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Ioannides A.A.,Laboratory for Human Brain Dynamics | Sargsyan A.,Orbeli Institute of Physiology
Proceedings of the IEEE/EMBS Region 8 International Conference on Information Technology Applications in Biomedicine, ITAB | Year: 2010

Ecologically relevant stimuli are rarely used in scientific studies because they are difficult to control. Instead researchers employ simple stimuli with sharp boundaries (in space and time). Here we explore how the rhythmogram can be used to provide the much needed rigorous control of natural continuous stimuli like music and speech. The analysis provides a natural way of correlating important features in the timecourse of stimuli with corresponding features in brain activations elicited by the same stimuli. Correlating the identified regularities of the stimulus time course with the features extracted from the activations of each voxel of a tomographic analysis of brain activity provides a powerful view of how different brain regions are influenced by the stimulus at different times and over different (user-selected) timescales. The application of the analysis to tomographic solutions extracted from Magnetoencephalographic (MEG) data recorded while subjects listen to music reveal a surprising and aesthetically pleasing aspect of brain function: an area believed to be specialized for visual processing is recruited to analyze the music after the acoustic signal is transformed to a feature map. © 2010 IEEE.


Ioannides A.A.,AAI Scientific Cultural Services Ltd. | Sargsyan A.,Orbeli Institute of Physiology
IEEE Transactions on Information Technology in Biomedicine | Year: 2012

Ecologically relevant stimuli are rarely used in scientific studies because they are difficult to control. Instead, researchers employ simple stimuli with sharp boundaries (in space and time). Here, we explore how the rhythmogram can be used to provide much needed rigorous control of natural continuous stimuli like music and speech. The analysis correlates important features in the time course of stimuli with corresponding features in brain activations elicited by the same stimuli. Correlating the identified regularities of the stimulus time course with the features extracted from the activations of each voxel of a tomographic analysis of brain activity provides a powerful view of how different brain regions are influenced by the stimulus at different times and over different (user-selected) timescales. The application of the analysis to tomographic solutions extracted from magnetoencephalographic data recorded while subjects listen to music reveals a surprising and aesthetically pleasing aspect of brain function: an area believed to be specialized for visual processing is recruited to analyze the music after the acoustic signal is transformed to a feature map. The methodology is ideal for exploring processing of complex stimuli, e.g., linguistic structure and meaning and how it fails, for example, in developmental dyslexia. © 2012 IEEE.


Zand N.,Islamic Azad University at Varamin | Foroudi F.,Islamic Azad University at Varamin | Mailova E.,Yerevan State University | Voskanyan A.V.,Orbeli Institute of Physiology | Voskanyan A.V.,OPTIPACK LLC Packages And Packing Machines Manufacturing Yerevan
African Journal of Microbiology Research | Year: 2010

The effect of high frequency Electromagnetic Induction (EMI) combined with various condition of preheating for inactivation of mesophil microorganisms in multilayer flexible pouches has been studied. All samples were filled in pouches and, have been put in (water bath chamber; different condition of pre heating (80°C 5 min, 80°C 10 min, 80°C 15 min, 85°C 5 min, 85°C 10 min, 85°C 15 min) have been done; and ready for EMI sterilization which discharges square-wave pulses with variable voltage 1-20 kV/cm and frequency 8-10 GHz. The spores of these bacteria (gr+) were practically resistant in electric field; however, pre heat caused spore changed its behavior from passive forms (latent) to active forms (vegetative). If cells are cultivated at higher temperature, increasing tendency which can permanently keep fluidity viscosity of the cell membrane before electromagnetic field so EMI efficiency is increased. The populations of mesophil microorganisms depended on type of treatment type of chick type and type of culture. The death ratio of mesophil microorganisms increasing in chick 14200% more than chick meal, chance of negative mesophile microorganism growth in every treatment compares with last treatment increasing 54%. Negative growth in culture "PCA" is 3.3 degree more than culture "PE 2", in culture "PE 2" is 330% more than culture "Cook meat"; how ere these parameter in various thermal processing without EMI was evaluated positive mesophile microorganism growth increasing in chick meal 1905% more than chick type, and chance of passive mesophile microorganism growth in every treatment compares with last treatment decreasing 41% and type culture have no effect on growth of mesophil bacteria. ©2010 Academic Journals.


Simonyan K.V.,Orbeli Institute of Physiology | Chavushyan V.A.,Orbeli Institute of Physiology
Metabolic Brain Disease | Year: 2015

Ovariectomy is known as “surgical menopause” with decreased levels of estrogen in female rodents. Its reported risks and adverse effects include cognitive impairment. The action of hydroponic Teucrium polium on nucleus basalis of Meynert (bnM) neurons following 6 weeks of ovariectomy was carried out. The analysis of spike activity was observed by on-line selection and the use of a software package. Early and late tetanic, − posttetanic potentiation and depression of neurons to high frequency stimulation of hippocampus were studied. The complex averaged peri-event time and frequency histograms were constructed. The histochemical study of the activity of Са2+-dependent acid phosphatase was observed. In conditions of hydroponic Teucrium polium administration, positive changes in neurons and gain of metabolism leading to cellular survival were revealed. The administration of Teucrium polium elicited neurodegenerative changes in bnM. © 2014, Springer Science+Business Media New York.


Chilingaryan A.,Occidental College | Chilingaryan A.,Medical Center | Chilingaryan A.M.,Orbeli Institute of Physiology | Chilingaryan M.,Orbeli Institute of Physiology | Martin G.G.,Occidental College
Microscopy and Microanalysis | Year: 2014

Currently there are no methods available for staining rat and human myocardial microvasculature on thick sections that would allow for specific staining and differentiation of arterioles, venules, and capillaries. A non-injection technique is described that allows for labeling of the microvascular bed (MVB) in formalin-fixed pieces of the myocardium from humans and the white rat Rattus norvegicus, as well as human full-mount pericardium. Vessel staining is based on the activity of phosphatases (ATPases) and the precipitation of the released phosphate with calcium ions at high pH (pH 10.5-11.5). The resulting precipitate subsequently is converted to black or brown lead sulfide. The specificity of this reaction to vessels of the MVB allows arterioles, venules, capillaries, and pre-and postcapillaries to be clearly visualized in thick (60-100 μm) and ultra-thick (300-500 μm) sections against an unstained background of muscle and connective tissue. In addition, smooth muscle cells of arterioles are also stained allowing for differentiation between arteriolar and venular beds. These observations have not been reported in rat or human myocardium using other methods. This procedure should benefit studies of coronary microcirculation in experimental and pathological conditions, as well as in pharmacological investigations. Copyright © 2014 Microscopy Society of America.

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