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1
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Influence of oxygen conditions on the yield and mineral composition of triticale cv.Jago

100%
Przywara G., Stepniewski W., Stepniewska Z., Brzezinska M., Wlodarczyk T.
International Agrophysics
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2001
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tom 15
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nr 4
2
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Determination of the integration range in voltammetric measurements of oxygen flux in the soil with the use of two- and three-electrode systems

100%
Bieganowski A.
International Agrophysics
|
2004
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tom 18
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nr 4
3
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Temporal and spatial evolution of the Baltic deep water renewal in spring 2003

100%
Feistel R., Nausch G., Matthaus W., Hagen E.
Oceanologia
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2003
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tom 45
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nr 4
In January 2003, a deep-water renewal process in the Baltic Sea commenced with an inflow of about 200 km3 of cold and well oxygenated water from the Kattegat, half of which was of salinity >17 PSU; it is considered to be the most important inflow since 1993. Related front propagation and the ventilation of anoxic waters between the western and the central Baltic were recorded by the Darss Sill measuring mast, the Arkona Basin buoy, a subsurface mooring in the Eastern Gotland Basin, and hydrographic research cruises conducted in January, February, March, May and August 2003. Already in May, the central Gotland Basin was reached by water with near-bottom oxygen concentrations among the highest ever recorded there. A comprehensive review of the observed spatial and temporal structures together with additional background data is presented. Estimates of the intensity of the present inflow are discussed.
4

Chironomidae [Diptera] community response to improved oxygen conditions in a naturally recovering lake [Lekuk Wielki, Northeast Poland]

84%
Koszalka J.
Oceanological and Hydrobiological Studies
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2009
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tom 38
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nr 2
83-89
5

The modulation of HIFs, pluripotency and differentiation genes expression by oxygen conditions in neural stem cells derived from human cord blood

84%
Szablowska-Gadomska I., Drela K., Podobinska M., Ziemka-Nalecz M., Domanska-Janik K., Buzanska L.
Acta Neurobiologiae Experimentalis
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2013
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tom 73
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nr 1
The oxygen tension is an important factor modulating cell fate and developmental decisions. There are evidences that HIFs (Hypoxia Inducible Factors) family is implicated in the regulation of pluripotency and differentiation genes. The goal of this study is to compare the influence of close to physiological oxygen conditions (5%) to atmospheric oxygen tension on differentiation process and pluripotent activity in HUCB-NSC. The expression of Hypoxia Inducible Factors, stemness and neural differentiation markers in NSC, cultured under 5% and 21% oxygen were checked on the transcriptional and translational level. We were looking at the interaction between HIFs (HIF1 alpha, HIF 2 alpha) and activity of neural differentiations genes (MAP2, GFAP, β-tubulin) as well as expression of pluripotency genes (Oct4, Sox2, Rex1 and Nanog). In order to demonstrate the impact of increased HIF1α and/ or HIF2α level on cell differentiation we used DMOG (Sigma) which is of prolyl-4-hydroksylase inhibitor to increase HIF alpha levels. Our data show, that low oxygen conditions promote proliferation of HUCBNSC at early stage of development and can activate Oct4 and Nanog genes in HUCB-NSC. The time of cultivation of the cells in low oxygen conditions and the developmental stage of the cells are the important factors for the induction of the expression of “pluripotency” genes.Hypoxia Inducible Factors HIF 1α and HIF 2α, but not HIF3α are expressed in HUCB-NSC at all stages of development. During neuronal differentiation of HUCB-NSC by using dBcAMP, 5% oxygen level act synergistically, promoting further differentiation (enhanced MAP2 expression). Application of prolyl hydroxylase inhibitor – DMOG resulted in increased expression of HIF1α but not HIF2α and increased the expression of MAP2 (only in 21% oxygen conditions) referring to variants without DMOG. Sponsored by grant from Polish Ministry of Scientific Research and Higher Education No N N302 597838 and by NSC grant No 2011/01/B/NZ3/05401
6
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The role of alternative oxidase in hypoxic metabolism of nitric oxide

84%
Igamberdiev A., Shah J., Cochrane D., Gupta K., Vanlerberghe G.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
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2013
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tom 94
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nr 2
7
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Diurnal variations in nitrogen, phosphorus and iron compounds in the Southern Baltic Sea

84%
Sikorowicz G., Falkowska L., Burska D., Dunajska D., Pryputniewicz D., Magulski R., Lewandowska A.
Oceanologia
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2005
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tom 47
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nr 2
In order to assess their short-term variability, nutrient concentrations were measured at standard depths at 2 h intervals in the deepest region of the Gdańsk Deep during the first ten days of June 2001. The mean concentrations of nutrients in the euphotic zone were: NN (NO2 −, NO3 −, NH4 +) – 1.93 μmol dm−3, PO4 3− – 0.12 μmol dm−3 and Fetot – 0.11 μmol dm−3. During daylight hours, when the rate of assimilation was fastest, concentrations of nitrogen, phosphorus and iron compounds were very low. The phosphate concentration fell to a minimum (0.03 μmol dm−3) between 04:00 and 10:00 hrs, while total iron dropped to 0.01 μmol dm−3 between 10:00 and 16:00 hrs. Both levels were below the limiting values for phosphorus and iron. At night, concentrations of NO3 − and PO4 3− rose by 25%, those of NH4 + and Fetot by 35%. The mean molar ratios of NN:PO4 3− and Fetot:PO4 3− in the surface layer were subject to significant daily fluctuations. The molar NN:PO4 3− ratio was higher than the optimum value established for the Baltic Sea. Below the halocline, the concentrations of dissolved iron and phosphorus rose as a result of diffusion from sediments in response to changing redox conditions.
8

Vertical distribution of dominant cyanobacteria species in three lakes - evidence of tolerance to different turbulence and oxygen conditions

84%
Wojciechowska W., Poniewozik M., Pasztaleniec A.
Polish Journal of Ecology
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2004
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tom 52
|
nr 3
The composition and abundance of cyanobacteria in three lakes of the Polesie Lubelskie (East Poland) were studied in summer periods. Vertical distribution of these algae was analysed in two depths – in epilimnion and deoxygenated metalimnion. Species composition and domination was similar for these two sites. It means that the species like: Limnothrix planctonica (Wołosz.) Meffert, Limnothrix redekei (Van Goor) Meffert, Planktothrix agardhii (Gom.) Anagn. et Kom., Woronichinia naegeliana (Unger) Elenk. and Microcystis viridis (A. Braun in Rabenhorst) Lemm. are not affected by turbulence of water as well as by oxygen conditions.
9
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Evidence for a warm water inflow into the Baltic Proper in summer 2003

84%
Feistel R., Nausch G., Heene T., Piechura J., Hagen E.
Oceanologia
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2004
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tom 46
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nr 4
The exceptional warm water inflow into the Baltic Sea in summer 2002, which preceded the major Baltic inflow of January 2003, was surprisingly repeated in modified form in summer 2003. Its warm waters even replaced the renewed, cold inflow waters in the eastern Gotland Basin and commenced another warm period in its deep layers, where the previous one had lasted from 1997 to 2003. Details of the temporal and spatial behaviour of this new baroclinic inflow are presented from various measurements carried out from the Kiel Bight up to Gotland, covering the Darss Sill, the Arkona, Bornholm, Gdańsk Basins and the Słupsk Channel, focused mainly on the time period between July 2003 and July 2004. Hypothetically, the repetition of these exceptional warm inflow events could be regarded as a possible regional indicator for global climatic change.
10
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Warm waters of summer 2002 in the deep Baltic Proper

84%
Feistel R., Nausch G., Mohrholz V., Lysiak-Pastuszak E., Seifert T., Matthaus W., Kruger S., Hansen I. S.
Oceanologia
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2003
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tom 45
|
nr 4
From October 2002 until March 2003 surprisingly warm, oxygenated waters were frequently encountered in the Baltic Sea in the area between the Bornholm and Fårö Deeps from the halocline down to the bottom. Owing to their ventilation effect in the stagnating deep waters, their occasional observations have partly been incorrectly attributed to the inflow events of October 2002 or January 2003. The emergence of some of these waters can be traced back to the exceptional summer weather conditions in August and September 2002 in central Europe. The warm waters played a remarkable renewal pacemaker role for the subsequent important winter inflow of January 2003. The evolution of this summer inflow is described and possible causes are discussed.
11

Chemism of bottom sediments from a lake treated with various restoration techniques

67%
Tandyrak R.
Electronic Journal of Polish Agricultural Universities. Series Environmental Development
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2005
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tom 08
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nr 4
12

Assessment of the multi-directional experiment to restore Lake Goreckie (Western Poland) with particular focus on oxygen and light conditions: first results

67%
Sobczynski T., Joniak T., Pronin E.
Polish Journal of Environmental Studies
|
2012
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tom 21
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nr 4
Our paper presents the study results of the first year of restoration of Lake Góreckie in Wielkopolska National Park. The restoration was carried out on several levels which involved: aeration of the hypolimnion using the pulverizing aerator with wind drive, phosphorus inactivation by iron coagulant, and reduction of plankton-eating fish. The comparison of the results obtained in the year 2010, that is in the time of the implementation of restoration procedures, with the results of similar studies conducted before the restoration, in 2008 revealed an increase in water transparency that resulted in the greater range of visible radiation from the photosynthetically active scope, which unfortunately did not improve the oxygen condition in the water depth. The effects of the hypolimnion aeration were not observed, even at the sampling station situated 20 m from the aerator. In the sub-bottom zone, the decrease in phosphate concentration was observed, with the concentration of ammonium nitrogen staying at the same level, which indicates the effectiveness of phosphate precipitation.
13

Oxidation-reduction conditions in the bottom sediments of Puck Bay

67%
Bolalek J., Kowalewska M.
Oceanological Studies
|
1997
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tom 26
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nr 2-3
14

The technology for reduction of fishes suffocation during winter period on example of Dnieper reservoirs

67%
Timchenko V. M., Timchenko O. V.
International Journal of Ecohydrology and Hydrobiology
|
2001
|
tom 01
|
nr 3
The two ways of modification the oxygen conditions of dam reservoirs in order to protect fish from suffocation at freezing periods were presented: 1) the ice-hole size enlargement, and 2) short-term rises of a water level to raise oxygen concentration in the waters in fishes wintering sites. Both the methods are based on the modifications of the water flow through hydroelectric power stations as the only management tool. The mathematical formulae for calculating water flows and its effects are presented, as well as examples of calculation for January and February for Kremenchuk Reservoir (Dnieper River).
15

Impact of limited water flow in a pipeline on the thermal and oxygen conditions in a lake restored by hypolimnetic withdrawal method

67%
Dunalska J.
Polish Journal of Environmental Studies
|
2003
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tom 12
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nr 4
Lake Kortowskie was studied during water stagnation, when it is subjected to bottom water withdrawal to outflow through a pipeline. The examinations were carried out after flow reduction from 0.25 m3· s-1 to about 0.05 m3· s-1. It has been revealed that hypolimnion withdrawal has much more effect on the temperature and oxygen content in the water body. Destruction of the thermal settings and the rate of oxygen depletion oc-curs with variable intensity, depending on the amount of water withdrawn by the pipeline. In the period of limited hypolimnion withdrawal the temperature increase near the bottom was slower (by 0.2°C on average in 10 days) than in the period of the pipeline’s maximal capacity (i.e. 0.5-0.8°C).
16
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Agroekologiczne aspekty warunkow tlenowych gleb ornych

51%
Glinski J., Stepniewski W., Stepniewska Z., Ostrowski J., Wlodarczyk T., Brzezinska M.
Acta Agrophysica
|
2000
|
tom 32
1-87
Monografia zawiera 41 rysunków i 18 tabel. Przedstawia ona różne aspekty agroekologicznej roli tlenu w glebach ornych. Jest oparta o przegląd 73 pozycji literatury oraz własne osiągnięcia autorów tej monografii. Problematyka monografii dotyczy: Uwarunkowań stanu natlenienia gleb; Wskaźników natlenienia gleb; Wpływu stanu natlenienia na procesy glebowe i na rośliny; Przestrzennej charakterystyki właściwości oksydoredukcyjnych gleb ornych Polski; Przykładów kompleksowej charakterystyki aeracyjnych właściwości niektórych gleb ornych Europy Centralnej; Nowych aspektów standaryzacji glebowych parametrów natlenienia oraz miejsca stanu aeracji gleb w oksygenologii; Znaczenia wskaźników odporności gleb na redukcję t3oo • t400 dla praktyki rolniczej i melioracyjnej; Propozycji dalszych badań nt. agroekologicznych aspektów natlenienia gleb.
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