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It is not a regression (not at this stage of the paper, a regression will be done latter) The only complicated thing to understand is $b_i$, which is the 'base relatedness', ie how $i$ is related to a random individual (to be compared to how related it is to individuals with whom it interacts). To simplify let's first consider the situation where $b_i = ...


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Noting that the right hand side can also be written $\mathbf{G}\mathbf{P}^{-1}\mathbf{s}$, we see that the only theoretical limitation of the multivariate breeders equation is the invertibility of the matrix $\mathbf{P}$. This happens when the measures of two traits are the same for all individuals, making two columns of the matrix the same I.e. It becomes ...


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The growth of blood vessels is called angiogenesis. This process occures during embrional development, tissue repair, and even tumor formation (in fact this is a crucial step for tumors to survive). This Nature review provides great overview of the process, I'll try and briefly summarize things: In general large arteries grow circumferential to keep up ...


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Most likely, you can't assume that $h/k$ might be constant. Reason is that those parameters are characteristics of two very separate systems. Thermal conductivity shows how fast heat can be propagated through material. That is, it answers question: if block of metal has $T_0$ temperature on its surface A, and you apply temperature $T_1$ (higher) to opposite ...


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Evolution Evolution is the accumulation of genetic mutations that results in phenotypic variation (physical characteristics) where surviving variations are more suited to the environment the organism lives in, thus allowing it to survive better and -- critically -- reproduce as-good-as or better-than its competing organisms. In terms of computer ...


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Please note that these are just analogies not exact definitions. Okay so let's imagine DNA as string of 4 letters that is the program code of an organism. Also the running environment is a good analogue to the biological environment (RAM, CPU time, disk space - as resources like food, water etc.) Genes of organism could be imagined as methods of an object ...


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The writings by Samir Okasha (philosopher of biology/science) could be a good starting point. In his book Evolution and the Levels of Selection, he explicitly uses the Price equation to discuss selection at multiple levels (e.g. chapter 2.3: Price's equation in a hierarchical setting), and also derives a multi-level version of the Price equation: ...


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I was doing some more research and stumbled upon this paper here by Dr. Izhikevich that describe neurons as a system that can exhibit resonance. The author built a model that he calls the resonate and fire, which is a linear piece-wise model of a neuron. The interesting thing, and why I bring it up, is it can respond to a "two inhibitory pulses, that if ...


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Short answer Action potentials are always generated after a depolarization step. Background Action potentials are generated by prior depolarization of a neuron, typically by the action of an excitatory neurotransmitter. An action potential is per definition a sharp depolarization, followed by a somewhat slower re-polarization step. The most important step ...



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