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2.
Ambix ; 61(4): 327-44, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25509633

RESUMO

This essay challenges the often expressed view that the principles of metals, namely mercury and sulphur, were generally viewed by alchemists as being of a 'metaphysical' character that made them inaccessible to the tools and operations of the laboratory. By examining a number of Arabo-Latin and Latin alchemical texts in circulation before the end of the thirteenth century, the author presents evidence that most alchemists of the period considered mercury and sulphur to be materials subject to techniques of purification in the same way that naturally occurring salts and minerals could be freed of their impurities or dross. The article also points to the immense influence of Avicenna and Albertus Magnus in formulating the theory that mercury and sulphur were compounds of different materials, containing both fixed and unfixed components. Finally, the author briefly examines the relationship between this materialist approach to the principles and the chymical atomism of early modern authors who were deeply aware of medieval alchemical literature.


Assuntos
Alquimia , Manuscritos como Assunto/história , Mercúrio/história , Enxofre/história , Química/história , Europa (Continente) , História Medieval , Mercúrio/química , Pérsia , Enxofre/química
3.
Osiris ; 29: 35-48, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26103746

RESUMO

The Sarepta, oder Bergpostill (1562) by Johann Mathesius is a book of sermons on mining and mineral subjects in which the composition and generation of metals in ore veins are discussed in terms of the sulfur-mercurius theory. Gur was an embodiment of mercurius or of sulfur and mercurius. Sulfur was evident in the sulfurous odor of the mines, in the supposed effects of subterranean heat, and in the deposition of mineral sulfur during the roasting of the ores. The toxic smoke given off during smelting was considered to be an additional manifestation of mercurius. Mathesius's sermons offer a glimpse of the ways miners' understanding of ores overlapped with alchemists' theories.


Assuntos
Alquimia , Mercúrio/história , Mineração/história , Enxofre/história , República Tcheca , História do Século XVI , Mercúrio/química , Prata , Enxofre/química
4.
Protein Cell ; 1(1): 14-21, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21203994

RESUMO

Here we tell a 20-year long story. It began with an easily overlooked DNA degradation (Dnd) phenomenon during electrophoresis and eventually led to the discovery of an unprecedented DNA sulfur modification governed by five dnd genes. This unusual DNA modification, called phosphorothioation, is the first physiological modification identified on the DNA backbone, in which the nonbridging oxygen is replaced by sulfur in a sequence selective and stereo-specific manner. Homologous dnd gene clusters have been identified in diverse and distantly related bacteria and thus have drawn immediate attention of the entire microbial scientific community. Here, we summarize the progress in chemical, genetic, enzymatic, bioinformatical and analytical aspects of this novel postreplicative DNA modification. We also discuss perspectives on the physiological functions of the DNA phosphorothioate modification in bacteria and their implications.


Assuntos
Bactérias/metabolismo , DNA Bacteriano/metabolismo , Enxofre/metabolismo , Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/história , Genes Bacterianos , História do Século XX , História do Século XXI , Família Multigênica , Streptomyces lividans/genética , Streptomyces lividans/metabolismo , Enxofre/química , Enxofre/história
6.
Med Secoli ; 19(2): 609-26, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18450038

RESUMO

In Sicily the sulphur extraction represented an occasion of economic growth and a development for the dignity of the workers. The "carusi", young boys from 6 to 14 years old, were given up by their parents in return of a hardly payed of loan; it was the so called "soccorso morto" (dead aid). They were submitted to an enormous very hard physical work that caused severe damage to the skeleton and this was the reason of their inability to military service. The anthropometric surveys of "carusi" and pupils highlight for the first ones a reduced increase of the height and for the second ones the presence of "gibbo". For this reasons the inhabitans of Racalmuto were called racalmutesi immiruti" which means that people who lives in Racalmuto were hunchbacked. Nowadays it's possible to say that dietary and nutritional causes determined metabolic damages to the skeleton. A comparison between people who have been declared unable for military service belonged to the two lower clones of farmers and miners showed a lower incidence of the first ones. The law of 1866 on child labour assigned to medical doctors the task of certifying their suitability to work: the first step of normalisation on a medical care basis.


Assuntos
Emprego/história , Mineração/história , Doenças Profissionais/história , Adolescente , Osso e Ossos/patologia , Criança , Emprego/legislação & jurisprudência , História do Século XVIII , História do Século XIX , História do Século XX , Humanos , Itália , Masculino , Doenças Profissionais/patologia , Enxofre/história
11.
Isis ; 77(288): 487-97, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3533841
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