IPA Awardees for May 2012

James Christopher S. Pang, Johnrob Y. Bantang and Christopher P. Monterola
National Institute of Physics
College of Science
UP Diliman

Effect Of Random Link Malfunctions to Synchronization of Hodgkin- Huxley Neurons in a Lattice Network. Pang JCS, Bantang JY, Monterola CP (2012). International Journal of Modern Physics C, Vol 23(No. 03), page 1250027. DOI: 10,1142/S0129183112500271.

Experimental evidence suggests that information processing by the brain is controlled by the synchronization of large populations of neurons, and such synchronization is also involved in a variety of cognitive functions, such as working memory and perpetual awareness. Moreover certain brain disorders and neurodegenerative diseases, such as autism, epilepsy, schizophrenia, Alzheimer’s disease and Parkinson‘s disease attack large-scale, function-critical neural network which promotes abnormalities in its synchronization. Motivated by these results and the many biological applications of networks, we numerically examine the response of a network of realistic HodgkinHuxley (HH) neurons in lattice configuration under different coupling strengths (g) and neuronal connection malfunctions. We show that random connection malfunctions can at some point effectively enhance the synchronization of the HH network. Aside from its simplicity, understanding neuronal network in a lattice will provide computational groundwork on future implementations of creating networks of neurons in vivo and in vitro. Initial procedures on howto do these experiments are now realizable because of the possibility of allowing single neurons to be physically cultured in nano-tube-based electrode arrays composed of ce||­alluring carbon nanotube islands. This novel method, which has generated signiticant attention, provides a means for precise measurement ofthe dynamics of transmitted signals during neuronal growth. We present here a model platform that can complement the above experimental procedure.

Link to the article http://adsabs.harvard.edu/abs/2012IJMPC..2350027P

Augusto E. Serrano Jr.  and Sharon Nunal
College of Fish and Ocean Sciences
UP Visayas

Production and characterization of phytase from Bacillus spp. as feed additive in aquaculture. Dechavez, R.B., Serrano Jr., A.E., Nunal S., Caipang C.M.A. 2011.
AACL Bioflux 4(3):394-403.

A certain bacteria in powder form is being sold to be added to fish/shrimp feeds to increase phosphorus digestibility for fish growth. But since this is imported and expensive, we tried to screen other Bacillus bacteria other than the commercial one to find out if they are as efficient and cheaper. So we tested four other species and found out the B. megaterium is the best of the bacteria tested. This could be applied to fish/shrimp feeds to increase the availability of phosphorus for growth, saving on the addition of mineral phosphorus which is an expensive ingredient in the formulation of animal feeds. Also, since phosphorus has been one of the two culprits for water pollution because of its low digestibility especially in plant ingredients, it is released by the bacterial enzyme for the growth of the fish/shrimp and its deposition at the bottom is avoided. In this sense, it contributes to making aquaculture a sustainable endeavor.

Irene Crisologo, Christopher P. Monterola and Maricor Soriano
National Institute of Physics

College of Science
UP Diliman

Statistical Feature-Based Craquelure Classification. l. Crisologo, C. Monterola, M. Soriano, International Journal of Modern Physics C, Vol. 22, No. 11 (2011) 1191-1209.DOI: 10.1142/8012918311101683X.

Link to the article http://adsabs.harvard.edu/abs/2011IJMPC..22.1191C