Search results

1

Short- and medium-chain fatty acids as a feed supplement for weaning and nursery pigs

100%

Szewczyk A., Hanczakowska E., Świątkiewicz M., Okoń K.

Polish Journal of Veterinary Sciences

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2013

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issue 4

2

A new method for identification of RTS noise

100%

Konczakowska A., Cichosz J., Szewczyk A.

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2006

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vol. 54

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issue 4

3

Intracellular ion channels: properties, function and experimental methodology

100%

Kicinska A., Debska G., Szewczyk A.

Postępy Higieny i Medycyny Doświadczalnej

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2000

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vol. 54

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issue 3

307-316

EN

Ion channels selective for potassium or chloride ions are present in membranes of intracellular organelles such as mitochondria, sarcoplastic (endoplastic) reticulum, nucleus, synaptic vesicles, and chromaffin, and zymogen granules. They are probably important in cellular events such as compensation of electrical charges during intracellular transport of Ca 2+ and H+ and regulation of organelle volume changes. This review describes the basic properties, and current hypotheses concerning the functional role, and some aspects of experimental methodology of intracellular ion channels studies.

4

Mitochondrial ion channels

88%

Debska G., Kicinska A., Skalska J., Berest V., Szewczyk A.

Postępy Higieny i Medycyny Doświadczalnej

|

2002

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vol. 56

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issue 3

315-321

EN

Ion channels selective for potassium or chloride ions are present in inner mitochondrial membranes. They are probably important in cellular events such as regulation of organelle volume changes. Additionally, mitochondrial potassium channels are targets for potassium channel openers and antidiabetic sulfonylureas. This review describes properties, and current hypotheses concerning the functional role of mitochondrial ion channels.

5

Comparative Studies of Surface Roughness of Thin Epitaxial Si Films by Computer Simulations and Experimental X-Ray and Optical Methods

88%

Żymierska D., Auleytner J., Domagała J., Szewczyk A., Dmitruk N.

Acta Physica Polonica A

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1997

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vol. 91

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issue 5

1025-1030

EN

The paper presents investigations of the surface roughness of epitaxial silicon films obtained by chemical vapour deposition with chloric and MOCVD processes. The flat surfaces of films and chemically etched surfaces of substrates were studied by optical methods as well as by X-ray reflectivity at grazing incidence. The computer simulations based on Fresnel theory were compared with the experimental results.

6

ATP-sensitive K+ transport in adrenal chromaffin granules

88%

Szewczyk A., Lobanov N. A., Kicinska A., Wojcik G., Nalecz M. J.

Acta Neurobiologiae Experimentalis

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2001

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vol. 61

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issue 1

1-12

EN

In the present study the influx of 86Rb+, a K+ analogue, was studied in mitochondria, microsomes and chromaffin granules prepared from adrenal gland medulla. The most active electrogenic 86Rb+ transport was found in the membrane fraction identified as chromaffin granules by marker enzyme estimation. The transport was found to be sensitive to ATP, ATPS, ADP and to the triazine dyes, but not to AMP and cAMP. The inhibition induced by ATP was observed in the absence of externally added Mg2+, suggesting that a free nucleotide, rather than the ATP-Mg complex, was required for inhibition. Furthermore, the 86Rb+ influx was found to be inhibited by Mg2+ alone, but not by Ca2+ and antidiabetic sulfonylureas. The 86Rb+ influx was not stimulated by potassium channel openers. In conclusion, our results indicate that an electrogenic, ATP-sensitive potassium transport system operates in the chromaffin granule membrane.

7

Magnetic and Transport Properties of R_3Cu_3Sb_4 Compounds (R = La, Ce, Pr, Nd, and Sm)

76%

Skolozdra R., Baran M., Horyn A., Szewczyk A., Gorelenko Y., Szymczak H., Szymczak R.

Acta Physica Polonica A

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2002

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vol. 102

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issue 3

429-435

EN

Magnetic susceptibility, electrical resistivity, and thermopower of the series of the R_3Cu_3Sb_4 compounds (R=La-Sm) were measured over the temperature ranges 1.9-300 K (susceptibility and resistivity) and 80-370 K (thermopower). Below 25 K, resistivity of these compounds grows exponentially with decreasing temperature. For some compounds, R = Ce, Sm, a maximum on temperature dependence of resistivity is observed. Ce_3Cu_3Sb_4 compound undergoes a magnetic transition at 12 K.

8

Isulfhydryl reagents with K+ transport in adrenal chromaffin granules

76%

Szewczyk A., Lobanov N. A., Nowotny M., Nalecz M. J., Berent U., Mroczkowska J. E., Nalecz K. A.

Acta Neurobiologiae Experimentalis

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1997

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vol. 57

|

issue 4

329-332

EN

In the present study the functional role of SH groups in the Ca2+ -independent K+ selective channel activity in the membrane of bovine adrenal gland chromaffin granules has been studied. Ionic channel activity has been estimated using 86Rb+, a K+ analogue, flux measurements. The inhibition of chromaffin granules K+ channel by SH modifying agents, such as N ethylmaleimide, mersalyl and phenylarsenoxide, is described.

9

Influence of Co Doping on Crystal and Magnetic Properties of Gd_2Cu_2In

76%

Gondek Ł., Szytuła A., Kaczorowski D., Szewczyk A., Gutowska M., Tyvanchuk Y., Kalychak Y.

Acta Physica Polonica A

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2012

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vol. 122

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issue 1

216-219

EN

Physical properties of Gd_2Cu_{2 - x}Co_{x}In (x = 0.1, 0.2, 0.3) samples are investigated. The paper brings results of X-ray diffraction, magnetometric as well as specific heat studies. It was found that only sample with x = 0.1 exhibits desired crystal structure. Other compositions show existence of impurities due to lack of dissolution Co atoms. For Gd_2Cu_{1.9}Co_{0.1}In sample the Curie temperature of 92.5 K was evidenced. Thus, an enhancement of ferromagnetic correlations with comparison to Gd_2Cu_2In sample was evidenced. It was found that Gd_2Cu_{1.9}Co_{0.1}In sample exhibits magnetocaloric effect within broad temperature range.

10

La_{0.7}Sr_{0.3}MnO_3 Thin-Film Grain-Boundary Junctions on a Bi-Crystal Substrate

76%

Gierłowski P., Szewczyk A., Abal'oshev A., Vlakhov E., Donchev T., Blagoev B.

Acta Physica Polonica A

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2004

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vol. 106

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issue 5

715-719

EN

Transport properties of 10μm to 30μm wide grain-boundary junctions ion-etched in thin colossal magnetoresistance La_{0. 7}Sr_{0.3}MnO_3 films deposited on a SrTiO_3 bi-crystal were investigated. We have measured the current-voltage characteristics in the temperature range from 4.2 K to 300 K without applied magnetic field, as well as the magnetoresistance at magnetic fields up to±10 kOe directed parallel to the film surface, both perpendicular and parallel to the direction of current flow through the junctions. The investigated junctions have nonlinear current-voltage characteristics in this temperature range and consist of several magnetic domains. The maximum magnetoresistance (R(H)-R _{max})/R_{max}, measured at 1 kOe was -17.6% at 4.1 K.

11

Structure and Magnetism of MBE-Grown Co/Cu Multilayers

76%

Baczewski L. T., Wawro A., Domagała J., Pełka J., Szewczyk A., Nabiałek A.

Acta Physica Polonica A

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1997

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vol. 91

|

issue 2

315-319

EN

Structural and magnetic properties of Co/Cu multilayers deposited in the ultra-high vacuum molecular beam epitaxy system on glass substrates with different modulations periods were investigated. A structural characterization was performed by means of RHEED and Auger spectroscopy (in situ), small angle X-ray reflectivity and scanning tunneling microscopy. The samples obtained have a textured, polycrystalline layered structure for deposition at room temperature. Magnetization and in-plane magnetoresistance measurements were performed as a function of Cu and Co layer thicknesses. An influence of different buffers and of interface quality on magnetic properties was investigated.

12

Structural, Magnetic and Transport Properties οf NdBaCo_{2}O_{5+x} Thin Films Deposited by Magnetron Sputtering

64%

Vlakhov E., Szymczak R., Baran M., Piotrowski K., Szewczyk A., Paszkowicz W., Lobanovskii L., Matyajasik S., Nenkov K., Szymczak H.

Acta Physica Polonica A

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2009

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vol. 115

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issue 1

89-91

EN

For the first time, thin films of NdBaCo_{2}O_{5+x} were deposited by RF magnetron sputtering on different substrates. The films deposited on SrLaAlO_4(001) substrates exhibited highly textured structure with c-axis directed out-of-plane. Magnetic measurements M vs. T of three NdBaCo_{2}O_{5+x}/SrLaAlO_4(001) films revealed successively paramagnetic-ferromagnetic-antiferromagnetic transitions with decrease in temperature. Their paramagnetic Curie-Weiss temperatures were estimated to be in the range of T_{C}=100-116 K. Resistivity of the cobaltite thin film exhibited insulating behavior and the best fit was found for the variable range hopping mechanism.

13

Manifestation of Spin-Glass-Like Behavior in the Organometallic Magnet

64%

Dyakonov V., Arciszewska M., Dobrowolski W., Szewczyk A., Szymczak H., Aksymentieva E., Varyukhin V., Zubov E., Gutowska M.

Acta Physica Polonica A

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2000

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vol. 97

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issue 5

863-866

EN

Ac susceptibility (χ_{ac}) and dc magnetization (M_{dc}) of the organometallic magnet Na[FeO_{6}(C_{10}H_{8}N)_{3}] have been studied in temperature range of 4.2-200 K, in an external magnetic field up to 16 kOe. Some peculiarities of the χ_{ac} and M _{dc} behavior, which are characteristic of spin-glasses, e.g. cusps in the susceptibility and zero-field-cooled magnetization, an irreversibility between the field-cooled and zero-field-cooled magnetization and dependences of the T_{cusp} temperature on the frequency and the intensity of the magnetic field, were observed at low temperatures.

14

Atomic Order and the Interaction of Electronic and Magnetic Subsystems in Epitaxial LaSr(Ca)MnO Films

64%

Okunev V., Samoilenko Z., D'yachenko T., Abal'oshev A., Baran M., Gierłowski P., Lewandowski S., Szewczyk A., Szymczak R.

|

EN

We have investigated the structure, and electric, optical, and magnetic properties of LaSr(Ca)MnO films containing atomic clusters of various types coherently built into the basic crystallographic matrix. Below the transition to the metallic state, the electrical conductivity of the films is determined by tunneling of charge carriers between metallic clusters. We have found that for each sample there exists a threshold value of magnetic ordering, above which the magnetic subsystem starts to affect actively the film conductivity. The observed increase of conductivity with decreasing temperature is caused by the fact that in the process of magnetic ordering of the samples the cluster size and concentration of metallic phase increase. Experimental results are in agreement with theoretical calculations.

15

Crystalline Structure of Potassium Holmium Double Tungstate

46%

Borowiec M., Dyakonov V., Woźniak K., Dobrzycki Ł., Majchrowski A., Michalski E., Zubov E., Khatsko E., Zayarnyuk T., Szewczyk A., Gutowska M., Rykova A., Barański M., Domukhovski V., Shtyrkhunova V., Iwanowski P., Żmija J., Szymczak H.

Acta Physica Polonica A

|

2011

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vol. 119

|

issue 6

835-837

EN

The potassium holmium double tungstate was prepared by using top seeded solution growth technique. Structural investigations have been performed at room temperature. The KHo(WO_4)_2 single crystal belongs to the monoclinic space group C2/c with the unit-cell parameters: a = 10.624(2) Å, b = 10.352(2) Å, c = 7.5434(15) Å, β = 130.78(3)^{o}, and Z = 4. The atomic coordinates, isotropic and anisotropic displacement parameters and interionic distances for the studied structure were determined.

Refine search results

Short- and medium-chain fatty acids as a feed supplement for weaning and nursery pigs

A new method for identification of RTS noise

Intracellular ion channels: properties, function and experimental methodology

Mitochondrial ion channels

Comparative Studies of Surface Roughness of Thin Epitaxial Si Films by Computer Simulations and Experimental X-Ray and Optical Methods

ATP-sensitive K+ transport in adrenal chromaffin granules

Magnetic and Transport Properties of R_3Cu_3Sb_4 Compounds (R = La, Ce, Pr, Nd, and Sm)

Isulfhydryl reagents with K+ transport in adrenal chromaffin granules

Influence of Co Doping on Crystal and Magnetic Properties of Gd_2Cu_2In

La_{0.7}Sr_{0.3}MnO_3 Thin-Film Grain-Boundary Junctions on a Bi-Crystal Substrate

Structure and Magnetism of MBE-Grown Co/Cu Multilayers

Structural, Magnetic and Transport Properties οf NdBaCo_{2}O_{5+x} Thin Films Deposited by Magnetron Sputtering

Manifestation of Spin-Glass-Like Behavior in the Organometallic Magnet

Atomic Order and the Interaction of Electronic and Magnetic Subsystems in Epitaxial LaSr(Ca)MnO Films

Crystalline Structure of Potassium Holmium Double Tungstate