Recording from the Aplysia Abdominal Ganglion with a Planar Microelectrode Array

A passive multimicroelectrode array has been fabricated and used to record neural events from the abdominal ganglion of the marine mollusk, Aplysia californica. The array consists of a pattern of gold conductor lines on a glass substrate which is insulated with a polyimide. The 32 electrodes are 25, in diameter and are arranged in a 4 x 8 matrix on 200 um centers. The array is durable and reusable, and can be safely autoclaved. The recording environment surrounding each electrode is sufficiently uniform so as to permit spatial localization of identified cells in the ganglion. The array can record large numbers of unique and often interrelated extracellular neural potentials in relatively simple experiments.     

Do alcohol expectancies mediate drinking patterns of adults?

Compared the reinforcement expectancies of adult alcoholics with beliefs of 2 other adult populations. 171 participants (mean age 42.8 yrs) in alcohol treatment programs, 65 hospitalized medical patients (mean age 42.6 yrs), and 344 college students (mean age 24 yrs) identified their beliefs about the consequences of alcohol consumption through an alcohol expectancy questionnaire (AEQ). Results indicate that the previously defined AEQ beliefs among nonalcoholic populations identified by S. A. Brown et al (1980) and B. A. Christiansen et al (see record 1982-25609-001) are applicable to alcoholic populations. In the present study, nonalcoholics and alcoholics differed significantly in terms of their alcohol expectancies. In general, alcoholics were found to maintain strong alcohol expectancies, and expectancies increased across and within populations as a function of drinking patterns. Theoretical, research, and clinical implications of these findings and the AEQ are discussed. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Male preferences for unmated versus mated females in two species of voles (Micotus ochrogaster and M. montanus).

Examined male preference for unmated vs mated females in 2 species of voles, using 73 prairie voles and 78 montane voles in 2 testing situations each. In Exp I, conducted in a tether test situation, prairie voles spent significantly more time and copulated more with unmated than with mated females. In Exp II, male prairie voles spent significantly more time visiting and investigating anesthetized unmated females than anesthetized mated females. In Exp III, male montane voles showed no significant visitation or copulatory preference for unmated vs mated females in the tether situation. In Exp IV, male montane voles spent more time with unmated, anesthetized females than mated females but displayed no other significant differences. In general, male prairie voles appeared more discriminating in their mate choice than male montane voles. These differences are consistent with differences in male parental effort in the field. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chronic stress impairs rat spatial memory on the Y maze, and this effect is blocked by tianeptine treatment.

Chronic restraint stress causes significant dendritic atrophy of CA3 pyramidal neurons that reverts to baseline within a week. Therefore, the authors assessed the functional consequences of this atrophy quickly (within hours) using the Y maze. Experiments 1–3 demonstrated that rats relied on extrinsic, spatial cues located outside of the Y maze to determine arm location and that rats with hippocampal damage (through kainic acid, colchicine, or trimethyltin) had spatial memory impairments. After the Y maze was validated as a hippocampally relevant spatial task, Experiment 4 showed that chronic restraint stress impaired spatial memory performance on the Y maze when rats were tested the day after the last stress session and that tianeptine prevented the stress-induced spatial memory impairment. These data are consistent with the previously demonstrated ability of tianeptine to prevent chronic stress-induced atrophy of the CA3 dendrites. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Story and list recall tests as measures of verbal memory in a head-injured sample.

Memory components of story and list recall were derived for 48 head-injured patients (mean age 33.5 yrs) using regression techniques. Ss completed such measures as the Wechsler Memory Scale. General and verbal memory components, respectively, contributed the most variance to both story and list recall under both immediate and delayed conditions. Although they share substantial variance, list and story recall were not identical. Willingness to repeat oneself contributed to all types of recall, except delayed story recall. It was hypothesized that long-term storage contributed to immediate list recall ability, active semantic organization contributed to delayed list recall ability, and attentional fluctuations contributed to delayed story recall ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Wireless security policies

Security policies: The phrase that strikes fear in the hearts of many security professionals. Policy and policy enforcement is a critical part of any organization’s security posture. Unfortunately, many administrators find policy mundane or frustrating. When it comes to wireless security, a clear and complete policy is even more critical. Few other technologies can punch a hole into the core of an organization’s network like wireless. Thankfully for security professionals and their employers, wireless networks are new, interesting, and dangerous enough to actually warrant interest in creating and enforcing a policy.     

Austenite grain growth kinetics in Al-killed plain carbon steels

Austenite grain growth kinetics have been investigated in three Al-killed plain carbon steels. Experimental results have been validated using the statistical grain growth model by Abbruzzese and Lücke, which takes pinning by second-phase particles into account. It is shown that the pinning force is a function of the pre-heat-treatment schedule. Extrapolation to the conditions of a hot-strip mill indicates that grain growth occurs without pinning during conventional processing. Analytical relations are proposed to simulate austenite grain growth for Al-killed plain carbon steels for any thermal path in a hot-strip mill.     

Electrochemical oxidation of adsorbed alkenoic acids as a function of chain length at Pt(111) electrodes. Studies by cyclic voltammetry,EELS and Auger spectroscopy

Studies of the electrochemical oxidation of a series of straight-chain terminal alkenoic acids adsorbed at a Pt(111) electrode surface are reported. Compounds adsorbed were: propenoic acid (acrylic acid, PPA); 3-butenoic acid (vinylacetic acid, 3BTA); 4-pentenoic acid (allylacetic acid, 4PTA); 6-heptenoic acid (6HPA); and 10-undecenoic acid (10UDA). Vibrational spectra of adsorbed layers were obtained by use of electron energy-loss spectroscopy (EELS). Molecular packing densities were measured by use of Auger spectroscopy. Electrochemical oxidation of each adsorbed layer was explored by means of cyclic voltammetry in aqueous inert electrolyte (KF/HF). As the analogous aliphatic acids are not chemisorbed at Pt under the same conditions, the alkenoic acids evidently adsorb at Pt(111) predominantly through the C=C double bond. Molecular packing densities indicate that the carboxylic acid moiety is in contact with the Pt surface only in the case of PPA. EELS spectra also indicate that the carboxylate groups (other than in PPA) are present as pendants. The carboxylic acid O-H stretching bands of most of the adsorbed acids are red-shifted and broadened, evidently due to extensive intermolecular hydrogen bonding; the exceptions are PPA, for which the interaction is primarily with the Pt surface, and 3BTA, for which intermolecular interaction between the carboxylic acid pendants is apparently prevented by steric considerations. The surface-attached carboxylic acid moieties react with KOH solution, leading to retention of K⁺ ions, detected by Auger spectroscopy, and to changes in the vibrational spectra indicative of carboxylate anions; reactivity toward KOH decreases with chain length. Adsorbed alkenoic acids at Pt(111) surfaces are stable in water and in vacuum. Oxidation of the adsorbed short-chain acids PPA and 3BTA proceeds to completion, forming CO₂ as the principal product. Oxidation of the adsorbed long-chain acids converts the C=C moiety to 2CO₂, and transforms the remainder of the molecule to an unadsorbed diacid (likely possibilities are malonic acid from 4PTA; glutaric acid from 6HPA; and heptane-1,7-dioic acid from 10UDA).     

Differential effects of selective immunotoxic lesions of medial septal cholinergic cells on spatial working and reference memory.

The effect of injection into the medial septum of a toxin selective for cholinergic neurons, 192 IgG-saporin, was examined in rats trained to perform 2 versions of the radial 8-arm maze task. Rats were first trained to perform a task with varying delays (0, 1, 2 min) imposed between the 4th correct arm choice and access to all 8 arms. Lesioned rats made significantly more errors in the first 4 choices compared with controls and significantly more errors after delays; however, this effect was not delay dependent. Rats were then trained on a different version of this 8-arm maze task in which they learned to avoid 2 arms that were never baited. There was no treatment effect on acquisition of this task. These data are consistent with the hypothesis that the cholinergic projection to the hippocampus facilitates the acquisition of information into the system responsible for short-term memory for locations visited (spatial working memory) but is not involved in retention of this information. It also appears to play no role in either the acquisition or retention of place-nonreward associations (spatial reference memory). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social skills of and social environments produced by different Holland types: A social perspective on person€nvironment fit models.

Acritical aspect of the environment in person–environment models is the nature and density of the social interactions of the members who populate the environment. Because social types solve problems through social mechanisms, it was hypothesized that they would have greatest skills in social coping and that the further the Euclidean distance (in Holland's hexagon) from social, the lower the skill level would be in these social skills. It was also hypothesized that there would be no differences among Holland types in skill level for problem-focused social skills. On the basis of an assessment of vocational interests and self-reported social skills of 134 undergraduates, these hypotheses were corroborated. Chemistry laboratory groups were qualitatively studied to describe the social interaction environment of persons with relative deficits in the social-coping skills. These chemists interacted often, enjoyed and benefited from the interactions, but constrained their social interactions to minimize the dependence on social-coping social skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)