Post-Event Rumination and Negative Self-Appraisal in Social Phobia Before and After Treatment.

This study investigated the relationship between self-appraisals of performance, symptom severity and post-event rumination in social phobia, and evaluated the effect of treatment on these variables. A socially phobic group and a nonanxious control group performed an impromptu speech and were told that their performance would be evaluated. Participants appraised their performance immediately after the speech and 1 week later, and the frequency of post-event rumination during the week following the speech was assessed. The socially phobic group maintained the negative appraisals of their speech over the week, whereas the nonclinical group showed increased positivity about their performance The socially phobic group also engaged in more negative rumination than controls. Treatment improved perceptions of performance and reduced negative rumination. These results are discussed in the light of cognitive models of social phobia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Baseline Determination in Construction Labor Productivity-Loss Claims

Various ways of quantifying damages have been applied to productivity loss claims in construction. All of the ways attempt to be as objective as possible based on the extent of information available in a particular case. The measured mile, a widely accepted method, is employed when an unimpacted baseline period of production can be identified. Although that approach is considered to be the most objective method available in such cases, the method is limited and does not directly account for variation in individual productivity values about a normal or natural level of productivity. A gap exists between the use of existing methods and the availability of an appropriate methodology that specifically addresses variation in productivity. The key lies in the way baseline productivity is measured, which is inherently statistical, yet no truly statistical methods are used to establish such a baseline. Using the measured mile as a backdrop, this article provides an objective, measurement-based approach that can be used to establish a productivity baseline applied to construction productivity loss claims, based on the application of statistical methods aided by a process control chart. The focus is on providing the basic principles and concepts underlying the approach presented.     

A greedy algorithm to determine the number of transporters in a cyclic electroplating process

This paper presents a local optimization algorithm for minimizing the number of transporters required for material handling in a cyclic processing line. Within a cycle, a given set of transportation operations must be performed. Each operation consists of picking up a work-in-process job at a stage and delivering it to the next stage. The length of time that a job can remain at a particular stage is restricted by a time window. The transporters that perform the operations move on a shared track, and traffic collisions must be avoided during their movements. To avoid traffic collisions, the operations are partitioned into groups, where each group is served by a single transporter. A local optimal solution is obtained when the group sizes are maximized. We show that the duals of the linear programming subproblems formulated in the process of maximizing the group sizes are specially structured shortest-path problems. This leads to an effective search method for the maximization problem. Conditions when die proposed algorithm achieves die global optimal solution are discussed. The algorithm's performance is evaluated on both randomly generated test problems and benchmark problems.     

Relationships between identity formation and computer use among black and white emerging adult females

The purpose of this study was to examine the relationships between computer use, identity formation, and self-esteem among Black and White emerging adult females. One hundred 56 female college students participated in this study by completing a survey that included the Internet/Computer Use Questionnaire, the Ego Identity Process Questionnaire, and the Rosenberg Self Esteem Scale. Racial differences were found between Black and White females with regard to perceived problematic use of the Internet and use of the computer for communication and use of the Internet for schoolwork. In addition, differences between Black and White females were found between identity formation and problematic use of the Internet and between self-esteem and type of use of the Internet. These findings were discussed in relation to future research and interventions.     

Performance evaluation of dynamically linearized and kinematically redundant planar manipulators

The objective of this research is to investigate the feasibility of a theoretical development which could lead to advanced manipulator concepts offering fast dynamic and control features. Specifically, the application of “dynamic linearization” to a kinematically redundant planar manipulator is studied. In comparing such a manipulator with a standard non-linear, non-redundant design it is shown that in addition to the expected merits in linearity, dexterity, and computational simplicity, savings in actuator energy consumption can also be realized using a relative simple trajectory optimization scheme.     

The effect of penicillin on fatty acid synthesis and excretion inStreptococcus mutans BHT

Treatment of exponentially growing cultures ofStreptococcus mutans BHT with growth-inhibitory concentrations (0.2 μg/ml) of benzylpenicillin stimulates the incorporation of [2-¹⁴C] acetate into lipids excreted by the cells by as much as 69-fold, but does not change the amount of¹⁴C incorporated into intracellular lipids. At this concentration of penicillin cellular lysis does not occur. The radioactive label is incorporated exclusively into the fatty acid moieties of the glycerolipids. The increase in the radioactive content of the extracellular lipids reflects an actual net increase in the total fatty acid content as determined by a chemical assay. During a 4-hr incubation in the presence of penicillin, the extracellular fatty acid ester concentration (per mg cell dry weight) increases 1.5 fold, even though there is no growth or cellular lysis. No change is observed in the intracellular fatty acid ester content. An indication of the relative rate of fatty acid synthesis was most readily obtained by placingS. mutans BHT in a buffer containing¹⁴C-acetate. Under these nongrowing conditions free fatty acids are the only lipids labeled, a factor which simplifies the assay. The addition of glycerol to the buffer causes all of the nonesterified fatty acids to be incorporated into glycerolipid. The cells excrete much of the lipid whether glycerol is present or not. Addition of penicillin to the nongrowth supporting buffer system does not stimulate the incorporation of [¹⁴C]-acetate into fatty acids. However, if cells are exposed to penicillin in a growth-supporting medium and then are transferred to the nongrowing buffer system containing no penicillin, the previously exposed cells retain the ability to incorporate [¹⁴C]-acetate into fatty acid at a higher rate than untreated cells over a prolonged period of time. The stimulation of [¹⁴C]-acetate into fatty acids in this system parallels but is not dependent on the stimulation by penicillin of the incorporation of [¹⁴C]-glycerol into glycerolipid and lipoteichoic acid synthesis previously demonstrated by our laboratory. The material of this paper is part of a thesis to be submitted by J.L.B. in partial fulfillment of the requirements for the Ph.D. degree from the Department of Biochemistry, Temple University.     

Induction of favism-like symptoms in the rat: Effects of vicine and divicine in normal and buthionine sulphoximine-treated rats

Rats were fed an adequate or a deficient diet and offered water or buthionine sulphoximine (BSO) solution for 2 weeks, and then the same diets with vicine for another week in experiment 1. BSO in combination with the deficient diet caused a marked decrease in blood glutathione (GSH) and growth retardation but failed to show any effects resulting from supplementation with vicine. In experiment 2 the rats were given an adequate diet and BSO as before, and injected intravenously with divicine (DV). Here again, BSO depressed rat growth, and so did DV. Each of the insults also caused haematological changes, especially a fall in GSH, but the most severe changes appeared in the group treated with both BSO and DV. A decrease in haematocrit and increases in adrenal and spleen weight were also noted. In experiment 3 the rats were injected with different doses of DV, without pretreatment with BSO. The main effect was a drop in blood GSH and haematocrit, and an increase in adrenal and spleen weights, all of which were dose-related. Administration of the higher doses of DV resulted in a severe cyanosis followed by death within a relatively short period of time.     

Aging and memory for words and action events: Effects of item repetition and list length.

We were concerned with the effects of item repetition, list length, and class of item on free recall in elderly as compared with young adults. In Experiment 1, samples of young and elderly adults recalled a list of 27 words and a list of 27 action events (minitasks performed by the subjects). Some items were presented once and some twice. Although the younger subjects showed better recall on both types of lists, the older sample benefited from item repetition as much as did the younger sample. This finding was replicated in Experiment 2. A second finding in Experiment 2 was a significant aging effect in the recall of long but not of short lists of both words and action events. The absence of an Age?×?Repetition Effect interaction was ascribed to the strength nature of the repetition manipulation. The age effects in the recall of the long lists were attributed to possible deficits in retrieval proficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)