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1
Content available remote

Iron-Boron Pair in Silicon: Old Problem Anew

100%
Dobaczewski L., Surma M.
Acta Physica Polonica A
|
1996
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vol. 90
|
issue 4
613-622
EN
For the iron-boron pair in the p-type silicon two different configurations of the defect are observed: stable and metastable. The reported metastable configuration is the first step in a dissociation process of the stable, i.e. of trigonal symmetry, configuration of the pair. Rate equations for the two-step iron-boron pair dissociation allowed us to evaluate the dissociation rates for both configurations of the pair. The driving force for the creation and, then, dissociation of the metastable pair is the minority carrier injection followed by the electron-hole recombination process in the space charge region. A use of the high-resolution Laplace-transform deep level transient spectroscopy allowed us to demonstrate for both of the configurations the influence of the magnetic field on the hole emission.
2
Content available remote

Efficient Two-Center Auger Mechanism of Electron Trapping by Fe^{3+} Ions in ZnSe:Fe,Cr

100%
Surma M., Godlewski M.
Acta Physica Polonica A
|
1997
|
vol. 92
|
issue 5
1017-1020
EN
A detailed analysis of decay kinetics of light induced electron spin resonance signals of Cr^{1+} and Fe^{3+} ions in ZnSe:Fe,Cr is given. We observe that the Cr^{1+} electron spin resonance signal decays once free electrons are thermally ionized from shallow donors of ZnSe. Such unusual behavior of the Cr^{1+} electron spin resonance signal is explained by efficient two-center Auger recombination: the Cr^{1+} center is ionized due to the Auger-type energy transfer from the electron being trapped by the Fe^{3+} ion. Such process is shown to be consistent with the temperature dependence of the decay times of electron spin resonance signals. Its quantum efficiency is estimated to be as large as 18% for Cr and Fe concentrations which were studied.
3

Barley haploid from reciprocal crosses of Hordeum bulbosum (2x) and H.Vulgare (2x)

100%
Surma M., Adamski T.
Journal of Applied Genetics
|
1995
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vol. 36
|
issue 1
11-16
EN
Results of crosses between Hordeum bulbosum (2x) and H.vulgare (2x) are presented.Nine H.vulgare genotypes of different crooability with H.bulbosum were treated both as female and male parents Immature embryos were cultured in vitro according to Adamski and Surma (1994).Seeds set, embryo development and obtained haploid plants were recoded.It was shown that seed setting and haploid plant efficiency (haploids/100 florets) were about ten times lower in H.bulbosum x H.vulgare than H.vulgare x H.bulbosum.The cvs.Vada, Apex and the doubled haploid line KA7/3 (related to Apex) which showed a low crossability in H.vulgare x H.bulbosum,gave a relatively high seed setting in reciprocal crosses.The obtained results indicte that partial incompatibility of some H.vulgare genotypes with H.bulbosum could be cytoplasmatically influenced.
4

The influence of genotypes on production of barley haploids with Hordeum bulbosum cytoplasm

100%
Adamski T., Surma M.
|
EN
Hordeum bulbosum (2x) was crossed to H.vulgare (2x) to estimate the influence of genotypes on production of barley haploids with H.bulbosum cytoplasm.Four H.bulbosum clones were pollinated with 11 H.vulgare cultivars and doubed haplod lines.Immature embryos were cultured on the B5 medium (Gamborg et al.1968).Seed setting, embryo differentiation, haploid plant development and haploid plant efficiency were scored and computed using multivariate analysis of variance as well as cluster and canonical variable analysis.Only the influence of H.vulgare genotypes on haploid production appeared to be significant.Haploid plant efficiency was very low (average 1.45%) and depended mainly on seed setting.Obtained barley haploids and consequently, doubled haploid lines with alien cytoplasm can constitute precise material for genetic studies dealing with cytoplasmic inheritance.
5

The use of laser light for obtaining barley haploids by Hordeum bulbosum method

81%
Rybinski W., Surma M., Adamski T.
Biotechnologia
|
2001
|
issue 1
143-147
EN
The effect of helium-neon laser with wavelength of 632 nm on seed setting in a cross of Hordeum vulgare x H. bulbosum was studied. The seeds before sowing as well as immature embryos were irradiated with laser light. Material not irradiated with laser beams constituted the control. It was shown that stimulative dose of laser beams increased the number of seeds/100 pollinated florets in comparison with the control combination. After laser treatment, the seed setting of the line HG156, and cultivars Vada and Apex was higher by 13.0, 7.9 and 3.2%, respectively. The number of obtained haploids/100 cultured embryos irradiated with laser light was also higher in comparison with the control by 1.8, 0.9 and 10.8%, respectively. The obtained results show that treatment with laser beams was more effective at the first step of haploid production (seeds/100 florets) than at the next step (haploids/100 embryos cultured). From the practical point of view, better results can be obtained by irradiation of seeds before sowing than by irradiation of immature embryos. Cultivar Apex with a positive reaction on irradiation of embryos was an exception here.
6
Content available remote

Magneto-Optical Characteristics of Human Serum

81%
Surma M., Bućko J., Bąk G., Ciszek M.
Acta Physica Polonica A
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2000
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vol. 98
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issue 5
533-542
EN
A study of magneto-optical circular birefringence of human serum from healthy subjects and cancer patients was performed. Significant differences in the magnetic field induced change of the natural optical activity of serum from healthy blood donors and neoplasmic patients were noted. The natural optical activity of blood is positive, irrespective of the donor health status, whereas the magnetic field induced (B > 10T) change in the natural optical activity of the serum from cancer patients is negative while that from healthy donors is positive. The value and sign of the characteristic magneto-optical marker of human serum was discovered in a study of the influence of very high magnetic fields on chiral media and interpreted on the basis of the recent developments in the theory of magnetic field induced optical circular birefringence in the media revealing natural optical activity. The blood serum is a chiral medium.
7
Content available remote

Electron Spin Resonance Studies of Te Doped AlGaAs Epilayers

81%
Surma M., Godlewski M., Żytkiewicz Z.
Acta Physica Polonica A
|
1992
|
vol. 82
|
issue 5
817-820
EN
Results of electron spin resonance studies of tellurium doped AlGaAs epilayers are presented. We demonstrate a new approach to the studies of shallow donor-deep DX level transformation upon illumination or with an increase in temperature. The processes can be monitored by observing the changes of magnitude of an unidentified ESR signal of AlGaAs.
8
Content available remote

Nature of Blue Anti-Stokes Luminescence in ZnSe:Cr

81%
Ivanov V. Y., Semenov Y. G., Surma M., Godlewski M.
Acta Physica Polonica A
|
1995
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vol. 88
|
issue 4
743-746
EN
The mechanism of the anti-Stokes photoluminescence in ZnSe:Cr is dis­cussed. It is shown that the two-step ionization transitions of Cr(2^{+} ↔ 1^{+}) result in appearance of the blue anti-Stokes photoluminescence of ZnSe:Cr. There are also some indications that the Auger type co-operative process can contribute to the photoluminescence excitation.
9
Content available remote

Transition Metal-Related Centres in Silicon Studied by High-Resolution Deep Level Transient Spectroscopy

81%
Dobaczewski L., Kamiński P., Kozłowski R., Surma M.
Acta Physica Polonica A
|
1995
|
vol. 88
|
issue 4
703-706
EN
High-resolution Laplace-transform deep level transient spectroscopy tech­nique has been used to study a fine structure in the carrier emission process for transition metal- and thermal donors-related defects in silicon. For the case of the transition metal centres the method revealed the fine structure when the defect has a similar emission characteristics to other defects in the crystal. The method also demonstrated the complex emission process for the thermal donors.
10

A simple test for detection of linkage

81%
Surma M., Kaczmarek Z., Adamski T., Kaczmarek.
Journal of Applied Genetics
|
2002
|
vol. 43
|
issue 2
171-174
EN
The paper presents a proposition for detection of linkage of genes responsible for metrical traits. Taking into account the expected means for early generations (F1, F2, F3) and a population of homozygous lines (in this case doubled haploid lines, DH derived from a cross between two homozygous parents) as well as estimators of genetic parameters m, [d], [i], [h] and [l], the expected values for these parameters in the presence of linkage have been formulated. It was found that when there is no linkage, the expression F1 ? 6F2 + 8F3 ? 3DHmean is equal to zero. Thus, an experiment covering DH lines and F1, F2, F3 hybrids makes it possible to obtain, beside information of interest, also information on presence or absence of linkage.
11

Theoretical bases for detection of linkege of genes between two quantitative characters in the presence of nonallelic interaction

81%
Kaczmarek Z., Surma M., Adamski T.
Genetica Polonica
|
1994
|
vol. 35
|
issue 1-2
53-62
12
Content available remote

ESR Study of the Magnetic Properties of the CdTe/CdMnTe Multi Quantum Wells

81%
Surma M., Godlewski M., Waag A.
Acta Physica Polonica A
|
1993
|
vol. 84
|
issue 3
543-546
EN
The results of electron spin resonance investigations of bulk Cd_{1-x}Mn_{x}Te and of molecular beam epitaxy grown CdTe/CdMnTe single 2 μm thick layer and multi quantum well with Mn concentrations of about x = 0.10 are compared. The Mn^{2+} electron spin resonance spectrum of the MQW CdTe/CdMnTe shows several features different from those observed in the CdMnTe bulk sample. The Mn^{2+} resonance shows a small anisotropy of position and width with the anisotropy axis normal to the heterointerface. The temperature dependence of the width of the electron spin resonance line is also different from that observed for the bulk and for the thick single layer.
13
Content available remote

Fe^{2+} → Fe^{3+} Ionization Transition in ZnSe

81%
Surma M., Godlewski M., Surkova T.
Acta Physica Polonica A
|
1993
|
vol. 84
|
issue 3
547-550
EN
Detailed photo-ESR study of iron and chromium impurities in ZnSe is presented. The energy level position of Fe 2+/3+ energy level is determined. The role of iron and chromium impurities in nonradiative recombination processes is discussed.
14

Methods to predict transgressive segregation in barley and other self-pollinated crops

81%
Kuczynska A., Surma M., Adamski T.
Journal of Applied Genetics
|
2007
|
vol. 48
|
issue 4
321-328
EN
Most of agronomically important characters are biometric traits. An improvement of these traits in cultivated plants by deriving segregants superior to parents, which could be developed as cultivars, is a main goal in breeding of self-pollinated crops. Two problems need to be solved: when will the progeny be better than its parents and how can a genetic potential of a given pair of parental genotypes be predicted? In this paper, transgressive segregation in homozygous barley populations is shortly reviewed. Various approaches to choosing parental forms are shown, and a theoretical method for predicting the frequency of transgressive segregants in a homozygous population is presented. Additionally, relationships between parental diversity estimated with molecular markers and the progeny performance are discussed. Although the prediction of transgressive segregation is still a problem, it seems promising to apply an approach measuring the performance of the parental genotypes and estimating their genetic distance by molecular markers.
15
Content available remote

Photo-ESR Studies of Ni doped ZnS and ZnSe

81%
Surma M., Zakrzewski A., Godlewski M., Surkova T.
Acta Physica Polonica A
|
1995
|
vol. 87
|
issue 1
221-224
EN
The results of electron spin resonance experiments are presented for nickel doped ZnS and ZnSe. Energy level position of Ni^{1+} state in band gap of ZnS and ZnSe is determined. The nonradiative recombination processes of donor-acceptor pairs in Ni doped samples are discussed.
16

Numerical method for detection of linkage between genes for two metrical traits

81%
Kaczmarek Z., Surma M., Adamski T., Czajka S.
Journal of Applied Genetics
|
2004
|
vol. 45
|
issue 1
27-35
EN
A homozygous population derived from hybrids between two homozygous parents may be used for genetic analysis of metrical traits. The paper describes the use of doubled haploids (DH) and single seed descent (SSD) lines for detection of linkage between genes conditioning two quantitative traits. A computational algorithm is presented, which facilitates matching various variants of relations between variances, covariances and means of DH and SSD populations so as to make it possible to conclude on the presence/absence of linkage. The suggested methodology is illustrated with an example concerning three quantitative traits of barley: length of the third internode, stem wall thickness, and 1000-grain weight.
17

Frequency of transgression and gene distribution in barley doubled haploid populations from first and second cycle hybrids

81%
Surma M., Adamski T., Kaczmarek Z., Kapala A.
Journal of Applied Genetics
|
1998
|
vol. 39
|
issue 3
237-247
EN
Barley doubled haploids (DH) derived from first and second cycle hybrids were investigated in field experiments. Parental lines designed for the second cycle hybrids were three doubled haploids from the first cycle hybrids, which were observed to have the highest grain yield. Yield structure characters, crude protein content and protein fractions were analysed. Phenotypic and genetic variability and the frequency of transgression in the studied populations were calculated. For the studied traits additive, [d], and epistatic [i], effects as well as coefficient of gene dispersion were estimated. It was found that the phenotypic and genetic variability of DH populations derived from second cycle hybrids was higher than that of the original population for all the studied traits except grain yield. A greater proportion of transgressive lines than in the original population was also observed in populations from second cycle hybrids. Only one DH line exceeding the high yielding parent was found among 141 lines under study. The relationship between the frequency of transgressions and gene dispersion was recorded: the greatest number of transgressive lines occurred in those traits for which the dispersion was observed.
18
Content available remote

Influence of Magnetic Field on Blue Anti-Stokes Luminescence of ZnSe:Cr Crystals

81%
Ivanov V., Semenov Y. G., Surma M., Godlewski M.
Acta Physica Polonica A
|
1996
|
vol. 90
|
issue 4
821-824
EN
The results of photoluminescence and magneto-luminescence studies of chromium doped ZnSe crystals are presented for blue colour shallow donor-shallow acceptor pair photoluminescence, with a zero phonon line at 2.692 eV. This donor-acceptor pair photoluminescence is observed under photo-excitation with photon energies smaller than the emission energy (anti-Stokes luminescence) and dominates in the photoluminescence spectrum of ZnSe:Cr at the excitation energy about 2.41 eV and for temperature T<20 K. A quantum efficiency of this anti-Stokes luminescence is relatively large. It is of about 10^{-3} at 0 T and increases with increasing magnetic field up to 7 T at temperature T=2 K. We relate the intensity of the anti-Stokes luminescence to a non-equilibrium concentration of photo-excited Cr^{+} ions and propose that the rate of spin-dependent recombination of Cr^{+} ions with free holes (decreases with increasing magnetic field) is responsible for the observed increase in the anti-Stokes luminescence intensity at higher magnetic fields.
19
Content available remote

Photo-ESR Study of the DX to Shallow Donor Conversion in Te Doped Al_{x}Ga_{1-x}As

71%
Surma M., Żytkiewicz Z., Fronc K., Stalinga P., Godlewski M.
Acta Physica Polonica A
|
1993
|
vol. 84
|
issue 4
757-760
EN
Results of detailed electron spin resonance (ESR) study of Te doped Al_{x}Ga_{1-x}As epilayers with x = 0.41, 0.42, and 0.5 Al fractions are presented. It is shown that the ESR signal observed critically depends on cooling steps and that the shallow donor ESR signal can be observed prior to illumination. The first ESR study of AlGaAs layers with removed GaAs substrate are presented. The mechanism of the enhanced photosensitivity of the ESR signal is explained. It is found very paradoxical that the ESR signals decreases upon the illumination even though shallow donor concentration is increased.
20

Genetic diversity among cultivars of spring barley revealed by random amplified polymorphic DNA (RAPD)

71%
Kuczynska A., Milczarski P., Surma M., Masojc P., Adamski T.
Journal of Applied Genetics
|
2001
|
vol. 42
|
issue 1
43-48
EN
RAPD (random amplified polymorphic DNA) polymorphism was studied in 23 malting and non-malting spring barley cultivars included in the official list of Polish cultivated varieties. Twenty-four 10-mer primers were tested in each cultivar, giving altogether 149 amplification products, 45% of which were polymorphic. The number of polymorphic bands revealed by one primer ranged from 1 to 6, with an average of 2.8. Genetic distance for all pairs of compared varieties was estimated and a dendrogram was constructed using unweighted pair group method of arithmetic means. The genetic distance between cultivars ranged from 0.11 for cvs. Apex and Bryl to 0.62 for cvs. Orthega and Madonna. Of the seven malting cultivars only two (Brenda and Stratus) formed one group at D = 0.25. The genetic distance between cvs. Brenda and Scarlett, especially recommended for brewery, was equal to 0.34. The detected polymorphism appeared to be sufficient for assessing genetic distances between cultivars, but on the basis of this polymorphism groups of malting and non-malting cultivars were not clearly distinguished.
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