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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Radosław Łukasz Gwarda, Wojciech Szwerc, Monika Aletańska-Kozak, Anna Klimek-Turek, Andrzej Torbicz, Adam Chomicki, Ryszard Kocjan, Dariusz Matosiuk, and Tadeusz Henryk Dzido

In our previous papers, we have mentioned some specific disruption of peptide zones shape and chromatogram distortion, when using mobile phase containing ion-pairing acids. This problem is investigated here. It concerns not only some specific separation conditions but also various separation systems with silica-based adsorbents and water—alcohol mobile phases. We show that the problem results from significant amount of metallic impurities present in the adsorbents investigated. Our results prove that these impurities strongly affect the activity of free silanol groups and thus the retention of basic or amphoteric compounds and the quality of the results obtained. The standard method of washing adsorbent layer with methanol is not effective against the impurities. Washing chromatographic plates with a solution containing an acid significantly reduces the amount of metallic impurities in the adsorbent, resulting in the reduction/elimination of these adverse effects. However, it also leads to the increase of heterogeneity of acidic groups activity and deterioration of separation system efficiency. Therefore, removing metal ions from the adsorbent may not always be advantageous. Avoiding of use of strong ion-pairing acids is also problematic and not always possible. Thus, the production of high-purity silica of homogenous activity seems to be the best and the most reliable solution of the problem described.

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Gibberellins (GAs) are a class of plant hormones that play important roles in diverse aspects during plant growth and development. A series of GA synthesis and metabolism genes have been reported or proved to have essential functions in different plant species, while a small number of GA 2-oxidase genes have been cloned or reported in wheat. Previous studies have provided some important findings on the process of GA biosynthesis and the enzymes involved in its related pathways. These may facilitate understanding of the complicated process underlying GA synthesis and metabolism in wheat. In this study, GA 2-oxidase genes TaGA2ox1-1, TaGA2ox1-2, TaGA2ox1-3, TaGA2ox1-4, TaGA2ox1-5, and TaGA2ox1-6 were identified and further overexpressed in rice plants to investigate their functions in GA biosynthesis and signaling pathway. Results showed overexpression of GA 2-oxidase genes in rice disrupted the GA metabolic pathways and induced catalytic responses and regulated other GA biosynthesis and signaling pathway genes, which further leading to GA signaling disorders and diversity in phenotypic changes in rice plants.

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Wheat flour was enhanced by linseed fibre, characterised by granulation 500–700 μm. Using seeds from 2015 flax harvest, linseed fibre was gained from two golden and one brown linseed varieties (Amon, Raciol and Recital, respectively). Additions at levels 2.5% and 5.0% affected amylases activity and protein technological quality softly, evaluated by Falling Number and Zeleny sedimentation tests, respectively. Both brown and yellow linseed fibre significantly supported extensograph elasticity of non-fermented dough. Baking potential of composites tested evaluated as extensograph energy significantly decreased about 7–18%, likely owing to dilution of dough gluten skeleton. Pasting behaviour of flour composites reflected a hydrophilic character of non-traditional material – amylograph viscosity was elevated from 590 units to ca 700 units by Amon and Recital fibre, and to ca 930 units by Raciol fibre. Pasting profiles of flour composites, recorded by using of Rapid Visco Analyser, confirmed this finding. Dough fermentation was represented by maturograph test, during which the tested samples were differentiated in part according to the dough resistance. Reflecting small modifications in dough visco-elastic properties, specific volumes of bread buns were similar trough whole sample set. A weak worsening of buns vaulting reflected a partial disruption of dough gluten skeleton. Consumer’s quality of all enhanced bread variants was evaluated in category acceptable, determined as crumb penetration (values higher than 20 mm).

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Abstract

The availability of freshwater is increasingly becoming an international concern because of the increase in population and the diminishing forest area as a source of water, leading to a freshwater crisis. The coastal and swamp areas abound in water, but humans cannot consume it due to the quality. One effort that can be done in overcoming this problem is by treating existing raw water with solar distillation methods. However, the main obstacle faced in this method is the intensity of sunlight that is not stable throughout the day so that the productivity of distilled water is disrupted. Using the appropriate phase change material (PCM) is expected to make the distillation process smoother and increase the production of pure water. In this study, myristic acid was used as PCM in double slope solar distillation system. Through observation, it was obtained that the average water temperature in the basin equaled to 42.5 °C while the melting point of the myristic acid was 58 °C. This shows that the use of myristic acid as an energy storage through phase change process does not occur. Therefore, the use of myristic acid as PCM for increasing the productivity of solar distillation in these experiments is not effective because the melting point of PCM is higher than water temperature in the basin. Therefore, material with a phase change temperature below 42.5 °C is more appropriate to use in these conditions.

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Abstract

The present paper examines the relationship between incantations and belief narratives, two types of oral genres based on human contact with the supernatural. Such contact attests to a dangerous disruption of the boundary between the human and demonic worlds and to the intensive efforts to reinforce it so that participants may return to the space they belong in. For this purpose, various verbal and nonverbal tools are used in belief narratives (gestures, objects, plants, sound or light signals, certain activities – such as walking backwards, placing a cap over the forehead, etc.). In contrast, incantations, an inseparable part of vernacular magical practices, rely solely on verbal communication with impure forces.

This paper will analyse the following aspects of interconnection between these oral genres: 1) the display of a genre within a genre – the presence of incantations in belief narratives, e.g., about dispersing hailstorm clouds; 2) the types of verbal communication with the supernatural in belief narratives (swearing, cursing, command, reproach) and their equivalents in incantations; 3) various motifs of protection from demons (counting the uncountable, using bodily fluids; thorn, fire, metal, broom, etc.). The consideration of shared elements in these genres that preserve the relationship with the mythological narrative include elements of the ceremonial context in which incantations are performed. I argue that some of these elements appear also in belief narratives, where they undergo a transformation.

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Acta Biologica Hungarica
Authors: C. Máthé, G. Vasas, G. Borbély, F. Erdődi, D. Beyer, Andrea Kiss, G. Surányi, S. Gonda, Katalin Jámbrik, and Márta M-Hamvas

This study compares the histological, cytological and biochemical effects of the cyanobacterial toxins microcystin-LR (MCY-LR) and cylindrospermopsin (CYN) in white mustard (Sinapis alba L.) seedlings, with special regard to the developing root system. Cyanotoxins induced different alterations, indicating their different specific biochemical activities. MCY-LR stimulated mitosis of root tip meristematic cells at lower concentrations (1 μg ml−1) and inhibited it at higher concentrations, while CYN had only inhibitory effects. Low CYN concentrations (0.01 μg ml−1) stimulated lateral root formation, whereas low MCY-LR concentrations increased only the number of lateral root primordia. Both inhibited lateral root development at higher concentrations. They induced lignifications, abnormal cell swelling and inhibited xylem differentiation in roots and shoots. MCY-LR and CYN induced the disruption of metaphase and anaphase spindles, causing altered cell divisions. Similar alterations could be related to decreased protein phosphatase (PP1 and PP2A) activities in shoots and roots. However, in vitro phosphatase assay with purified PP1 catalytic subunit proved that CYN in contrast to MCY-LR, decreased phosphatase activities of mustard in a non-specific way. This study intends to contribute to the understanding of the mechanisms of toxic effects of a protein phosphatase (MCY-LR) and a protein synthesis (CYN) inhibitory cyanotoxin in vascular plants.

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Genetic variation for high temperature tolerance exists in wheat cultivars. Identifying key metabolic steps in this regard will help in improving grain yield. Effect of high temperature on activities of sucrose metabolizing enzymes and aminotransferases in relation to transformation of free sugars to starch and protein in developing grains of four wheat cultivars PBW 343, PBW 550, C 306, C 273 was studied by raising the crop under normal (October) and late planting (December) conditions. Significant reduction in chlorophyll content and increase in membrane injury index and lipid peroxidation were observed in all the cultivars. C 306 and C 273 showed higher membrane stability over PBW 343, PBW 550. High temperature accentuated sucrolytic enzymes and aminotransferases while activities of sucrose synthase/phosphate synthase got repressed. Higher build up of sugars and starch in PBW 343, PBW 550 cvs over C 306, C 273 resulted in higher yield in the former but their lower membrane integrity under heat stress leads to yield reductions. Disruption of starch biosynthesis resulted in their favoured utilization in nitrogen metabolism leading to higher amino acid and protein accumulation. Results indicated that sustainability for yield enhancement under stress could be possible by cross-breeding high yielding cvs PBW with increased membrane stability C ones for increasing thermotolerance. Grain filling processes in terms of sugars/starch were strongly correlated to sucrose synthase/phosphate synthase activities while protein to aminotransferases.

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Ultrastructural investigations of the effect of lithium chloride on Botrytis fabae and its host, Vicia faba are described. Five concentrations (1, 3, 5, 7, 9 mM) of lithium chloride are chosen in the study. The results indicate that the chlorophyll content of host leaves is not affected at lower concentration (3 mM), whereas the higher concentration (9 mM) decreased the chlorophyll content. These two concentrations caused a pronounced cellular disorganization of B. fabae that ranged from disruption of the wall to marked cytoplasmic degeneration. Inoculated host leaves with B. fabae led to the appearance of more vacuolated cytoplasm, a disorganized membrane system of chloroplast and an increase in number of plastoglobuli. These observations are similar to those of host cells treated with 9 mM of lithium chloride. Host cells are not affected by the concentration of 3 mM. Ultarstructural studies indicate that the lower concentration of lithium chloride can be used as a safe fungicide to control B. fabae without a harmful effect on the host (V. faba).

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Abstract  

We used artificial planar lipid membranes to investigate, the mode of action of cytolysins of different origin. We studied some pathologically important bacterial toxins (e. g. S. aureus -toxin, C. perfringens -toxin, B. thuringiensis -endotoxin and E. coli -hemolysin). All these toxins are used by the bacteria to damage the cells of the invaded organism. We also studied cytolysins of animal origin which are used to react against the attack of foreign organisms like cytolysins from the nematocysts of sea anemones. These proteins disrupt the permeability barrier of the attacked cell membrane by opening a pore into the lipid matrix. We found that in most cases a receptor is not truly required to render them competent to bind to a cell membrane, they spontaneously insert into preformed pure lipid membranes. Several properties of the resulting pores were compared. They are generally large, water filled, and stay open for long periods. In most cases neutral molecules up to a few kDa molecular weight (like sugars and metabolites) can easily pass through the channel. They are weakly selective, usually being able to discriminate only between anions and cations. The selectivity depends on the presence of fixed charges on the protein since it is modulated by pH and by chemical modification of the protein charged residues.

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We review mechanisms that lead to cyclic evolution with alternating levels of diversity. Such cycles involve directional evolution towards a so-called evolutionary branching point, where selection becomes disruptive and splits the population into two strategies. Coevolution of these strategies eventually leads to the extinction of one of them. The remaining strategy evolves back to the evolutionary branching point, and a new cycle begins. There are a number of different evolutionary mechanisms that can produce this kind of cycles including chance extinction, switching between population dynamical attractors, and coevolution with an ecologically distinct species. We also present an example for branching-extinction cycles where the direction of evolution changes between monomorphic and dimorphic populations solely due to the different levels of diversity. The latter cycles exhibit a novel feature: Even though extinction is deterministic in the sense that it is unavoidable and always occurs at the same trait values, it is random which of the two coexisting strategies goes extinct. As a result, long and short cycles alternate in a random sequence.

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