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The interplay between the topology of cortical circuits and synchronized activity modes in distinct cortical areas is a key enigma in neuroscience. We examined the relation between the stable synchronized activity modes and network connectivity using a Hodgkin-Huxley based, brain dynamics model. Simulations indicate that small motifs exhibit different synchronization modes depending on their local parameters. Thus the activity of a complex network composed of interconnected motifs cannot be extracted from the activity mode of each individual motif and is governed by local parameters. We demonstrate that the mechanism governing the synchronized activity modes in neural networks is the greatest common divisor of network loops. The synchronized mode and the transients to synchronization pinpoint the type of external stimuli. These analytic results are supported by in vitro experiments on cultured cortical cells, simulations of neural networks, simulations of chaotic maps, self-consistent and mixing arguments as well as analytical solutions of Bernoulli maps. Our findings call for reexamining sources of correlated activity in cortex and its functions.

Cells grow and divide, doubling their entire content in the process. Proteins are an indispensable part of the cell’s content, and are synthesized by ribosomes. In particular, ribosomes synthesize ribosomal proteins – i.e., their own building blocks. And so, if a cell is to double, ribosomes are to double themselves as they double the proteome. Theoretical limits on the doubling time of cells, and on the required fraction of ribosomal proteins in the proteome, follow. We show that these limits are sensitive to coarse features of the ribosome, and present an array of evidence for their formative power on ribosome architecture in numerous organisms and in organelles.

There is a need to improve and promote the scientific inquiry on the study and use of botanicals, natural products and Chinese Medicine, in order to secure global acceptance. Although there is an enormous history of use of Chinese medicines a better understanding of these preparations and formulae within the scientific and international community is needed. The aim is to present case studies on select botanicals and natural products to provide scientific data that could substantiate the health claims. One example is the inhibition of ENOX2 (tNOX), a molecular target to examine anticancer activity of green tea catechins. The relation between green tea catechins and cell protection through a cell surface protein, ENOX2 has been identified. When the ENOX2 of cells is inhibited, the cells fail to enlarge after division, cease to divide, and after a few days undergo apoptosis. To date, EGCg in green tea is the most effective polyphenol ENOX2 blocker found without any adverse effects on normal cells. Synergistic combinations of green tea concentrate and powdered Capsicum reduces oxidative stress as an approach to elimination of malignant cells in both cancer (HeLa) and non-cancer (MCF-10A) cells. Some preliminary data on green tea and other examples of well-known botanical medicines descibed in Chinese folklore will be presented.