Butte College

ABSTRACTAlcohol withdrawal directly impacts the brain’s stress and memory systems, which may underlie individual susceptibility to persistent drug and alcohol-seeking behaviors. Numerous studies demonstrate that forced alcohol abstinence, which may lead to withdrawal, can impair fear-related memory processes in rodents such as extinction learning, however the underlying neural circuits mediating these impairments remain elusive. Here, we tested an optogenetic strategy aimed at mitigating fear extinction impairments in male c57BL/6 mice following exposure to alcohol (i.e., ethanol) and forced abstinence. In the first experiment, extensive behavioral extinction training in a fear-conditioned context was impaired in ethanol-exposed mice compared to controls. In the second experiment, neuronal ensembles processing a contextual fear memory in the dorsal hippocampus were tagged and optogenetically reactivated repeatedly in a distinct context in ethanol-exposed and control mice. Chronic activation of these cells resulted in a context-specific, extinction-like reduction in fear responses in both control and ethanol-exposed mice. These findings suggest that while ethanol can impair fear extinction learning, optogenetic manipulation of a fear engram is sufficient to induce an extinction-like reduction in fear responses.

Almond leaf scorch is a bacterial disease that kill otherwise healthy trees -- or, if undetected and untreated, entire orchards -- within just a few years. Learn to recognize the disease and take action early to save your trees and your livelihood.

Current recommendations, nationally and internationally, are to eat more vegetables and fruits. Improving the intake of vegetables and fruits remains an important public health challenge, especially for children. The objective of this observational, cross sectional study was to determine vegetable intake in a sample of multi‐ethnic children and examine the influence of flavor enhancers on vegetable intake. The setting was 2 elementary schools in northern California in the spring of 2006. The sample included 181 third and fourth graders of mixed ethnicities. Children were served a 2‐ounce portion of 5 different vegetables, every other day for 2 weeks, with a one‐week break between the two‐week periods for a total of 15 exposures in approximately 10 weeks. Vegetables were served plain and then with two different flavor enhancers. There were no significance differences in vegetable intake based on school, grade, ethnicity and gender. A period effect was found in total amount change. As a result, we used data from the first two periods and modeled the amount of vegetables eaten to determine any differences in the three groups while controlling for gender, school and ethnicity. There was a significant difference between vegetable intake alone versus vegetable with flavor enhancers(p<.0001). For romaine, broccoli and celery, there was a significant difference with flavor enhancer one (p<.003), and for green beans with flavor enhancer two (p=.0003). This study has implications for improving vegetable intake in children.

Pitzer's ion interaction model has been widely accepted for calculating the thermodynamic properties for electrolytes at high ionic strength. For weak electrolytes, a better estimation can be obtained by combining the model with chemical equilibria. The method of calculation is to treat each individual species as a single, separated ion. The concentration of each ion will be constrained by the mass balance equation and its activity will be guarded by the stability constants. Including chemical equilibria in Pitzer's model provides not only a better estimation of the thermodynamic properties of weak electrolytes but also a better understanding of the equilibrium among the complexes. The results may be used for correcting the effect from high ionic strength solution when determining the stability constants. When considering chemical equilibria, some of the parameters reported by Pitzer may have to be reestimated. The method of estimation and comparison between final results are presented. The binary system of HF, and the ternary systems of CuCl2 in NaCl and in HCl are used for demonstration.

In the mid-1700s a debate raged between Jean d’Alembert, Leonhard Euler, and Daniel Bernoulli concerning the proper solution to the classical wave equation. This controversy was partially solved by Lagrange and, more conclusively, by Fourier (50 years later) and it provides an interesting case study for the role of mathematics in the modeling of physical phenomena. Of particular note in this debate, was the meaning of boundary conditions. The controversy is summarized from the point of view of this mathematical physics perspective.