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Slopes adjacent to the Bahamian carbonate platform revealed a large variety of depositional processes. In this study, we present a synthesis summarizing 109,000 km2 of bathymetric and reflectivity data with ∼7,900 km of seismic lines and 311 m of sediment cores that were obtained over the last 50 years. These data are used to develop a conceptual model of sedimentation patterns on Quaternary carbonate slope systems and their interaction with the adjacent shallow‐water carbonate platforms. Our data highlight that during the Quaternary, factors controlling large‐scale sedimentation on Bahamian slopes have numerous similarities as they have higher sedimentation rates during interglacials. At a small scale, every slope has its own characteristics that are contemporary controlled by two main characteristics: (a) facies on the adjacent shallow‐water platform, and (b) the impact of shallow‐ and deep‐water currents. Large‐scale tectonics influence sediment deposition as it determines the position of the islands and impacts platform facies distribution. Plain Language Summary: The factors that allow sediment to be exported from carbonate platforms to the deep‐sea need discussion. To gain a better understanding of the processes involved, the sedimentary archives of the slopes connected to these carbonate platforms are consulted. The sediments encountered vary and range from grains finer than 20 μm to coarse sandy sediments, a few millimeters in size. To understand the different processes that export those different types of sediment, we analyze various slopes of the Bahamas, a well‐known pure carbonate platform system. We used both numerical data (bathymetry, reflectivity, seismic) and sediment samples from this area and compared those records for the different Bahamian slopes. We highlighted that every slope displays a different sediment record; for every slope transect the adjacent platform facies together with deep‐sea processes (currents) determine the sediment distribution. The processes that export and transport the sediments are of equal importance. Key Points: Main factors controlling Bahamian slope sedimentation are revisedNumerous data types acquired offshore were synthesizedOur data suggest a strong influence of platform fine‐grained concentration and currents on slope sedimentation models [ABSTRACT FROM AUTHOR]

International Ocean Discovery Program (IODP) Expedition 359 cored sediments from eight borehole locations in the carbonate platform of the Maldives in the Indian Ocean. The expedition set out to unravel the timing of Neogene climate changes, in particular the evolution of the South Asian monsoon and fluctuations of the sea level. The timing of these changes are assessed by dating resultant sedimentary alterations that mark stratigraphic turning points in the Neogene Maldives platform system. The first four turning points during the early and middle Miocene are related to sea-level changes. These are reliably recorded in the stratigraphy of the carbonate sequences in which sequence boundaries provide the ages of the sea-level lowstand. Phases of aggradational platform growth give precise age brackets of long-term sea-level high stands during the early Miocene and the early to middle Miocene Climate Optimum that is dated here between 17 to 15.1 Ma. The subsequent middle Miocene cooling coincident with the eastern Antarctic ice sheet expansion resulted in a long-term lowering of sea level that is reflected by a progradational platform growth. The change in platform architecture from aggradation to progradation marks this turning point at 15.1 Ma. An abrupt change in sedimentation pattern is recognized across the entire archipelago at a sequence boundary dated as 12.9-13 Ma. At this turning point, the platform sedimentation switched to a current-controlled mode when the monsoon-wind-driven circulation started in the Indian Ocean. The similar age of the onset of drift deposition from monsoon-wind-driven circulation across the entire archipelago indicates an abrupt onset of monsoon winds in the Indian Ocean. Ten unconformities dissect the drift sequences, attesting changes in current strength or direction that are likely caused by the combined product of changes in the monsoon-wind intensity and sea level fluctuations in the last 13 Ma. A major shift in the drift packages is dated with 3.8 Ma that coincides with the end of stepwise platform drowning and a reduction of the oxygen minimum zone in the Inner Sea. The strata of the Maldives platform provides a detailed record of the extrinsic controlling factors on carbonate platform growth through time. This potential of carbonate platforms for dating the Neogene climate and current changes has been exploited in other platforms drilled by the Ocean Drilling Program. For example, Great Bahama Bank, the Queensland Plateau, and the platforms on the Marion Plateau show similar histories with sediment architectures driven by sea level in their early history (early to middle Miocene) replaced by current-driven drowning or partial drowning during their later history (Late Miocene). In all three platform systems, the influence of currents on sedimentations is reported between 11 and 13 Ma. [ABSTRACT FROM AUTHOR]

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Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Lower Pliocene temperate carbonates exhibit landward-downlapping beds at the southern margin of the Carboneras Basin in south-eastern Spain. This rarely documented stratal geometry resulted from the accumulation of bedded bioclastic carbonate sand and gravel by longshore currents along a spit platform located a few hundred metres from the palaeoshoreline. The top of the spit platform was covered by shoals that extended over a gently dipping ramp inclined to the north. On the landward slope of the spit, sediments washed over from the shoal area were deposited in parallel-laminated beds with a southward dip of 8–11°. These beds aggraded and retrograded after an increase in accommodation space, probably related to an Early Pliocene eustatic sea-level rise. As a result, the beds downlap onto the underlying unconformity surface in a shoreward direction. Eventually, the depression between the shoreline and the spit platform was filled, and a gentle ramp became established. These Pliocene exposures in the Carboneras Basin and a similar Upper Miocene example in southern Spain suggest that landward-downlapping stratal geometries can be expected in nearshore temperate carbonates along basin margins, and demonstrate a similarity in sedimentary dynamics to siliciclastic sands and gravels. [ABSTRACT FROM AUTHOR]

Objective Mutations of the SCN9A gene can cause ion channel dependant pain syndromes, generalized epilepsy with febrile seizures or familial febrile seizures, following an autosomal dominant or recessive inheritance. Furthermore cardiac symptoms such as bradycardia with syncopes up to asystole and tachycardia have been described. We present a case of a familial generalized epilepsy with additional paroxysmal tachycardia that has successfully been treated with carbamazepine. Case description Our 5-year-old patient first had absence-like seizures at the age of 3 years, with a frequency of approximately twice a month and a duration of 5 to 10 seconds. The EEG showed paroxysmal generalized polyspike wave complexes. Since the age of 4 years the patient had also suffered from episodes with paroxysmal tachycardia. The patient's mother and her sister had similar seizures in early childhood, both were successfully treated with carbamazepine (CBZ). The mother also suffers from episodes with paroxysmal tachycardia which are accompanied by panic attacks. In our patient, the heterozygous modification c.684C>G; p.I228M was detected in the SCN9A gene, using “next generation sequencing”. The mutation could also be detected in the patient's mother. A therapy with CBZ reduced both the boy's seizure frequency and the frequency of his paroxysmal tachycardia significantly. Discussion SCN9A mutations have also been described for Dravet syndrome and familial febrile seizures, whereas our patient showed a familial absence-like generalized epilepsy in combination with paroxysmal tachycardia. Our patient, his mother and also his aunt were successfully treated with CBZ, which could suggest that the patient's c.684C>G; p.I228M mutation causes a “gain of function” of the Nav1.7 sodium channel. The additional cardiac symptoms could also be an effect of the SCN9A mutation. [ABSTRACT FROM AUTHOR]

New hydroacoustic data, high resolution multichannel seismic reflection data, CTD casts and sampling document the dominance of bottom currents and the occurrence of carbonate mounds in the Santaren Channel off Great Bahama Bank and Cay Sal Bank. Based on these data sets, three types of carbonate mounds have been identified in water depths between 285 and 685 m. Their distribution is strongly related to the present current regime. Bank-driven sediments are caught up by the currents and redeposited mainly in the channel center, resulting in the accumulation of giant confined drifts flanked by moats. The moats at the banks toe-of-slope are formed by a southward and northward flowing water mass, respectively, mainly Antarctic Intermediate Water and Subtropical Underwater. The observed carbonate mounds are concentrated in these moats. Mound type 1 has an elongated shape parallel to the prevailing bottom current direction, a gently inclined flank facing the water flow and a steep flank in its current shadow. Its upstream flank is covered by a thin sediment wedge whereas the lee side is marked by a parabolic scour. Type 1 occurs at both bank margins but mainly off Great Bahama Bank, consisting of cold-water coral rubble floating in a sediment matrix and is, thus, interpreted as cold-water coral mound. By contrast, type 2 mounds are restricted to the Cay Sal margin and have a predominately conical outline. Bottom samples including living sessile crinoids show that its surface must be lithified and colonized by macroepibenthos, except corals. The mounds are situated in pockmark-like depressions that are underlain by fluid escape structures like pipes and chimneys. These fluid pathways are generated by a network of fractures. Mound type 2 is probably formed by abiotic carbonate precipitation; however, a chemoherm nature cannot be ruled out. Mound type 3 has a conical to polygonal shape and occurs off Cay Sal Bank and Great Bahama Bank. It is surrounded by a scour which is elongated in downcurrent and crescent in upcurrent direction. A sediment bulge formed at its front. This type is consistent with blocks and boulders colonized by macroepibenthos and related to gravity-controlled mass movements at the steep bank slopes. Principally, two habitats can be distinguished: the Great Bahama Bank periplatform deep-water province dominated by mound type 1 and the Cay Sal Bank slope to basin province occupied by mound type 2 that is associated with pockmark-like structures. Mound type 3 occurs in both habitats. Physical water mass properties for the existence of cold-water corals are limited to a depth range of ca. 430 to 685 m, with seawater densities ( σ - θ ) of 26.93 to 27.29 kg/m and temperatures below 13 °C. Their dominance off Great Bahama Bank might be addressed to a more effective food supply induced by local downwelling. [ABSTRACT FROM AUTHOR]