abstract nitrogen is a key nutrient in plant growth and it is necessary for amino acid synthesis. sulfur has very important role in the biosynthesis of the alliums flavor and pungency precursors and potassium improve crop yield and quality. in order to study the effect of ammonium nitrate and potassium sulfate on concentration some of the mineral elements in onion (allium cepa l. azar shahr cv....

the design and application of a fuzzy logic based controller to a leakage current relay waspresented in this paper. a novel approach based on fuzzy logic to form the tripping action of leakagecurrent relay was investigated. in addition to the theoretical aspect of fuzzy logic, detection of a leakagecurrent, measurement of the leakage current, determination of its duration, trip opening of fault...

A method similar to the sucrose-gap technique introduced be Stäpfli is described for measuring membrane potential and current in singly lobster giant axons (diameter about 100 micra). The isotonic sucrose solution used to perfuse the gaps raises the external leakage resistance so that the recorded potential is only about 5 per cent less than the actual membrane potential. However, the resting p...

OBJECTIVES The mode of action of dysgalacticin, a large (21.5 kDa), heat-labile bacteriocin that is active against the human pathogen Streptococcus pyogenes, was investigated. METHODS We used recombinant dysgalacticin to determine its mode of action against S. pyogenes. Antimicrobial activity of dysgalacticin was determined by MIC assays and viability counts. The extracellular pH of glucose-e...

The present study was designed to evaluate the effects of flavonoids luteolin (L) and quercetin + luteolin (Q + L) in combination with commonly used antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates and S. aureus (ATCC 43300). Minimum inhibitory concentrations (MICs) of L and Q + L, as well as the MICs of flavonoids in combination with antibiotics...

Lactobacillus helveticus strain LP27 produced a bacteriocin, lactocin 27, in dialyzable and nondialyzable forms. No evidence was obtained to indicate that lactocin 27 was under the control of extrachromosomal plasmids. Lactocin 27 had a bacteriostatic effect on the indicator, Lactobacillus helveticus strain LS18. It inhibited primarily protein synthesis without affecting deoxyribonucleic acid a...

The permeability of K channels to various cations is studied in myelinated nerve. Ionic currents under voltage clamp are measured in Ringer solution containing tetrodotoxin and a high concentration of the test ion. Reversal potentials for current in K channels are determined and used with the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The ratios PTI:PK:PRb:PNH4 are 2.3:...

The addition of lead to normal human blood was previously found to cause a decrease in erythrocyte osmotic fragility in vitro. The mechanism of the decreased osmotic fragility caused by lead has not been completely clarified, but the following hypothesis has been proposed. Lead causes a leakage of water from erythrocytes, thus more water can enter the cell before haemolysis occurs. There has be...

An outdoor pot experiment was carried out in sand culture to investigate the response of spinach (Spinacia oleracea ) cv. “Matador” grown at high salinity to supplementary phosphorus and potassium. Plants were tested during a period from germination to vegetative growth stage. Treatments initiated for seedling and more matured vegetative growth stages were (1) complete nutrient solution alone (...