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Transits during oceanographic expeditions constitute a potential huge amount of acquired bathymetric data that could be systematically integrated to increase the knowledge on submarine morphology, especially for planned surveys in the equatorial Atlantic, the Arctic, the Indian and the Southern Oceans. The recent PNRA ISOBatA project aims to efficiently exploit seafloor datasets collected during transfer times within the Antarctic region and the Ross Sea. Along the route from New Zealand to the Italian Mario Zucchelli Station in the Ross Sea, the Emerald Fracture Zone and the Macquarie Triple Junction, located in the SW Pacific Ocean, represent two selected areas to test the strength of transit acquisition in remote areas, normally affected by adverse weather conditions. The ISOBatA project has the main purpose to contribute to the mapping of Antarctic waters developing best practices and dedicated workflows to implement QA in multibeam data acquisition procedures during transit times, as well as in the processing, analysis and archiving of data and metadata. The ISOBatA experience in the Southern Ocean suggests there are several critical issues associated with collection of multibeam data in remote and ice-infested waters. Operating procedures need more standardization, to avoid the acquisition of redundant data along common routes and unreliable data. Our work aims to open a discussion to address the need for standardization in data acquisition during transit times, which should include priority in accordance with the geomorphological/geographical nature of the working areas. The integration of bathymetric data acquired during research vessel transfers to remote regions could imply a common international effort for a systematic exploration of the seafloor, sharing coverage in real time to avoid redundancy.

The experience of the PNRA ISOBatA (Italian Southern Ocean Bathymetry from consistent exploitation of opportunistic seafloor datasets in Antarctic region and surrounding areas) project, over the past two years, has shown the importance of collecting underway bathymetric data by exploiting the transit time between the Italian Mario Zucchelli Station in the Ross Sea and New Zealand, during Antarctic expeditions. Mapping the Antarctic seafloor is a challenging goal in terms of critically advancing our knowledge of seabed morphology, especially when strategically coupled with field observations. High-resolution mapping of the Southern Ocean seafloor may offer valuable insights into tectonic and volcanic processes of plate boundaries in this remote environment. The ISOBatA project collected in particular underway bathymetric data on board the Italian R/V Laura Bassi at the Macquarie Triple Junction and crossing the Emerald Fracture Zone, where also magnetic data were obtained. From a methodological point of view, the ISOBatA project developed dedicated procedures to ensure robust multibeam data quality during the acquisition, processing and archiving phases, to also provide a data sharing policy according to FAIR principles. The expeditions in the Southern Ocean revealed critical problems mainly related to environmental conditions associated to the working area (i.e.: ice-populated waters and/or adverse weather conditions) but at the same time promoted the implementation of appropriate best practices and workflows, also defined according to the geomorphological context of the working sectors. Our main objective is to promote common and shared procedures for the management of multibeam bathymetric data acquisition during transit times, and to support the current scientific effort that all interested countries are undertaking to achieve a systematic exploration of the seafloor, especially for remote areas such as the Arctic, the Southern or the equatorial Atlantic Oceans.

Dove Basin, a small oceanic domain located within the southern Scotia Sea, evidences a complex tectonic evolution linked to the development of the Scotia Arc. The basin also straddles the junction between the main Southern Ocean water masses: the Antarctic Circumpolar Current (ACC), the Southeast Pacific Deep Water (SPDW) and the Weddell Sea Deep Water (WSDW). Analysis of multichannel seismic reflection profiles, together with swath bathymetry data, reveals the main structure and sediment distribution of the basin, allowing a reconstruction of the tectonostratigraphic evolution of the basin and assessment of the main bottom water flows that influenced its depositional development. Sediment dispersed in the basin was largely influenced by gravity‐driven transport from adjacent continental margins, later modified by deep bottom currents. Sediments derived from melting icebergs and extensive ice sheets also contributed to a fraction of the basin deposits. We identify four stages in the basin evolution which – based on regional age assumptions – took place during the early Miocene, middle Miocene, late Miocene–early Pliocene and late Pliocene–Quaternary. The onsets of the ACC flow in Dove Basin during the early Miocene, the WSDW flow during the middle Miocene, and the SPDW during the late Miocene were influenced by tectonic events that facilitated the opening of new oceanic gateways in the region. The analysis of Dove Basin reveals that tectonics is a primary factor influencing its sedimentary stacking patterns, the structural development of new oceanic gateways permitting the inception of deep‐water flows that have since controlled the sedimentary processes.

Dove Basin, a small oceanic domain located within the southern Scotia Sea, evidences a complex tectonic evolution linked to the development of the Scotia Arc. The basin also straddles the junction between the main Southern Ocean water masses: the Antarctic Circumpolar Current (ACC), the Southeast Pacific Deep Water (SPDW) and the Weddell Sea Deep Water (WSDW). Analysis of multichannel seismic reflection profiles, together with swath bathymetry data, reveals the main structure and sediment distribution of the basin, allowing a reconstruction of the tectonostratigraphic evolution of the basin and assessment of the main bottom water flows that influenced its depositional development. Sediment dispersed in the basin was largely influenced by gravity‐driven transport from adjacent continental margins, later modified by deep bottom currents. Sediments derived from melting icebergs and extensive ice sheets also contributed to a fraction of the basin deposits. We identify four stages in the basin evolution which – based on regional age assumptions – took place during the early Miocene, middle Miocene, late Miocene–early Pliocene and late Pliocene–Quaternary. The onsets of the ACC flow in Dove Basin during the early Miocene, the WSDW flow during the middle Miocene, and the SPDW during the late Miocene were influenced by tectonic events that facilitated the opening of new oceanic gateways in the region. The analysis of Dove Basin reveals that tectonics is a primary factor influencing its sedimentary stacking patterns, the structural development of new oceanic gateways permitting the inception of deep‐water flows that have since controlled the sedimentary processes.

The DRAKE-SCOTIA SEA GATEWAYS is a new multidisciplinary International Ocean Discovery Program (IODP) drilling proposal aimed at determining the time of opening and pattern of development of gateways in the Drake Passage and the adjacent Scotia Sea, and their influence on global ocean circulation, biotic evolution and climate. The Drake Passage with the adjacent Scotia Sea represent one of Earth’s most important oceanic gateways, between the southern tip of South America and the Antarctic Peninsula, a crucial area for water mass exchange between the Pacific Ocean, the Atlantic Ocean and the Weddell Sea, the importance of which is evidence by in many multinational studies. Nevertheless, the region has not been yet drilled for scientific purposes. The objective of this work is to present the main scientific goals of this drilling proposal and its link with the IODP Science Plan for 2013-2023

The DRAKE-SCOTIA SEA GATEWAYS is a new multidisciplinary International Ocean Discovery Program (IODP) drilling proposal aimed at determining the time of opening and pattern of development of gateways in the Drake Passage and the adjacent Scotia Sea, and their influence on global ocean circulation, biotic evolution and climate. The Drake Passage with the adjacent Scotia Sea represent one of Earth’s most important oceanic gateways, between the southern tip of South America and the Antarctic Peninsula, a crucial area for water mass exchange between the Pacific Ocean, the Atlantic Ocean and the Weddell Sea, the importance of which is evidence by in many multinational studies. Nevertheless, the region has not been yet drilled for scientific purposes. The objective of this work is to present the main scientific goals of this drilling proposal and its link with the IODP Science Plan for 2013-2023.

The DRAKE-SCOTIA SEA GATEWAYS is a new multidisciplinary International Ocean Discovery Program (IODP) drilling proposal aimed at determining the time of opening and pattern of development of gateways in the Drake Passage and the adjacent Scotia Sea, and their influence on global ocean circulation, biotic evolution and climate. The Drake Passage with the adjacent Scotia Sea represent one of Earth’s most important oceanic gateways, between the southern tip of South America and the Antarctic Peninsula, a crucial area for water mass exchange between the Pacific Ocean, the Atlantic Ocean and the Weddell Sea, the importance of which is evidence by in many multinational studies. Nevertheless, the region has not been yet drilled for scientific purposes. The objective of this work is to present the main scientific goals of this drilling proposal and its link with the IODP Science Plan for 2013-2023.

The DRAKE-SCOTIA SEA GATEWAYS is a new multidisciplinary International Ocean Discovery Program (IODP) drilling proposal aimed at determining the time of opening and pattern of development of gateways in the Drake Passage and the adjacent Scotia Sea, and their influence on global ocean circulation, biotic evolution and climate. The Drake Passage with the adjacent Scotia Sea represent one of Earth’s most important oceanic gateways, between the southern tip of South America and the Antarctic Peninsula, a crucial area for water mass exchange between the Pacific Ocean, the Atlantic Ocean and the Weddell Sea, the importance of which is evidence by in many multinational studies. Nevertheless, the region has not been yet drilled for scientific purposes. The objective of this work is to present the main scientific goals of this drilling proposal and its link with the IODP Science Plan for 2013-2023

English: It has previously been implicated in literature that intracellular gas bubbles cannot form in yeast cells even under high gas supersaturation conditions. Furthermore, not even protein-coated gas vesicles found in Cyanobacteria are expected in yeasts. The lack of intracellular gas bubbles has been attributed to the increased structuring of water and lack of water with nucleation properties. This, however, is considered a missing link since yeasts, the workhorses of the baking and brewing industry, are known to produce and vigorously release carbon dioxide (CO2) gas during fermentation. Here we resolve the missing link between CO2 production by glycolysis and the eventual release of CO2 from the cells, and show that yeasts are capable of producing intracellular gas bubbles which were found to occupy a significant part of the cell. These gas bubbles do not contain a membrane that surrounds them. Furthermore, addition of zinc to the growth medium resulted in the “galvanization” of the bubbles suggesting that the gas bubbles may possibly contain CO2. These findings should pave way for future research on CO2 behaviour under pressurized conditions that may have an impact on fermentation biotechnology. Furthermore we show that these intracellular gas bubbles deform cell organelles such as the nucleus. The skin surrounding the gas bubbles is able to withstand tension as they do not disintegrate when they come in contact with organelle membranes. Further research should now be performed on the mechanical effects of the gas bubbles on metabolic and coding functions of yeasts as gas bubbles deform and contort cell organelles. From these findings careful consideration is required during optimization of fermentation parameters to prevent CO2 toxicity effects on fermentation performance and flavor formation in practical brewing., Afrikaans: Volgens literatuur, kan intrasellulêre gasborrels nie in gisselle gevorm word nie, selfs nie onder hoë gassupersaturasie nie. Verder word selfs nie eens proteïenomhulde gasvesikels wat in Cyanobakterieë voorkom verwag in gisselle nie. Die afwesigheid van intrasellulêre gasborrels was toegeskryf aan die verhoogde strukturering van water en tekort aan water met kernvormingseienskappe. Die afwesigheid van gasborrels word as „n raaisel beskou aangesien giste, die werkesels van die bak en bierbrou industrieë, bekend is vir die vrystelling van groot hoeveelhede koolstofdioksied (CO2) tydens fermentasie. In hierdie stuk verklaar ons die raaisel aangaande die produksie van CO2 deur glikolise en die uiteindelike vrystelling van CO2 vanuit die selle en wys ons dat giste oor die vermoë beskik om intrasellulêre gasborrels to vorm wat „n groot deel van die selvolume uitmaak. Hierdie gasborrels het geen membraanomhulsel nie. Wanneer sink by die groeimedium gevoeg word vind daar “galvanisering” van die borrels plaas wat impliseer dat hierdie gasborrels CO2 bevat. Hierdie resultate behoort die weg te baan vir toekomstige navorsing rakende die optrede van CO2 onder druk en dit mag moontlik „n impak hê op biotegnologiese fermentasies. Verder wys ons ook dat hierdie borrels die selorganelle, soos onder andere die kern, vervorm. Die “vel” rondom die gasborrels kan drukking weerstaan en dus disintergreer die borrels nie wanneer dit in kontak kom met die organelmembraan nie. Verdere navorsing moet nou volg om die meganiese effek van die gasborrels op die metaboliese en koderingsfunksies van die gisselle te bepaal aangesien die borrels die organelle vervorm. Na aanleiding van hierdie resultate moet die vorming van gasborrels in ag geneem word tydens die optimisering van fermentasie parameters om CO2 toksisiteit te voorkom.

A complete Bouguer gravity map of the central-eastern part of the Isla Grande de Tierra del Fuego, and a general bathymetric chart of the Lago Fagnano have been realized, on the basis of a series of field geophysical surveys carried out on the Island since 1998. The regional gravity anomaly trend onshore shows a progressive negative gradient from N to S. Distinct, broadly E-W-trending gravity minima are superimposed on this regional negative gradient. They follow the main trace of the Magallanes-Fagnano fault system, which represents the western segment of the left-lateral South America-Scotia transform plate boundary. The gravity minima reflect the presence in the subsurface of restricted and elongated basins developed within the principal displacement zone of the fault system. A relative positive gravity maximum is located just at the SE corner of the Lago Fagnano, and represents the response of a partially exposed crystalline body, occupying an area 3 x 3 km wide. A 2D vertical crustal model has been constructed, combining gravity data inversion and geological information available for the central-eastern region of Lago Fagnano. The bathymetric map of the Lago Fagnano delineates the main morphological features of this 110-km-long, 7-km-wide lake, the largest of Isla Grande. The floor is divided into distinct parts, which suggests that the basin is composed of different sub-basins. In most areas, the basin floor is highly asymmetric in shape, with flat depocentral areas. The most pronounced asymmetry of the basin is seen in the eastern end of the lake, where there is also the deepest depression. The steeper slope of the basin, along the northern shore of the Lago Fagnano, also coincides with the most pronounced regional topographic gradient. The general gravimetric and morphological features of the investigated region are here discussed.

A complete Bouguer gravity map of the central-eastern part of the Isla Grande de Tierra del Fuego, and a general bathymetric chart of the Lago Fagnano have been realized, on the basis of a series of field geophysical surveys carried out on the Island since 1998. The regional gravity anomaly trend onshore shows a progressive negative gradient from N to S. Distinct, broadly E-W-trending gravity minima are superimposed on this regional negative gradient. They follow the main trace of the Magallanes-Fagnano fault system, which represents the western segment of the left-lateral South America-Scotia transform plate boundary. The gravity minima reflect the presence in the subsurface of restricted and elongated basins developed within the principal displacement zone of the fault system. A relative positive gravity maximum is located just at the SE corner of the Lago Fagnano, and represents the response of a partially exposed crystalline body, occupying an area 3 x 3 km wide. A 2D vertical crustal model has been constructed, combining gravity data inversion and geological information available for the central-eastern region of Lago Fagnano. The bathymetric map of the Lago Fagnano delineates the main morphological features of this 110-km-long, 7-km-wide lake, the largest of Isla Grande. The floor is divided into distinct parts, which suggests that the basin is composed of different sub-basins. In most areas, the basin floor is highly asymmetric in shape, with flat depocentral areas. The most pronounced asymmetry of the basin is seen in the eastern end of the lake, where there is also the deepest depression. The steeper slope of the basin, along the northern shore of the Lago Fagnano, also coincides with the most pronounced regional topographic gradient. The general gravimetric and morphological features of the investigated region are here discussed.

English: Although beer production is one of the oldest biotechnologies in the world, a major constraint in brewing remains controlling flocculation. Evidence points towards a possible role of lipids, associated with the cell surfaces, as a major factor responsible for flocculation. Therefore, the aim in this study became to evaluate the contribution of lipids, especially oxylipins, in the flocculation of Saccharomyces cerevisiae UOFS Y-2330. Saccharomyces cerevisiae UOFS Y-2330 was selected as a model, since it was found to demonstrate both Flo1 and NewFlo phenotype flocculation behaviour, when cultivated in different media. In a defined medium with glucose as a sole carbon source, this strain immediately flocculated strongly and lost this ability before stationary phase was reached. In a complex medium containing glucose, this yeast strongly flocculated towards the stationary growth phase without losing this ability during this phase. This inverse pattern may be ascribed to a switch in sensitivity of the yeast to flocculate in the presence of glucose as well as pH level, which may, in turn, influence the availability of calcium ions. In both media, matured cells produced protuberances upon flocculation as observed by electron and immunofluorescence microscopy, which may be involved in cell adhesion. This was followed by further investigations into the role of lipids over the growth cycle of this yeast. Here, it was uncovered that Sacch. cerevisiae UOFS Y-2330 does not only demonstrate inverse flocculation, but is also characterised by two different lipid turnover patterns. During Flo1 phenotype flocculation, this yeast showed two neutral lipid accumulating stages (i.e. at 8 h and from 12 h). This is probably triggered by flocculation, which may be regarded as a survival mechanism where cells accumulate especially neutral lipids as reserve energy source - a similar mechanism is probably operative when cells enter stationary growth. Contrary to Flo1 behaviour, this s, Afrikaans: Alhoewel bierproduksie een van die oudste biotegnologiese prosesse ter wêreld is, bly die beheer oor flokkulasie ‘n groot probleem. Data dui daarop dat lipiede wat met die seloppervlaktes gedurende flokkulasie geassosieer word, moontlik ‘n groot bydraende faktor tot flokkulasie kan wees. Die doelstellings van hierdie studie is dus om die bydrae van lipiede, veral oksielipiene, tot die flokkulasie proses in Saccharomyces cerevisiae UOFS Y-2330 te evalueer. Saccharomyces cerevisiae UOFS Y-2330 is as model geselekteer, aangesien daar bevind is dat dit inverse flokkulasie patrone tydens kweking in verskillende media vertoon. In ‘n gedefinieerde medium met glukose as enigste koolstofbron, het hierdie stam dadelik sterk begin flokkuleer, maar het egter hierdie vermoë verloor voordat die stasionêre fase bereik is. In ‘n komplekse medium wat glukose bevat, het hierdie gis sterk begin flokkuleer aan begin van die stasionêre fase, sonder om hierdie vermoë gedurende hierdie fase te verloor. Hierdie inverse patroon kan moontlik toegeskryf word aan ‘n omskakeling in die sensitiwiteit van hierdie gis om by verskillende glukose-konsentrasies te flokkuleer asook pH-vlakke, wat gevolglik die beskikbaarheid van kalsium moontlik kan beïnvloed. In beide media, soos waargeneem deur elektron- en immunofluoresensiemikroskopie, het volwasse selle uitstulpings tydens flokkulasie getoon, wat moontlik betrokke kan wees in seladhesie. Dit is gevolg deur verdere ondersoeke na die rol van lipiede oor die groeisiklus van hierdie gis (op komplekse – en sintetiese media). Dit is ontdek dat Sacch. cerevisiae nie slegs inverse flokkulasie-patrone demonstreer nie, maar ook deur twee verskillende omskakelingspatrone van lipiede gekenmerk word. Gedurende Flo1- fenotipe flokkulasie, het hierdie gis twee neutrale akkumuleringstadiums in lipiede getoon (naamlik by 8 h en vanaf 12 h). Dit word waarskynlik deur flokkulasie ontlok, wat as ‘n oorlewingsmeganisme beskou word, waar selle – veral neutr, National Research Foundation (NRF)