Monitoring of the fermentation media of citric acid by the trimethylsilyl derivatives of the organic acids formed

In this approach, a derivatization method is described for monitoring of organic acids in fermentation media without any separation step. The aqueous phase of fermentation media was evaporated and heated in a silylation reagent to form trimethylsilyl (TMS) derivatives. The silylated compounds are analyzed by 29Si nuclear magnetic resonance (29Si NMR) and gas chromatography-mass spectrometry (GC-MS). 29Si NMR can qualitatively monitor the components produced in the Krebs cycle. Quantification of these compounds is investigated by using selected ion monitoring mode of mass spectrometry. In this mode, mass to charge (m/z) values of their [M - 15]+ ions, which are 465, 275, 247, 221, 335, 251, and 313 of TMS derivatives of citric, alpha-ketoglutaric, succinic, fumaric, l-malic, oxaloacetic, and palmitic (as an internal standard), acids, respectively, are used. The limit of detection and the linear working range for derivatized citric acid were found to be 0.1 mg L(-1) and 10-3 x 10(4) mg L(-1). The relative standard deviation of the method for five replicates was 2.1%. The average recovery efficiency for citric acid added to culture media was approximately 97.2%. Quantitative results of GC-MS are compared with those obtained by an ultraviolet-visible method.     

Genetic polymorphism of plastid DNA in Tunisian date-palm germplasm (Phoenix dactylifera L.) detected with PCR-RFLP

Fifteen plastid fragments were amplified from a set of Tunisian date-palm accessions by PCR with consensus primers and analysed by RFLP. Polymorphic DNA bands were obtained as reliable molecular markers to estimate genetic distances among the accessions and to examine their phylogenetic relationships. The ctDNA PCR-RFLP method permitted the identification of two haplotypes that differ in the presence or absence of the HinfI restriction site. Phenetic groups composed of cultivars clustered together but does not constitute monophyletic groups. This typology agrees with the haplotypes' organization and provides a common genetic background within the implied varieties.     

Micromechanics of wood subjected to axial tension

Summary The behaviour of a small group of wood fibers of Sitka spruce during tensile loading is investigated. The load-extension curves for both early and late wood fibers consist of three distinct segments. The first segment is almost a straight line, at some stage of loading a yield point is observed. Beyond this point the specimen becomes less stiff and undergoes a large, mainly irreversible deformation. As the load is increased further, the curve exhibits the third segment showed by a significant change in slope. These curves look different from those obtained on thick specimens. In this respect, the behaviour of a thin wood specimen subjected to cyclic type tensile loading along its longitudinal direction is also illustrated. Based on wood microstructure, a model is presented to interpret the evolution of the Young's modulus of a wood fiber during tensile loading. The model considers wood as an assembly of cylindrical fibers pasted together in a longitudinal direction. We have assumed the cell wall to comprise only an S₂ layer made of a composite material consisting of a lignin and hemicellulose matrix reinforced by helical microfibrils along the fiber. Furthermore, it is assumed that the microfibril angle a in the S₂ layer is not uniform along the fiber axis and matrix degradation occurs in the zones where the microfibril angles are bigger. The validity of this assumption is verified by using holographic interferometry to visualize the displacement field of the specimen's surface under tension.The work reported in this paper is supported by a grant from the Swiss National Science Foundation, and its support is gratefully acknowledged     

盐胁迫对扁桃砧木叶片SOD、POD和CAT活性的影响

以温室盆栽的3种扁桃砧木为材料,研究了不同浓度的NaCl、Na2SO4和不同胁迫时间对其叶片活性氧代谢变化的影响.结果表明:NaCl和Na2SO4胁迫下,石头扁桃,桃扁桃和毛桃叶片中POD、CAT活性均随盐浓度的增加而升高,而随着盐胁迫时间的延长其活性有所下降,但都高于对照.SOD活性均随盐浓度的增加先升高后下降,而且后期下降幅度很大.与NaCl胁迫相比,Na2SO4胁迫下这3种砧木叶片中POD、CAT和SOD活性低.从2种盐胁迫下POD、CAT和SOD活性变化规律初步判断这3种砧木的抗盐能力强弱为桃扁桃＞毛桃＞石头扁桃.     

INFLUENCE OF NITROGEN AND SULFUR ON YIELD AND SEED QUALITY OF THREE CANOLA CULTIVARS

In order to investigate the effect of nitrogen (N) and sulfur (S) fertilizers on yield and seed quality of three canola cultivars, a factorial based on randomized complete block experiment was conducted during 2005–2006 in Iran. Treatments included four nitrogen rates (0, 75, 150, and 225 kg N ha^?1 source of urea), four sulfur rates (0, 100, 200, and 300 kg S ha^?1), and three cultivars (‘Pf’, ‘Option-500’, and ‘Hyola-401’). Results indicated cultivar had a significant effect on all studied traits. ‘Option-500’ and ‘Hyola-401’ cultivars had the highest seed yield, protein content, and N:S ratio in seed. The levels of 150 and 220 kg N ha^?1 resulted in the maximum protein content. Increasing N levels resulted in N content and decreased the oil content. The interaction effect between S and N levels showed the highest N content in seed was obtained with 300 kg S ha^?1 and 225 kg N ha^?1.     

Evaluation of growth indices and quantitative traits of safflower under organic farming and conventional agriculture

Application of organic fertilizers in sustainable agriculture systems improves yield sustainability of field crop production. The current research has been formed to investigate the effects of various levels of vermicompost (zero, 3, 6 and 9 t ha^?1) in combination with foliar spraying of potassium humate (0, 1, 2 and 3 mL L^?1) on spring safflower, in Iran during 2012–2013. In addition, inorganic fertilization has been considered as conventional agriculture (CA). In the current experiment, growth indices, seed yield, yield components and flower yield were evaluated. The results showed that the maximum leaf area index, total dry weight and crop growth rate have been determined at 9 t ha^?1 vermicompost and 3 mL L^?1 K-humate while the maximum netto assimilation rate has existed in CA at the emergence of flower buds. Likewise, the results indicated that vermicompost leads to a significant increase in seed yield, flower yield and yield components except 1000 seed weight. Flower yield, head number per plant and seed number per head were affected by K-humate concentrations and increased significantly from 1 to 3 mL L^?1. It should be mentioned that 9 t ha^?1 vermicompost and 3 mL L^?1 K-humate produced the highest seed and flower yield.     

Tyrosine Ameliorates Some of the Clinical,Biochemical and Haematological Effects of Acute Stress Associated with Transportation of Desert Sheep

We studied some clinical, biochemical and haematological variables in Desert (Najdi) sheep acutely stressed in the course of individual road transportation, and the influence thereon of pretreatment with tyrosine. Transportation for 30 min resulted in variable but statistically insignificant increases in heart, pulse and respiratory rates. It also caused significant increases in the plasma concentration of cortisol (from 43.5 to 101.7 mmol/L) and glucose (from 3.1 to 4.5 mmol/L), and a decrease in that of magnesium (from 0.85 to 0.72 mmol/L). The endogenous thiocyanate level was unaffected. The transportation stress also decreased the haematocrit (PCV) and the number of lymphocytes, and increased the concentration of haemoglobin. Pretreatment of sheep with tyrosine at a dose of 100 mg/kg by the intravenous route significantly ameliorated the stress-induced clinical, biochemical and haematological changes. The treatment caused no overt adverse effects.     

Detection of Antibodies Against Peste des Petits Ruminants Virus in Sera of Cattle,Camels, Sheep and Goats in Sudan

Detection of antibodies against peste des petits ruminants virus in sera of cattle, camels, sheep and goats in Sudan.     

Zur Sch?dlingsvertilgung einiger Singvogelarten in einem Schwarzkiefern/Eichen-Mischbestand im Beynamer Wald bei Ankara

Analysis of nestling food in four species of Parus and one species of Ficedula using the 'Halsringmethode' showed a high quota of adults and caterpillars of the important forest pests: Tortrix viridana, Euproctis chrysorrhoea, Diprion pini, and Lymantria dispar. These four major pest species amounted in the nestling food of Parus major to 50%, P. coeruleus to 52.6%, P. ater to 40.9%, and Ficedula hypoleuca to 30.2%.     

The fluorescent antibody and indirect fluorescent antibody assays for diagnosing stunting syndrome of turkeys

The fluorescent antibody (FA) assay was developed for detecting the stunting syndrome agent (SSA) from intestinal tissue. Similarly, the indirect fluorescent antibody (IFA) assay was developed for detecting serum antibodies to SSA. Convalescent antiserum from turkeys orally immunized with SSA was found to be the primary antibody of choice for the FA assay. Intestinal jejunal samples from poults inoculated 3-4 days postinoculation (DPI) was found to be the best antigen source for the IFA assay. SSA was detected from the intestinal tracts of experimentally inoculated birds at 2 DPI with highest level of reactivity at 3 DPI by the FA assay. After 4 DPI the level of SSA infectivity of the intestines waned to low levels. Serum antibody was detected from experimentally inoculated birds as early as 7 DPI with all birds tested seroconverting by 12 DPI. These assays should prove useful for future studies concerning stunting syndrome.