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Resonant photoemission spectroscopy (RPES), which is a useful tool for extracting photoemission response of the localized Rare Earth (RE) impurity levels from the host electronic band structure, was used to study ZnO:Yb films. The resonant enhancement of the photoemission signal at binding energy around 7.5 and 11.7 eV was observed when photon energy was tuned to the Yb 4d-4f absorption threshold (182 eV). It was found that the 4f and the valence band (VB) maximum binding energies do not depend on the Yb dose, suggesting that the measurement of only one concentration is sufficient to determine the binding energies of the Yb 4f in the examined system. Subsequent annealing did not change the arrangements of implanted ytterbium atoms in host matrix: the majority of them remain in 3 + state having pseudo-octahedral local arrangement similar to Yb2O3.

The structural, electronic, and magnetic properties of low-energy rhenium implanted c-Si are examined for the first time. The damage created by rhenium ions and the following partial reconstruction of the silicon host matrix after rapid thermal annealing (RTA) are investigated as a function of the fluence. Rutherford backscattering spectrometry (RBS) results reveal that the implanted ions are located in the near-surface region with the distribution maximum at about 23 nm below the surface. The analysis of rhenium-depth distribution using the McChasy code shows that the implanted Re-ions are located in the interstitial lattice positions. The RTA leads to a partial recovery of the silicon crystal structure. According to the RBS results, the formed inclusions are not coherent with the silicon host matrix causing an increase of the lattice distortion. Analysis of channeled RBS/c spectra carried out by the McChasy code revealed different levels of bent channels in damaged regions suggesting bimodal distribution of inclusions in the silicon. Studies of high-resolution X-ray photoelectron spectroscopy (XPS) conducted after the RTA showed the shift of Re 4f7/2 binding energy (BE) by +0.68 and + 0.85 eV with respect to metallic rhenium for the samples with lower/higher fluencies, respectively. Complex XPS, density functional theory (DFT) simulations, and transmission electron microscopy (TEM) data analysis allowed us to conclude that the near-surface layer of the sample (∼10 nm) consists of nanoinclusions with cubic and/or hexagonal ReSi. In the middle area of the samples, much larger nanoinclusions (>10/20 nm for higher/lower fluencies, respectively) containing pure metallic rhenium inside are formed. The RTA increases the magnetic moment of the sample with the lower dose nearly 20-fold, whereas in the sample with the higher dose a 3-fold increment is observed only. The magnetic response of the examined systems after the RTA indicates a presence of magnetic interactions between the nanoinclusions resulting in the system exhibiting super-spin glass or super-ferromagnetism.

Carbon-based materials are the promising candidates for future applications in novel electronics. Carbon nanotube transistors and logic gates, conducting carbon-based polymers have been already demonstrated. In addition some forms of pure carbon should reveal magnetic properties, which in principle might be use in carbon-based spintronics. There are some theoretical predictions about carbon nano-stripes, schwarzite structures, H-doped graphite, in which electron spins on π-orbitals or broken sp 3 -bonds have (in some cases) ferromagnetic alignment. The experiments seeking for ferromagnetism were performed but many of them have failed due to the presence of ferromagnetic impurities (mostly iron). Nevertheless some of the experiments demonstrated ferromagnetism in pure carbon, particularly in carbon nano-foam [1] and proton-irradiated highly oriented pyrolitic graphite (HOPG) [2]. In 2003 Esquinazi used a MeV proton beam and discovered that it trigged ferromagnetism of the HOPG sample. After irradiation the hysteresis loop was observed over the irradiated area using Magnetic Force Microscopy and SQUID measurements. Such magnetic system seems to be very interesting for both: basic science and possible application points of view. However, hardly any other experimental group has confirmed such experimental observation. This situation is embarrassing, because it is not clear if nobody tried to verify the discoveries of Esquinazi et al. or nobody has succeeded in this verification. And since the lack of the phenomenon is difficult to be publish in any paper (vide the rumor of “cold fusion” in 90-ties) there are no information about the efforts of other groups. We have tried to repeat this discovery of the gropup of Esquinazi et al. We have used He + and H + beams focused on graphite sample. The amount of charge deposited in the sample was comparable to the amount of charge used by Esquinazi. Magnetic measurements were performed in SQUID magnetometer. The magnetization of the samples before and after irradiation was compared. Unfortunately we did not observe any ferromagnetic enhancement of magnetization of our irradiated samples. Even if experiment was not the same as Esqinazi’s one, we can exclude some of the mechanisms of ferromagnetism proposed by Esquinazi.

Transport studies of as-grown and proton-irradiated n-InN have been performed aiming at verification of the nature of localized donor states resonant with the InN conduction band. These resonant donor states (RDS) show a clear contribution to the electrical conduction in low electron concentration InN epitaxial layers. We used proton irradiation to increase the number of incorporated native point defects of donor character in InN layers. Then, the performed studies of pressure dependence of the Hall electron concentration clearly show no increase in the number of RDS in samples exposed to irradiation in spite of the increase in the conducting electron concentration.

The objective of the present work was to study all physiological relationships among selenium status (SeS), sex hormones secretion (SH), and thyroid metabolism (ThM) in healthy adolescent girls, at one time. Forty-four girls aged 13.4-16.6 years (mean age, 14.5 +/- 0.5 years) entered the statistical model. Parameters reflecting SeS: plasma selenium concentration (Se) and plasma glutathione peroxidase activity (GPX3); SH: serum estradiol (E2) and progesterone (P4); age of menarche (AoM); and ThM: thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), antithyroid peroxidase antibodies (anti-TPO) in serum, and thyroid volume (ThV), were determined, and the interactions between them were evaluated by means of the partial least squares method (PLS). PLS method was, for the first time, successfully applied to the problem of selenium and hormone interactions and revealed that selenium status and female reproductive system are interrelated and affect thyroid physiology in adolescent girls in the luteal phase. The strongest associations were revealed for the pairs of parameters, Se and fT4/fT3, Se and P4, the modest ones for the pairs, Se and ThV, P4 and fT4/fT3, Se and AoM, and P4 and AoM. There was no correlation between E2, GPX3, and TSH, and any other considered parameter. Se and P4 had the greatest influence on ThM parameters.

The occurrence of oxidative stress and oxidative damage in the halophyte Mesembryanthemum crystallinum during C 3 /crassulacean acid metabolism (CAM) transition evoked by salinity and high irradiance was investigated. The hypothesis tested was that CAM induction will effectively protect M. crystallinum against oxidative damage even under additionally applied oxidative stress via ozone (150 p.p.b.) exposure. Salinity (0.4 M NaCl), high irradiance and ozone induced the cytosolic CuZn-superoxide dismu- tase (SOD; EC 1.15.1.1) transcript abundance and activity indicating oxidative stress. However, ozone did not induce CAM. Contrary to the hypothesis, that ethylene may be involved in CAM induction, gassing with ethylene (200 p.p.b.) did not lead to CAM, but revealed that in M. crystallinum ethylene biosynthesis is induced by autostim- ulation. A putative fragment of the hitherto unknown nu- cleotide sequence of 1-aminocyclopropane-1-carboxylate oxidase (ACC; EC 4.4.1.14) was isolated and used as a specific probe against the ACC oxidase transcript to moni- tor oxidative damage. Ozone exposure increased the ACC oxidase expression only in plants with C 3 -photosynthesis which also showed severe necrosis and reduced photosyn- thetic activity, whereas plants in CAM mode (salt induced) remained unaffected. Natural stressors such as salinity and high irradiance induce CAM and up-regulate the ARS component CuZn-SOD very effectively to protect M. crys- tallinum from oxidative damage even when additional oxi- dative stress such as ozone is present.

Possible interactions between selenium and iodine metabolism were investigated in 7- to 16-year-old children with goiter (n = 136) living in southeastern Poland in iodine-deficient areas influenced by a sulfur industry. The Se-iodine interactions in these children were compared to the interactions in children from outside of that region (n = 38). Blood selenium (BSe) concentration and plasma glutathione peroxidase activity were much lower in the study group (64.1 +/- 15.7 microg/L; 111.0 +/- 27.6 U/L) than in the control group (85.3 +/- 19.6 microg/L; 182.4 +/- 35.6 U/L). Almost all of the data [plasma thyroid-stimulating hormone (TSH) concentration, plasma free thyroxine (fT(4)) concentration] fell within the reference limits. There was no statistically significant difference between the control and the study groups with respect to fT(4) and TSH. However, statistically significant differences of fT(4) and TSH in the study group were revealed between females belonging to the lower (n = 21; fT(4), 16.1 +/- 3.3 pmol/L; TSH, 1.83 +/- 1.05 mU/L) and upper Se quartiles (n = 24; fT(4), 14.5 +/- 2.2 pmol/L; TSH, 1. 26 +/- 0.90 mU/L), p < 0.05. Neither group differed in iodine in urine concentration, age, and body mass index. The difference in fT(4) concentrations can be attributed to an Se deficiency. The relationship exists only for females, which suggests a sex-linked hormonal response to concomitant Se and iodine deficiencies. Images Figure 1 Figure 2

There are two H+-pumping enzymes at the tonoplast membrane of plant vacuoles, the V-ATPase and the V-PPase. One attempt to explain the enigma of “two H+ pumps, one membrane” was the suggestion that the V-PPase has special functions in young developing and growing tissues in utilization of pyrophosphate produced in particularly active metabolism and in pumping of K+ for vacuolization. This should lead to reciprocal expression of both enzymes with time during development. Here we used stimulation of Kalanchoe blossfeldiana Poellnitz cv. Tom Thumb plants by short-day treatments to induce crassulacean acid metabolism and flowering and of Ricinus communis L. stem tissue by infection with Agrobacterium tumefaciens strain C58 to induce vigorous growth of tumours, and we compared these stimulated tissues with leaves of non-stimulated long-day controls and non-infected stem tissue, respectively. Activities and protein levels of both enzymes increased (K. blossfeldiana) or remained high (R. communis) in the stimulated tissues and decreased in the non-stimulated tissues with time. Time-dependent patterns of the two enzymes were concordant in all of the four cases and not inverse, i.e. two plants with two different conditions each, leading to very different developmental situations.

Microsomal membranes of Chlamydomonas reinhardtii possess PPase and V-ATPase activities. By immunogold labelling we have shown that H+-pyrophosphatase (PPase) is localized to membranes of lytic and contractile vacuoles of Chlamydomonas, in which the density of antigen in the latter is much higher. In addition, PPase is conspicuously present in trans cisternae and transpole elements of the Colgi apparatus. Such a distribution for PPase has hitherto not been reported. A positive in situ identification for PPase at the plasma membrane, including the flagellar membrane, was also made, and has also been confirmed by Western blotting and activity measurements on isolated plasma membranes. V-ATPase antisera which cross react with polypeptides of this transport complex from maize roots failed to recognize anything in Western blots of Chlamydomonas microsomal membranes. Thus immunogold labelling for V-ATPase was not possible with Chlamydomonas. On the other hand, surfaces of contractile vacuole membranes as revealed by deepetching were covered by conspicuous 9 − 11.5 nm diameter smooth particles which had a central hole. These were very similar to those previously identified by Heuser et al., (1993) as the V,-head of V-ATPase in Dictyostelium contractile vacuoles. Another type of membrane image, designated “intermediate-sized vesicle”, was found associated with the contractile vacuole. It was characterized by densely-packed 6 − 7.5nm diameter polygonal particles, which upon rotation analysis showed both 5- and 6-fold symmetries, also with a central hole. These particles are interpreted as representing either PPase complexes or the V0 body of the V-ATPase in etched fractured membrane surfaces. We have incorporated these findings into a model of contractile vacuole function.

BSA, bovine serum albumin CAM, Crassulacean acid metabolism DTT, dithiothreitol EDTA, ethylenediaminetetraacetic acid FPLCfast protein liquid chromatography HEPES, N-(2-hydroxyethyl)piperazine-Ń-(ethanesulphonic acid) ME, β-mercaptoethanol NBT, nitro blue tetrazolium PAGE, polyacrylamide gel electrophoresis SDS, sodium dodecyl sulphate SDS-PAGE, sodium dodecyl sulphate polyacrylamide gel electrophoresis Rubisco, ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39) SOD, superoxide dismutase (EC 1.15.1.1) TEMED, N,N,Ń,Ń-tetramethylethylenediamine Tris, Tris (hydroxymethyl) aminomethane Tricine, N-Tris(hydroxymethyl)methylglycine Treatment of Mesembryanthemum crystallinum for several days with 0·4 kmol m–3 NaCl in the root medium, in parallel to an increase of the cell sap osmolarity enhances activity of important antioxidative enzymes, such as superoxide dismutases (SODs). M. crystallinum is equipped with three SOD isoforms. These isoforms were identified as Mn-, Fe-, and Cu/Zn-SODs, respectively. Mn-SOD was found in the mitochondrial fraction, Fe-SOD in the chloroplast fraction, and Cu/Zn-SOD is probably localized in the cytosol. The Fe-SOD found in M. crystallinum is the first iron-containing SOD enzyme to be characterized in the plant family Aizoaceae. Salt treatment increases the activity of this isoform earlier than the other SODs. Molecular masses of SOD isoforms were determined as 82, 48 and 34 kDa for Mn-, Fe-, Cu/Zn-SODs, respectively. Native Mn-SOD seems to be a tetramer, while Fe-SOD and Cu/Zn-SOD are dimers. All SOD isoforms show high thermal stability. Mn-SOD is active even after short heating at 90 °C and Fe-SOD at 70 °C. Moreover, high concentrations of β-mercaptoethanol used as a reducing agent did not destroy the function of all isoforms. With the salinity treatment in M. crystallinum, Crassulacean acid metabolism (CAM) is induced. Build-up of large stationary O2 concentrations in the leaf air spaces is associated with the photosynthetic CO2 reduction behind closed stomata in phase III of CAM. This illustrates why M. crystallinum may require higher antioxidative activities under NaCl stress and also explains earlier findings that CAM plants are more resistant than C3 plants to environmental stress as imposed by, for example, SO2 and O3.

The effects of solubilization with Triton X-100 or Brij 58 on the polypeptide composition and the substrate affinity of the tonoplast H+-ATPase of plants of Mesembryanthemum crystallinum performing C3 photosynthesis or crassulacean acid metabolism (CAM) have been compared. Although all known subunits of the tonoplast H+-ATPase were present in the fraction of solubilized proteins after treatment with Brij 58 or Triton X-100, with Triton X-100 the apparent KM value for ATP hydrolysis was increased by a factor of 1.8 and 1.5 in preparations from C3 and CAM plants, respectively, even at low concentrations in contrast to treatment with Brij 58. This is explained by structural changes of the tonoplast H+-ATPase due to the Triton X-100 treatment. After solubilization with Brij 58 the tonoplast H+-ATPase was partially purified by Superose-6 size-exclusion FPLC. When Brij 58 was present, addition of lipids to the chromatography buffer was not necessary to conserve enzyme activity in contrast to previously described purification methods using Triton X-100. The substrate affinity of the partial purified H+-ATPase was similar to the substrate affinity obtained for ATP-hydrolysis of native tonoplast vesicles, indicating that the enzyme structure during partial purification was conserved by using Brij 58. The results underline that the lipid environment of the tonoplast H+-ATPase is important for enzyme structure and function.

Summary IA detergent removal technique was used to reconstitute solubilized tonoplast proteins of mesophyll cells of the CAM plant Kalanchoe daigremontiana into phosphatidylcholine liposomes. The proteoliposomes were able to hydrolyse ATP and to pump protons across the vesicle membrane. Both activities were inhibited by nitrate, an inhibitor of V-type ATPases. Freeze-fracture micrographs confirmed the incorporation of membrane proteins into liposomes. Increase of specific ATP-hydrolysis activity compared to solubilized tonoplast proteins and SDS-PAGE analysis of reconstituted proteins in comparison with the polypeptide pattern of the purified tonoplast H+-ATPase from the same plant source indicated a highly selective reconstitution of the tonoplast H+-ATPase.

Recently published biochemical data suggest the significant role of selenium compounds as the adjuvants combined with L: -thyroxine therapy, which can reduce antithyroid peroxidase antibodies' (TPOAb) levels in patients with Hashimoto disease. The study was undertaken to document in a more detailed way the changes in parameters expressing the thyroid and ovarian function brought about by selenium supplementation (50-100 microg/day) in a woman undergoing autoimmune thyroiditis (AIT) therapy. This prospective observational case study lasted for 14 months plus additional 5 months as a follow-up period. Parameters reflecting selenium status, thyroid metabolism, and sex hormones secretion were determined at the onset and end of the study period, as well as in some of its middle points. During the supplementation trial, serum selenium (Se) increased by 45% and plasma glutathione peroxidase (GPX3) by 21%. TPOAb decreased by 76%. All other parameters also fluctuated during the supplementation period, but all results were always within normal physiological ranges. After withdrawal of the supplementation, the sharp fall of Se and GPX3 promptly occurred, and this phenomenon was accompanied with a marked increase in TPOAb. This report stresses the importance of selenium supplementation in AIT treatment. However, the efficiency and durability of the effect of Se supplementation on the TPOAb titer remain an open question. The clarification of mechanism(s) underlying Se interaction with autoimmune processes should throw new light on this issue.

The aim of the study was to identify those parameters characterising selenium status and sex hormones secretion, which are responsible for the changes in indicators of thyroid function, and to reveal the correlation structure of parameters expressing selenium status, sex hormones secretion and thyroid function, if any exist. The general approach in this work was essentially the same as in our previous report (cf. [Zagrodzki P, Ratajczak R, Wietecha-Posluszny R. The interaction between selenium status, sex hormones, and thyroid metabolism in adolescent girls during the luteal phase of their menstrual cycle. Biol Trace Elem Res 2007; 120: 51-60]), but the study group and parameters' spectrum were different. Thirty-six women aged 23.5+/-0.6 years were investigated. The parameters of interest were: plasma selenium concentration (Se) and plasma glutathione peroxidase activity (GPX3) (indicators of selenium status); serum estradiol (E2), progesterone (P4), follicle-stimulating hormone (FSH), luteotropic hormone (LH), and age of menarche (indicators of sex hormones secretion); thyroid-stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), anti-thyroid peroxidase antibodies in serum (anti-TPO), and thyroid volume (indicators of thyroid function). Our findings show that Se, GPX3, P4, LH, FSH, TSH and fT4 were interrelated. The pairs of parameters: GPX3 and P4; LH and FSH exhibited the strongest associations. The thyroid function parameters were mainly influenced by GPX3 and P4. Partial least-squares method corroborated our hypothesis about the existence of complex interactions among selenium status, sex hormones secretion, and thyroid function in healthy young women in the luteal phase.

Modification of materials is a wide area in materials science, especially surface modification. To investigate the results of the modification process, treated and nontreated samples were compared. Intense plasma pulses of argon or nitrogen were used to irradiate the carbon steels. In all samples, the near-surface layer was melted. Results of scanning electron microscopy investigations of the surface morphology and cross-sections, as well as the results of tribological tests, are presented. The obtained results allowed us to draw conclusions about changes in material properties and to propose subsequent studies using other investigation techniques.

The present study deals with the phenotypic adaptation of tonoplast fluidity in the CAM plant Kalanchoë daigremontiana to changes in growth temperature. Tonoplast fluidity was characterized by measuring fluorescence depolarization in membranes labeled with fluorescent fatty acid analogues and by following formation of eximeres in membranes labeled by eximere-forming fluorophores. With both techniques it was found that exposure of the plants to higher growth temperature compared with the control decreased the fluidity of the tonoplast while exposure to lower growth temperature caused the opposite. Three hours of high temperature treatment (raised from 25 degreesC to 35 degreesC; "heat shock") were sufficient to decrease the tonoplast fluidity to roughly the same extent as growth under high temperature for 30 days. The phenotypic response of tonoplast fluidity to changes in growth temperature was found only in the complete membrane, not however in the lipid matrix deprived of the membrane proteins. Heat treatments of the plants decreased the lipid/protein ratio while exposure to low temperature (for 30 days) increased it. Heat treatments led to a decrease in the percentage of linolenic acid (C18:3) and linoleic acid (C18:2), heat shock and low temperature treatments induced an increase in the percentage of linoleic acid (C18:3), with concomitant decrease in the percentage of linoleic acid (C18:2). However, in the case of heat shock, increase in linolenic acid concerned mainly monogalactosyldiacylglycerol, while with low temperature treatment linoleic acid increased in phosphatidylcholine. Both treatment of the plants with high and low temperature led to a slight decrease in the contribution of phosphatidylcholine and phosphoethanolamine to the total phospholipid content of the tonoplast. High-temperature treatment of the plants not only decreased the phospholipid/protein ratio in the tonoplast, but also led to the occurrence of a 35 kDa polypeptide in the tonoplast which cross-reacted with an antiserum against the tonoplast H+-ATPase holoenzyme. The important role of membrane proteins in bringing about the phenotypic rigidization of the tonoplast was mimicked by reconstitution experiments showing that incorporation of the proteins isolated from the tonoplast into phosphatidylcholine vesicles decreased the fluidity of this membrane system. As to be expected from the analyses in the natural membrane, the degree of this effect depended on the phospholipid/protein ratio.

In neonates the thyroid gland is very sensitive to iodine deficit. This hypersensitivity is due to a less efficient mechanism of adaptation to iodine deficiency (1). The main purpose of the present study was to evaluate the thyroid function in newborns for whom four different thyroid Iodine Deficiency Disorders (IDD) were diagnosed: hypothyroxinemia, transient hypothyroidism, hyperthyrotropinemia without goitre, and hyperthyrotropinemia with goitre. The study was carried out shortly after the iodine prophylaxis (salt iodisation) in Poland had been resumed after nearly 10 years of break. So, it was interesting to compare the evolution of particular disorders in subsequent years and the evolution of correlations between parameters used to diagnose cases. Some relevant insights were done by help of factor analysis, which aimed to explain the observed relations among parameters and to find basic casual influences on them. As a research instrument, factor analysis and other pattern recognition methods have been used in numerous studies dedicated to clinical practice and epidemiology (2–4).

The antenna of photosystem (PS) I in higher plants, green algae, and cyanobacteria contains various chlorophyll (Chl) pigment proteins each with characteristic absorbance and corresponding fluorescence spectra. A pigment called C695 has been held responsible for the low and room temperature fluorescence emission F720 while a pigment C705 is attributed to the low temperature emission band F730. The bulk of the PS I Chl a antenna absorbs at ∼ 678 nm and generally emits with a maximum around 684 nm and sometimes up to 695 nm at room temperature (F685).

Sub-Carpathian region in Poland is known as an Iodine deficient area. 5 groups of babies with thyroid gland disfunction were selected on HT screening: Congenital hypothyroidisn was detected in 15 cases (1:5011) the transient hypothyroidism in three (1:25551) and 88 patients were diagnosed as having IDD (Iodine Deficiency Disorders)including 42with transient hyperthyrotropinemia, 46 with goiter with or without concomittant hyperthyrotropinemia. The high incidence of IDD in this area seems to be connected wth the insufficient Iodine suplementation in the years 1981-87. The Iodine urine excretion confirmed the moderate environmental Iodine deficiency in the studied area. Conclusions: 1/ The prevalence of congenital hypothyroidism in Krakow district is 1:5011. 2/Krakow belongs to the class II Iodine deficient areas. 3/The incidence of the IDD in this area is 1:824. 4/The correction by Iodine salt suplementation seems urgent.