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Experimental results for solar metallurgy, solar powder metallurgy of titanium, solar surface treatment of titanium and titanium welding are briefly reviewed. Most of them were performed at Plataforma Solar de Almeria Spain using solar furnaces SF5 and SF40 in gas/vacuum furnace. Generally, it was observed that the time to achieve required sample temperature is very short when concentrated solar power used. Thanks to use of renewable solar energy these technologies starts to be attractive for industrial production of titanium in Earth solar belt. It can be expected that the obtained results and approaches are similar also in Space. According to the obtained knowledge, the possible solutions/necessary changes for solar furnaces on Moon, Mars and in main asteroids belt are discussed.

The effect of nitrogen (nitrate) deficiency (-N) on the accumulation of cadmium (Cd) and nickel (Ni) in chamomile ( Matricaria chamomilla ) plants was studied. Elimination of N from the culture medium led to decreases in N-based compounds (free amino acids and soluble proteins) and increases in C-based compounds (reducing sugars, soluble phenols, coumarins, phenolic acids, and partially flavonoids and lignin), being considerably affected by the metal presence. Proline, a known stress-protective amino acid, decreased in all -N variants. The activity of phenylalanine ammonia-lyase was stimulated only in -N control plants, whereas the activities of polyphenol oxidase and guaiacol peroxidase were never reduced in -N variants in comparison with respective +N counterparts. Among detected phenolic acids, chlorogenic acid strongly accumulated in all N-deficient variants in the free fraction and caffeic acid in the cell wall-bound fraction. Mineral nutrients were rather affected by a given metal than by N deficiency. Shoot and total root Cd and Ni amounts decreased in -N variants. On the contrary, ammonium-fed plants exposed to N deficiency did not show similar changes in Cd and Ni contents. The present findings are discussed with respect to the role of phenols and mineral nutrition in metal uptake.

Cadmium and nickel uptake by diploid and tetraploid chamomile (Matricaria chamomilla L.) cultivars (Novbona and Lutea, respectively) exposed to 60 microM solutions of individual metals over 7 days was studied. Diploid plants accumulated higher amount of Cd in both shoots and roots compared to tetraploid plants while Ni accumulation was ploidy-independent. Cd presence caused higher accumulation of total soluble phenols and flavonoids and higher phenylalanine ammonia-lyase and guaiacol-peroxidase activities in diploid cultivar in comparison with tetraploid but phenolic acids did not show direct correlation with metal accumulation and even decreased in the leaves of Ni-exposed plants. Lignin content was preferentially elevated in the roots of diploid cultivar. Among 17 free amino acids, their sum increased mainly in the leaves of Cd-exposed plants (owing to increase in serine, alanine and proline). Potassium decrease in both cultivars in response to Cd was ploidy-independent and Ca, Mg and Fe accumulation were almost unaffected. It is concluded that Cd accumulation in chamomile may be mediated by the accumulation of phenols but they have no active role in shoot Ni accumulation. Present findings in the context of our previous studies and limited available literature about ploidy effect on metal accumulation are discussed., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

Chamomile is a widely used medicinal plant and, as observed in our previous studies, also accumulates some metals in its above-ground biomass. We therefore tested selected metabolic responses after treatments with 60 and 120 microM Al for 7 days. Shoot Al content was not elevated in comparison with control (12.3-14.1 microg g(-1) DW) while total root Al increased strongly, reaching 2680 and 4400 microg g(-1) DW in 60 and 120 microM treatments, respectively. "Intra-root" Al represented 83.6 (60 microM treatment) and 75.8% (120 microM treatment) of total root Al. Soluble proteins were not significantly affected. Free amino acids were almost unaffected in shoots while in roots the highest content was found in 60 microM Al. Ascorbate- and guaiacol-peroxidase activities were the highest in 60 microM Al-exposed roots. On the other hand, phenylalanine ammonia-lyase activity, total soluble phenols, flavonoids, a sum of 13 phenolic acids and partially two flavonols (quercetin and kaempferol) increased in the shoots. Present study has shown lower Al toxicity and unaltered shoot Al content seems to be the most positive outcome in comparison with previously tested metals (Cd, Ni and Cu). Our results indicate that phenols in shoots and free amino acids in roots are influenced by Al excess in chamomile plants. Possible mechanisms in the context of available literature are suggested and discussed., (Copyright 2010 Elsevier B.V. All rights reserved.)

Despite intensive research focused on the effects of UV-B, deeper metabolic responses to UV-A and UV-C are still scarce. Besides, especially microalgal species had to develop efficient protective features in comparison with tissue structure of vascular plants. We exposed axenic cultures of Scenedesmus quadricauda (Chlorophyceae) to UV-A (366 nm) and UV-C (254 nm) light over 1 h. Both wavelengths stimulated increase in soluble proteins, superoxide radical and hydrogen peroxide, but had a nonsignificant effect on cell viability. Within 17 detected free amino acids, five (including proline) increased in response to UV-A while only aspartic acid and histidine increased in UV-C treatment. Total soluble phenols and flavonoids were influenced neither by UV-A nor by UV-C while selected flavonols (quercetin and kaempferol) decreased in UV-A and were not detected in UV-C treatment. Benzoic acid derivatives increased preferentially after UV-A illumination (vanillic acid and vanillin) while cinnamic derivatives (caffeic, chlorogenic and p-coumaric acids) decreased in both UV-A and UV-C. It is concluded that UV light stimulated oxidative stress while exposure time was not sufficient to stimulate larger changes in phenolic metabolites. Present findings in the context of available data and with emphasis on phenolics in algae are discussed.

Chamomile (Matricaria chamomilla) is a widely used medicinal plant which also accumulates heavy metals in its above-ground organs. We investigated the effect of the important plant signaling molecule, salicylic acid (SA), on the accumulation of Ni or Cd, by exposing plants over 7 days to 60 microM solutions of individual heavy metals with or without 50 microM SA. Special emphasis was focused on phenolic metabolism-related parameters, not only because of their importance for growth and stress tolerance but also because phenolics are potent antioxidants in human diet. In combined treatments, SA stimulated an increase in soluble proteins of roots and reduced their water content. SA reduced total Cd in the shoot and increased Ni. Total and "intraroot" Ni decreased in Ni + SA treatment, while in the case of Cd, only "intraroot" content decreased in Cd + SA treatment, being correlated with cell wall-bound phenolic acids and lignin. SA was strongly accumulated in roots from the Ni + SA treatment, being correlated with an increase in hydrogen peroxide. In both Cd + SA and Ni + SA treatments, SA enhanced phenylalanine ammonia-lyase activity and accumulation of total soluble phenols, particularly in the roots. Here, we report for the first time that soluble phenols may be involved in Cd shoot-to-root translocation. In the case of Ni, it seems that phenols serve as a root barrier in order to prevent Ni from reaching the above-ground organs. The effects of SA on phenolic metabolism, and the signaling role of ROS in the accumulation of phenols, are discussed.

We examined accumulation of phenolic acids, total soluble phenolics and flavonoids, and activities of phenolic metabolism-related enzymes (shikimate dehydrogenase (SKDH), phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD), polyphenol oxidase (PPO)) in Matricaria chamomilla plants exposed to 3, 60 and 120 microM of nickel (Ni) for 10 days. Ni showed low toxicity as indicated by unaltered content of total soluble phenolics in the leaf rosettes. In the roots, the effects of Ni were more visible, including increased total phenolics and PAL activity, but a decrease in PPO activity was observed. CAD activity was not affected by any of the Ni concentrations. Cinnamic acid derivatives were affected more than benzoic acid derivatives. Accumulation of chlorogenic acid, an important antioxidant compound, was enhanced by Ni treatment (ca. 4-fold in 120 microM Ni). Accumulation of protocatechuic acid, a phenol with high chelating strength, even decreased in the leaf rosettes. These observations are discussed in connection to antioxidative properties of phenolic metabolites and previously tested metals (cadmium and copper).

Two lichen species (Peltigera rufescens and Cladina arbuscula subsp. mitis) and one moss species (Racomitrium lanuginosum) growing on a copper mine heaps (probably 200-300yr old) in the village of Spania dolina (Slovak Republic) were assessed for selected physiological parameters, including composition of assimilation pigments, chlorophyll a fluorescence, soluble proteins and free amino acid content. The lichen C. arbuscula subsp. mitis was collected also at a control locality where total copper concentration in the soil was approximately 3% that of the waste heaps. Concentrations of Al, Co, Cu, Ni, Sb and Zn were highest in thalli of Peltigera, while the moss Racomitrium contained the highest content of Fe and Pb. Thalli of Cladina contained less metals than the cyanolichen Peltigera, and except for Zn metal concentrations in Cladina from the control locality were lower than in thalli of the same species from copper mine heaps. Regardless of the species or locality, the composition of assimilation pigments and chlorophyll a fluorescence showed that the tested lichens and moss were in good physiological condition and adapted to increased copper levels in the soil. There were significantly different amounts of total free amino acids in Peltigera, Cladina and Racomitrium from the Cu-polluted field. However, differences in amount of free amino acids in control, as well as Cu-polluted thalli of Cladina were less pronounced.

Influence of 100 mM NaCl and 50 microM salicylic acid (SA) and their combination on the metabolism of chamomile (Matricaria chamomilla) during 7 days was studied. NaCl reduced growth and selected physiological parameters and SA in combined treatment (NaCl + SA) reversed majority of these symptoms. Application of SA reduced NaCl-induced increase of Na+ in the rosettes, but not in the roots. Accumulation of total amino acids was stimulated in NaCl-treated roots, especially due to exceptional increase of proline (4.4-fold). Among phenolic acids, accumulation of protocatechuic acid was the most enhanced in NaCl-exposed leaf rosettes (ca. 3-fold) while chlorogenic and caffeic acids in the roots (2.4- and 2.8-fold, respectively). Total soluble phenols increased after NaCl and SA treatments, but root lignin content was not affected. Activity of phenylalanine ammonia-lyase and shikimate dehydrogenase increased in response to NaCl, but cinnamyl alcohol dehydrogenase was not affected and polyphenol oxidase decreased. Stress parameters were elevated by NaCl treatment (superoxide radical and malondialdehyde content, activities of catalase, ascorbate- and guaiacol-peroxidase) and substantially prevented by SA, while accumulation of hydrogen peroxide decreased. Overall, SA showed strong beneficial properties against NaCl-induced negative symptoms. Protective effect of SA was the most visible at the level of guaiacol-peroxidase and through amelioration of stress parameters and mineral nutrient contents.

Chamomile (Matricaria chamomilla) in the above-ground organs synthesizes and accumulates (Z)- and (E)-2-beta-D: -glucopyranosyloxy-4-methoxy cinnamic acids (GMCA), the precursors of phytoanticipin herniarin (7-methoxycoumarin). The diurnal rhythmicity of the sum of GMCA (maximum before daybreak) and herniarin (acrophase at 10 h 21 min of circadian time) was observed under artificial lighting conditions LD 12:12. The acrophase is the time point of the maximum of the sinusoidal curve fitted to the experimental data. In continuous light, the circadian rhythms of both compounds were first described with similar acrophases of endogenous rhythms; a significantly different result from that in synchronized conditions. The rhythms' mesor (the mean value of the sinusoidal curve fitted to the experimental data) under free-running conditions was not influenced. Abiotic stress under synchronized conditions decreased the average content of GMCA to half of the original level and eliminated the rhythmicity. In contrast, the rhythm of herniarin continued, though its content significantly increased. Nitrogen deficiency resulted in a significant increase in GMCA content, which did not manifest any rhythmicity while the rhythm of herniarin continued. Circadian control of herniarin could be considered as a component of the plant's specialized defence mechanisms.

Owing to the abundance of phenolic metabolites in plant tissue, their accumulation represents an important tool for stress protection. However, the regulation of phenolic metabolism is still poorly known. The regulatory role of reactive oxygen species (ROS) in the activity of phenylalanine ammonia-lyase (PAL) in nitrogen (N)-deficient chamomile roots treated for 24 h was studied using three ROS scavengers [dithiothreitol (DTT), salicylhydroxamic acid, and sodium benzoate]. Scavengers decreased the level of hydrogen peroxide and/or superoxide (and up-regulated ascorbate/guaiacol peroxidase and glutathione reductase), but, surprisingly, stimulated PAL activity. This up-regulation was correlated with increases in nitric oxide (NO) content, total soluble phenols, selected phenolic acids, and, partially, lignin (being expressed the most in DTT-exposed roots). We therefore tested the hypothesis that NO may be involved in these changes. Application of 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) decreased PAL activity and the accumulation of soluble phenols in all treatments. Exogenous H(2)O(2) and NO also stimulated PAL activity and the accumulation of phenols. We conclude that NO, in addition to hydrogen peroxide, may regulate PAL activity during N deficiency. The anomalous effect of PTIO on NO content and possible mechanism of ROS scavenger-evoked NO increases in light of the current knowledge are also discussed.

Influence of nickel (Ni) excess on selected physiological aspects of Matricaria chamomilla metabolism after 10 days of presence was studied. Biomass, water content, assimilation pigments and lignin contents were not affected by any of the doses tested. High Ni doses elevated root-soluble proteins. The highest Ni concentration stimulated accumulation of soluble phenolics in both the rosettes and roots, and hydrogen peroxide in the roots. Malondialdehyde content was unaltered, but proline content increased more pronouncedly in the rosettes. Histidine was elevated in the roots, suggesting its involvement in Ni retention. Roots contained 3.4, 7.3 and 6.1 times more Ni than leaf rosettes with 3, 60 and 120 microM treatments, indicating that chamomile is a Ni excluder. Leaf rosettes accumulated 174.1 microg Ni g(-1) DW at 120 microM treatment. The results suggest chamomile tolerance to Ni excess and its considerable accumulation in above-ground biomass (ca. 30% of whole plant Ni content).

The influence of salicylic acid (SA) doses of 50 and 250 microM, for a period of up to 7 days, on selected physiological aspects and the phenolic metabolism of Matricaria chamomilla plants was studied. SA exhibited both growth-promoting (50 microM) and growth-inhibiting (250 microM) properties, the latter being correlated with decrease of chlorophylls, water content and soluble proteins. In terms of phenolic metabolism, it seems that the higher SA dose has a toxic effect, based on the sharp increase in phenylalanine ammonia-lyase (PAL) activity (24 h after application), which is followed by an increase in total soluble phenolics, lignin accumulation and the majority of the 11 detected phenolic acids. Guaiacol-peroxidase activity was elevated throughout the experiment in 250 microM SA-treated plants. In turn, some responses can be explained by mechanisms associated with oxidative stress tolerance; these mitigate acute SA stress (which is indicated by an increase in malondialdehyde content). However, PAL activity decreased with prolonged exposure to SA, indicating its inhibition. Accumulation of coumarin-related compounds (umbelliferone and herniarin) was not affected by SA treatments, while (Z)- and (E)-2-beta-D: -glucopyranosyloxy-4-methoxycinnamic acids increased in the 250 microM SA-treated rosettes. Free SA content in the rosettes increased significantly only in the 250 microM SA treatment, with levels tending to decrease towards the end of the experiment and the opposite trend was observed in the roots.

Cadmium (Cd) and copper (Cu) uptake by the plants of Matricaria chamomilla and relation to activities of guaiacol peroxidase (GPX, EC 1.11.1.7), catalase (CAT, EC 1.11.1.6) and glutathione reductase (GR, EC 1.6.4.2) up to 7 days of exposure to 3, 60 and 120 microM Cd or Cu was studied. Cd content in rosettes was ca. 10-fold higher in comparison to Cu while Cu was preferentially accumulated in the roots. In line with this observation, increase of CAT and GPX activity was similar in rosettes of Cd and Cu-treated plants, indicating non-redox active properties of Cd and low Cu accumulation. In the roots, Cu showed strong pro-oxidant effect, as judged from extreme stimulation of CAT and GPX, followed by increase of hydrogen peroxide and malondialdehyde. However, GPX seemed to be more important for alleviation of oxidative stress (ca. 93-250-fold higher activity in 120 microM Cu-treated roots). Cd had substantially lower influences and stimulated GR activity more than Cu. Activities of hydrogen peroxide-scavenging enzymes in relation to its accumulation are also discussed.

Phenylalanine ammonia-lyase (PAL) activity, 11 phenolic acids and lignin accumulation in Matricaria chamomilla roots exposed to low (3 microM) and high (60 and 120 microM) levels of cadmium (Cd) or copper (Cu) for 7 days were investigated. Five derivatives of cinnamic acid (chlorogenic, p-coumaric, caffeic, ferulic and sinapic acids) and six derivatives of benzoic acid (protocatechuic, vanillic, syringic, p-hydroxybenzoic, salicylic acids and protocatechuic aldehyde) were detected. Accumulation of glycoside-bound phenolics (revealed by acid hydrolysis) was enhanced mainly towards the end of the experiment, being more expressive in Cu-treated roots. Interestingly, chlorogenic acid was extremely elevated by the highest Cu dose (21-fold higher than control) suggesting its involvement in antioxidative protection. All compounds, with the exception of chlorogenic acid, were detected in the cell wall bound fraction, but only benzoic acids were found in the ester-bound fraction (revealed by alkaline hydrolysis). Soluble phenolics were present in substantially higher amounts in Cu-treated roots and more Cu was retained there in comparison to Cd. Cu strongly elevated PAL activity (by 5.4- and 12.1-fold in 60 and 120 microM treatment, respectively) and lignin content (by 71 and 148%, respectively) after one day of treatment, indicating formation of a barrier against metal entrance. Cd had slighter effects, supporting its non-redox active properties. Taken together, different forms of phenolic metabolites play an important role in chamomile tolerance to metal excess and participate in active antioxidative protection.

Physiological responses of Matricaria chamomilla plants exposed to cadmium (Cd) and copper (Cu) excess (3, 60, and 120 microM for 7 days) with special emphasis on phenolic metabolism were studied. Cu at 120 microM reduced chamomile growth, especially in the roots where it was more abundant than Cd. Notwithstanding the low leaf Cu amount (37.5 microg g(-1) DW) in comparison with Cd (237.8 microg g(-1) DW) at 120 microM, it caused reduction of biomass accumulation, F(v)/F(m) ratio and soluble proteins. In combination with high accumulation of phenolics, strong reduction of proteins and high GPX activity in the roots, this supports severe redox Cu properties. In terms of leaf phenylalanine ammonia-lyase (PAL) activity, it seems that Cd had a stimulatory effect during the course of the experiment, whereas Cu was found to stimulate it after 7-day exposure. The opposite trend was visible in the roots, where Cd had a stimulatory effect at high doses but Cu mainly at the highest dose. This supports the assumption of different PAL time dynamics under Cd and Cu excess. A dose of 60 and 120 microM Cu led to 2- and 3-times higher root lignin accumulation while the same Cd doses increased it by 33 and 68%, respectively. A Cu dose of 120 microM can be considered as limiting for chamomile growth under conditions of present research, while resistance to high Cd doses was confirmed. However, PAL and phenolics seemed to play an important role in detoxification of Cd- and Cu-induced oxidative stress.

Cadmium was administered to 32 adult ICR mice i.p. in two single doses (0.25 and 0.5 mg CdCl2, per kg of b.w.). After 48 hours concentrations of cadmium in kidneys, liver, spleen, muscle (m. quadriceps femoris), ovaries and testes and the concentration of retinyl palmitate, retinol and beta-carotene in kidney, liver and testes were determined. Significantly higher cadmium concentration was found in liver, kidney and ovary in both experimental groups in comparison with the control group (p<0.001). In muscle, spleen and testis the cadmium level was higher, however not significantly. No significant differences in the concentration of retinyl palmitate, retinol and alpha-carotene in liver were found. Concentration of alpha-carotene in kidney and testis was significantly decreased in both groups administered with cadmium (p<0.001). Concentration of retinyl palmitate was significantly lower in testis in the group with higher cadmium level (p<0.001) and the concentration of retinol significantly decreased in kidney and testis of mice after an administration of 0.5 mg CdCl2/kg b.w.

Acid-base disorders were studied in two groups of dairy cows. According to conventional interpretation in the 1st group of dairy cows (n = 10) the results of the acid-base parameters indicated respiratory alkalosis and in the 2nd group (n = 10) metabolic acidosis. The data of the two groups were examined using principal component analysis. So called "reduced variables"--principal components for each animal were calculated. Each experimental animal was projected in the coordinates of 3 principal components K1, K2 and K3. The components K1, K2 and K3 comprised a 90% data variability. The importance of variables for a dividing of groups (1 and 2) was quantified. The most important were pCO2, (HCO3)' and BE. It was proved according to mathematico-empiric equations that dairy cows of 1st group suffered from acute respiratory alkalosis. In the 2nd group of dairy cows the combined acid-base disorder was confirmed using the equations for metabolic acidosis and chronic respiratory acidosis. The use of PCA method and empiric equations for acid-base imbalances shows the possibilities for gaining new knowledge how to make the diagnostic process more exact.

The aim of the study was to observe the effect of longer fasting of dairy cows during lactation on the insulin and thyroxine levels in blood serum. The test was performed at the Research Institute of Animal Production, Nitra. The blood samples for determination of the hormone levels were collected in the morning from the vena jugularis of four fasted 4-5-year-old dairy cows of the Black Pied breed during lactation with an average daily performance of 16.91. The blood was collected on the first, fifth, sixth, seventh, eight and ninth day (fasting) and then on the fifteenth and twenty first day of the test (feeding). The insulin level in the blood serum of fasted dairy cows was more or less balanced till the seventh day of fasting, and ranged from 4.33 to 4.91 microU.ml-1. On the last two days of fasting, the insulin level increased up to 7.11 microU.ml-1 on the 9th day of fasting. The insulin level was significantly higher during feeding than during starvation. The thyroxine level was statistically significantly lower in fasted dairy cows. Increasing insulin level at the last two collections of the fasting period was probably closely connected with the shifting of the endocrine balance from dominant position of insulin to the dominance of the growth hormone and glucocorticoids. A comparatively high effect on the increase of the insulin level was exerted during that time also by the increasing amounts of non-esterifed fatty acids. Starvation significantly reduced the levels of the studied hormones in dairy cows during lactation.

Isolating of F. tularensis from gamasid mites H. nidi parasitizing on the bank vole (Cl. glareolus) and L. hilaris on the common vole (M. arvalis) are reported. The epidemiological significance of this finding is discussed.

In blood serum of dairy cows of the Slovak Pied breed with high and low performance, the levels of total protein, urea, amino nitrogen, non-protein nitrogen and uric acid were studied over the period of four to six weeks after calving. Total protein was determined by the Bio-La-test, amino nitrogen by means of ninhydrin, non-protein nitrogen by Berthelot agent and uric acid by Benedict agent. In comparison with dairy cows with low performance, the dairy cows with high performance had a statistically significantly higher level of total protein, urea, amino nitrogen and non-protein nitrogen. The differences in uric acid content were statistically insignificant.