Lack of asbestos contamination of paraffin

OBJECTIVE: To investigate possible asbestos contamination of paraffin and migration by asbestos fibers during the tissue-embedding process. DESIGN: Three sample categories were included in the study: (1) commercially available paraffin samples; (2) procedural control samples, which were prepared by processing the paraffin through the use of standard solvents and instruments; and (3) samples taken from areas adjacent to embedded tissue and evaluated for migration of asbestos from the tissue into the surrounding paraffin. The analysis of collected material from all samples was performed with analytical transmission electron microscopy. RESULTS: Only one extremely small tremolite fiber was found in any of the commercially available samples of paraffin. No asbestos fibers were found either in the procedural control samples or in the samples taken adjacent to the embedded lung tissue. CONCLUSIONS: First, it was extremely unlikely that any of the commercial paraffin samples would have skewed data due to embedded tissue. Second, the processing and instrumentation was not found to contribute asbestos material to the paraffin during the preparations. Finally, embedded tissue that contained high numbers of fibers, both uncoated fibers and asbestos bodies, did not contribute asbestos to the adjacent paraffin.     

Aging and strategic retrieval processes: Reducing false memories with a distinctiveness heuristic.

The authors show that a strategic retrieval process--the distinctiveness heuristic--is a powerful mechanism for reducing false memories in the elderly. Individuals studied words, pictures, or both types of items and then completed a recognition test on which the studied items appeared once, whereas the new words appeared twice. After studying either pictures only or a mixture of pictures and words, both younger and older adults falsely recognized fewer repeated new words than did participants who studied words. Studying pictures provided a basis for using a distinctiveness heuristic during the recognition test: Individuals inferred that the absence of memory for picture information indicates that an item is "new." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Placebo-controlled evaluation of abbreviated progressive muscle relaxation and of relaxation combined with cognitive therapy in the treatment of tension headache.

Sixty-six tension headache patients were randomly assigned to one of four conditions for 8 weeks: (a) progressive muscle relaxation (PMR) alone; (b) PMR plus cognitive therapy (PMR?+?Cog); (c) pseudomedication, a credible attention-placebo control; or (d) continued headache monitoring. A comparison of overall headache activity (headache index), derived from a daily headache diary, for 4 weeks before treatment to 4 weeks after treatment revealed that active treatment (PMR and PMR?+?Cog) was superior to either control condition. Moreover, level of headache medication consumption decreased significantly for the active treatment groups. Although headache-index comparisons of the two active treatments showed no advantage for adding cognitive therapy to PMR, a measure of clinically significant change showed a trend for PMR?+?Cog to be superior to PMR alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reduced-order compensators via balancing and central control design for a structural control problem

Real-time control of a physical system necessitates controllers that are low order. In this article, we compare two balanced truncation methods as a means of designing low-order controllers for a nonlinear cable-mass system. The first is the standard technique of balanced truncation. The second, linear quadratic Gaussian (LQG) balanced truncation, can be thought of as balancing based on the controller, and states that are important from the perspective of control and filter design are retained. The control design applied to each reduced-order model is the central controller. We provide an overview of the central controller and devote attention to the design of this controller in the presence of balancing. Also described in this article is a method for reducing computational time in solving algebraic Riccati equations for the design of low-order LQG balanced controllers.     

Stereotypes and retrieval-provoked illusory source recollections.

When expectations and stereotypes are activated at retrieval, they spontaneously create distorted and illusory recollections that are consistent with these expectations. Participants studied doctor (physician)-related and lawyer-related statements that were presented by 2 different people. When informed, on a subsequent source memory test, (i.e., of who presented what) that one of the study sources was actually a doctor and the other source was a lawyer, there was a strong tendency to attribute the test items in a stereotype-consistent manner. In 3 experiments, participants frequently reported recollecting specific details, such as via "remember" judgments, to justify their stereotype-consistent but incorrect responses. These experiments rule out explanations involving either the misattribution of strong familiarity or differences in the bias to making remember responses as accounts for the illusory source attributions. Instead, the illusory recollections are consistent with the notion that recollective experience is manufactured from both the information in the memory trace and information in the retrieval environment, such as an individual's expectations, stereotypes, and general knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Maternal and Postnatal High Linoleic Acid Diet Impacts Lipid Metabolism in Adult Rat Offspring in a Sex-Specific Manner

Linoleic acid (LA), an n-6 polyunsaturated fatty acid (PUFA), is essential for fetal growth and development. We aimed to investigate the effect of maternal and postnatal high LA (HLA) diet on plasma FA composition, plasma and hepatic lipids and genes involved in lipid metabolism in the liver of adult offspring. Female rats were fed with low LA (LLA; 1.44% LA) or HLA (6.21% LA) diets for 10 weeks before pregnancy, and during gestation/lactation. Offspring were weaned at postnatal day 25 (PN25), fed either LLA or HLA diets and sacrificed at PN180. Postnatal HLA diet decreased circulating total n-3 PUFA and alpha-linolenic acid (ALA), while increased total n-6 PUFA, LA and arachidonic acid (AA) in both male and female offspring. Maternal HLA diet increased circulating leptin in female offspring, but not in males. Maternal HLA diet decreased circulating adiponectin in males. Postnatal HLA diet significantly decreased aspartate transaminase (AST) in females and downregulated total cholesterol, HDL-cholesterol and triglycerides in the plasma of males. Maternal HLA diet downregulated the hepatic mRNA expression of Hmgcr in both male and female offspring and decreased the hepatic mRNA expression of Cpt1a and Acox1 in females. Both maternal and postnatal HLA diet decreased hepatic mRNA expression of Cyp27a1 in females. Postnatal diet significantly altered circulating fatty acid concentrations, with sex-specific differences in genes that control lipid metabolism in the adult offspring following exposure to high LA diet in utero.