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African American adolescents’ career development has gained increased attention in light of various barriers affecting their educational and career development goals. The author examined relationships among career decision self-efficacy, ethnic identity, and academic self-concept of 104 African American high school students enrolled in Upward Bound programs. Participants responded to measures of career decision self-efficacy, ethnic identity, and academic self-concept. Results indicated that career decision self-efficacy was significantly and positively correlated with ethnic identity and academic self-concept. In addition, academic self-concept was found to be a stronger predictor of career decision self-efficacy than was ethnic identity. The results of this study may assist counselors, teachers, administrators, and parents to understand career decision self-efficacy as it relates to ethnic identity, academic self-concept, and demographic variables. This research supports the need for continued career-related interventions within the schools designed to focus on factors related to ethnic minorities to help foster their career development.

Alternaria dauci and Cercospora carotae cause foliar blight on carrot and can reduce yield in severely blighted fields. Historically, fungicides are applied every 7 to 14 days even though applications may be made when environmental conditions do not favor blight development. The purpose of this study was to compare a calendar-based application schedule with three disease forecasting systems for timing fungicide sprays to limit foliar blight, and included (i) an A. dauci disease forecaster, (ii) TOM-CAST, using a threshold of 15 disease severity values, and (iii) a disease forecaster developed to control C. apii on celery. Chlorothalonil was applied weekly or according to the forecasting systems to blight-susceptible ‘Cellobunch’ carrot plants in 2001 and 2002. Overall petiole health was poor ≥8.3; 10 = 100% petiole necrosis) when fungicides were not used. Although all disease forecasters maintained petiole health (≤5.3; 1 = healthy and vigorous), the TOM-CAST program had the best petiole health rating each year (≤2.8). TOM-CAST prompted 38 to 54% fewer applications than the weekly application schedule, resulting in a fungicide savings of $105 and $147/ha in 2001 and 2002, respectively, while providing similar blight control. The number of sprays also was reduced when fungicides were applied according to the A. dauci and C. apii forecasters, but acceptable blight control was not always achieved.

Cercospora carotae and Alternaria dauci cause foliar blight on carrot (Daucus carota subsp. sativus) and are managed with fungicides to prevent yield loss. Sprays are initiated prior to disease symptoms and reapplied frequently, but some of these applications may not be necessary when the threat of disease is low. Delaying the initial fungicide spray until disease symptoms are observed and applying subsequent sprays according to the TOM-CAST disease forecaster may reduce fungicide inputs. The objective of this 2-year field study was to compare preventive, calendar-based application schedules with an integrated management approach that incorporates disease scouting to initiate fungicide application and the TOM-CAST system for timing subsequent fungicide sprays to manage foliar blight on processing, fresh market, and cut-and-peel carrot cultivars in Michigan. Applications of the fungicides chlorothalonil alternated with azoxystrobin were made prior to disease symptoms (0% blight) or when the foliage became blighted at a trace, 5%, or 10% severity level. Fungicides were reapplied every 7 or 10 days or according to TOM-CAST using disease severity value (DSV) thresholds of 15, 20, or 25. Initiating fungicide treatment at a trace level of disease and timing subsequent sprays according to the TOM-CAST 15-DSV forecaster was comparable to the preventive, calendar-based fungicide regime. One to five fewer applications were needed, while fungicide costs were reduced by $21 to $141 per hectare, when spraying at the trace disease threshold and reapplying according to the TOM-CAST 15-DSV program compared with the 7- or 10-day intervals initiated at 0% blight. Fungicide programs initiated at 5 or 10% leaf blight often provided less control than programs initiated at 0% and trace disease. This study highlights the importance of initiating a fungicide program prior to advanced foliar blight and validates the TOM-CAST 15-DSV forecaster for managing Cercospora leaf spot and Alternaria leaf blight in three carrot production systems.

Late blight, incited by the fungus Septoria apiicola, is the most important foliar disease of celery in Michigan and results in necrotic lesions on leaves and petioles that can reduce yield up to 80%. Most celery growers apply the fungicide chlorothalonil as frequently as every 7 days to protect the crop; however, some of these applications may not be needed when environmental conditions do not favor disease development. The purpose of this study was to evaluate disease predictors using a standard (chlorothalonil) and a reduced-risk (azoxystrobin alternated with chlorothalonil) fungicide program for managing late blight on ‘Dutchess’ celery in 2003 to 2005. Fungicides were initiated 1 week after transplanting and reapplied every 7 days or according to the Septoria, Cercospora, or TOM-CAST predictors. The TOM-CAST predictor was tested using 10, 15, and 20 disease severity values (DSV) as thresholds for fungicide application. In each year of this study, timing sprays according to the TOM-CAST 10-DSV predictor resulted in disease control comparable with the 7-day interval, but required up to five fewer sprays and reduced fungicide costs up to $215/ha. The Septoria, Cercospora, and TOM-CAST 15-DSV predictors often provided control similar to the 7-day interval, but these predictors were somewhat inconsistent compared with TOM-CAST 10-DSV. The TOM-CAST 20-DSV predictor required the fewest number of sprays but unacceptable levels of disease resulted. The standard and reduced-risk fungicide programs frequently provided similar control; however, azoxystrobin alternated with chlorothalonil was more effective than chlorothalonil alone when disease pressure was high.

Late blight of celery, incited by Septoria apiicola, results in necrotic lesions on leaves and petioles and reduces yield when it occurs on marketable petioles. Michigan celery growers typically begin applying fungicides 1 to 3 weeks after transplanting and reapply fungicides at 7- to 10-day intervals to manage late blight. Using disease thresholds or predictors to prompt fungicide sprays may reduce the number of applications needed for effective disease control. Weekly treatments of azoxystrobin alternated with chlorothalonil were initiated early (1 week after transplanting), preventively (4 weeks after transplanting), or when disease symptoms were detected at a trace, 5%, or 10% level on ‘Dutchess’ celery plants in 2003 and 2004. The early and preventive programs were equally effective in preventing petiole blight and yield loss. The preventive program required three fewer applications, at a savings of up to $134/ha, when compared with an early fungicide program initiated 1 week after transplanting. Delaying the initial fungicide application until disease symptoms were detected resulted in high disease levels at harvest that were often similar to untreated control plants. Additional field trials were established in 2004 and 2005 at a research farm where S. apiicola inoculum was applied and at a commercial field where early blight, caused by Cercospora apii, developed from naturally occurring inoculum. A fungicide program that alternated chlorothalonil with azoxystrobin was initiated preventively and reapplied weekly or according to the Septoria predictor or TOM-CAST 10-disease severity value (DSV) and was compared with the standard, weekly application program initiated early. Combining the use of preventive initial applications with the Septoria predictor or TOM-CAST 10-DSV reduced the number of sprays by two to six while providing disease control that was comparable with the standard weekly fungicide program initiated early. These programs reduced fungicide expenditures by $71 to $213/ha compared with the weekly fungicide program initiated early.

Objective Osteoarthritis (OA), a chronic degenerative joint disorder, is characterized by joint pain. Emerging research demonstrates that a significant number of patients evidence central sensitization (CS), a hyperexcitability in nociceptive pathways, which is known to amplify and maintain clinical pain. The clinical correlates of CS in OA, however, are poorly understood. Insomnia is prevalent in older adults with OA, and recent experiments suggest associations between poor sleep and measures of CS. Catastrophizing, a potent predictor of pain outcomes, has also been associated with CS, but few studies have investigated possible interactions between catastrophizing, sleep, and CS. Methods We conducted a case–control study of 4 well-characterized groups of adults with insomnia and/or knee OA. A total of 208 participants completed multimodal sleep assessments (questionnaire, diary, actigraphy, and polysomnography) and extensive evaluation of pain using clinical measures and quantitative sensory testing to evaluate associations between CS, catastrophizing, and insomnia. Descriptive characterization of each measure is presented, with specific focus on sleep efficiency and CS. Results The knee OA–insomnia group demonstrated the greatest degree of CS compared to controls. In the overall sample, we found that catastrophizing moderated the relationship between sleep efficiency and CS. Specifically those with low sleep efficiency and high catastrophizing scores reported increased levels of CS. In addition, CS was significantly associated with increased clinical pain. Conclusion These findings highlight the importance of assessing sleep efficiency, CS, and catastrophizing in chronic pain patients and have important clinical implications for treatment planning.

Objective Although poor sleep is a consequence of pain, sleep disturbance reciprocally induces hyperalgesia and exacerbates clinical pain. Conceptual models of chronic pain implicate dysfunctional supraspinal pain processing mechanisms, mediated in part by endogenous opioid peptides. Our preliminary work indicates that sleep disruption impairs psychophysical measures of descending pain modulation, but few studies have investigated whether insufficient sleep may be associated with alterations in endogenous opioid systems. This preliminary, exploratory investigation sought to examine the relationship between sleep and functioning of the cerebral mu opioid system during the experience of pain in healthy participants. Subjects and Design Twelve healthy volunteers participated in a 90-minute positron emission tomography imaging scan using [11C]Carfentanil, a mu opioid receptors agonist. During the session, pain responses to a 10% topical capsaicin cream were continuously rated on a 0–100 scale. Participants also completed the Pittsburgh Sleep Quality Index (PSQI). Results Poor sleep quality (PSQI) was positively and significantly associated with greater binding potential (BP) in regions within the frontal lobes. In addition, sleep duration was negatively associated with BP in these areas as well as the temporal lobe and anterior cingulate. Conclusions These findings suggest that poor sleep quality and short sleep duration are associated with endogenous opioid activity in these brain regions during the application of a noxious stimulus. Elucidating the role of the endogenous opioid system in mediating some of the associations between sleep and pain could significantly improve our understanding of the pathophysiology of chronic pain and might advance clinical practice by suggesting interventions that could buffer the adverse effects of poor sleep on pain.

SummaryHuman cytomegalovirus (CMV) infection is normally controlled effectively by the immune response, including CD4+ T cells. Large numbers of these cells are present in healthy seropositive individuals but their loss in immunosuppression leads to reactivation and disease. Tracking such responses in vivo is hampered by poor definition of their peptide targets. In this study, we defined the key targets of the peptide-specific CD4+ T cell responses to the CMV pp65 protein using functional assays and a peptide library. Despite a good deal of interindividual variation in the numbers of peptides recognized, responses to CMV pp65 were strikingly targeted at three key epitopes. A response to one or more of these three key peptides was seen in all individuals tested (P

Manipulated anger suppression has been shown to heighten pain and anger responses to pain. We examined whether individual differences in self-reported anger suppression predicted pain, anger, and blood pressure responses to acute pain. Healthy participants (N = 47) underwent an anger-provoking speech task followed by a cold pressor pain task. Participants reported their degree of suppression of thoughts and feelings related to the speech. Pain intensity ratings were obtained throughout the cold pressor. Self-reported anger, anxiety and positive emotion, as well as ratings of sensory, general distress, and anger-specific elements of pain were obtained following the cold pressor. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were recorded throughout. Self-reported suppression predicted greater pain intensity ratings, perception of sensory and anger-specific elements of pain, and self-reported anger in response to the cold pressor. Associations between self-reported suppression and pain intensity and ratings of anger-specific elements of pain were statistically mediated by pain-induced changes in self-reported anger, whereas the effect of suppression on sensory pain ratings was not. Self-reported suppression was also correlated inversely with SBP responses to the cold pressor. Consistent with an ironic process model and prior studies involving experimental manipulation of suppression, self-reported suppression of anger predicted greater pain intensity and perception of the anger-specific element of pain. Findings also suggest that suppression might attenuate homeostatic pressor responses to acute pain.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder associated with a premutation trinucleotide repeat expansion in the fragile X mental retardation 1 gene (FMR1). Symptoms include gait ataxia, action tremor, and cognitive impairment. The objectives of the study were to clarify the nature of the dysexecutive syndrome observed in FXTAS and to assess the contribution of executive impairment to deficits in nonexecutive cognitive functions. Compared to controls, men with FXTAS demonstrated significant executive impairment, which was found to mediate group differences in most other cognitive abilities. Asymptomatic premutation carriers performed similarly to controls on all but two measures of executive functioning. These findings suggest that the impairment of non-executive cognitive skills in FXTAS is in large part secondary to executive dysfunction.

The Army has many rigid-body dynamic models of various vehicle platforms. The adequacy of these rigid-body models has been questioned. In an effort to gain insight into the significance of flexibility in the development of dynamic vehicle models, operating deflection shape (ODS) techniques were applied to acceleration data gathered from the body of a wheeled military vehicle. The data were analyzed in an effort to determine a specific frequency range over which the assumption of rigidity would be valid. For the particular platform examined in this study, the assumption of rigidity would apply up to approximately 14 Hz. Future efforts include using operational modal analysis (OMA) to further examine the problem.

The objective of the Active Plasma Experiment North Star mission was to study the interaction of artificially produced aluminum ion plasma jets with the space environment. Two separate plasma jets were injected almost perpendicular to the local magnetic field during the North Star experiment. The jets were created using an explosivetype generator designed to produce a high-speed (7‐42-km/s) aluminum ion plasma jet with plasma densities exceeding 10 9 cm −3 at a distance 170 m from the plasma-jet source. The first plasma-jet injection occurred at an altitude of 360 km and was preceded by the release of an artificial air cloud. The second injection occurred at an altitude of 280 km and did not include the air cloud. Interactions of the plasma jet with the local space environment and artificial air cloud were monitored using instrumentation on three diagnostic payloads, ground-based optical sensors, and space-based optical sensors. An overview is provided of the experiment, along with a summary of the principal results from the mission.

This paper is concerned with the application of a coarse preconditioner, the generalised minimal residual (GMRES) method and a generalised successive over-relaxation (GSOR) method to linear systems of equations that are derived from boundary integral equations. Attention is restricted to systems of the form ∑ N j =1 H ij x j = c i , i =1,2,…, N , where H ij are matrices, x j and c i are column vectors. The integer N denotes the number of domains and these systems are solved by adapting techniques initially devised for solving single-domain problems. These techniques include parameter matrix accelerated GMRES and GSOR in combination with a multiplicative Schwarz method for non-overlapping domains. The multiplicative Schwarz method is a generalised form of the block Gauss–Seidel method and is called the generalised multi-domain iterative procedure. A new form of coarse grid preconditioning is applied to limit the convergence dependence on block numbers. The coarse preconditioner is obtained from a crude representation of the global system of equations. Attention is restricted to thermal problems with domains connected through resistive thermal barriers. The effect of lowering and increasing the thermal resistance between domains is investigated. The coarse preconditioner requires a more accurate representation on interfaces with lower thermal resistance. Computation times are determined for the iterative procedures and for elimination techniques indicating the relative benefits for problems of this nature.

Aberrant circadian rest/activity rhythms (RARs) may promote poor aging-related health outcomes. Osteoarthritis and chronic insomnia are common age-related conditions, but the circadian RARs of each group have not been well characterized or compared. We evaluated actigraphic RARs in individuals with: (1) knee osteoarthritis (KOA) only; (2) chronic insomnia only; (3) KOA + insomnia; and (4) pain-free good sleepers. Compared to participants with KOA only, those with KOA + insomnia had less robust RARs. There were no differences between other groups. Further research is needed to evaluate whether aberrant RARs contribute to arthritis symptoms and insomnia in KOA, and whether strengthening RARs ameliorates arthritis symptoms.

High-integrity castings require sophisticated design and manufacturing procedures to ensure they are essentially macrodefect free. Unfortunately, an important class of such defects—macroporosity, misruns, and pipe shrinkage—are all functions of the interactions of free surface flow, heat transfer, and solidication in complex geometries. Because these defects arise as an interaction of the preceding continuum phenomena, genuinely predictive models of these defects must represent these interactions explicitly. This work describes an attempt to model the formation of macrodefects explicitly as a function of the interacting continuum phenomena in arbitrarily complex three-dimensional geometries. The computational approach exploits a compatible set of finite volume procedures extended to unstructured meshes. The implementation of the model is described together with its testing and a measure of validation. The model demonstrates the potential to predict reliably shrinkage macroporosity, misruns, and pipe shrinkage directly as a result of interactions among free-surface fluid flow, heat transfer, and solidification.

In this paper an iterative scheme of first degree is developed for the purpose of solving linear systems of boundary element equations of the form $Hx = c$ where $H$ is a dense square nonsingular matrix. The iterative scheme considered is $$ (D + (\Omega H)_{sl})x^{(k + 1)} = (D - (\Omega H)_{u})x^{(k)} + \Omega c, $$ \noindent where $(\Omega H)_u$ and $(\Omega H)_{s1}$ are defined as the upper triangular and strictly lower triangular terms of $\Omega H$, respectively. The parameter matrix $\Omega$ is selected to minimize the Frobenius norm $\|D - (\Omega H)_u\|_F$. Mathematical arguments and numerical experiments are presented to show that minimizing $\|D - (\Omega H)_u\|_F$ provides for faster convergence. Numerical tests are performed for systems of boundary element equations generated by three-dimensional potential and elastostatic problems. Computation times are determined and compared against those for Gaussian elimination and Gauss--Seidel iteration.

In this paper a novel preconditioning strategy is presented that is designed to improve the convergence rates of the Generalized Minimal Residual (GMRES) method when applied to dense linear systems of boundary element equations of the form Hx = c. The GMRES method is applied to the preconditioned system (D+ L ) −1 ΩHx = (D+ L ) −1 Ωc , where D = diag(H), L is the strictly lower triangular part of ΩH and Ω is a sparsely populated upper triangular matrix. The coefficients in Ω are determined via the minimization of the square of the Frobenius norm map; U + D −Dmap; F , where U is the strictly upper triangular part of ΩH and D = diag (ΩH) . Several proofs are given to demonstrate that minimizing map; U + D −Dmap; F 2 provides for improved conditioning and consequently faster convergence rates. Numerical experiments are performed on systems of boundary element equations generated by three-dimensional potential and elastostatic problems. Computation times are determined and compared against those for Jacobi preconditioned GMRES, preconditioned Gauss-Seidel and Gaussian elimination. Moreover, condition numbers are noted and up to 100-fold reductions are observed for the systems tested.

This paper is concerned with an investigation into the benefits and problems of modelling the pressure die casting process using a finite element solidification model for the casting and boundary element model for the die. Linking boundary and finite element methods is beset with difficulties with each method requiring different mesh, time-step and other requirements for accurate results. The numerical models described in this paper have been specifically developed to overcome these problems. In particular, novel finite element solidification and transient thermal boundary element formulations have been developed. Moreover, iterative solution procedures have been formulated and implemented to enable the efficient solution of the coupled systems of non-linear equations. The latent energy released during solidification is calculated using a swept volume formulation which has shown itself to be highly stable and accurate, even for relatively course meshes and large time-steps. The domain integrals generated by the boundary element method have been avoided by developing a source based approximation procedure. The iterative schemes developed for solving the systems of equations are based on new and classical methods. The use of iterative schemes allows the boundary and finite element meshes and time-steps to be decoupled so that accuracy can be maintained. This decoupling is required because although the new solidification formulation allows for relatively course meshes and time-steps it is still unable to compete with the boundary element method in this regard. The predictions made by the model are compared against experimental results to demonstrate the accuracy of this approach.

Radiographic measures of the pathologic changes of knee osteoarthritis (OA) have shown modest associations with clinical pain. We sought to evaluate possible differences in quantitative sensory testing (QST) results and psychosocial distress profiles between knee OA patients with discordant versus congruent clinical pain reports relative to radiographic severity measures.A total of 113 participants (66.7% women; mean ± SD age 61.05 ± 8.93 years) with knee OA participated in the study. Radiographic evidence of joint pathology was graded according to the Kellgren/Lawrence scale. Central sensitization was indexed through quantitative sensory testing, including heat and pressure-pain thresholds, tonic suprathreshold pain (cold pressor test), and repeated phasic suprathreshold mechanical and thermal pain. Subgroups were constructed by dichotomizing clinical knee pain scores (median split) and knee OA grade scores (grades 1-2 versus 3-4), resulting in 4 groups: low pain/low knee OA grade (n = 24), high pain/high knee OA grade (n = 32), low pain/high knee OA grade (n = 27), and high pain/low knee OA grade (n = 30).Multivariate analyses revealed significantly heightened pain sensitivity in the high pain/low knee OA grade group, while the low pain/high knee OA grade group was less pain-sensitive. Group differences remained significant after adjusting for differences on psychosocial measures, as well as age, sex, and race.The results suggest that central sensitization in knee OA is especially apparent among patients with reports of high levels of clinical pain in the absence of moderate-to-severe radiographic evidence of pathologic changes of knee OA.

Although sleep deprivation is known to heighten pain sensitivity, the mechanisms by which sleep modifies nociception are largely unknown. Few studies of sleep-pain interactions have utilized quantitative sensory testing models that implicate specific underlying physiologic mechanisms. One possibility, which is beginning to receive attention, is that differences in sleep may alter the analgesic effects of distraction. We utilized the heat-capsaicin nociceptive model to examine whether self-reported habitual sleep duration is associated with distraction analgesia, the degree of secondary hyperalgesia and skin flare, markers implicating both central and peripheral processes that heighten pain. Twenty-eight healthy participants completed three experimental sessions in a randomized within subjects design. In the pain only condition, pain was induced for approximately 70-minutes via application of heat and capsaicin to the dorsum of the non-dominant hand. Verbal pain ratings were obtained at regular intervals. In the distraction condition, identical procedures were followed, but during heat-capsaicin pain, subjects played a series of video games. The third session involved assessing performance on the video games (no capsaicin). Participants indicated their normal self-reported habitual sleep duration over the past month. Individuals who slept less than 6.5 hours/night in the month prior to the study experienced significantly less behavioral analgesia, increased skin flare and augmented secondary hyperalgesia. These findings suggest that reduced sleep time is associated with diminished analgesic benefits from distraction and/or individuals obtaining less sleep have a reduced ability to disengage from pain-related sensations. The secondary hyperalgesia finding may implicate central involvement, whereas enhanced skin flare response suggests that sleep duration may also impact peripheral inflammatory mechanisms.

Background Fragile X-associated tremor/ataxia syndrome (FXTAS), which occurs in some premutation carriers of the fragile X mental retardation 1 (FMR1) gene, is a neurodegenerative disorder characterized by action tremor, gait ataxia, and impaired executive cognitive functioning. Objective To evaluate the nature and severity of functional limitations among male carriers of the fragile X premutation, both with and without FXTAS. Methods Forty-two subjects with FXTAS and 24 asymptomatic premutation carriers were compared to 32 control subjects on measures of physical functioning, activities of daily living (ADLs; e.g. eating, bathing), and instrumental activities of daily living (IADLs; e.g. shopping, managing medications). Ordinary least squares regression, controlling for age, education, medical comorbidity, and pain, was used to examine group differences in physical and functional performance. Results Men with FXTAS performed significantly worse than control subjects on all dependent measures, showing greater limitations in physical functioning, as well as ADL and IADL performance (p

The performance of military ground vehicle systems quickly degrades due to high operation tempo and extreme environments while performing in-theater service. Current maintenance methods associated with this degradation are not sufficiently optimized for cost and performance. To address this issue, the United States Army is implementing a policy of Condition Based Maintenance (CBM) and being supported by the Army Materiel System Analysis Activity (AMSAA). CBM is a plan of maintenance for a system based upon the actual condition of the system as enabled by the application of usage, diagnostic and prognostic processes executed on a Health and Usage Monitoring System (HUMS). AMSAA has developed and is implementing a CBM system for ground vehicles. This development process has included the development of a robust military-grade HUMS in conjunction with the Aberdeen Test Center and the development of data collection, reduction, analysis, and reporting processes. A key requirement underlying these processes is a thorough understanding of both the ways in which system condition is degenerated and the ability of the HUMS to detect, identify, and communicate all conditions that requires maintenance in a timely manner. AMSAA and the US Army Aberdeen Test Center (ATC) have jointly initiated testing and applications as the critical means of filling this requirement.

Fragile X-associated tremor/ataxia syndrome (FXTAS) develops in a subset of fragile X premutation carriers and involves gait ataxia, action tremor, Parkinsonism, peripheral neuropathy, autonomic disorders, and cognitive impairment. The study was designed to define the nature of cognitive deficits affecting male premutation carriers with and without FXTAS. A sample of 109 men underwent motor, cognitive, genetic, and neurologic testing, as well as brain magnetic resonance imaging. Subjects were classified into 3 groups: (a) asymptomatic premutation carriers, (b) premutation carriers with FXTAS, and (c) normal controls. Men with FXTAS performed worse than controls on mental status, intelligence, executive cognitive functioning (ECF), working memory, remote recall of information, declarative learning and memory, information processing speed, and temporal sequencing, as well as 1 measure of visuospatial functioning. Language and verbal comprehension were spared. Asymptomatic carriers performed worse than controls on ECF and declarative learning and memory. This comprehensive examination of cognitive impairment in male premutation carriers suggests that FXTAS involves substantial executive impairment and diffuse deficits in other cognitive functions. Longitudinal research currently underway will provide insight into the progression of the disorder.

Performance testing is an important step in the development of any vehicle model. Generally, full-scale field tests are conducted to collect the dynamic response characteristics for evaluating the vehicle performance. However, with increases in computational power and the accuracy of simulation models, virtual testing can be extensively used as an alternative to the time consuming and costly full-scale tests, especially for severe maneuvers. Validation of the simulation results is critical for the acceptance of such simulation models. In this paper, a methodology for validating the vertical dynamic performance of a virtual vehicle has been discussed. The dynamic performance of a multi-wheeled combat vehicle model specially developed using a multi-body dynamics code was validated against the measured data obtained on the U.S. Army Aberdeen Test Center’s (ATC) test courses. The multi-wheeled combat vehicle variant computer simulation model was developed in TruckSim, a vehicle dynamic simulation software developed by the Mechanical Simulation Corporation. Prior to validating the model, the vehicle weights, dimensions, tires and suspension characteristics were measured and referenced in the specially developed computer simulation model. The data for the tire and suspension characteristics were acquired from the respective leading manufacturers in the form of look-up tables. The predictions of the vehicle vertical dynamics on different road profiles at various vehicle speeds were compared with the field test results. The time domain data for the vertical acceleration at the vehicle center of gravity, pitching, vehicle speed and the suspension/damper displacement were compared to analyze the feasibility of using the computer simulation models to predict the vertical dynamic performance of the vehicle. Based on the results it was found that the particular combat vehicle computer simulation model is capable of predicting the vertical dynamic performance characteristics.Copyright © 2005 by ASME

An overview of the design and implementation of a software environment for the computational modelling of engineering processes is described, where the coupling amongst phenomena is strong. It is asserted that such a framework is necessary because of the numerical consistency and minimal data exchange required to enable such multi-physics calculations to be made effectively and in a practical time frame. The data exchange issue is further exacerbated by the need to exploit parallel high performance systems to generate simulation results in hours rather than weeks of elapsed time. The object based software framework uses 3D finite volume techniques on an unstructured mesh that facilitates free surface flows, heat transfer with phase change and non-linear solid mechanics. High parallel efficiencies are demonstrated and applications of the software framework to a range of problems with various degrees of coupling amongst the physical phenomena are highlighted. Particularly, in the context of shape casting, it is demonstrated how that simulation of the interactions is necessary to predict the defects of key interest to the target manufacturing sectors.

Introduction Fibromyalgia (FM), characterized by wide-spread diffuse pain and sensory abnormalities, is associated with elevated indices of distress and pain-related catastrophizing compared to both pain-free samples and those with chronic pain conditions. Catastrophizing is a pervasive negative mental set, and is a strong predictor of negative pain-related outcomes such as clinical pain intensity, and physical disability. Situational catastrophizing, measured in the context of experimentally-induced pain, is strongly related to enhanced pain sensitivity, a core aspect of the pathophysiology of fibromyalgia. However, little is known regarding the temporal course of the association between catastrophizing and pain-related "outcomes". Most studies involve only static assessments of pain and catastrophizing at a single time point, which provides little insight into the direction of the observed associations. We sought to investigate the temporal relationships between catastrophizing and indices of both clinical pain (substudy 1) and experimentally-induced pain (substudy 2) in a larger randomized controlled longitudinal trial. Methods Fifty-seven patients with FM completed catastrophizing, depression, and pain questionnaires as well as laboratory cold pressor pain testing at baseline, post-intervention and three month follow-up during a lifestyle physical activity study. Cross-lagged panel analyses were used to address these temporal relationships. Results In substudy 1, analyses revealed that pre-to-post changes in dispositional catastrophizing ratings prospectively accounted for unique variance in subsequent post-to-follow-up changes in clinical pain ratings (p = 0.005), while pre-to-post changes in pain ratings did not account for unique variance in post-to-follow-up changes in catastrophizing ratings. An identical pattern was observed experimentally in substudy 2, with pre-to-post changes in situational catastrophizing ratings prospectively accounting for unique variance in subsequent post-to-follow-up changes in experimental pain ratings (p = 0.014), while pre-to-post changes in pain ratings did not account for unique variance in post-to-follow-up changes in catastrophizing ratings. Specifically, initial alterations in catastrophizing were associated with subsequent alterations in clinical and experimentally induced pain. Controlling for levels of depression did not affect the results. Conclusions These findings provide empirical evidence that catastrophizing processes might precede and contribute to subsequent alterations in the pain experience for FM patients. Trial Registration clinicaltrials.gov: NCT00383084.