Visual spatial memory is enhanced in female rats (but inhibited in males) by dietary soy phytoestrogens

Background  

In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined.     

A potential source of free radicals in iodine-based chemical oscillators

The iodide-peroxide system in an acidic medium was investigated as a potential source of free radicals in iodine-based chemical oscillators. The radicals were detected by EPR spin-trapping using spin-trap 5-(tert-butoxycarbonyl)-5-methyl-1-pyrroline N-oxide (BMPO), which forms stable spin-adducts with oxygen-centered radicals. The iodide-peroxide system is introduced as an easily available laboratory source of free radicals.     

Excessive excitation of hydrogen peroxide during oscillatory chemical evolution

The peculiar reaction dynamics of the Bray-Liebhafsky chemical oscillator is connected with the nonequilibrium periodic excitations of hydrogen peroxide embedded in a hydrogen-bonded water network. This was indicated by Raman spectroscopy that showed periodic, isothermal, and excessive excitation of the symmetric vibration of hydrogen peroxide. Since such an excessive excitation should be the result of a specific nonequilibrium energy distribution with the active participation of water, understanding this process can be of considerable importance in other systems in which water is the main constituent.     

A Rapid and Facile Synthesis of Nanofibrillar Polyaniline Using Microwave Radiation

We present the first fast and facile microwave assisted synthesis of polyaniline (PANI) nanofibers (“MWA synthesis”). Under conventional synthesis (CS), the polymer was produced with 79.7% yield after 5 h at ambient temperature. However, under microwave irradiation, the nanofibers were produced with yield of 76.2% after only 5 min, i.e., with 78.8% after 20 min at ambient temperature. The FTIR and Raman spectra show the PANI structure in all samples either synthesized conventionally or in the microwave. SEM and TEM confirm the nanofibrillar morphology.

     

The application of homotopy analysis method to solve nonlinear differential equation governing Jeffery–Hamel flow

In this paper Jeffery–Hamel flow has been studied and its nonlinear ordinary differential equation has been solved through homotopy analysis method (HAM). The obtained solution in comparison with the numerical ones represents a remarkable accuracy. The results also indicate that HAM can provide us with a convenient way to control and adjust the convergence region.     

Neuromodulation by soy diets or equol: Anti-depressive &; anti-obesity-like influences,age- &; hormone-dependent effects

Background  

Soy-derived isoflavones potentially protect against obesity and depression. In five different studies we examined the influence of soy-containing diets or equol injections on depression, serotonin levels, body weight gain (BW) and white adipose tissue (WAT) deposition in female Long-Evans rats at various stages of life [rats were intact, ovariectomized or experienced natural ovarian failure (NOF)].     

Oxygen centered radicals in iodine chemical oscillators

The existence of free radicals in iodine-based oscillatory systems has been debated for some time. Recently, we have reported the presence of reactive oxygen species (ROS) in the iodide-peroxide system in acidic medium, which is common to all iodine--based oscillatory systems ( J. Phys. Chem. A 2011 , 115 , 2247--2249 ). In this work, the goal was to identify the ROS produced in this system using an EPR spin trap which can distinguish between hydroxyl (HO(?)) and hydroperoxyl (HOO(?)) radicals. The formation of the hydroperoxyl radical was observed and a possible explanation for the low EPR signal of hydroxyl radical was proposed.     

The kinetics of iodide oxidation by hydrogen peroxide in acid solution

The kinetics of the complex reaction between I⁻ and H₂O₂ in acid media was investigated. The particular attention was focused on the determination of the rate constant of the reaction between HIO and H₂O₂ involved in the investigated complex process. The examination of the whole kinetics was performed by simultaneously monitoring the evolution of O₂ pressure, I₃⁻ and I⁻ concentrations. We modeled the behavior of experimentally followed components based on Liebhafsky’s research. Our preliminary results suggest a significantly higher rate constant (3.5 × 10⁷ M⁻¹ s⁻¹) of the reaction between HIO and H₂O₂ as those proposed in the literature.