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• A unified gross traction algorithm is proposed for braked, towed, and powered wheels on clay. • The model is developed using the Database Records for Off-road Vehicle Environments. • The algorithm employs the ratio of average contact pressure to cone index. • The new equation can be implemented in off-road mobility models. A characteristic curve is presented for predicting gross traction of a wheel over a range of powered, towed, and braked modes on clay soils for slip ranging from positive 100% powered slip to negative 100% skid slip. The characteristic curve is a unified approach that relates the ratio of the contact pressure of the wheel to soil strength and predicts the gross traction coefficient over a continuous range of slip. The unified equation is defined by five inflection points: maximum/minimum traction, traction at zero slip, max change in traction with slip, and a shape factor coefficient. The inflection points aim to simplify the calibration of gross traction, slip, soil strength, and contact pressure by using functions adaptable to machine learning. The unified equation is comparable to historic traction equations but is unique in its ability to predict asymmetric braking and powered gross traction. The unified equation is supported and substantiated via error analysis by utilizing the Database Records for Off-road Vehicle Environments (DROVE) – a database constructed around the archived laboratory and field tests for wheels and tracks operating on different soils. The accuracy of the proposed model is assessed and compared to other conventional equations such as the Brixius equation and Maclaurin's extension of the Pacejka equation for off-road traction. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jebo.2004.09.005 Byline: William A. Darity (a)(b), Patrick L. Mason (c), James B. Stewart (d) Keywords: Economics; Persistence; Racial identity Abstract: This study uses evolutionary game theory to model the relationship between racial identity formation and inter-racial disparities in economic and non-economic outcomes. Starting with a fixed population of persons who are easily identified according to an exogenous criterion, for example, phenotype, we then allow individuals to pursue either a racialist or an individualist identity strategy in social interactions. The formation of identity norms imposes both positive and negative externalities on each person's identity actions. There are forces in the model that might push society toward racialism, individualism, or a mixed identity equilibrium, depending on matching assumptions, dynamic assumptions, parameter values, and initial conditions. Author Affiliation: (a) University of North Carolina, NC, USA (b) Duke University, NC, USA (c) Department of Economics, Florida State University, 246 Bellamy Building, Tallahassee, FL 32308-2180, USA (d) Pennsylvania State University, PA, USA Article History: Received 11 September 2002; Revised 12 March 2004; Accepted 1 September 2004

A model for studying the link between racial identity conditions and inter-racial differences in terms of economic status is presented. Evolutionary game theory is used for construction of the model.

Direct exposure to gender identity-related discrimination and erasure among the transgender and gender independent (TGI) population are associated with healthcare underutilization, which may further exacerbate the health disparities that exist between this population and cisgender individuals in the United States (U.S.). Although the impacts of direct exposure to healthcare discrimination and erasure may have on TGI individuals are known, exposure to such harm vicariously (i.e., through observation or report) is underexplored. The present study examined the relationships among direct and vicarious gender identity-related healthcare discrimination and erasure exposure and past-year healthcare utilization. Gender identity-based mistrust in healthcare was also assessed, as a mechanism through which direct and vicarious gender identity-related healthcare discrimination and erasure predict healthcare utilization behaviors among a sample (N = 385) of TGI adults in the U.S., aged 18 to 71 recruited online. Results indicated direct lifetime and vicarious healthcare discrimination and erasure exposure significantly predicted past-year healthcare underutilization when participants anticipated encountering gender identity-related healthcare discrimination. Mediational analyses indicated that higher levels of exposure to direct lifetime and vicarious healthcare discrimination and erasure were related to higher levels of mistrust in healthcare, through which past-year underutilization was significantly related. These findings are vital to informing healthcare practice and policy initiatives aimed at ensuring the barriers that deleteriously influence the accessibility of healthcare among TGI individuals are ameliorated. • TGI adults reported an average of 3.5 direct, 5 vicarious forms of healthcare discrimination. • TGI adults experience ∼4x more healthcare discrimination than general population. • 29% of TGI adults report avoiding needed healthcare in the prior year. • Medical mistrust is related to direct/vicarious TGI discrimination and erasure. [ABSTRACT FROM AUTHOR]

Background: Prior work suggests some individual immunomarkers may be useful moderators of treatment response between antidepressant medications. The relative moderating effect of individual immunomarkers remains unclear. It is also unknown whether combinations of immunomarkers have a superior moderating effect compared to any individual immunomarker.Methods: Baseline immunomarker levels were assayed using multiplex from a subset of participants in the CO-MED trial (n = 143). Individual and combinations of 19 immunomarkers were modeled as moderators between the three treatment arms (escitalopram monotherapy, escitalopram-bupropion and venlafaxine-mirtazapine) across a variety of depression outcomes.Results: Only IL-13 demonstrated a consistent moderating effect across all depression outcome measures. High IL-13 (>20 pg/ml) was associated with higher remission rates to bupropion-escitalopram (67%) versus escitalopram (24%) whereas low IL-13 was associated higher remission rates to escitalopram (59%) versus bupropion-escitalopram (38%). A similar, but weaker moderating effect was observed with venlafaxine-mirtazapine versus escitalopram. The addition of multiple immunomarkers did not consistently improve predictive modeling.Limitations: This is a secondary analysis of a single clinical trial with a relatively small sample size per treatment arm. The testing of specific individual and combinations of biomarkers was data-driven.Conclusions: Among 19 immunomarkers, Il-13 was the best single moderator of treatment outcome. Combinations of immunomarkers were not meaningfully superior to Il-13. [ABSTRACT FROM AUTHOR]

• Equations exist for the conversion of Cone Index to select Bevameter parameters. • The Cone index correlation relates to the bearing capacity Bevameter parameters Kc, K φ , and n. • Correlations do not exist between cone index and surface shear parameters c, ϕ. • The equations are supported by limited validation in select regional areas of sand and clay. This paper reviews experimental methods for the conversion of cone index measurements to bevameter parameters in support of vehicle soil/tire/track interactions for two general soil types, sand and lean clay. The accurate prediction of traction, motion resistance, and sinkage of tire/tracks off-road requires estimates of soil strength. Equipment used in the measurement of soil strength to support predictions of off-road mobility include the bevameter and the cone penetrometer. The portability of the cone penetrometer and rapid estimates of spatial/temporal variability in all terrain conditions make it an invaluable tool. The bevameter, a less portable tool, is used for the mechanical analysis of soils. The bevameter measures parameters defining soil strength in terms of cohesive modulus of soil deformation (k c), frictional modulus of soil deformation (k φ), exponent of soil sinkage (n), cohesion (c), angle of internal friction (φ), and the plate pressure at 1 in. (2.54 cm) of penetration (K) (Bekker, 1969). The field of terramechanics would greatly benefit from having the ability to convert cone penetrometer data in areas where bevameter parameters are difficult to collect. That ability to convert from cone index to bevameter parameters could be used for the large sets of existing cone index data to support determination of traction and motion resistance. This paper examines those methods for converting cone index to bevameter plate penetration parameters k c , k φ , and n. [ABSTRACT FROM AUTHOR]

Immunosuppression strategies have changed over time in pediatric heart transplantation. Thus, comorbidity profiles may have evolved. Clinical Trials in Organ Transplantation in Children-04 is a multicenter, prospective, cohort study assessing the impact of pre-transplant sensitization on outcomes after pediatric heart transplantation. This sub-study reports 1-year outcomes among recipients without pre-transplant donor-specific antibodies (DSAs). We recruited consecutive candidates (<21 years) at 8 centers. Sensitization status was determined by a core laboratory. Immunosuppression was standardized as follows: Thymoglobulin induction with tacrolimus and/or mycophenolate mofetil maintenance. Steroids were not used beyond 1 week. Rejection surveillance was by serial biopsy. There were 240 transplants. Subjects for this sub-study (n = 186) were non-sensitized (n = 108) or had no DSAs (n = 78). Median age was 6 years, 48.4% were male, and 38.2% had congenital heart disease. Patient survival was 94.5% (95% confidence interval, 90.1–97.0%). Freedom from any type of rejection was 67.5%. Risk factors for rejection were older age at transplant and presence of non-DSAs pre-transplant. Freedom from infection requiring hospitalization/intravenous anti-microbials was 75.4%. Freedom from rehospitalization was 40.3%. New-onset diabetes mellitus and post-transplant lymphoproliferative disorder (PTLD) occurred in 1.6% and 1.1% of subjects, respectively. There was no decline in renal function over the first year. Corticosteroids were used in 14.5% at 1 year. Pediatric heart transplantation recipients without DSAs at transplant and managed with a steroid avoidance regimen have excellent short-term survival and a low risk of first-year diabetes mellitus and PTLD. Rehospitalization remains common. These contemporary observations allow for improved caregiver and/or patient counseling and provide the necessary outcomes data to help design future randomized controlled trials. [ABSTRACT FROM AUTHOR]

Abstract Introduction Because health care reimbursement is being linked to discharge quality and patient satisfaction, this quality improvement initiative reviewed the outcomes of embedding a pediatric nurse practitioner within the resident team at an academic medical facility. Methods The project was completed at a pediatric orthopedic unit at a large Southeastern U.S. academic medical facility. During the intervention, the pediatric nurse practitioner student completed daily rounds, communicated with the resident team, assessed readiness for discharge, provided patient education, and ensured that comprehensive discharge materials were completed. Results Analyses were completed for 219 patients (pre-intervention, n = 116; post-intervention, n = 103). Patient satisfaction was measured for provider communication and discharge. All areas experienced improvement, with provider communication benchmarks obtained. Ambulatory call volume decreased from 97 to 45 calls/100 patients. Discussion This study shows that embedding a pediatric nurse practitioner into the resident team helped improve patient satisfaction and reduce ambulatory workload by decreasing call volume. [ABSTRACT FROM AUTHOR]

Highlights • Existing traction equations predict values only for one mode of operation. • A unified traction algorithm is proposed for braked, towed, and powered wheels on dry sand. • The algorithm is developed using DROVE database. • The algorithm employs the ratio of contact pressure to cone index. • The new equation can be implemented in VTI and other off-road mobility models. Abstract Vehicle traction between the wheel and the ground surface is a critical design element for on-road and off-road mobility. Adequate traction in dry sand relates to the vehicle's ability to negotiate deserts, sand dunes, climb slopes, and ingress/egress along beaches. The existing traction equations predict values for only one mode of operation (braked, towed, or powered). In this article, we propose a unified algorithm for continuous prediction of traction over a range of braked, towed, and powered operations for wheels operating on sand. A database of laboratory and field records for wheeled vehicles, entitled Database Records for Off-road Vehicle Environments (DROVE), was used to develop the proposed algorithm. The algorithm employs the ratio of contact pressure to cone index as a primary variable to develop fitting parameters for a relationship between slip and traction. The performance of the algorithm is examined versus the measured data and is also compared against two alternative equations. The new equation showed higher correlation and lower error compared to the existing equations for powered wheels. The proposed equation can be readily implemented into off-road mobility models, eliminating the need for multiple traction equations for different modes of operation. [ABSTRACT FROM AUTHOR]

Objectives: 1) To explore the association between family caregivers' involvement in managing care recipients' medications and their information-seeking behavior related to caregiving; and 2) to examine the sources used by caregivers when seeking information.Methods: A retrospective analysis of cross-sectional data from 2 national studies, the 2011 National Health and Aging Trends Study (NHATS) and its supplement, the National Study of Caregiving (NSOC), was conducted. A nationally representative sample of community-dwelling adults (≥65 years of age) completed NHATS interviews, and a sample of their family caregivers participated in NSOC. Caregiver involvement in medication management was assessed with the use of 2 items asking caregivers if they helped keep track of care recipients' medications or helped with injecting medications. Information seeking was assessed with the use of an item asking caregivers if they ever looked for caregiving-related information.Results: Out of 1367 caregivers interviewed, 54% reported helping to keep track of care recipients' medications and 8.7% assisting with injecting medications. Approximately 10.2% (n = 149) of caregivers reported seeking information to help them care for their care recipients. Caregivers sought information primarily on their own either through online resources or asking friends or relatives (73.3%). Sixty-four percent also sought information from medical providers or social workers. Adult children of caregivers were more likely to seek information for their older adult parents, based on bivariate analysis (P <0.01). In multivariable-adjusted models, caregivers who helped to keep track of medications had 2.30 (95% confidence interval [CI] 1.18 to 4.51) times higher odds of seeking information to help them to provide care for their care recipients. Caregivers helping with injecting medications were less likely to seek information (odds ratio 0.32, 95% CI 0.14 to 0.76).Conclusion: Specific caregiver responsibilities, such as assisting with medication management activities, are associated with caregivers' information-seeking behavior related to care recipients' health. Health care providers, including pharmacists, can play an important role in helping caregivers to identify proper resources for information and in educating them about medication management. [ABSTRACT FROM AUTHOR]

The Primary Biliary Cholangitis (PBC) Obeticholic Acid (OCA) International Study of Efficacy (POISE) randomized, double-blind, placebo-controlled trial demonstrated that OCA reduced biomarkers associated with adverse clinical outcomes (ie, alkaline phosphatase, bilirubin, aspartate aminotransferase, and alanine aminotransferase) in patients with PBC. The objective of this study was to evaluate time to first occurrence of liver transplantation or death in patients with OCA in the POISE trial and open-label extension vs comparable non-OCA–treated external controls. Propensity scores were generated for external control patients meeting POISE eligibility criteria from 2 registry studies (Global PBC and UK-PBC) using an index date selected randomly between the first and last date (inclusive) on which eligibility criteria were met. Cox proportional hazards models weighted by inverse probability of treatment assessed time to death or liver transplantation. Additional analyses (Global PBC only) added hepatic decompensation to the composite end point and assessed efficacy in patients with or without cirrhosis. During the 6-year follow-up, there were 5 deaths or liver transplantations in 209 subjects in the POISE cohort (2.4%), 135 of 1381 patients in the Global PBC control (10.0%), and 281 of 2135 patients in the UK-PBC control (13.2%). The hazard ratios (HRs) for the primary outcome were 0.29 (95% CI, 0.10–0.83) for POISE vs Global PBC and 0.30 (95% CI, 0.12–0.75) for POISE vs UK-PBC. In the Global PBC study, HR was 0.20 (95% CI, 0.03–1.22) for patients with cirrhosis and 0.31 (95% CI, 0.09–1.04) for those without cirrhosis; HR was 0.42 (95% CI, 0.21–0.85) including hepatic decompensation. Patients treated with OCA in a trial setting had significantly greater transplant-free survival than comparable external control patients. [Display omitted] Patients with primary biliary cholangitis treated with obeticholic acid in the POISE study had fewer deaths and liver transplants vs comparable patients in the Global PBC and UK-PBC disease registries. [ABSTRACT FROM AUTHOR]

Modeling and simulation of vehicles in sand is critical for characterizing off-road mobility in arid and coastal regions. This paper presents improved algorithms for calculating sinkage ( z ) of wheeled vehicles operating on loose dry sand. The algorithms are developed based on 2737 tests conducted on sand with 23 different wheel configurations. The test results were collected from Database Records for Off-road Vehicle Environments (DROVE), a recently developed database of tests conducted with wheeled vehicles operating in loose dry sand. The study considers tire diameters from 36 to 124 cm with wheel loads of 0.19–36.12 kN. The proposed algorithms present a simple form of sinkage relationships, which only require the ratio of the wheel ground contact pressure and soil strength represented by cone index. The proposed models are compared against existing closed form solutions defined in the Vehicle Terrain Interface (VTI) model. Comparisons suggest that incorporating the proposed models into the VTI model can provide comparable predictive accuracy with simpler algorithms. In addition to simplicity, it is believed that the relationship between cone index (representing soil shear strength) and the contact pressure (representing the applied pressure to tire-soil interface) can better capture the physics of the problem being evaluated. [ABSTRACT FROM AUTHOR]

Background Deficits in emotional processing can be detected in the pre-manifest stage of Huntington's disease and negative emotion recognition has been identified as a predictor of clinical diagnosis. The underlying neuropathological correlates of such deficits are typically established using correlative structural MRI studies. This approach does not take into consideration the impact of disruption to the complex interactions between multiple brain circuits on emotional processing. Therefore, exploration of the neural substrates of emotional processing in pre-manifest HD using fMRI connectivity analysis may be a useful way of evaluating the way brain regions interrelate in the period prior to diagnosis. Methods We investigated the impact of predicted time to disease onset on brain activation when participants were exposed to pictures of faces with angry and neutral expressions, in 20 pre-manifest HD gene carriers and 23 healthy controls. On the basis of the results of this initial study went on to look at amygdala dependent cognitive performance in 79 Huntington's disease patients from a cross-section of disease stages (pre-manifest to late disease) and 26 healthy controls, using a validated theory of mind task: “the Reading the Mind in the Eyes Test” which has been previously been shown to be amygdala dependent. Results Psychophysiological interaction analysis identified reduced connectivity between the left amygdala and right fusiform facial area in pre-manifest HD gene carriers compared to controls when viewing angry compared to neutral faces. Change in PPI connectivity scores correlated with predicted time to disease onset ( r =0.45, p <0.05). Furthermore, performance on the “Reading the Mind in the Eyes Test” correlated negatively with proximity to disease onset and became progressively worse with each stage of disease. Conclusion Abnormalities in the neural networks underlying social cognition and emotional processing can be detected prior to clinical diagnosis in Huntington's disease. Connectivity between the amygdala and other brain regions is impacted by the disease process in pre-manifest HD and may therefore be a useful way of identifying participants who are approaching a clinical diagnosis. Furthermore, the “Reading the Mind in the Eyes Test” is a surrogate measure of amygdala function that is clinically useful across the entire cross-section of disease stages in HD. [ABSTRACT FROM AUTHOR]

Background: Few instruments have been developed to assess the risk of self-harm by psychiatric patients and the evidence for their predictive validity is limited. Given that individuals who self-harm may also engage in other-directed aggression, and that the behaviour can be a precursor to violence, we tested whether, and for which groups, the commonly used violence risk assessment HCR-20 demonstrated predictive validity for self-harm. Procedures: A pseudo-prospective cohort study (N = 504) was conducted in a UK secure/forensic mental health setting using routinely collected data. HCR-20 assessments were completed by the clinical team and incidents of self-harm during the 3 months following assessment were coded from patient records. Findings: The HCR-20 total score, H10 and R5 subscales, and SJ for violence significantly predicted self-harm; however, AUC values did not demonstrate large effect sizes (range .345 to .749). Personality disorder and impulsivity were the strongest predictors of self-harm, but the R5 scale contained the greatest proportion of relevant items. Predictive efficacy was superior for women compared with men and for those with schizophrenia or personality disorder compared with organic and developmental disorders. Conclusions: The HCR-20 appears to be a significant predictor of self-harm. It may be possible to supplement HCR-20 ratings with case specific knowledge and additional known risk factors for self-harm to make a valuable summary judgement about the behaviour and thus minimise the need for multiple assessment tools. [ABSTRACT FROM AUTHOR]