Seed Cleaning and Treating Pays Off

Seed cleaning and treating is imperative- whether you do it yourself or have it done for you. It pays off in increased stands, fewer weeds and less trouble from certain diseases in oats, wheat, barley, flax, and rye

RNA Polymerase-Binding and Transcription Initiation Sites Upstream of the Methyl Reductase Operon of Methanococcus vannielii

RNA Polymerase, purified from Methanococcus vannielii, was shown by exonuclease III footprinting to bind to a 49-base-pair (bp) region of DNA in the intergenic region upstream of mcrB. Sl nuclease protection experiments demonstrated that transcription Initiation in vivo occurs within this region at 32 or 33 bp 5' to the A T G translation initiation codon of mcrB and 19 or 20 bp 3' to a T A T A box

Farm Disease Outlook for 1953

Plant diseases have given us trouble for a long time, and they\u27ll be with us in one form or another in 1953. Here are the highlights of what may happen under different conditions and, in turn, what to do

Multiplexing rhythmic information by spike timing dependent plasticity

Rhythmic activity has been associated with a wide range of cognitive processes. Previous studies have shown that spike-timing-dependent plasticity can facilitate the transfer of rhythmic activity downstream the information processing pathway. However, STDP has also been known to generate strong winner-take-all like competitions between subgroups of correlated synaptic inputs. Consequently, one might expect that STDP would induce strong competition between different rhythmicity channels thus preventing the multiplexing of information across different frequency channels. This study explored whether STDP facilitates the multiplexing of information across multiple frequency channels, and if so, under what conditions. We investigated the STDP dynamics in the framework of a model consisting of two competing subpopulations of neurons that synapse in a feedforward manner onto a single postsynaptic neuron. Each sub-population was assumed to oscillate in an independent manner and in a different frequency band. To investigate the STDP dynamics, a mean field Fokker-Planck theory was developed in the limit of the slow learning rate. Surprisingly, our theory predicted limited interactions between the different sub-groups. Our analysis further revealed that the interaction between these channels was mainly mediated by the shared component of the mean activity. Next, we generalized these results beyond the simplistic model using numerical simulations. We found that for a wide range of parameters, the system converged to a solution in which the post-synaptic neuron responded to both rhythms. Nevertheless, all the synaptic weights remained dynamic and did not converge to a fixed point. These findings imply that STDP can support the multiplexing of rhythmic information and demonstrate how functionality can be retained in the face of continuous remodeling of all the synaptic weights.Comment: 14 pages, 7 figure