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Optimum fertilization management is an important technique to alleviate the adverse effects of salinity stress on plants. A pot experiment was conducted to evaluate the ameliorative role of inorganic phosphorus (P) and organic P sources on wheat grown under salt stress in three soil types deficient in available P. Wheat (Triticum aestivum L. cv. Shakha 93) was grown on alluvial, sandy and calcareous soils at salinity levels of 4, 8 and 12 dS/m of saturated paste extract (ECe) and supplied with a constant rate of 30 mg P2O5/kg soil as superphosphate (SP), cattle manure (CM) and a 1:1 mixture of SP and CM. The results revealed that plants grown on the sandy soil were more susceptible to the adverse effects of salinity than those planted on the alluvial one, especially at zero P. Plants grown on the calcareous soil were moderately affected. The varying soil type caused significant differences in the aboveground biomass and the uptake of N, K, P and Zn. It was obvious that P ameliorated wheat growth under salt stress, and this role was greater under moderate and high salinity. The increases in N, P, K and Zn uptake driven by P application were more conspicuous in the sandy and calcareous soils. The results also indicated that the combined application of inorganic and organic P sources surpassed that of either when applied alone on all soil types and salinity levels.

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In order to investigate the effects of salinity on the early seedling growth of chickpea, four chickpea cultivars, Jam, Hashem (kabuli type: large seeded genotypes with light salmon colour), Kaka and Pirooz (desi type: small seeded genotypes with different colours), were grown in pots containing soils with 0.9 (control), 2.6 and 4.9 dSm-1 salinity. The shoot/root ratio of Pirooz was consistently reduced by increasing salinity at all sampling stages. Under saline conditions, the reduction in seedling growth, shoot water content, root and shoot K+ concentration and the increase in root and shoot Na+ concentration were more severe in the kabuli type than in desi type cultivars. Considering path coefficients, increasing seedling K+ concentration and uptake of water from the soil favoured salt-stressed seedling growth. Increasing K+ content alleviated the deleterious effects of root Na+ to a greater extent than that of shoot Na+. On the other hand, a higher percentage of the decrease in seedling growth as the result of Na+ was due to shoot K+ deficiency than to root K+ deficiency.

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The aim of this study was to adapt MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] colorimetric assay (MCA) (Wang et al., 2010) for determination of lactic acid bacteria cell count. Our study is helpful in developing protocols for measuring the viability of other lactic acid bacteria. We determined the cell concentration range which gives linear regression of CFU (colony forming units) and formazan production. In our experiment three authentic lactic acid bacteria strains were investigated: Lactobacillus rhamnosus VT1, L. plantarum 2142, and L. sakei DSM 2001. As data show beside the strain also the growth medium has influence on the MTT reduction activity, this means that for each special case separate calibration curve has to be prepared. Based on MTT reduction we also developed an improved microtiter plate assay which proved to be reliable for a rapid cell count determination. So our methods are only applicable for estimate cell number with fixed parameters, but under given circumstances they are fast and sensitive methods. With the modified methods we can rapidly measure the dehydrogenase enzyme activity of the lactic acid bacteria cells. With the microplate assay we can measure many conditions and strains at the same time.

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In order to investigate the effects of salinity on water use efficiency (WUE) and its components, i.e. transpiration efficiency (TE), uptake efficiency (UE) and harvest index (HI), in chickpea, four chickpea cultivars were grown in pots containing soils with 0.8 (C=control), 2 (S1) and 3.9 (S2) dSm-1 salinity. At S1, the WUE of all cultivars increased, but subsequently decreased with increasing salinity. The relative contribution of TE to the sum of squares of WUE was relatively higher than UE and HI. Therefore, the TE component had a more crucial improving effect on WUE than the other two WUE components. At the S2 level, UE and HI were lower than in the control. Path analysis revealed that the simultaneous selection of non-stressed cultivars for higher TE and HI, and of salt-stressed cultivars for better TE and UE should be practised to improve WUE under non-stressed and high stress conditions, respectively. With respect to ion contents, the screening of salt-subjected cultivars for higher K+ content in the roots might result in an increase in both the total dry matter (TDM) and WUE of chickpea under stress conditions. Additionally, the selection of non-stressed cultivars on the basis of higher shoot Ca2+ concentration might stimulate the TDM and WUE of chickpea under non-stressed conditions.

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Wheat is the second most important crop after rice in India and occupies approximately 28.5 million hectare area. Salinity is one of the major factors reducing plant growth and productivity worldwide, and affects about 7% of world’s total land area. In India about 6.73 million hectare land area is salt affected. The aim of this study was to investigate the morpho- physiological and biochemical response of wheat to temporal salinity (ECiw = 10.0 dSm–1) exposures. Ten wheat genotypes were evaluated in two successive growing seasons (2012–2014), with complete randomized design with three replications under both salinity stress and non-stress conditions. The morpho-physiological and biochemical character measured in this investigation, inhibited under both salt stresses (S1 & S2) conditions but much more significantly inhibited under long-term salinity exposure (S2) than S1 because interrupting the metabolic process of plant, resulting in reduced growth and productivity. According to correlation result, selection of high yield genotypes can be done based on plant height (0.649*), tiller plant–1 (0.808**) and leaf area (0.687*). The multivariate morphophysiological and biochemical parameters should be further used to develop salinity tolerance in wheat breeding improvement programmes.

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Abstract  

True-coincidence summing correction is an essential element in k 0-based NAA1 and becomes important when samples are counted with a high efficiency detector. This may be the case where large detectors are used or where samples are counted in or in the vicinity of the detector in order to achieve low detection limits in conjunction with low-flux reactors. In some laboratories coincidence correction is accomplished by calculating the coincidence correction factors. Since experimental validation of the calculations will reveal only the most significant errors and is a laborious task due to the high number of radionuclides involved, three laboratories decided to compare their calculated coincidence factors. Each laboratory uses a different software package. A comparative performance analysis was made of COINCALC developed at the INW of the University of Gent (implemented in SOLCOI by DSM Research), the software of the IRI, University of Delft, the Netherlands, and the software of the Ecole Polytechnique, Montreal, Canada. The overall approach, data and algorithms were chosen independently by each institute as the software was being developed and, so, the comparison has yielded a number of interesting conclusions. A follow-up investigation of the discrepancies found will probably allow the performance of each program to be improved.

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Abstract  

At the Special Sessionk 0 of the MTAA-8 (Vienna, 1991), and later on at the Intemationalk 0 Users Workshop-Gent (1992), progress was reported with respect to the development and use of computer codes in order to mould thek 0-standardization of neutron activation analysis into an effective working instrument. Among others, this resulted in the software package KAYZERO for PC DOS, which was designed and distributed by DSM Research (Geleen, NL), and which is based on thek 0-methodology, algorithms and nuclear data file developed and created at the INW (Gent, B) and the KFKI (Budapest, H), the traditional k 0-centres. One of the most recent initiatives is a project in the framework of the COPERNICUS programme of the Commission of the European Union. It uses the synergism of a Joint Research Project to give an impulse to the exploitation of KAYZERO-assisted NAA as a manageable and competitive analytical tool in industry and environmental sanitation in Hungary, the Czech Republic and Slovenia. An outline is given of the strategy worked out in this JRP, emphasizing the procedures applied in the three institutes for the calibration of their irradiation facilities and Ge-detectors, quality control and assurance procedures following the implementation of the method, and the identification and tackling of the practical analytical problems which are of relevance to the Central European partner countries.

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European Journal of Microbiology and Immunology
Authors: Trudy M. Wassenaar, Anke Zschüttig, Claudia Beimfohr, Thomas Geske, Christian Auerbach, Helen Cook, Kurt Zimmermann and Florian Gunzer

The probiotic product Symbioflor2 (DSM 17252) is a bacterial concentrate of six different Escherichia coli genotypes, whose complete genome sequences are compared here, between each other as well as to other E. coli genomes. The genome sequences of Symbioflor2 E. coli components contained a number of virulence-associated genes. Their presence seems to be in conflict with a recorded history of safe use, and with the observed low frequency of adverse effects over a period of more than 6 years. The genome sequences were used to identify unique sequences for each component, for which strain-specific hybridization probes were designed. A colonization study was conducted whereby five volunteers were exposed to an exceptionally high single dose. The results showed that the probiotic E. coli could be detected for 3 months or longer in their stools, and this was in particular the case for those components containing higher numbers of virulence-associated genes. Adverse effects from this long-term colonization were absent. Thus, the presence of the identified virulence genes does not result in a pathogenic phenotype in the genetic background of these probiotic E. coli.

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At the Department of Food Technology at Fulda University of Applied Sciences different methods for microencapsulation of Lactobacillus reuteri DSM 20016 were investigated. The aim of these studies was to develop a process to stabilize the probiotic bacteria for storage and to prevent them from the gastric conditions, to ensure that a satisfactory amount of the probiotics could reach their target location, the human intestine. Drying processes like spray drying and freeze drying were tested as well as fluidized bed granulation with optional Wurster coating using different auxiliary materials. As encapsulation material maltodextrine, sweet whey powder or gummi arabicum were used. The coating experiments were performed with an aqueous shellac solution.

In the performed studies the fluidized bed bottom spray granulation with an additional Wurster coating turned out to be an encouraging procedure to keep the probiotics in a stable form resistant against gastric conditions. The survival rate in the simulated gastro-intestinal passage could be increased up to the sevenfold amount of the untreated bacteria.

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Az utóbbi egy-két évtizedben a pszichoterápia kereteiben végzett kutatások, valamint a gyakorlati tapasztalatok azt mutatják, hogy a narratívum és a pszichoterápia szemléletbeli és módszertani összekapcsolása meghatározó alapja lehet a terápiás gondolkodás és gyakorlat megújításának. A narratív szemlélet megújító hatása nem korlátozódik egyetlen terápiás megközelítésre sem, azaz különböző terápiás irányzatok képviselői látnak kiaknázható lehetőségeket ennek a szemléletnek a tudatos beépítésében. A tanulmány áttekinti az élettörténet fejlődésére vonatkozó kutatásokat és a narratív elemzésnek a pszichoterápiában történő alkalmazásait. A narratív tartalomelemzés új eljárásaira támaszkodva a patológiák kategoriális megközelítése helyett mind a diagnosztikában, mind a terápiás folyamat megtervezését és a terápia hatásának vizsgálatát illetően a személyiségfejlődés állapotainak dimenzionális megközelítését javasolja.

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