Complex cognitive behaviors, such as context-switching and rule-following, are thought to be supported by the prefrontal cortex (PFC). Neural activity in the PFC must thus be specialized to specific tasks while retaining flexibility. Nonlinear "mixed" selectivity is an important neurophysiological trait for enabling complex and context-dependent behaviors. Here we investigate (1) the extent to ...

Neurons in the macaque supplementary eye field (SEF) fire at different rates in conjunction with planning saccades in different directions. They also exhibit object-centered spatial selectivity, firing at different rates when the target of the saccade is at the left or right end of a horizontal bar. To compare the rate of incidence of the two kinds of signal, and to determine how they combine, ...

Dopamine is a neurotransmitter implicated in several brain functions, including vision. In the present study, we investigated the impacts of the lack of D2 dopamine receptors on the structure and function of the primary visual cortex (V1) of D2-KO mice using optical imaging of intrinsic signals. Retinotopic maps were generated in order to measure anatomo-functional parameters such as V1 shape, ...

We describe a sequence of experiments investigating the strengths and limitations of Fukushima's neocognitron as a handwritten digit classifier. Using the results of these experiments as a foundation, we propose and evaluate improvements to Fukushima's original network in an effort to obtain higher recognition performance. The neocognitron performance is shown to be strongly dependent on the ch...

In mining projects, the design and production programmes are developed on the basis of a block model. This model requires defining, assessing and assuring many important parameters used in the feasibility study and that may have relevant consequences over the future results of the project. The selection of such parameters is a complex engineering decision due to their great economic impact on t...

Extensive use of classical antibiotics has led to the growing emergence of many resistant strains of pathogenic bacteria. Evidence has suggested that cationic antimicrobial peptides (AMPs) are of greatest potential to represent a new class of antibiotics. The largest group of AMPs comprises peptides that fold into an amphipathic alpha-helical conformation when interacting with the target microo...

Background: Daidzin (glycosidic isoflavone) bioconversion into daidzein (aglyconic increases its bioactivity. This can be carried out using fermentation, a fungus that has been widely used for making tempeh in Indonesia, Aspergillus oryzae. Objective: study aimed to validate the method of analysis and determine content A. oryzae-fermented edamame TLC densitometry. Method: Daidzein determination...

Isotope selective effects in resonance ionization mass spectrometry (RIMS) pose a potentially serious limitation to the application of this technique to the precise and reproducible measurement of isotope ratios. In order to identify some of the underlying causes of isotope selectivity in RIMS and to establish procedures for minimizing these effects, we investigated laser-induced isotope select...

Nanopore size, shape, and surface charge all play important roles in regulating ionic transport through nanoporous membranes. The ability to control these parameters in situ provides a means to create ion transport systems tunable in real time. Here, we present a new strategy to address this challenge, utilizing three unique electrochemically switchable chemistries to manipulate the terminal fu...