5 research outputs found
Oceanographic and climatic consequences of the tectonic evolution of the southern scotia sea basins, Antarctica
The Scotia Sea is a complex geological area located in the Southern Ocean which evolution is closely linked to the opening of the Drake Passage. Structural highs of continental nature derived from the former continental bridge between South America and the Antarctic Peninsula surround the abyssal plains of the Scotia Sea, restricting small isolated sedimentary basins along its southern margin. Morpho-structural and seismo-stratigraphic analyses of multichannel seismic reflection profiles, and additional geophysical data available in the region, have been conducted, decoding regional and global implications of the basins' evolution. The main aim of this work is to describe the stratigraphic evolution of the southern Scotia Sea basins, from their opening in the back-arc tectonic context of the Scotia Sea, to the last oceanographic changes which have carried on global climatic implications. The evolution of the south Scotia Sea occurred through two major tectonic stages registered in the sedimentary record of the region: 1) the end of the subduction in the northwest part of the Weddell Sea during the early Miocene, which shortened the back-arc subduction trench generating a major change in the regional tectonic field that determined the evolution of the southern basins towards two different types of passive margins: magma-poor and magma-rich; and 2) the full development of the southern Scotia Sea basins during the middle Miocene, that led to the opening of deep oceanic gateways along the South Scotia Ridge. Interplay among tectonics, oceanography and climate is proposed to control the regional sedimentary stacking pattern, with coeval changes globally identified
Cassava-based (Manihot esculenta Crantz) fermented energy-protein food for bovines
Cassava (Manihot esculenta Crantz) is a tuber that is used for human consumption and in the diet of animals, it is characterized by having a high starch content and low protein content. In this sense, it is proposed to use solid state fermentation (FES) to obtain a fermented feed based on cassava with a high energy-protein value for cattle. The objective of this work was to evaluate the effect of the levels of yeast inoculum (IL) and days of fermentation, in the chemical, fermentative and microbiological composition of fermented foods based on cassava. A completely randomized design was used with factorial arrangement, 3 levels of yeast inoculum (0, 5 and 10%) and 5 days of fermentation (0, 1, 2, 3 and 4 days). Interaction was found between the factors studied in the variables pH and crude protein (CP). The highest pH values ??were obtained with the addition of 10% of the IL (8.67) and values ??of 16.55% of PC were found. In relation to true protein (PV) and in situ degradation of dry matter (DIMS), no differences were found in the inoculum level or the days of fermentation studied, the PV values ??were 8% and DIMS 80 %. The yeast inoculum and the days of fermentation did not increase the true protein of the fermented cassava-based food.L
Objective: To assess the effect of different yeast levels and fermentation times on the chemical, fermentative, and microbiological composition of cassava in order to produce a cassava-based fermented food.
Design/Methodology/Approach: We used a completely randomized design with a factorial arrangement, three yeast inoculum levels (0, 5, and 10%), and five fermentation times (0, 1, 2, 3, and 4 days).
Results: We found significant interaction of the studied factors with the pH and crude protein (CP) variables. The highest pH values were obtained adding 10% yeast inoculum (YI) (8.67). CP values of 16.55% were found. No differences caused by the studied inoculum levels and fermentation times were found in true protein (TP) and the in situ degradation of dry matter (IDDM). TP and IDDM had 8% and 80% values, respectively.
Study Limitations/Implications: A behavior test with bovines must be conducted to demonstrate the potential of cassava-based fermented foods in meat and/or milk production.
Findings/Conclusions: The yeast inoculum and the fermentation days did not increase the TP in the cassava-based fermented food
Topo-Iberia project: CGPS crustal velocity field in the Iberian Peninsula and Morocco
A new continuous GPS network was installed under the umbrella of a research project called "Geociencias en Iberia: Estudios integrados de topografĂa y evoluciĂłn 4D (Topo-Iberia)", to improve understanding of kinematic behavior of the Iberian Peninsula region. Here we present a velocity field based on the analysis of the 4 years of data from 25 stations constituting the network, which were analyzed by three different analysis groups contributing to the project. Different geodetic software packages (GIPSY-OASIS, Bernese and GAMIT) as well as different approaches were used to estimate rates of present day crustal deformation in the Iberian Peninsula and Morocco. In order to ensure the consistency of the velocity fields determined by the three groups, the velocities obtained by each analysis center were transformed into a common Eurasia Reference Frame. After that, the strain rate field was calculated. The results put in evidence more prominent residual motions in Morocco and southernmost part of the Iberian Peninsula. In particular, the dilatation and shear strain rates reach their maximum values in the Central Betics and northern Alboran Sea. A small region of high shear strain rate is observed in the east-central part of the peninsula and another deformation focus is located around the Strait of Gibraltar and the Gulf of Cadiz