Guido von Arezzo. Sein Leben und Wirken. Aus Veranlassung und mit besonderer Rücksicht auf eine Dissertation: Sopra la vita, le opere ed il sapere di Guido d'Arezzo, von Luigi Angeloni. Nebst einem Anhange über die dem heiligen Bernhard zugeschriebenen musikalischen Tractate.

Bibliographical footnotes.

La poesia giovanile e La canzone d'amore di Guido Cavalcanti;

Mode of access: Internet.

Die englische Legation des Cardinals Guido Fulcodi, des spaeteren P. Clemens IV.

Thesis (doctoral)--Universitat Breslau.

Benthic foraminifera groups of ODP Site 162-982

The pulsed decline and eventual extinction of 51 species of elongate, cylindrical deep-sea benthic foraminifera (Stilostomellidae, Pleurostomellidae, and some Nodosariidae) occurred at intermediate water depths (1145-2168 m, Sites 980 and 982) in the northern North Atlantic during the mid-Pleistocene transition (MPT, 1.2-0.6 Ma). In the early Pleistocene, prior to their disappearance, these species comprised up to 20% of the total abundance of the benthic foraminiferal assemblage at 2168 m, but up to only 2% at 1145 m. The MPT extinction of 51 species represents ?20% of the total benthic foraminiferal diversity at bathyal depths in the North Atlantic (excluding the myriad of small unilocular forms). The extinction rate during the MPT was approximately 10 species per 0.1 myr, being one or two orders of magnitude greater than normal background turnover rates of deep-sea benthic foraminifera. Comparison of the precise timings of declines and disappearances (= highest occurrences) of each species shows that they were often diachronous between the two depths. The last of these species to disappear in the North Atlantic was Pleurostomella alternans at ~0.679 and ~0.694 Ma in Sites 980 and 982, respectively, which is in good agreement with the previously documented global "Stilostomella extinction" datum within the period 0.7-0.58 Ma. Comparison with similar studies in intermediate depth waters in the Southwest Pacific Gateway indicates that ~61% of the extinct species were common to both regions, and that although the pattern of pulsed decline was similar, the precise order and timing of the extinction of individual species were mostly different on opposite sides of the world. Previous studies have indicated that this extinct group of elongate, cylindrical foraminifera lived infaunally and had their greatest abundances in poorly ventilated, lower oxygen environments. This is supported by our study where there is a strong positive correlation (r = ~+ 0.8) between the flux of the extinction group and low-oxygen/high organic input species (such as Uvigerina, Bulimina and Bolivina) during the MPT, suggesting a close relationship with lower oxygen levels and high food supply to the sea floor. The absolute abundance, flux, and number of the extinction group of species show a progressive withdrawal pattern with major decreases occurring in cold periods with high d13C values. This might be related to increasing chemical ventilation of glacial intermediate water.

Calcareous nannofossils and C37 alkenones at ODP Site 162-982

During the late Pliocene (~3 to 2.5 Ma), oceanic records of opal and C37 alkenone accumulation from around the world show a secular shift towards lower values in the high latitudes and higher values in the low and mid latitudes. These shifts are broadly coincident with the intensification of northern hemisphere glaciation and are suggestive of changes in export productivity, with potential implications for Pliocene atmospheric carbon dioxide concentrations. The interpretation of a global latitudinal shift in productivity, however, requires testing because of the potential uncertainties associated with site to site comparisons of records that can be influenced by highly nonlinear processes associated with production, export, and preservation. Here, we assess the inferred Pliocene latitudinal productivity shift interpretation by presenting new records of C37 alkenone accumulation from Ocean Drilling Program (ODP) Site 982 in the North Atlantic and biotic assemblages (calcareous nannoplankton) from this site and ODP Site 846 in the eastern tropical Pacific. Our results corroborate the interpretation of C37 alkenone accumulation as a proxy for gross export productivity at these sites, indicating that large-scale productivity decreases at high latitudes and increases at tropical sites are recorded robustly. We conclude that the intensification of northern hemisphere glaciation during the late Pliocene was associated with a profound reorganisation of ocean biogeochemistry.

Guido Bonato y "El Tratado de Forlivio sobre los más principales juicios de los astros"

En esta tesis doctoral pretendo aproximarme a la figura del famoso astrólogo Guido Bonato o Bonatus, así como a su obra, el Tratado de Forlivio sobre los más principales juicios de los astros, traducción castellana llevada a cabo por Auger Ferrer en el siglo XVII (1638) del voluminoso compendio latino Registrum Guidonis Bonati de Forliuio. Decem continens tractatus Astronomie (1491). Así pues, es mi intención, en primera instancia, hacer una extensa introducción a la Historia de la Astrología desde la Antigüedad hasta el Renacimiento, contexto este último en el cual se inscribe el autor de la traducción castellana de la obra del autor latino Bonatus. Me centraré, con especial atención, en los avatares científico-teológicoastrológicos del siglo XIII, siglo en el cual el astrólogo ejerce su labor intelectual. En segundo lugar, pretendo dedicar un espacio a la vida de Guido Bonato, dando una serie de detalles y apuntes biográficos. Asimismo, he de hablar de su extensa producción astrológica en la tercera parte: el Liber astronomicus, posteriormente nombrado como Registrum Guidonis Bonati de Forliuio (1491), Decem continens tractatus astronomie (1506) y De astronomia tractatus decem (1550). En cuarto lugar, intentaré introducir al lector al significado de la extensa y compleja obra latina del astrólogo nativo de Forlí. Por último, destinaré a la quinta y última parte de este trabajo el análisis pormenorizado del Tratado de Forlivio sobre los más principales juicios de los astros. Nuestra obra se adhiere a la corriente de la llamada astrología judiciaria, concretamente a la llamada astrología de interrogaciones o astrología horaria, que predomina en las obras de los astrólogos árabes medievales, según afirma Luis Miguel Vicente García en su obra Estrellas y astrólogos en la literatura medieval española1. De hecho, la parte original latina se intitula «De interrogationibus», «Tractatus interrogationibus seu questioniis guidonis bonati» o «Tractatus super precipuis iudiciis astrorum»...