Boron is an essential micronutrient for plants, and it is beneficial for animals. However, at high concentrations boron is toxic to cells although the mechanism of this toxicity is not known. Atr1 has recently been identified as a boron efflux pump whose expression is upregulated in response to boron treatment. Here, we found that the expression of ATR1 is associated with expression of genes in...

Borosilicate zeolites have recently been studied in many aspects because they are useful in substitution of framework metal ions (to Al or Ga) and in catalyzing chemical reactions that use relatively weak acid strength. Boron shows a great extent of flexibility in coordination conversion between trigonal boron, B[3], and tetrahedral boron, B[4]. Such conversion takes place in the framework of b...

________________________________________________________________________________ Abstract In this study dietary boron at different doses (0, 25, 50, 100 and 200 mg/kg feed) was supplemented to layers from 4 to 64 weeks of age. There was no significant difference between treatments with respect of mortality, egg production, egg weight, egg mass and cracked eggs. Significant increases were observ...

PURPOSE There is a clear need for a technique that provides subcellular locations of fluorine and boron atoms from fluorinated neutron capture agents because positron emission tomography is being tested as a tool for providing tumor boron concentrations in boron neutron capture therapy. EXPERIMENTAL DESIGN Ion microscopy was used in combination with confocal laser scanning microscopy to inves...

background and objectives: drought stress is one of the most important environmental factors reducing growth and yield of crops, especially in arid and semiarid regions of the world. during drought stress, nutrient uptake diminishes due to rising of solute concentrations and so increasing of osmotic potential in the root zone. with increasing soil ph, micronutrient uptake decreases more than ot...

The role of di-boron diffusion in evolution of B diffusion profiles has been investigated. We find that boron pair (Bs – Bi) diffusion can become as important as boron-interstitial pair (Bs – Sii) diffusion when both boron concentration and annealing temperature are very high, leading to concentration-dependent B diffusion. Our simulated B diffusion profiles with dramatic shouldering are in exc...

Boron exhibits anomalous diffusion during the initial phases of ion implant annealing. Boron transient enhanced diffusion is characterized by enhanced tail diffusion coupled with an electrically inactive immobile peak. The immobile peak is due to clustering of boron in the presence of excess interstitials which also enhance boron diffusion in the tail region. We present a simple model for the f...

The effect of boron on heterocystous and nonheterocystous dinitrogen fixing Cyanobacteria was examined. The absence of boron in culture media inhibited growth and nitrogenase activity in Nodularia sp., Chlorogloeopsis sp., and Nostoc sp. cultures. Examinations of boron-deficient cultures showed changes in heterocyst morphology. However, cultures of nonheterocystous Cyanobacteria, Gloeothece sp....

Liquids condensing on solids can form a pattern known as ‘‘breath figures.’’ Here we report similar patterns for liquid boron oxide droplets formed by high temperature oxidation reaction of boron nitride. Boron oxide does not wet boron nitride, so the liquid B2O3 oxide forms small droplets. As oxidation proceeds at 12001C, the oxide created by reaction on the surface migrates to existing drople...

The effect of boron on nitrogenase activity has been studied. When cells were dependent on N(2) fixation, the lack of boron inhibited nitrogenase activity. However, under anaerobic conditions or in the presence of Na-dithionite this effect was not observed. Nitrogenase synthesis was not affected by boron deficiency. Similarly, the heterocyst number was not altered. Examination of boron-deficien...