Fractal analysis of track geometry data

ABSTRACT A Federal Railroad Administration sponsored research project has been ongoing to explore the use of Fractal Analysis of track geometry data for indication of track geometry roughness, maintenance planning and track substructure condition assessment. Fractal analysis provides unique numerical values (fractal dimensions) that characterize railway track geometry patterns. The fractal dimensions can be used for effective maintenance planning by providing meaningful parameters for geometry deterioration modeling, and by potentially providing information about the actual condition of the track by precise quantification of the geometry patterns. The paper will present a lucid discussion of fractal theory and will demonstrate its usefulness for quantifying railroad geometry data by highlighting key aspects of the research results. This paper also discusses the relationship between track structure conditions and fractal dimensions for use in maintenance planning and condition evaluation

Factors Associated with Arkansans’ First Use of Telehealth during the COVID-19 Pandemic

Objective. To examine the factors associated with the first use of telehealth during the COVID-19 pandemic using Andersen’s Model of Healthcare Utilization. Andersen’s Model of Healthcare Utilization allowed the categorization of the independent variables into the following: (1) predisposing factors, including sociodemographic variables and health beliefs; (2) enabling factors, including socioeconomic status and access to care; and (3) need for care, including preexisting or newly diagnosed conditions and reasons to seek out care or to utilize a new mode of care. Methods. Potential respondents (n = 4,077) were identified for recruitment from a volunteer registry in Arkansas. Recruitment emails provided a study description, the opportunity to verify meeting the study’s inclusion criteria and to consent for participation, and a link to follow to complete the survey online. The online survey responses were collected between July and August of 2020 (n = 1,137). Results. Telehealth utilization included two categories: (1) utilizers reported the first use of telehealth services during the pandemic, and (2) nonutilizers reported they had never used telehealth. Lower odds of reporting telehealth utilization during the pandemic were associated with race (Black; OR = 0:57, CI [0.33, 0.96]) and education (high School or less; OR = 0:45, CI [0.25, 0.83]). Higher odds of reporting telehealth utilization included having more than one provider (OR = 2:33, CI [1.30, 4.18]), more physical (OR = 1:12, CI [1.00, 1.25]) and mental (OR 1.53, CI [1.24, 1.88]) health conditions, and changes in healthcare delivery during the pandemic (OR = 3:49, CI [2.78, 4.38]). Conclusions. The results illustrate that disparities exist in Arkansans’ utilization of telehealth services during the pandemic. Future research should explore the disparities in telehealth utilization and how telehealth may be used to address disparities in care for Black Arkansans and those with low socioeconomic status

Association between Diagnosed Anxiety and Depression and Exposure to Life Stressors during the COVID-19 Pandemic

Research suggests that mental health disorders heighten the risk of exposure to life stressors. Drawing on a sample of 754 adults from a survey distributed at six primary care clinics, we examine whether adults who reported ever being diagnosed with depression or anxiety were more likely to experience an employment disruption, a housing disruption, and/or report more COVID-19-related stressors during the COVID-19 pandemic. Individuals who reported ever being diagnosed with depression reported a greater burden (B=.75) of COVID-19-related stressors. Those who reported ever being diagnosed with anxiety had higher odds of experiencing an employment disruption (OR=1.90) and a housing disruption (OR=2.92) and reported about one (B=.97) additional COVID-19-related stressor. Our results suggest that the COVID-19 pandemic may have deepened existing mental health disparities by exposing those with a depression or anxiety diagnosis to additional life stressors

N-(4-Chloro-1,3-benzothia­zol-2-yl)-2-(3-methyl­phen­yl)acetamide monohydrate

In the title compound, C16H13ClN2OS·H2O, the dihedral angle between the mean planes of the benzothia­zole ring system and the methylphenyl ring is 79.3 (6)°. The crystal packing features inter­molecular O—H⋯N, O—H⋯O and N—H⋯O hydrogen bonds involving the water mol­ecule and weak C—H⋯O, C—H⋯Cg and π–π stacking inter­actions [centroid–centroid distances = 3.8743 (7), 3.7229 (7) and 3.7076 (8) Å]

Prevalence and Associations between Food Insecurity and Overweight/Obesity among Native Hawaiian and Pacific Islander Adolescents

Abstract Objective: This study estimates the prevalence of, and associations between, family food insecurity and overweight/obesity among Native Hawaiian and Pacific Islander (NHPI) adolescents and explores sociodemographic factors which might have a moderation effect on the association. Design: Cross-sectional study using 2014 NHPI-National Health Interview Survey (NHIS) data reported by a parent or guardian. Family-level food security was assessed by the United States (US) Department of Agriculture 10-item questionnaire. BMI for age and sex >=85th and 95th percentiles defined overweight and obesity, respectively, according to US Centers for Disease Control and Prevention criteria. Setting: The US, including all 50 states and the District of Columbia. Participants: 383 NHPI adolescents aged 12-17 in the US. Results: A third (33.5%) of NHPI adolescents aged 12-17 were overweight (19.1%) or obese (14.4%); 8.1% had low food security; and 8.5% had very low food security. Mean family food security score was 1.06, which corresponds to marginal food security. We found no association between family food insecurity and adolescent overweight/obesity or between any other covariates and overweight/obesity, except for family Supplemental Nutrition Assistance Program (SNAP) participation. Odds of being overweight/obese were 77% lower for adolescents in families participating in SNAP (OR: 0.23, 95% CI: 0.08-0.64, p=0.007). The association between SNAP participation and lower odds of overweight/obesity was particularly pronounced for adolescent girls in food insecure families. Conclusions: The association between SNAP participation and lower odds of overweight/obesity suggests potential benefit of research to determine whether interventions to increase SNAP enrollment would improve NHPI adolescents’ health outcomes

Improving estimates of population status and trend with superensemble models

Fishery managers must often reconcile conflicting estimates of population status and trend. Superensemble models, commonly used in climate and weather forecasting, may provide an effective solution. This approach uses predictions from multiple models as covariates in an additional "superensemble" model fitted to known data. We evaluated the potential for ensemble averages and superensemble models (ensemble methods) to improve estimates of population status and trend for fisheries. We fit four widely applicable data-limited models that estimate stock biomass relative to equilibrium biomass at maximum sustainable yield (B/BMSY). We combined these estimates of recent fishery status and trends in B/BMSY with four ensemble methods: an ensemble average and three superensembles (a linear model, a random forest and a boosted regression tree). We trained our superensembles on 5,760 simulated stocks and tested them with cross-validation and against a global database of 249 stock assessments. Ensemble methods substantially improved estimates of population status and trend. Random forest and boosted regression trees performed the best at estimating population status: inaccuracy (median absolute proportional error) decreased from 0.42 -0.56 to 0.32 -0.33, rank-order correlation between predicted and true status improved from 0.02 - 0.32 to 0.44 - 0.48 and bias (median proportional error) declined from - 0.22 - 0.31 to - 0.12 - 0.03. We found similar improvements when predicting trend and when applying the simulation-trained superensembles to catch data for global fish stocks. Superensembles can optimally leverage multiple model predictions; however, they must be tested, formed from a diverse set of accurate models and built on a data set representative of the populations to which they are applied

Analysis of Genetic Linkage of HIV From Couples Enrolled in the HIV Prevention Trials Network 052 Trial

Background. The HIV Prevention Trials Network (HPTN) 052 trial demonstrated that early initiation of antiretroviral therapy (ART) reduces human immunodeficiency virus (HIV) transmission from HIV-infected adults (index participants) to their HIV-uninfected sexual partners. We analyzed HIV from 38 index-partner pairs and 80 unrelated index participants (controls) to assess the linkage of seroconversion events

Adverse Childhood Experiences of Urban and Rural Preschool Children in Poverty

Adverse childhood experiences (ACEs) have long-term health consequences. Young children in the southern part of the United States (US) are at greater risk than children in other parts of the US. This study assessed preschool children ACEs using a family-friendly tool, the Family Map (FMI), and compared children living in rural/urban areas while examining the potential moderation of race. The FMI–ACE score was examined as a total and two sub-scores. We found that race did not moderate the FMI–ACE score but that Black children (Cohen’s d = 0.52) and children in urban and large rural areas were at highest risk (Cohen’s d = 0.38). However, the subscale FMI–ACEs parenting risk was moderated by race such as that Black children were less at risk in rural areas than urban (Cohen’s d = 0.62). For FMI–ACEs environmental risk, race moderated risk such that Black children were most at risk in large rural areas but less so in small rural areas (Cohen’s d = 0.21). Hispanic children were most at risk in small rural areas and least in large rural environments. Findings from this study suggest that targeting the most at-risk children for interventions should consider the context including race and location