.b.p.related to the early intrusive phases. The copper mineralization and silicate alteration do not fit a simple annular ring model but have been greatly modified by, 1. The existence of an ititial, outer ring, of metasomatic alteration overprinted by an inner.ring of hydrothermal alteration and, 2. later extensive dilating effects of intra- and post-mineral dikes. The hydrothermal clay mineral assemblage in the hypogene zone is illite-chlorite-kaolinite-smectite (beidellite). Preliminary studies indicate that the amount of each of these clays varies vertically and that hydrothermal zonation of clay minerals is possible. However, these minerals alter to illite-kaolinite assemblages in the supergene sulfide zone and to more kaolinite-rich assemblages in the supergene leached zone. Hydrothermal biotite breaks down readily in the supergene zone and is not well preserved in surface outcrops. The distribution of copper minerals in the supergene sulfide enrichment zone is only partly related to rock type being more dependent on topography and the availability of fractures.