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Number of results: 6
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Abstract

Based on the results of CTD measurements (in situ) made during r/v „Oceania" cruises in the Norwegian and Greenland Seas in 1986—1988 selected aspects of termohaline structure and water dynamics of chosen regions of the seas were described. Examples of space-time variations of temperature and salinity fields were presented and water masses geostrophic transport on the limits of the Norwegian Sea (upon the Atlantic Ocean and the Barents Sea) was estimated.
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Abstract

In the years 1987-1989, within the frames of the international program "Greenland Sea Project", the Institute of Oceanology of Polish Academy of Sciences carried out the oceanographic investigations in the energoactive zones of the Northern Atlantic. The paper presents some results of these investigations, characterizing interannual variability of aero- and hydrophysical fields and the causal connections between hydrological and hydrobiological anomalies. Main results of these investigations indicate that the summer season of 1988 was an anomaly in the region of confluence of Barents and Norwegian Seas. This result is irrefutably confirmed by biological data concerning species, and hydrophysical data, such as light attenuation coefficient, fluorescence, spatial distributions of water temperature, salinity, density and current velocity, as well as mass and heat fluxes. It arises from these information that the southern border of the confluence zone was normally the heat „source", while in 1988 it was the heat „sink". The results obtained indicate two reasons responsible for such a situation. The first is the anticyclonic eddy structure of cold Barents Sea waters, penetrating the confluence zone. The second reason seems to be a mechanism blocking the transport of Atlantic water masses through the transect between Faeroe and Shetland Islands.
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Abstract

Two West Spitsbergen fiords, Hornsund (77°N) and Kongsfjorden (79°N) were compared with respect to their hydrology and zooplankton occurrence on the base of two summer surveys made in 1987 and 1988. Both fiords were found to be influenced by four types of masses: Atlantic Waters, Intermediate Atlantic Waters, Local Waters and Brackish Surface Waters, Intermediate Atlantic Waters, Local Waters and Brackish Surface Waters. The amount of fresh water in both fiords reached up to 10% of water volume of the uppermost water layers. Hornsund in August 1987 was richer in mesozooplankton biomass than Kongsfjorden in 1988. Estimated energie value of pelagic prey of marine birds was 180-500 KJ/100 m3 in Hornsund, and 130-200 in Kongsfjorden. Two major plankton communities were found in both fiords: Pseudocalanus community in the inner fiord basins and Calanus dominated community in the outer areas of the fiords. Plankton occurrence in fiords was not linked directly with the temperature — salinity patterns but rather with dynamic phenomena like upwellings and wind drift of surface waters.
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Abstract

We describe surface currents in the Porsanger fjord (Porsangerfjorden) located in the European Arctic in the vicinity of the Barents Sea. Our analysis is based on surface current data collected in the summer of 2014 using High Frequency (WERA, Helzel Messtechnik GmbH) radar system. One of our objectives was to separate out the tidal from the nontidal components of the currents and to determine the most important tidal constituents. Tides in the Porsanger fjord are substantial, with tidal range on the order of about 3 m. Tidal analysis attributes to tides about 99% of variance in sea level time series recorded in Honningsvaag. The most important tidal component in sea level data is the M2 component, with amplitude of ∼90 cm. The S2 and N2 constituents (amplitude of ∼20 cm) also play a significant role in the semidiurnal sea level oscillations. The most important diurnal component is K1 with amplitude of about 8 cm. The most important tidal component in analyzed surface currents records is the M2 component. The second most important component is the S2. Our results indicate that in contrast to sea level, only about 10-30% of variance in surface currents can be attributed to tidal currents. This means that about 70-90% of variance is due to wind-induced and geostrophic currents.
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Abstract

Background and Aim: Patients with acute pulmonary embolism (APE) associated with hemodynamic instability, i.e. high-risk APE (HR-APE), are at risk for early mortality and require urgent reperfusion therapy with thrombolysis or embolectomy. However, a considerable proportion of HR-APE subjects is not reperfused but only anticoagulated due to high bleeding risk. The aim of the present study was to assess the management of HR-APE in a single large-volume referral center. Methods: A single-center retrospective study of 32 HR-APE subjects identified among 823 consecutive patients hospitalized for symptomatic APE. Results: Out of 32 subjects with HR-APE (19 women, age 69 ± 19 years), 20 patients were unstable at admission and 12 subsequently deteriorated despite on-going anticoagulation. Thrombolysis was applied in 20 (62.5%) of HR-APE subjects, limited mainly by classical contraindications in the remainder. Percutaneous pulmonary embolectomy was performed in 4 patients. In-hospital PE-related mortality tended to be higher, albeit insignifi cantly, in the patients who developed hemodynamic collapse during the hospital course compared to those unstable at admission (67% vs. 40%, p = 0.14). Also, survival was slightly better in 22 patients treated with thrombolysis or percutaneous embolectomy in comparison to 10 subjects who received only anticoagulation (54% vs. 40%, p = 0.2). Major non-fatal bleedings occurred in 7 of 20 patients receiving thrombolysis (35%) and in 2 (17%) of the remaining non-thrombolysed 12 HR-APE subjects. Conclusions: Hemodynamically instability, corresponding to the definition of HR-APE, affects about 4% of patients with APE, developing during the hospital course in approximately one-third of HR-APE subjects. As almost 40% of patients with HR-APE do not receive thrombolytic therapy for fear of bleeding, urgent percutaneous catheter-assisted embolectomy may increase the percentage of patients with HR-APE undergoing reperfusion therapy. Further studies are warranted for a proper identification of initially stable intermediate-risk APE subjects at risk of hemodynamic collapse despite appropriate anticoagulation.
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