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1.
Chemosphere ; 303(Pt 3): 135194, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35660056

ABSTRACT

The long-term monitoring of the cosmogenic 7Be activity concentrations has been used to better understand the influence of large-scale atmospheric circulation dynamics in the troposphere. With an aim, this study analyzes weekly 7Be data from 15 sampling stations in Europe over 2005-2014. We first define peak (or extremely high) events in each station as those activity concentrations above the 90th percentile, and then investigate their temporal and spatial variability. These events are most frequent in the spring and summer seasons, with a notable latitudinal variability in their number. Next, we use back-trajectory cluster analysis to identify the main advection pathways associated with these high concentrations. To achieve this, persistent periods, i.e., sampling periods over which at least 60% of the calculated backward trajectories arriving at a given site correspond to the same airflow pattern, are taken as reference. This method reveals large differences in the association between the airflow patterns observed at different stations in connection with the 7Be peaks. A comparison between stations shows no clear spatial pattern, which suggests a further influence of mesoscale/local physical processes on the surface 7Be activity concentrations. Finally, the main airflow pattern at each sampling site and the associated 7Be peaks, are related to the main teleconnection patterns of large scale and regional climate variability in Europe: North Atlantic Oscillation, Arctic Oscillation, East Atlantic, East Atlantic/Western Russia, Scandinavian pattern and Western Mediterranean Oscillation. The results point out the connection between the negative phases of NAO and We-MO, and the positive phase of EA with the spatial and temporal variability and occurrence of the 7Be peak activity concentrations. These results show a latitudinal division between northern and southern sites, with similar influence of teleconnection patterns, while those located in the central part of Europe present larger variability in the impact of teleconnection patterns.


Subject(s)
Atmosphere , Environmental Monitoring , Climate , Environmental Monitoring/methods , Europe , Seasons
2.
Chemosphere ; 199: 278-285, 2018 May.
Article in English | MEDLINE | ID: mdl-29448195

ABSTRACT

Relationships between the beryllium-7 activity concentrations in surface air and meteorological parameters (temperature, atmospheric pressure, and precipitation), teleconnection indices (Arctic Oscillation, North Atlantic Oscillation, and Scandinavian pattern) and number of sunspots are investigated using two multivariate statistical techniques: hierarchical cluster and factor analysis. The beryllium-7 surface measurements over 1995-2011, at four sampling sites located in the Scandinavian Peninsula, are obtained from the Radioactivity Environmental Monitoring Database. In all sites, the statistical analyses show that the beryllium-7 concentrations are strongly linked to temperature. Although the beryllium-7 surface concentration exhibits the well-characterised spring/summer maximum, our study shows that extremely high beryllium-7 concentrations, defined as the values exceeding the 90th percentile in the data records for each site, also occur over the October-March period. Two types of autumn/winter extremes are distinguished: type-1 when the number of extremes in a given month is less than three, and type-2 when at least three extremes occur in a month. Factor analysis performed for these autumn/winter events shows a weaker effect of temperature and a stronger impact of the transport and production signal on the beryllium-7 concentrations. Further, the majority of the type-2 extremes are associated with a very high monthly Scandinavian teleconnection index. The type-2 extremes that occurred in January, February and March are also linked to sudden stratospheric warmings of the Arctic vortex. Our results indicate that the Scandinavian teleconnection index might be a good indicator of the meteorological conditions facilitating extremely high beryllium-7 surface concentrations over Scandinavia during autumn and winter.


Subject(s)
Air Pollutants, Radioactive/analysis , Beryllium/analysis , Radiation Monitoring/methods , Radioisotopes/analysis , Atmosphere/chemistry , Atmospheric Pressure , Climate Change , Factor Analysis, Statistical , Scandinavian and Nordic Countries , Seasons , Temperature
3.
Acta Chir Iugosl ; 41(2): 119-23, 1994.
Article in Croatian | MEDLINE | ID: mdl-7785387

ABSTRACT

The routinely monitored variables in shock stages include: arterial pressure, heart rate, central venous pressure, pulmonary artery wedge pressure and cardiac index. With vigorous therapy it is possible to bring these values back into the normal range in both survivors and nonsurvivors. The therapeutic goal in septic shock stages is to maximize the values of cardiac index, O2 delivery (DO2) and O2 consumption (CO2). The aim of this study is to determine the relationship between O2 delivery and O2 consumption as an early sign of hypoxia. Fifteen patients with septic shock were treated in order to maximize the value of CI, DO2 and VO2. We compared the levels of these parameters between the survivors and nonsurvivors and found no significant differences after 24 hours. High levels of DO2 and VO2 do not exclude tissue hypoxia in the early stage of septic shock.


Subject(s)
Hypoxia/blood , Oximetry , Shock, Septic/complications , Adult , Aged , Female , Humans , Hypoxia/complications , Male , Middle Aged
4.
Acta Chir Iugosl ; 36 Suppl 2: 434-6, 1989.
Article in Croatian | MEDLINE | ID: mdl-2618395

ABSTRACT

The authors present a series of 36 patients operated on for severe intraabdominal bleeding due to spleen trauma. Patients were treated from 02. December 1987 till 30. June 1988 in Emergency Center-Surgical Clinic-University Clinical Center Belgrade (Institute of digestive pathology). The standard operative procedure has been removal because splenic salvage is unreasonable if there is ungoing bleeding and multiple associated injuries. Splenectomy was performed in 32 (88 percent). Overall mortality rate was 9%. Authors want to stress out the role of team in successful treatment of polytraumatized patients.


Subject(s)
Hemorrhage/diagnosis , Spleen/injuries , Abdominal Injuries/diagnosis , Humans , Multiple Trauma
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