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Number of results: 1095
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Abstract

Heat shock proteins 70 (Hsp70) are potential thermal stress markers as they play a pivotal role in safeguarding cells against heat shock-induced damage. The Hsp70s are present in several variants with each containing its peculiar importance due to their specific functions such as cell protection during elevated thermal stress. The present investigation evaluated the gene expression profiles of all Hsp70 genes in Glaciozyma antarctica PI12 during a heat wave condition. In this study, we exposed G. antarctica PI12 cells to a realistic heat wave to understand the impacts of the extraordinary, unprecedented heat waves that hit Antarctica at nearly 40°C above the average in 2022. The experiment was carried out through eight days where cells were exposed gradually at 0, 2, 4, 8, 12, 16, 20, 25 and 30°C. The gene expression profiles were obtained during the simulated heat wave along with non-stressed control treatments by real-time PCR. Out of the six Hsp70 genes in G. antarctica PI12, five were expressed under the conditions tested. Among the expressed genes, gahsp70-1, gahsp70-5, and gahsp70-6 showed significant upregulation. Specifically, their expression levels increased by five- to eightfold after exposure to heat shock at 4°C. Gene expression patterns at 20°C and 30°C also showed induction with the highest at 3.6 folds and 5.8 folds, respectively. These results indicate that the expression of Hsp70 genes in G. antarctica PI12 was inducible under thermal stress, indicating their importance in cells during the heat waves. These results conclude that the gene expression patterns of Hsp70 during heat waves contribute vital information on thermal adaptation in the Antarctic marine ecosystem under climate stress.
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Authors and Affiliations

Nur Athirah Yusof
1
Jennifer Charles Labo
1
Wan Nur Shuhaida Wan Mahadi
1
Makdi Masnoddin
2
Hyun Park
3
Clemente Michael Vui Ling Wong
1
ORCID: ORCID

  1. Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
  2. Preparatory Centre for Science and Technology, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
  3. Division of Biotechnology, Korea University, Seoul 02841, Korea
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Abstract

Interpersonal interaction performance is significantly determined by group members’ personality traits. If a group lives in long-term isolation, the influence of personality traits on interpersonal interaction performance will be even stronger. The current study identified and examined the impact of the personality traits of the personnel living at the Ukrainian Antarctic Akademik Vernadsky station (N = 35) on their interpersonal interactions during long-term Antarctic expeditions. The results show that expeditioners’ personality traits significantly determined their interpersonal interactions. However, the influence of personality traits on different areas of interactions can vary significantly among different groups of expeditioners, even sometimes in diametrically opposite directions. The main reason for this is a formed microclimate specific to each group and corresponding group norms for formal and informal relations due to significant differences in personality traits that are characteristic of different groups’ participants. We determined that eleven indicators, out of a total of 23 examined personality traits, significantly differed among expeditioners from different groups (different expeditions). The study results can be used to enable better psychological selection of Antarctic expedition participants and to provide psychological support for these individuals.
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Authors and Affiliations

Oleg Kokun
1
ORCID: ORCID
Larysa Bakhmutova
2
ORCID: ORCID

  1. Directorate, G.S. Kostiuk Institute of Psychology of National Academy of Educational Sciences of Ukraine, Ukraine
  2. Scientific and organizational department, National Antarctic Scientific Center of Ministry of Education and Science of Ukraine, Ukraine
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Abstract

Soil-plant conditions in selected valleys typical for Bellsund Region are varying from hardly favourable (Skilvika), to favourable (Calypsostranda) and medium (Lyellstranda). Plant growth and development of a soil cover are favoured by grain size composition (loamy sands and light loams), quick warming-up of a soil, relative stability of a ground, location and shape of valleys, etc. Unfavourable soil-plant conditions result from too light or too heavy grain size composition, considerable dynamics of ground mechanical features and high compactness of a soil. Varying contents of carbonates and alkaline reaction (except for almost neutral reaction in organic horizons) were typical for the studied soils. Thickness of humus horizons as well as contents of organic C vary at the three studied sites. Significant is high concentration of easily available Ca and Mg, sometimes also of Na.

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Authors and Affiliations

Zbigniew Klimowicz
Stanisław Uziak
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Abstract

Mountain soils derived from massive rocks were studied in the northwestern Wedel Jarlsberg Land. Main soil properties were examined for collected samples. Soils were classified as lithosols with common loamy and silty composition, and small amount of colloidal fraction. Soils were mostly alkaline due to high content of CaCO3. Much more organic substance occurred at westerly- than easterly-exposed hills and located close to a sea. Examined soils contained much soluble forms of Ca, Mg and occasionally Na, little of P and K. Density of plant cover corresponded to contents of organic substance.

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Authors and Affiliations

Zbigniew Klimowicz
Jerzy Melke
Stanisław Uziak
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Abstract

Nematoda, Tardigrada, Rotifera and Crustacea composition in different freshwater habitats on Spitsbergen (Arctic) and King George Island (Antarctic) was presented. In all surveyed groups more genera and species were recorded from Spitsbergen than from King George Island. Habitats richest in taxa were moss banks and thaw ponds, whereas streams were poorest in species. In all groups in both regions cosmopolitan species dominated, but higher number of endemic species was recorded on King George Island. Regarding species composition in surveyed groups it can be suggested that freshwater habitats on Spitsbergen are more similar to each other than those on King George Island.

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Authors and Affiliations

Katarzyna Janiec
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Abstract

The highest infestation by phoronts (resting stages) of Apostoma ciliates forms 1, 2, is restricted to the 3-th and 4-th pairs of E. superba thoracic limbs. They occur mostly on meropodites of endopodite and plumose setae of exopodite. The trophonts (trophic stage) of those Apostoma are present in large numbers in krill's tissue. The life cycle of those histophagous Apostoma include also free-living stage - tomit. Swarm formed by krill seems to be a reason for the common and extensive infestation by protozoans.

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Authors and Affiliations

Ana Marija Stanković
Stanisław Rakusa-Suszczewski
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Abstract

A collection of 15 283 individuals of tanaidacean crustaceans was gathered by successive Polish Antarctic Expeditions in the years 1977-1993 in Admiralty Bay (King George Island, South Shetland Islands). Twelve species belonging to three families are identified in this study. The material is clearly dominated by Nototanais antarcticus (Hodgson, 1902); other common species were Nototanais dimorphus (Beddard, 1886) and Peraeospinosus sp. A. The highest density of tanaids was over 140 000 specimens m-2 , occuring on a muddy bottom in Herve Cove lagoon.

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Authors and Affiliations

Magdalena Błażewicz
Krzysztof Jażdżewski
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Abstract

Traps to catch microfauna transported by wind were installed on already colonised by plants area, in the vicinity of the glacier. After 6-week-exposition 859 individuals of microfauna were caught, of which Nematoda constituted 71%, Tardigrada 22% and Rotifcra 7%. Number of microfauna individuals caught depended on distance from the already colonised areas and presence of plant parts, together with which animals can be transported more easily. Microfauna connected with vegetation, which is transferred together with plant parts, was transported in higher numbers. Probably these taxa (i.e. Diphascon within tardigrades and Dorylaimidae within nematodes) colonise new habitats at first, but other species dominate later in freshwater bodies.

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Authors and Affiliations

Katarzyna Janiec
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Abstract

Luticola muticopsis is a characteristic species of polar and subpolar regions. Its morphological variability is not yet precisely described. In the investigated population the cells from capitate to shortened, flat rounded tips were observed. The range of dimensions of specimens was 8.8-40.6 μm x 5.5-17.6 μm, striae 11-22/10 μm; this range considerably exceeded that found in holotype diagnosis.

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Authors and Affiliations

Barbara Kawecka
Maria Olech
Maria Nowogrodzka-Zagórska
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Abstract

The Polish geological research on King George Island, South Shetland Islands (West Antarctica), during the two past decades (1977-1996) included: stratigraphy, radiometric dating, petrology and geochemistry, sedimentology and palaeoenvironmental studies, volcanology, tectonics, structural geology, Quaternary geology, paleobotany and palaeozoology. The major scientific achievements were: (1) the establishment of formal lithostratigraphic standards for radiometrically-dated Upper Cretaceous through Tertiary magmatic rock sequences and intercalated sediments; (2) the discovery of four Tertiary glaciations and three interglacials, spanning some 30 Ma from Early/Middle Eocene through Early Miocene; (3) the discovery and systematic elaboration of rich terrestrial and marine biota of Late Cretaceous through Early Miocene ages; (4) the reconstruction of changing Late Cretaceous and Tertiary terrestrial and marine palaeoenvironments in a mobile volcanic-arc setting; (5) the determination of age and structural evolution of the island's two Quaternary volcanoes; (6) the reconstruction of the Late Cretaceous through Recent evolution stages of the South Shetland magmatic arc and its backarc Bransfield Basin and Rift, based on tectonic and structural studies.

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Authors and Affiliations

Krzysztof Birkenmajer
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Abstract

A lichenicolous fungus, Dactylospora dobrowolskii Olech et Alstrup, new to science is described. The paper reports on 9 species of lichens and lichenicolous fungi collected in the Bunger Oasis (East Antarctica).

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Authors and Affiliations

Maria Olech
Vagn Alstrup
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Abstract

A year-round (3 March 1994 - 28 February 1995) phytoplankton study in Admiralty Bay revealed nanoplankton flagellates (< 20 μm) to be the major algae of the plankton, both in terms of cell numbers and carbon biomass. Their quantities fluctuated widely thoroughly the year showing several peaks, in May, April, December and January. Summer maximum of the group in December was mainly due to Cryptophyceae (4.9 x 106 cells l-1; 98.0 μg C 1-1) and Prasinophyceae (7.3 x 105 cells -1; 33.5 μg C -1). Diatoms were usually scarce (max. 6.8 x 105 cells -1; 7.82 p:g C 1-1) and were dominated by small species of Thalassiosira and by Nitzschia spp. (Pseudonitzschia); the domination structure somewhat differed from that observed in Admiralty Bay in the summer of 1977/78. Algal peaks were related to the surface water (4 m depth) temperature rise from +0.16 to +1.71˚C. Summer phytoplankton maxima were about 5-fold greater than those recorded in the summer of 1977/78.

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Authors and Affiliations

Elżbieta E. Kopczyńska
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Abstract

Comparison of T and S values in areas 1, 2, and 3 in the Bransfield Strait and Admiralty Bay (Fig. 1) shows that the warmest waters are found in area 1, while the coldest in area 3. Surface salinity is the lowest in area 2 as a result of water outflow from land. In area 3 vertical salinity variations are the lowest, with the maximum occurring at the surface. At 500 m depth the highest salinity is recorded in area 1. The most homogeneous distribution of temperature and salinity is observed in area 3. In Admiralty Bay, in the annual cycle of 1995 water temperatures at 4 m, 10 m and 100 m are similar to those in 1979 except in the winter, when they are lower.

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Authors and Affiliations

Stanisław Rakusa-Suszczewski
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Abstract

Epifaunal organisms (bryozoans, foraminifera, serpulid polychaetes, cirripeds, octocorals), scratch marks and borings (brachiopod pedicle attachment traces and gastropod, phoronid, sponge and algal boreholes) were recognized on the brachiopod shells from the Eocene La Meseta Formation of Seymour Island, Antarctic Peninsula. They are rare and occur only on about 10% of shells. It is probable that environmental conditions were not suitable for epibionts whose requirements were to be higher than those of brachiopods. The rarity of epifauna on the dead shells can be explained by their rapid burial.

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Authors and Affiliations

Maria Aleksandra Bitner
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Abstract

Complex analysis ofgeomorphological glacial processes in forefields of retreating glaciers in the southern Bellsund region was undertaken. Field studies and archival cartographic materials indicate continued glacial retreat, at least since the turn of the 19th and 20th centuries. Its average present rate of about 20 m/y is rather high and no moraine ridges are formed, except for the fluted moraines. Forefields of large glaciers are characterized by typical relief and sediments of frontal deglaciation only. Intensity and extent of glacial forefield remodelling depends mainly on activity ablation waters. At present glaciofluvial erosion predominates.

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Authors and Affiliations

Jan Reder
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Abstract

Temperature of superficial water in the Ezcurra Inlet was measured from March 1989 to February 1990, with a use of a mercurial thermometer with accuracy +0.1°C. Temperature was measured usually once a month at selected points. Influence of various factors on temperature of superficial water was preliminarily analysed. Basing on these results, temperature distribution in the mentioned area was determined. Mean yearly temperatures for each station, average space temperatures on measurement days and mean yearly temperatures for the whole area of the Ezcurra Inlet were calculated.

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Authors and Affiliations

Henryk Gurgul
Wiesław Stochmal
Wiesław Szymczak
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Abstract

The ostracod fauna were examined from the Kapp Starostin Formation sequences (Upper Permian) from West Spitsbergen (Svalbard). The ostracod taxa are mainly confined to 3 superfamilies: Kirkbyacea, Healdiacea and Bairdiacea. 11 taxa are identified. One new species, Kindlella bellsundi is proposed. The ostracod assemblage dominated by kirkbyacean taxa is related to open shelf marine environment.

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Authors and Affiliations

Ewa Olempska
Janusz Błaszyk
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Abstract

Thermoregulation is fully developed in 5 day old Wilson's storm petrels Oceanites oceanicus (Kuhl). Resting metabolic rate (RMR) and body temperature (Tb) of unattended 1- and 3-day old chicks continuously decrease at ambient temperature (Ta) of 5°C. After being heated the chicks return to normothermia. Ability to survive temporal deep hypothermia seems to be an adaptation to absence of parents and low temperatures in the nest during first days of life. After snow storm, during two days of starvation, chick RMR decreases by 40% at Ta of 0°C, but chick Tb is stable. This suggest decrease of thermal conductance (Ct). Fall of Ct may suggest beginning of hypohermia.

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Authors and Affiliations

Andrzej K. Gębczyński
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Abstract

Material for this paper was collected during the BIOMASS-SIBEX research programme, and consisted of 97 samples taken at 47 stations in Drake Passage and Bransfield Strait (Antarctica). The samples were taken by hauling Nansen nets vertically through the 0-100, 100 - 300 and 300 - 500 m layers at the end of December 1983 and the beginning of January 1984. Four Chaetognatha species were recorded in the study region: Eukrohnia hamata, Sagitta gazellae, Sagitta mari and Sagitta planctonis. The population structures of the dominant species E. hamata and also S. gazellae were analyzed in the context of the region's hydrology. Certain regularities are apparent in the distribution of the developmental stages of E. hamata in water column. Mature specimens of this species inhabit deeper waters than juveniles. The highest proportions of juveniles in the entire population of E. hamata were recorded in slightly warmer waters.

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Authors and Affiliations

Katarzyna Błachowiak-Samołyk
Luiza Bielecka
Maria I. Żmijewska

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