Logical gates in actin monomer

© 2017 The Author(s). We evaluate information processing capacity of a single actin molecule by calculating distributions of logical gates implemented by the molecule via propagating patterns of excitation. We represent a filamentous actin molecule as an excitable automaton network (F-actin automaton). where every atom updates its state depending on states of atoms its connected to with chemical bonds (hard neighbours) and atoms being in physical proximity to the atom (soft neighbours). A resting atom excites if a sum of its excited hard neighbours and a weighted sum of its soft neighbours belong to some specified interval. We demonstrate that F-actin automata implement OR, AND, XOR and AND-NOT gates via interacting patterns of excitation. Gate AND is the most common gate and gate XOR is the rarest. Using the architectures of gates discovered we implement one bit half-adder and controlled-not circuits in the F-actin automata. Speed and space values of the F-actin molecular computers are discussed

Defining mechanisms of actin polymerization and depolymerization during dendritic spine morphogenesis

Dendritic spines are small protrusions along dendrites where the postsynaptic components of most excitatory synapses reside in the mature brain. Morphological changes in these actin-rich structures are associated with learning and memory formation. Despite the pivotal role of the actin cytoskeleton in spine morphogenesis, little is known about the mechanisms regulating actin filament polymerization and depolymerization in dendritic spines. We show that the filopodia-like precursors of dendritic spines elongate through actin polymerization at both the filopodia tip and root. The small GTPase Rif and its effector mDia2 formin play a central role in regulating actin dynamics during filopodia elongation. Actin filament nucleation through the Arp2/3 complex subsequently promotes spine head expansion, and ADF/cofilin-induced actin filament disassembly is required to maintain proper spine length and morphology. Finally, we show that perturbation of these key steps in actin dynamics results in altered synaptic transmission

The effect of spreading depression on the consolidation of learning

The consolidation of an interhemispherically transferred avoidance response was studied using spreading depression to control transfer and consolidation times. Transmission of the learning required 3 min. The length of time following transfer when consolidation could be disturbed varied with the duration of spreading depression, from 3 min to 2 hr. The effect appears not to be due to disruption of neural firing, but to the cortical potential change caused by spreading depression since a pulsating cathodal current (8.5 [mu]A/mm2) passed through medial (but not anterior, lateral, or posterior) cortex can abolish retention. It is suggested that the consolidation process may require electrical potential gradients in the cortex and that it is disturbed by agents which decrease or reverse them.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33480/1/0000885.pd

Spine neck plasticity regulates compartmentalization of synapses

Dendritic spines have been proposed to transform synaptic signals through chemical and electrical compartmentalization. However, the quantitative contribution of spine morphology to synapse compartmentalization and its dynamic regulation are still poorly understood. We used time-lapse super-resolution stimulated emission depletion (STED) imaging in combination with fluorescence recovery after photobleaching (FRAP) measurements, two-photon glutamate uncaging, electrophysiology and simulations to investigate the dynamic link between nanoscale anatomy and compartmentalization in live spines of CA1 neurons in mouse brain slices. We report a diversity of spine morphologies that argues against common categorization schemes and establish a close link between compartmentalization and spine morphology, wherein spine neck width is the most critical morphological parameter. We demonstrate that spine necks are plastic structures that become wider and shorter after long-term potentiation. These morphological changes are predicted to lead to a substantial drop in spine head excitatory postsynaptic potential (EPSP) while preserving overall biochemical compartmentalization

Vývoj organizace řízení města Benešova

Práce se snaží na pozadí historického vývoje města Benešova zachytit všechny skutečnosti ovlivňující formy řízení tohoto města jako vzor řízení poddanských měst, kde vliv majitele na život ve městě byl poněkud jiný, než u měst v majetku panovníka.Dokončená práce s úspěšnou obhajobo

Parental Gender Preferences of an Anticipated Child

Liberal Arts and Humanities - Social Sciences ModuleStudium humanitní vzdělanosti - Společenskovědní modulFaculty of HumanitiesFakulta humanitních studi

Harassment of female and male high school and university students by teachers - comparison

The goal of my thesis is to compare the density and perception of sexual harrasment by teachers at high schools and universities. In the theoretical part of my work I present the concepts which I am basing my thesis at. I explain the evolution of the term sexual harassment and its multiple definitions. I also discuss the meaning and role of education in the society and the specifics of sexual harrasment in a relationship of a student and their teacher. Finally, I also review relevant Czech and international studies. The empirical part of my thesis is based on two studies by the Department of Gender Studies - one being concentrated on high schools, second at universities. I compare and interpret selected data. I focus primarily on the difference between the occurence of sexual harassment at both levels of education and how it is perceived. I also interpret the gender differences