30 research outputs found
Spatial and Temporal Changes of Tidal Inlet Using Object-Based Image Analysis of Multibeam Echosounder Measurements: A Case from the Lagoon of Venice, Italy
Scientific exploration of seabed substrata has significantly progressed in the last few years.
Hydroacoustic methods of seafloor investigation, including multibeam echosounder measurements,
allow us to map large areas of the seabed with unprecedented precision. Through time-series of
hydroacoustic measurements, it was possible to determine areas with distinct characteristics in the
inlets of the Lagoon of Venice, Italy. Their temporal variability was investigated. Monitoring the
changes was particularly relevant, considering the presence at the channel inlets of mobile barriers
of the Experimental Electromechanical Module (MoSE) project installed to protect the historical
city of Venice from flooding. The detection of temporal and spatial changes was performed by
comparing seafloor maps created using object-based image analysis and supervised classifiers.
The analysis included extraction of 25 multibeam echosounder bathymetry and backscatter features.
Their importance was estimated using an objective approach with two feature selection methods.
Moreover, the study investigated how the accuracy of classification could be affected by the scale of
object-based segmentation. The application of the classification method at the proper scale allowed
us to observe habitat changes in the tidal inlet of the Venice Lagoon, showing that the sediment
substrates located in the Chioggia inlet were subjected to very dynamic changes. In general, during
the study period, the area was enriched in mixed and muddy sediments and was depleted in sandy
deposits. This study presents a unique methodological approach to predictive seabed sediment
composition mapping and change detection in a very shallow marine environment. A consistent,
repeatable, logical site-specific workflow was designed, whose main assumptions could be applied to
other seabed mapping case studies in both shallow and deep marine environments, all over the world
Przypadek 12-letniego chłopca z ostrą białaczką limfoblastyczną po zgodnym w układzie ABO allo-HSCT, u którego wykryto obecność przeciwciał klasy IgG o swoistości anty-A
This review suggested that if there is compatibility ABO between recipient and donor, immunohematologicial research before allo-HSCT (when blood is A and AB group) should also include the research of the serum donor with A1 group red blood.Wyniki uzyskane w niniejszej pracy wskazują na potrzebę wykonania badań immunohematologicznych surowicy dawcy/biorcy nie tylko z krwinkami wzorcowymi grupy krwi O, ale także z krwinkami grupy krwi A1, w przypadku istnienia zgodności w układzie ABO pomiędzy biorcą i dawcą komórek krwiotwórczych o grupie krwi A i AB
Morpholithodynamical changes of the beach and the nearshore zone under the impact of submerged breakwaters — a case study (Orłowo Cliff, the Southern Baltic)
SummarySubmerged breakwaters (SBWs) were used for the first time on the Polish coast in 2006, in the western coast of Gdańsk Bay, in the area of Orłowo Cliff. They were built to prevent the abrasion and inundation of areas situated in the hinterland, especially in the conditions of storm surges. The main objective of the study was to determine their effect on the morphology and grain size composition in the seashore and nearshore zone.Based on the conducted research and analysis, it has been found that the construction has a minor impact on the modification of the shore and nearshore zone morpholithodynamics, which is evidenced by a sinuate shape of the shoreline and a relatively stable cape in the central part of the area, present both before (1966–2005) and after SBWs were built. Furthermore, the progressive abrasion, the lack of significant changes in the morphology and particle size distribution of the beach and the nearshore zone, as well as the fact that those changes are limited only to the immediate surroundings of the submerged breakwaters prove their neutral impact
Effect of diet on the capacity to remove mercury from the body of a penguin (Spheniscus demersus) living in the ZOO
Birds due to its position in the trophic chain are good monitors of the marine environment in terms of mercury contamination. For the proper interpretation of results it is necessary to know both the processes of accumulation of this metal in their bodies and processes of elimination. Research involving the Penguin (Spheniscus demersus) living in a ZOO has identified the relationship between diet and the amount of mercury removed from the penguin body in guano, feathers, and in the case of females with eggs. The research was conducted in years 2009-2011. Total mercury was determined in elements responsible for detoxification and in the diet of penguins. Mercury concentration was determined by atomic absorption spectrophotometry with AMA-254 automatic mercury analyzer. The highest average mercury concentrations were determined in feathers: 1781.12 ngHg•g−1d.w., lower in eggs: 950.88 ngHg•g−1 dry weight (d.w.). and in a guano: 139.18 ngHg•g−1. In food, herrings caught in the southern Baltic, Hg concentrations were relatively low with averaged value 31.81 ngHg•g−1d.w