The Sometimes Context-Specific Habituation: Theoretical Challenges to Associative Accounts.

A substantial corpus of experimental research indicates that in many species, long-term habituation appears to depend on context-stimulus associations. Some authors have recently emphasized that this type of outcome supports Wagner's priming theory, which affirms that responding is diminished when the eliciting stimulus is predicted by the context where the animal encountered that stimulus in the past. Although we agree with both the empirical reality of the phenomenon as well as the principled adequacy of the theory, we think that the available evidence is more provocative than conclusive and that there are a few nontrivial empirical and theoretical issues that need to be worked out by researchers in the future. In this paper, we comment on these issues within the framework of a quantitative version of priming theory, the SOP model.

SOP- habituation laboratory: An interactive tool for simulating the basic behavioral features of habituation.

This paper presents an open-source online tool for introducing psychology students to the major theoretical and empirical facts of habituation. The tool was designed in a way that combines theory and data through simulated experiments. The simulations exemplify how the priming theory of Allan R. Wagner accounts for the set of behavioral characteristics of habituation proposed by Richard F. Thompson and W. Alden Spencer in 1966. Through this interactive platform, the user can learn the basics of the theory and examine how it accounts for the empirical facts with different parameters. Instructions and commands are provided in three languages: English, Spanish, and Portuguese.

A Simple and Low-Cost, but Naturalistic Method for Introducing Students to Action Potentials

Abstract Current trends in science education recommend the complementary use of virtual and hands-on methods of teaching. In neurobiology, for instance, there is a plethora of virtual laboratories and simulators that can be readily combined with traditional physical labs. Unfortunately, physical laboratories are almost unaffordable for many institutions due to the high cost of equipment. In this paper, we present a simple and low-cost in vivo method for demonstrating some of the basic biophysical properties of neural action potentials. The method involves the following steps: a) dissection of the ventral nerve cord of earthworm; b) electrical stimulation; c) amplification and visualization of the medial and lateral giant fibers' action potentials; and d) recording. The system showed stability, expected amplification, high signal-to-noise ratio, and an estimated total cost of US$ 5.662. We provide guidelines for assembling the system and discus its utility as a teaching alternative for low budget institutions.

Parametric sensitivity analysis for temperature control in outdoor photobioreactors.

In this study a critical analysis of input parameters on a model to describe the broth temperature in flat plate photobioreactors throughout the day is carried out in order to assess the effect of these parameters on the model. Using the design of experiment approach, variation of selected parameters was introduced and the influence of each parameter on the broth temperature was evaluated by a parametric sensitivity analysis. The results show that the major influence on the broth temperature is that from the reactor wall and the shading factor, both related to the direct and reflected solar irradiation. Other parameter which play an important role on the temperature is the distance between plates. This study provides information to improve the design and establish the most appropriate operating conditions for the cultivation of microalgae in outdoor systems.

Comparative energy life-cycle analyses of microalgal biomass production in open ponds and photobioreactors.

An analysis of the energy life-cycle for production of biomass using the oil-rich microalgae Nannochloropsis sp. was performed, which included both raceway ponds, tubular and flat-plate photobioreactors for algal cultivation. The net energy ratio (NER) for each process was calculated. The results showed that the use of horizontal tubular photobioreactors (PBRs) is not economically feasible ([NER]<1) and that the estimated NERs for flat-plate PBRs and raceway ponds is >1. The NER for ponds and flat-plate PBRs could be raised to significantly higher values if the lipid content of the biomass were increased to 60% dw/cwd. Although neither system is currently competitive with petroleum, the threshold oil cost at which this would occur was also estimated.