Induction of serum borne immunomodulatory factors in B6C3F1 mice by carbon tetrachloride. Exposure to carbon tetrachloride produces an increase in B-cell number and function

Carbon tetrachloride exposure in mice induces a serum associated immunosuppressive factor(s) that inhibits T-cell dependent immune responses. The objective of the present studies was to characterize the immunomodulatory activity of serum isolated from carbon tetrachloride-treated mice on T-cell independent humoral immune responses. Direct addition of serum isolated from carbon tetrachloride-treated mice (500 mg/kg/day for 7 days) to naive spleen cell cultures enhanced the antibody forming cell response to lipopolysaccharide as compared to serum from naive or vehicle-treated mice. Enhanced antibody forming cell responses were also observed when spleen cells isolated from carbon tetrachloride-treated mice were sensitized with this T-cell independent antigen 24 h, but not 48 h or 72 h, following exposure of mice to one dose of 500 or 1000 mg/kg of carbon tetrachloride. Additionally, spleen weight and spleen:body weight ratio were increased in mice sensitized in vivo with sheep red blood cells 24 h after exposure to a single dose of carbon tetrachloride (500 or 1000 mg/kg) as compared to naive antigen sensitized mice and mice sensitized 48 and 72 h after exposure to carbon tetrachloride. Fluorescence activated cell sorting analysis indicated that daily exposure to carbon tetrachloride (250 or 500 mg/kg for 7 days) increased the percentage of B-cells in the spleen without altering the number of TH-cell or TC/S cell populations. Taken together, these results suggest that exposure to carbon tetrachloride induces a serum borne factor(s) that produces a modest increase in the functional activity and number of B-cells in the spleen.     

Synergy between Advanced Composites and New NDI Methods

A D Sight Aircraft Inspection System (DAIS 500) large area composite impact damage detection capability has been demonstrated using several structures. In order to obtain equivalent impact damage depths, the IM7/5250-4 structures had to be subjected to much higher impact energies than conventional AS4/3501-6 structures. It is postulated that the application of DAIS with its better than visual inspection sensitivity could lead to both increased design allowables and an alternate approach to certification of composite structures based on impact cumulative probability of occurrence. Further evidence of impact indent depth relaxation (over 30%) was observed. Indent relaxation may have significant implications with respect to the airworthiness of composite structures designed to BVID (barely visible impact damage) limits since this relaxation makes the damage site less apparent.     

Response latency detection of fakers on personnel tests.

Examined the ability of personnel test item response latencies to differentiate between individuals instructed to fake and those instructed to respond honestly with 64 undergraduates in Exp 1 and 100 unemployed Ss in Exp 2. Results supported a general model of lying derived from schema theory, demonstrating that fakers take relatively longer than honest respondents to admit to delinquent characteristics concerning themselves. Discriminant function analysis indicated that response latencies to items on standard personnel tests could significantly distinguish between fakers and honest test respondents in a personnel testing scenario. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verschleiß und Verschleißschutz beim Spritzgießen

Wear and Wear Protection for Injection Moulding Increased power installations at injection moulding machines for higher polymer output rates require improved wear protection measures since the so called ?standard steels”? cannot cope with these demands. This publication describes the adhesive, abrasive and corrosive wear phenomena which are taking place in plasticating units of injection moulding machines as well as the causing factors and resulting effects by means of examples. The influence of different polymers and additives on the service life of the machinery components is also being considered. Finally the article presents solutions to achieve an effective reduction of wear by processing and design related measures, suitable metal surface treatment and adequate material selection for the plasticating unit.     

Introduction to the special series: Cognitive and academic issues related to chronic illness.

The articles in this special series were written by a group of distinguished investigators whose research represents a broad range of illness groups and disciplines for the purpose of integrating literature and addressing the mechanism by which a chronic disease may result in learning problems. Within the limitations of a scholarly journal, not every illness type was included. Rather, specific disease types were chosen in which school psychologists are apt to have frequent contact with these children and where the diseases are frequently associated with learning problems. Another purpose of this special volume is to bring together a variety of perspectives within the field in the hope of stimulating additional dialogue among school psychologists and pediatric psychologists, and other health care providers. Finally, it is hoped that such a collection will encourage clinical researchers to consider School Psychology Quarterly as a forum for the exchange of scholarly research within the fields of chronic illness and disorders related to learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation of eighth graders' family structure, gender, and family environment with academic performance and school behavior.

[Correction Notice: An erratum for this article was reported in Vol 80(3) of Journal of Educational Psychology (see record 2008-10692-001). Table 2 contained incorrect data. The first column of data contained correlations whose signs should have been reversed. The complete correct table appears in the erratum.] The purpose of this study was to assess how family structure, gender, and family environment were related to both academic performance (end-of-the-year grades and quantitative and verbal achievement factor scores) and school behavior (number of days absent, number of days tardy, and number of in-school detentions). Subjects were 219 middle-class eighth graders (96 boys, 123 girls). Generally, students in two-parent nuclear families had better academic performance and less problematic school behavior than did students in either mother-custody or stepfather families. Boys had more detentions than did girls. Despite significant differences among the three family structures, the family structure variable accounted at most for only 7% of the variability in academic performance and school behavior. A family environment that emphasized achievement and intellectual pursuits accounted for variability in end-of-the-year grades beyond that accounted for by family structure, gender, and family conflict. The joint consideration of family structure, gender, and family environment accounted at most for 17% of the variance in academic performance and school behavior. For students in the mother-custody and stepfather families, contact with father was unrelated to academic performance. Findings are discussed in terms of models of achievement motivation and behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using tests as learning opportunities.

The present study assessed the value of test-taking as a means of increasing, rather than simply monitoring, learning. One hundered and five college students read a short essay about the American Civil War and were then given either an initial test or no test about the text material. The form of the initial test was either fill-in or multiple-choice; and the knowledge examined was either directly stated in the original text (verbatim) or could be logically derived (inferential) from the text. A common final test, containing all of the above item types, was given to all students two days later. Scores on the final test indicated that in general, those students who did the initial test performed better than the control students, which indicates the potential value of tests as learning experiences. Furthermore, the enhancement provided by the initial test varied with the different test techniques: It was greater for fill-in than for multiple-choice forms and greater for inferential than for verbatim knowledge. It is suggested that teachers make use of the learning potential of tests and construct them so as to maximize the kind of learning desired. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of misleading questions in promoting nonconservation responses in children and adults.

In three studies we demonstrated that adults as well as children provide nonconservation-of-weight responses to misdirecting questions. The effect was constant over the types of problems studied, did not vary over the grade range tested (third graders through college students), and was resistant to a condition that had earlier proved successful in breaking a set to respond to misleading implications of questions. The results underscore the importance of linguistic pragmatics, conflicts with recent claims that among adults there is a certainty about and a belief in the necessity of certain types of Piagetian logic, and support earlier findings suggesting that contextual cues can alter responses to conservation questions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)