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Number of results: 39
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Abstract

Phytoplankton samples were collected at 141 stations in the Norwegian, Greenland, Barents and Baltic seas, in July-August 1992 and July-August 1993. In fifteen of these stations 22 unarmoured dinoflagellate species from the order Gymnodiniales belonging to the genera Amphidinium, Cochlodinium, Gymnodinium, Gyrodinium, Torodinium and Polykrikos have been found. Data on 16 species are given here, including synonyms, size or size variation, localities and environmental factors (temperature and salinity at the surface). 14 species are illustrated.
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Abstract

The article presents the most frequent surname in Lithuania — Kazlauskas. Referring to the article “Mysterious Lewandowski” by K. Skowronek (2000), an attempt has been made to account for this frequency in three various ways. First, the principles behind the quantitative structure of anthroponomasticons (Zipf’s law) and the loss of surnames (genetic drift) are discussed. Then the Slavic origin of the surname under consideration has been highlighted as a typical trait of the majority of surnames in Lithuania. In connection with this fact, it has been stressed that caution must be exercised in proposing a thesis on its origin as a translation from Lithuanian on a mass scale, since this thesis requires plentiful empirical evidence. Finally, the etymology of the name is analyzed. Morphologically it is a typical surname derived from a toponym. This supposition is additionally supported by the existence in Poland of numerous localities called Kozłów, Kozłowo or similar name; these in turn are most likely to have been derived from appellative-based personal names of their owners or inhabitants, such as Kozieł.
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Abstract

Phytoplankton samples were collected at 62 stations in the European Arctic Seas and the Faroe — Shetland Islands area. Over 30 species of dinoflagellates were found. 22 species are illustrated by original drawings. The data on synonyms, size or size variability on the distribution and environmental factors (temperature and salinity) are given.
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Abstract

Eight samples of the ice algae were collected from the annual ice in Tikhaia Bay, Hooker Island, Franz Josef Land. Species composition included 58 diatoms (and some Navicula, Nitzschia and other Pennatophyceae unidentified species), 2 dinoflagellates, 2 chrysophyceans, 1 chlorophycean, 1 cyanophycean and possible dinoflagellate and chrysophycean cysts. The maximum quantity was 132300 cells/l. In 4 samples Aulacoseira granulatu prevailed, in other samples Nitzschia frigida, N. cylindrus, Rhizoclonium sp. and dinoflagellate cysts dominated. Xanthiopyxis polaris found by Gran (1904) in Arctic sea ice and referred to the diatoms is, possibly, the dinoflagellate cyst. On the whole, the ice community consisted of benthic and planktonic-benthic species of mainly marine and brackishwater-marine pennate diatoms, their resting stages, freshwater unicellular algae and marine chlorophycean.
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Abstract

Phytoplankton samples were collected at 74 stations in the European Arctic seas, 28 species of the armoured din oft age Hates being found. Thirteen dinoflagellates are illustrated by original drawings. The data on synonyms, size or size variation, localities and environmental factors (temperature and salinity) at the surface are given.
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Abstract

“The influenza virus behaves just as it seems to have done for five hundred or a thousand years, and we are no more capable of stopping epidemics or pandemics than our ancestors were,” wrote Charles Cockburn from the World Health Organization back in 1973. Is his remark still just as apt today?
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Abstract

In the region of Bransfield Strait and southern part of Drake Passage the highest amounts of chlorinated hydrocarbons (CHs — compounds of the DDT group, HCH isomers and PCBs) were found in the samples taken at the sampling station where the CHs bottom deposits were released to the upper layers due to the special hydrological situation at this station. Increased amounts of CHs were observed also in phytoplankton sampled close to the melting ice of glacier origin which was considered as a source of pollution. However, phytoplankton sampled from the waters covered with pack-ice exhibited the lowest rate of CHs accumulation. Slightly elevated CHs accumulation was found in sea ice diatoms. All the samples exhibited elevated amount of polichlorinated biphenyls, markedly higher than that of chloroorganic insecticides.
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Abstract

In Antarctic summer 1983/1984 samples of planktonie and attached diatoms were collected in the Admiralty Bay (King George Island, South Shetland Islands) as well as samples of planktonie diatoms in the region of South Orkneys, Drake Passage and Bransfield Strait (BIOMASS-SIBEX Project). Using gas chromatography residues of chloroorganic pesticides, namely the compounds of the DDT group and HCH isomers were determined. It was found that the highest values of the content of these compounds occurred in attached diatoms coming from areas continuously washed with water from the melting glacier, in planktonie diatoms from the samples of the Admiralty Bay and from strongly glaciated regions. A hypothesis was put forward that along with the direct atmospheric transport the release of the deposits of these compounds from ice and glaciers during their melting is an additional source of input of chloroorganic biocides into Antarctic waters. Diatoms are good indicators of this process.
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Abstract

Moulting southern elephant seals, Mirounga leonina (L.), were counted in 17 discrete wallows at Walker Bay on Livingston Island in the South Shetland Islands between 2 January and 16 February 1994. Daily weather conditions were also recorded. It was also found that, although there were no overall correlations between wind scale, air temperature, sunshine, precipitation, sea roughness and cloud cover with seal numbers, there were conditions on specific days that affected the movements of seals between wallows. Most notably, it was found that numbers of seals decreased when they were exposed to winds, and that they often sought out more sheltered sites nearby.
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Abstract

232 specimens of Notothenia coriiceps neglecta and 578 specimens of Notothenia rossi marmorata were collected in the region of Admiralty Bay during the period from March to December 1977. The age of the fish was determined from scales. Length — weight relationship was calculated for both species. The parameters of the von Bertalanffy equation were calculated for Notothenia coriiceps neglecta, whereas mean lengths for Notothenia rossi marmorata were given according to the particular age groups.
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Abstract

Species diversity of Collembola was studied in the vicinity of Polish Polar Station, Hornsund area, West Spitsbergen. A list of 32 species has been compiled, and their distribution over microlandscapes and microhabitats in the study area has been presented.
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Abstract

The aim of the study was to compare anaesthesia protocol utilizing combination ketamine/ medetomidine with epidural lidocaine or morphine to orthopaedic surgery in rabbits. All rabbits received intramuscularly medetomidine (0.5 mg/kg) and ketamine (20 mg/kg). In group L (n=13) epidural injection was performed with lidocaine (3 mg/kg) and in group M (n=13) with morphine (0.1 mg/kg) diluted with sterile saline to 0.6 ml. Rabbits underwent bilateral mosaicplasty surgery. Heart rate (HR), systolic (SBP), diastolic (DBP) and mean arterial blood pressure (MAP), arte- rial oxygen saturation (SpO2) and respiratory rate (RR) were measured every 5 minute during surgical procedure. Duration of sensory blockade was measured based on toe pinch reflex and recorded. Hemodynamic parameters were comparable at baseline in both groups. We did not observe significant differences in HR, RR, SBP, DBP, MAP between group L and M. Intragroup statistical analysis revealed differences at different time points in group M in terms of HR, SBP, DBP, MAP. In rabbits in group M blood pressure dropped while HR increased over time. In both groups a decrease in SpO2 was observed. Mean duration of loss of the toe pinch reflex was similar between group L and M, and amounted to 72.79±34.48 and 82.80±17.85 minutes, respectively.
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Abstract

Communities of soil invertebrates were studied in 4 types of tundra ecosystems on Spitsbergen (Hornsund area) during the vegetative season of 1989. Taxonomic composition, density and biomass of soil fauna were evaluated in the sites along a gradient of increase in the biogenic impact of bird colonies, i.e. in polygonal tundra, mossy/lichenous tundra, Calliergon stramineum moss association, and mossy associations near a colony of Little Auks (Alle die). Average total biomass of soil invertebrates increased in this site sequence from 1.1 to 25.0 g wet weight x m-2 (mainly due to collembolans and nematodes). Seasonal dynamics of all groups of soil meso- and macrofauna (Nematoda, Enchytraeidae, Aranei, Acarina, Collembola, Coleoptera, Diptera larvae) is presented and discussed.
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Abstract

Contents of PCBs was investigated using the gas chromatography method in the tissue of four Antarctic migratory birds: Oceanites oceanicus, Larus dominicanus, Catharacta skua and Sterna vittata, and the three penguin species: Pvgoscelis adeliae, P. papua and P. antarctica. Samples were collected at King George Island in February 1978 and, for comparison, in March 1983. The highest PCBs content was recorded in the adipose tissue of O. oceanicus and C. skua (15.7 and 1.2 ppm). Differences in the content of these compounds in the tissue of various penguin species in 1978 was observed. The mean cumulation level of PCBs in the adipose tissue of penguins was higher in 1983 than in 1978. Differences in the level of PCBs contents in the tissue of migratory birds were related to their winter migrations to areas polluted to various degress with PCBs remains. A tendency to the increase of the contamination of penguin tissues with PCBs was observed. This tendency was related to the increase of vhe pollution of the Antarctic environment with these compounds.
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Abstract

In 1979- 1981 at the King George Island samples of adipose tissue of 5 pinniped species (L. carcinophagus, L. weddelli, H. leptonyx, M. leonina and A. gazella) were collected and the contents of chlorinated hydrocarbons (CHs) were determined with the gas chromatography method. The highest values were recorded in the leopard seal (432.3 -614.7 ppb DDT), the second highest values in the mature elephant seal (73.4 ppb DDT) and the third in the Weddell seal (54.4 — 69.1 ppb DDT). In the Weddell seal the highest level of HCH content (23.3 — 32.1 ppb) was recorded. A decrease in the content of pp'DDE in the adipose tissue of crabeater seal in successive years was recorded, the values being 36.8 ppb in 1979, 24.4 ppb in 1980 and 15.3 ppb in 1981, as well as an increase in the concentration of HCH (15.3 ppb in 1980 and 27.4 ppb in 1981). The contents of CHs in the adipose tissue of Antarctic pinnipeds are 100—1000 times lower than those in the Arctic seals.
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Abstract

Introduction: Arthrocentesis has been used in the temporomandibular joint (TMJ) to analyze components of the synovial fluid or as a therapeutic procedure associated or not with the admini- stration of a drug. The rabbit is one of the most commonly used animal species as a model for pathologies that affect the TMJ. The aim of this study was to propose a specific technique to perform arthrocentesis on the rabbit TMJ, emphasizing descriptions of reference points and measurements for a successful puncture without complications. Materials and methods: Fourteen adult rabbits (Oryctolagus cuniculus) were used. The project was approved by the Scientific Ethics Committee of the Universidad de La Frontera (File Nº083/2016). Results: The description of the technique was divided into three steps: 1) Location of the rabbit TMJ, 2) Positioning of the needles in the TMJ, and 3) Passage of fluid through the TMJ. Conclusions: This arthrocen- tesis technique could help to simplify the procedure and give the investigator a guide for joint washing and extraction of synovial fluid in the rabbit TMJ.
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Abstract

Rockburst is a common engineering geological hazard. In order to evaluate rockburst liability in kimberlite at an underground diamond mine, a method combining generalized regression neural networks (GRNN) and fruit fly optimization algorithm (FOA) is employed. Based on two fundamental premises of rockburst occurrence, depth, σθ, σc, σt, B1, B2, SCF, Wet are determined as indicators of rockburst, which are also input vectors of GRNN model. 132 groups of data obtained from rockburst cases from all over the world are chosen as training samples to train the GRNN model; FOA is used to seek the optimal parameter σ that generates the most accurate GRNN model. The trained GRNN model is adopted to evaluate burst liability in kimberlite pipes. The same eight rockburst indicators are acquired from lab tests, mine site and FEM model as test sample features. Evaluation results made by GRNN can be confirmed by a rockburst case at this mine. GRNN do not require any prior knowledge about the nature of the relationship between the input and output variables and avoid analyzing the mechanism of rockburst, which has a bright prospect for engineering rockburst potential evaluation.
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Abstract

In this work, the influence of microwave drying parameters such as irradiation time and microwave power level on the properties of synthetic moulding sands is presented. Determination of compressive strength Rc s, shear strength Rt s and permeability Ps of synthetic moulding sands with the addition of two different bentonites, after drying process with variable microwave parameters were made. The research works were carried out using the microwave oven with regulated power range of the electromagnetic field. From the results obtained, the significant influence of both drying time and microwave power level on the selected properties of moulding sands was observed. In comparison to the conventional drying method, microwave drying allows to obtain higher compressive strength of the synthetic moulding sand. The influence of application microwave irradiation on permeability was not observed. Higher strength characteristics and shorter drying time are major advantages of application of the electromagnetic irradiation for drying of the synthetic moulding sand with regard to conventional drying method.
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Abstract

It has been shown in the present paper that exploitation of the experimental potential of a photoacoustic technique can provide information on a type of intermolecular interactions in aqueous mixtures containing organic liquids, when the basic parameters of these mixtures, such as density, ρ, specific heat, cp, or thermal conductivity, λ, are unknown. Earlier investigations of concentration dependence of effusivity in different aqueous solutions of organic liquids demonstrated that the photoacoustics method is a sensitive tool to identify hydrophobic properties of such liquids. In our experiment this suggestion was exploited for a solution of methanol which is known to display much weaker hydrophobicity than other alcohols. It was confirmed that the location of extreme deviations from linearity for the thermal effusivity, Δe, agrees well with that of characteristic points for the isentropic compressibility coefficient, κS, and the excess molar volume, V_m^E, as a function of the concentration.
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Abstract

The aim of our study was to determine the influence of L-carnitine (L-CAR) on the cellular parameters of hen erythrocytes during a 48 hour exposure to L-CAR at concentrations of 25, 50 and 100 mg/mL in nutrient-deficient medium. Cell morphology, haemolysis, caspase 3/7 activity and glucose uptake (GU) were determined. The results showed a lower percentage of apoptotic cells and decreased haemolysis of erythrocytes treated for 48 hours at all the concentrations of L-CAR. The amino acid at 50 mg/mL inhibited the activity of proapoptotic caspase 3/7; however, it increased GU. In contrast, caspase 3/7 level was increased but GU was decreased in erythrocytes treated with 100 mg/mL of L-CAR when compared to the control. It may be hypothesized that reduction of apoptotic changes in hen erythrocytes may result from increased GU.
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Abstract

Disseminated intravascular coagulation (DIC) is a complex, dynamic and hemostatic disorder which develops secondarily to a disease characterized with an imbalance in the pro-coagulant and anti-coagulant components of hemostasis. The aim of the study is to evaluate hemostatic dysfunc- tion and the DIC syndrome in cattle with displaced abomasum (DA), with using the hematologic analyses and an extensive coagulation profile in the 96 hour-period including before and after surgery. The animal material of the study consisted of 12 dairy cows diagnosed with displaced abomasum (9 LDA and 3 RDA without volvulus) in the 2-4 week period after parturation and with no other post-partum disease. In dairy cows diagnosed with DA, hematological, coagulomet- ric (PT, APTT, Fibrinogen) and coagulation factor analyses [D-Dimer, TAT (thrombin-anti- thrombin complex), ATIII (antithrombin III), PAI-1 (plazminogen activator inhibitor-1] were performed in blood samples obtained before the operation as well as 30 minutes, 60 minutes and 2, 5, 10, 24, 48, 72 and 96 hours after the operation. In the DA cases, abnormalities were found in 6 of the 8 coagulation parameters. In the LDA and RDA groups, prolonged PT (sec), PT (INR) and APTT, hypofibrinogenemia, an increase in serum D-Dimer concentration at 72 and 96 hours after the operation and an increase in serum ATIII concentrations before and 30, 60 minutes and 2, 5, 72 and 96 hours after the operation was found (p<0.05). Hemostatic dysfunction and the risk of DIC developing in DA cases and continuing in the post-operative period was determined.
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Abstract

Suspended matter, phytoplankton and light attenuation were investigated in various North East Greenland, Svalbard and Siberian river mouths in 1992-1994. The amount of mineral suspensions well correlated with freshwater discharge in the case of tidal glacier bays, while such correlation in Siberian rivers and pack ice meltwater was not found. Freshwater phytoplankton species were found in Siberian estuaries only and in two other ecosystems marine and ice phytoplankton species prevailed. The light attenuation connected with freshwater discharge seems to be a key factor limiting primary production in coastal Actic waters in the summer. The amount of glacial suspensions well correlated with the salinity drop in the case of Svalbard, while Siberian river estuaries produced very turbid waters with the suspension loads not correlated to freshwater or depth.
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Abstract

The number of human cases of salmonellosis in the EU was 94,625 in 2015. Considering the source of these infections, Salmonella spp. was most frequently detected in broiler chicken meat and Salmonella Enteritidis (SE) was the most commonly reported serovar. The efficacy of probiotics in limiting Salmonella spp. infection in poultry has been demonstrated in numerous papers. The administration of probiotics at the level of primary production reduces the risk of contamination of poultry food products with Salmonella spp. A study was carried out in order to determine the potential for reducing the Salmonella spp. population in broiler chickens with the use of the Lavipan (JHJ, Poland) probiotic that comprised selected stains of lactic acid bacteria and Saccharomyces cervisae. Salmonella spp.-free broiler chickens were divided into two groups and received the same feed with (group L) or without (group C) the probiotic throughout the experiment. All day-old chickens were infected per os with SE. Samples of cecum content were collected 2, 4, and 6 weeks after SE infection and pectoral muscles were collected 6 weeks following SE infection for the evaluation of the SE population number. Serum samples for serological examinations were collected 6 weeks after infection. Six weeks after infection, the number of SE-positive cecal samples was lower in the L group (12.5% positive) in comparison to the C group (87.5%). Similar results were demonstrated for the muscle samples (25% in contrast to 87.5%). At the same time, in both cases, the SE CFU/g was significantly lower in the L group. The results of our study indicate that Lavipan was capable of reducing the population of SE in the gastrointestinal tract, which eventually improved the hygienic parameters of the pectoral muscles. Four weeks after infection, SE was not detected in any of the experimental groups. In both groups, no specific anti-SE antibodies were detected.
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