Influence of a patient decision aid on decisional conflict related to PSA testing: A structural equation model.

Objective: To examine the impact of a decision aid (DA) designed to promote informed decision making for screening with the prostate-specific antigen (PSA) test and to test a theoretical model of factors influencing decisional conflict. Design: Structural equation modeling examined pathways between DA exposure, knowledge, schema, prostate cancer risk perceptions, decisional anxiety, and decisional conflict. Sample participants included 200 men from the general population (exclusive of African Americans) and 200 African American men. Half of the men in each subsample were randomly assigned to receive the DA. Main Outcome Measures: Decisional conflict regarding prostate cancer screening. Results: The DA influences level of decisional conflict by increasing patient knowledge. This effect of knowledge on decisional conflict is indirect, however, through an association with greater perceived risk and lower decisional anxiety. Also, positive PSA schema was associated with lower decisional anxiety and decisional conflict. It is important that exposure to the DA had no impact on PSA schema. Conclusion: Schemas about testing must be considered in developing messages about the risks and benefits of testing. If schemas are counter to message content, mechanisms for modifying schemas must be incorporated into interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Online Fault Tolerance for FPGA Logic Blocks

Most adaptive computing systems use reconfigurable hardware in the form of field programmable gate arrays (FPGAs). For these systems to be fielded in harsh environments where high reliability and availability are a must, the applications running on the FPGAs must tolerate hardware faults that may occur during the lifetime of the system. In this paper, we present new fault-tolerant techniques for FPGA logic blocks, developed as part of the roving self-test areas (STARs) approach to online testing, diagnosis, and reconfiguration . Our techniques can handle large numbers of faults (we show tolerance of over 100 logic faults via actual implementation on an FPGA consisting of a 20 times 20 array of logic blocks). A key novel feature is the reuse of defective logic blocks to increase the number of effective spares and extend the mission life. To increase fault tolerance, we not only use nonfaulty parts of defective or partially faulty logic blocks, but we also use faulty parts of defective logic blocks in nonfaulty modes. By using and reusing faulty resources, our multilevel approach extends the number of tolerable faults beyond the number of currently available spare logic resources. Unlike many column, row, or tile-based methods, our multilevel approach can tolerate not only faults that are evenly distributed over the logic area, but also clusters of faults in the same local area. Furthermore, system operation is not interrupted for fault diagnosis or for computing fault-bypassing configurations. Our fault tolerance techniques have been implemented using ORCA 2C series FPGAs which feature incremental dynamic runtime reconfiguration     

Agreement of skinfold measurement and bioelectrical impedance analysis (BIA) methods with dual energy X-ray absorptiometry (DEXA) in estimating total body fat in Anglo-Celtic Australians

OBJECTIVE: To compare percentage total body fat (%BF) estimated by the four skinfold thickness measurement (SKF) and single-frequency bioelectrical impedance analysis (BIA) methods using three different sets of equations, to that assessed by the dual energy X-ray absorptiometric (DEXA) method using a Lunar DPX densitometer. DESIGN: Cross-sectional study. SUBJECTS: An Anglo-Celtic Australian population of 66 males and 130 females (age: 26-86 y). MEASUREMENTS: %BF by anthropometry, BIA using three different sets of equations and DEXA. RESULTS: Mean %BF assessed by DEXA (%BF(DEXA)) was similar to that estimated by SKF (%BF(SKF)) in males, while %BF(DEXA) was slightly higher in females. %BF estimated by BIA (%BF(BIA)) was significantly lower than %BF(DEXA) in females, regardless of equations used for calculation, while the level of agreement between BIA and DEXA in estimating %BF in males was dependent on prediction equations used for calculation of %BF(BIA). A better agreement was obtained from the use on the prediction equations of Segal et al (1988), compared to other two sets of equations. The agreement between SKF or BIA and DEXA declined with increasing %BF. CONCLUSIONS: There was a good agreement between DEXA and SKF, and slightly less so between DEXA and BIA, in estimating %BF in an Anglo-Celtic adult population. The agreement in most cases, however, was dependent on the degree of body fatness. In comparison to DEXA, both SKF and BIA, with the use of the equations of Segal et al (1988), are applicable to estimate %BF in an Anglo-Celtic Australian population.     

Posttraumatic stress disorder and late-onset smoking in the Vietnam era twin registry.

Epidemiological and clinical studies have consistently reported associations between smoking and posttraumatic stress disorder (PTSD). This study analyzed diagnostic interview data on 6,744 members of the Vietnam Era Twin Registry to clarify the PTSD-smoking relation and to examine whether genetic liability for smoking moderated this relation. Preexisting active (unremitted) PTSD increased risk of late-onset daily smoking. Remitted PTSD decreased risk. Active PTSD increased risk of smoking at all levels of genetic liability; the effect was strongest for those with least genetic liability. This suggests PTSD represents a nongenetic pathway to late-onset smoking among individuals who were nonsmokers prior to developing PTSD. If replicated, these results identify PTSD as a risk factor for smoking that should lead to early tobacco control treatment in this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Automatic linearity and frequency response tests with built-in pattern generator and analyzer

We present a built-in self-test (BIST) approach based on a direct digital synthesizer (DDS) for functionality testing of analog circuitry in mixed-signal systems. A main contribution of this paper is the BIST-based hardware implementation and measurement of amplifier linearity (IP3) and frequency response, including both phase and gain. The approach has been implemented in Verilog and synthesized into a field-programmable gate array (FPGA), where it was used for functional testing of an actual device under test (DUT) and compared to simulation results.     

Dewey's integrated logic of science, ethics, and practice.

H. H. Kendler (see record 1994-09190-001), in his article on psychology and the ethics of social policy, argues in part that ethical imperatives cannot be inferred from empirical data. J. Dewey's (1929 [1958], 1938) instrumentalism and logic of inquiry are presented as solutions to the trifurcation of theoretical science, ethics, and practical science. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Learning and adaptation in an airborne laser fire controller

A simulated battlefield, containing airborne lasers that shoot ballistic missiles down, provides an excellent test-bed for developing adaptive controllers. An airborne laser fire controller, which can adapt the strategy it uses for target selection, is developed. The approach is to transform a knowledge-based controller into an adaptable connectionist representation, use supervised training to initialize the weights so that the adaptable controller mimics the knowledge-based controller, and then use directed search with simulation-based performance evaluation to continuously adapt the controller behavior to the dynamic environmental conditions. New knowledge can be directly extracted from the automatically discovered controllers. Three directed search methods are characterized for production training, and compared with the better characterized gradient descent methods commonly used for supervised training. Automated discovery of improved controllers is demonstrated, as is automated adaptation of controller behavior to changes in environmental conditions.