County Populations Research Articles

Spatial and temporal autocorrelations affect Taylor's law for US county populations: Descriptive and predictive models.

Understanding the spatial and temporal distributions and fluctuations of living populations is a central goal in ecology and demography. A scaling pattern called Taylor's law has been used to quantify the distributions of populations. Taylor's law asserts a linear relationship between the logarithm of the mean and the logarithm of the variance of population size. Here, extending previous work, we use generalized least-squares models to describe three types of Taylor's law. These models incorporate the temporal and spatial autocorrelations in the mean-variance data. Moreover, we analyze three purely statistical models to predict the form and slope of Taylor's law. We apply these descriptive and predictive models of Taylor's law to the county population counts of the United States decennial censuses (1790–2010). We find that the temporal and spatial autocorrelations strongly affect estimates of the slope of Taylor's law, and generalized least-squares models that take account of these autocorrelations are often superior to ordinary least-squares models. Temporal and spatial autocorrelations combine with demographic factors (e.g., population growth and historical events) to influence Taylor's law for human population data. Our results show that the assumptions of a descriptive model must be carefully evaluated when it is used to estimate and interpret the slope of Taylor's law.

Breast Cancer Screening in Inner City and County Populations: A Tale of Two Centers.

New York's statewide "Get Screened, No Excuses" campaign has been one of the nation's most aggressive actions to improve access to breast cancer screening. Inner city and suburban county medical centers' initiatives were studied to compare outcomes of breast cancer screening and factors that influence access to care. Women delinquent in breast cancer screening one year or greater were offered patient navigator services to aid in timely breast cancer screening. Time-to-event completion rates among different stages of breast cancer screening stages in City and County women were compared. Time-to-event completion rates among different stages of breast cancer screening stages. 2505 women aged ≥40years accepted PN services. Mean (SD) age of patients was 56.2 (10) years. The mean (SD) age of those who completed breast screening vs. those who did not was 56.8 (10) and 52.5 (.9) years, respectively (P < .01). The rates of screening completion during physical examination, mammography and biopsy stages were 74%, 78% and 100% in City vs. 98%, 85% and 100% in County, respectively (P < .001). Screening phase was the significant predictor of time to completion for breast cancer screening in Cox regression analysis. Over 85% of women completed the breast cancer screening, 74% in City and 97.6% in County (P < .001). Screening phase is an important predictor of time-to complete breast cancer screening. Center location served as the effect modifier of the relationship. The rate of completing the screening was significantly higher and faster among Suburban County compared to Inner City women.

Abstract PO-270: The validation and redevelopment of a risk prediction model identifying patients unlikely to complete a colonoscopy following an abnormal FIT test in community clinics

Abstract Background: Fecal testing (FIT) is an effective screening tool for colorectal cancer. If a FIT is abnormal, a follow-up colonoscopy is necessary to remove polyps or find cancers. Predicting which patients may be at risk for failing to follow-up on an abnormal fecal test could help identify patients in need of early interventions aimed at completing a colonoscopy. Using predictive analytics to determine who is unlikely to follow-up will allow health systems to tailor interventions and outreach. Understanding the application of predictive analytics across health systems is imperative to providing appropriate care to distinct patient populations. Early interventions could decrease the disease burden if colorectal cancer is found at earlier stages. Methods: We compare two models created in two different settings. The models were created from data from FQHC’s and Logistic and Cox regressions to validate and redevelop a risk prediction model among a retrospective dataset of patients with abnormal FIT results. Results: The initial FQHC risk model included eight variables including race, clinic system, prior no-shows, insurance, prior flu shots, age, indication of anti-coagulation use, and income inequality. However, the model did not validate in a large similar health system in the Pacific Northwest. Risk factors for colonoscopy varied by county, clinics, regions, and patient populations. Inner and outer setting variables, like referral workflows and access to colonoscopy, contributed to the likelihood of a patient completing their screening. The second model retained most predictors except for anti-coagulation use, and included new predictors like language, homeless status, prior screenings, and a comorbidity index. Conclusions: Application of a risk model helps tailor interventions to help patients complete the continuum of screening for colorectal cancer. However, health systems differ, and precision medicine is best applied when risk is understood in context and interventions are tailored for specific populations predictors. Citation Format: Amanda F. Petrik, Eric S. Johnson, Matthew Slaughter, Andreea Rawlings, Michael Leo, Jamie Thompson, Ricardo Jimenez, Gloria D. Coronado. The validation and redevelopment of a risk prediction model identifying patients unlikely to complete a colonoscopy following an abnormal FIT test in community clinics [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-270.

Poverty, the U.S. South, and the SRSA

This paper is a broad expansion of an SRSA Research Fellows Address presented in Roslyn, Virginia on April 16th, 2019. In it, I extol the virtues of poverty research, particularly that focused on the U.S. where households living on less than $4/day/person compose the largest shares of county populations. I note that two factors that are the hallmark of such extreme poverty - lack of a vehicle and lack of internet service - are forcing poor household to perceive themselves as ever more isolated, for greater accessibility for the rest of the U.S. population amplifies the gap created by their deficiency. This is because others expect everyone has such access. Southern areas with persistent poverty - the Black Belt, the Mississippi Delta, and Appalachia - have concentrations of such extreme poor and also have deficient access to the rest of the world. I suggest that Americans should find away to ameliorate this condition. I conclude by encouraging my SRSA colleagues to do what they do best, but with a poverty tilt, as a means of petitioning policy makers and the public.

Virtual Model Testing of Widad Psychetra Door (WPD) & Extraversion Personality Type

The purpose of this paper is to address the new invention - Widad Psychetra Door (WPD) on how re-generate low costing instrument of psychology games (combining perceptual illusions and active focus repetitive behavior) to Re-Instrumental Scale for basic Personality Test among teenagers’ personality. This study is conducted to identify the repetitive level difficulty of segmented in WPD with extroversion personality type among 10 adolescents. This research used a qualitative methodology through interviewed and data was analysed used content analysis with 10 respondents in age range between adolescent are 14 to 16 years old. The segmented difficulty level shape is based on Holland theories of personality and whereas extraversion personality type defines based on Big Five Personality Model by Jung. Supported literature were discussed further with current research’s scholars in early 2010s. The result shown the difficulty level is very high at the third segmented which is accordance with the personality type own by the respondents (extraversion type). This research is only limit only in Kuantan City area only and one school population. Recommended further studies must be access to bigger population. Extraversion personality type of adolescent can be measure and compare between two bigger county populations.

Trends in Uninsured Rates Before and After Medicaid Expansion in Counties Within and Outside of the Diabetes Belt

To examine trends in uninsured rates between 2012 and 2016 among low-income adults aged <65 years and to determine whether the Patient Protection and Affordable Care Act (ACA), which expanded Medicaid, impacted insurance coverage in the Diabetes Belt, a region across 15 southern and eastern U.S. states in which residents have high rates of diabetes. Data for 3,129 U.S. counties, obtained from the Small Area Health Insurance Estimates and Area Health Resources Files, were used to analyze trends in uninsured rates among populations with a household income ≤138% of the federal poverty level. Multivariable analysis adjusted for the percentage of county populations aged 50-64 years, the percentage of women, Distressed Communities Index value, and rurality. In 2012, 39% of the population in the Diabetes Belt and 34% in non-Belt counties were uninsured (P < 0.001). In 2016 in states where Medicaid was expanded, uninsured rates declined rapidly to 13% in Diabetes Belt counties and to 15% in non-Belt counties. Adjusting for county demographic and economic factors, Medicaid expansion helped reduce uninsured rates by 12.3% in Diabetes Belt counties and by 4.9% in non-Belt counties. In 2016, uninsured rates were 15% higher for both Diabetes Belt and non-Belt counties in the nonexpansion states than in the expansion states. ACA-driven Medicaid expansion was more significantly associated with reduced uninsured rates in Diabetes Belt than in non-Belt counties. Initial disparities in uninsured rates between Diabetes Belt and non-Belt counties have not existed since 2014 among expansion states. Future studies should examine whether and how Medicaid expansion may have contributed to an increase in the use of health services in order to prevent and treat diabetes in the Diabetes Belt.

Analyzing and interpreting spatial and temporal variability of the United States county population distributions using Taylor's law.

We study the spatial and temporal variation of the human population in the United States (US) counties from 1790 to 2010, using an ecological scaling pattern called Taylor's law (TL). TL states that the variance of population abundance is a power function of the mean population abundance. Despite extensive studies of TL for non-human populations, testing and interpreting TL using data on human populations are rare. Here we examine three types of TL that quantify the spatial and temporal variation of US county population abundance. Our results show that TL and its quadratic extension describe the mean-variance relationship of county population distribution well. The slope and statistics of TL reveal economic and demographic trends of the county populations. We propose TL as a useful statistical tool for analyzing human population variability. We suggest new ways of using TL to select and make population projections.

How to Create an Effective Thematic Map

Considering the evolution of automatic mapping programs and the huge amount of available data, the key elements that go into creating thematic maps are presented so that those less familiar with map-making might be able to craft accurate, reliable and illustrative maps.Here, we used ArcGIS Pro in order to exemplify the process of creating thematic maps presenting correlations between the number of emergency/total 112 calls and the population of Romanian counties. These freely-available data were classified using Natural Brakes, Quantile, Equal Interval, Geometric Interval, Standard Deviation, Defined Interval and Manual Interval, so as to highlight their relevant aspects. The value of the goodness of absolute deviation fit was calculated for each method and each data set. The maps were then created using combined choropleth and proportional symbol methods. The ratio between the total number of 112 calls and the county populations, structured into five classes, has been represented using choropleth method. On the resulting map, emergency calls have been represented with proportional symbols. Furthermore, aspects related to the other map elements were presented all in one place, in order to create a thematic map that would be easy to understand and interpret.The findings of the present paper could be used by those who want to represent their own data in a very suggestive and reliable manner, without having had any cartographic training beforehand. They could also more easily interpret their datasets and be able to take the necessary steps in their own domains of activity.

Spatiotemporal characteristics and driving mechanisms of arable land in the Beijing-Tianjin-Hebei region during 1990-2015

This paper is an analysis of the spatiotemporal evolution characteristics of arable land in the Beijing-Tianjin-Hebei region from 1990 to 2015 and detects the driving factors of arable land change. On the basis of the study, the existing problems of arable land are discussed and some suggestions to promote regional rural development are proposed. The conclusions are as follows: (1) The proportion of arable land gradually decreased from 1990 to 2015 and the proportion of arable land in the south of the Beijing-Tianjin-Hebei region was larger than that in the north of the Beijing-Tianjin-Hebei region: arable land with a proportion of more than 75% lies in the low elevation and slope. The proportion of arable land in Beijing has also decreased faster than in other regions because most arable land was converted primarily into construction land due to urban expansion. (2) The mechanism showed that county economies and populations influenced the change in the quantity of arable land, and the position and natural conditions influenced the pattern changes in arable land. (3) Finally, this paper details some suggestions on the terms of legal institutions, the land consolidation project, and developing modern agriculture and industrial upgrading, which could provide scientific support for rural sustainable development and arable land protection in the Beijing-Tianjin-Hebei region.

Rural Depopulation: Growth and Decline Processes over the Past Century

AbstractThis article highlights the rise and geographic spread of depopulation in rural America over the past century. “Depopulation” refers to chronic population losses that prevent counties from returning to an earlier period of peak population size. In this article, we identify 746 depopulating counties—mostly nonmetropolitan—representing 24 percent of all U.S. counties. More than 46 percent of remote rural counties are depopulating compared to 24 percent of the adjacent nonmetropolitan counties and just 6 percent of metropolitan counties. Rural county populations often peaked in size during the 1940s and 1950s, especially in the agricultural heartland. Depopulation today reflects a complex interplay of chronic net out‐migration and natural decrease that is rooted in the past. Depopulation not only is a direct result of persistent out‐migration but also reflects large second‐order effects expressed in declining fertility and rising mortality (usually associated with population aging). Depopulation has become a signature demographic phenomenon in broad regions of rural America.

Session 100 - A Path Forward: A Culturally Relevant Psychosocial Intervention for Depression in Cognitive Impaired Older Adults

Abstract: As the geriatric population increases, it has also become more diverse. According to the 2011 U.S. Census Bureau, 8 % of older adults are Non-Hispanic Black and 7% are Hispanic/Latino. Similarly in Bronx County New York, 53% of patients speak a language other than English in the home. The Bronx has a growing Hispanic and non-Hispanic Black population, which faces a high prevalence of poverty, medical morbidity and comorbid depression. In a pilot study conducted at the Bronx-based Montefiore Geriatric Neurology Center, rates of depression were over 40%. Ethnic minorities are less likely to be included in research trials and have less access to innovative treatment modalities. Hispanics and Non-Hispanic Blacks are also less likely to seek mental health treatment and to find antidepressants acceptable. According to the Alzheimer's Association, about 200,000 Latinos in the United States have Alzheimer's disease dementia (AD). Moreover the highest prevalence of dementia is found in Latin America at 8.5%. In 2004 Montefiore Home Care in collaboration with Cornell Westchester division established the Montefiore Home Care Geriatric Psychiatry Program (MHC-GPP) to provide depression screening for homebound, medically ill older adults. During the 13 years of this program, the MHC-GPP has not only identified and treated homebound adults with depression, but has reached a population comprised of mostly Hispanics and Non-Hispanic Blacks (49% and 30%, respectively). Additionally the program has identified cognitive disorders as 3/4 of the new diagnoses identified by the MHC-GPP were neurocognitive disorders. Previous literature has shown depression to be one of the most common neuropsychiatric symptoms of AD and dementia related disorders, with a prevalence from 25% to 75% of patients. Unfortunately, previous trials have also shown that depression in the setting of AD is minimally responsive to antidepressants. This population is also unlikely to benefit from short term evidenced based psychotherapeutic modalities such as Problem Solving Therapy (PST) due to cognitive limitations. Furthermore, depending on state mental health regulations, patients with neuropsychiatric symptoms of dementia cannot be served in a mental health clinic. Kiosses and colleagues developed a non-pharmacological intervention to treat older adults with depression in the setting of dementia known as Problem Adaptation Therapy (PATH). PATH is an evidenced based intervention using personalized strategies to decrease depression and disability in older adults with depression and cognitive impairment. To achieve this goal, PATH utilizes a simplified problem solving approach, employing compensatory strategies, environmental adaptations to bypass cognitive and functional limitations while incorporating the caregiver when necessary. In a randomized trial, PATH was yielded a significantly greater reduction in depression and disability when compared to home delivered supportive psychotherapy. In 2016, Montefiore and Cornell Westchester, collaborated again in a pilot study to adapt PATH to serve the diverse Bronx and Westchester county populations. In this program PATH is delivered in English and Spanish and in the home or office, in order to evaluate the efficacy of this model in all settings and establish the sustainability of this model within a larger and diverse health network. During this session, the presenters will describe the development and advances in the PATH model and various adaptations and how this model was adapted in Montefiore Medical Center health network. The director of MHC-GPP will discuss how the PATH is incorporated into a certified home health agency (CHHA) to reach homebound adults with complex medical and social backgrounds. Finally the presenters will discuss implications for future directions in aging research centered on emotional dysregulation and dementia while impacting a more diverse population of older adults.

Managed care and inpatient mortality in adults: effect of primary payer

BackgroundBecause managed care is increasingly prevalent in health care finance and delivery, it is important to ascertain its effects on health care quality relative to that of fee-for-service plans. Some stakeholders are concerned that basing gatekeeping, provider selection, and utilization management on cost may lower quality of care. To date, research on this topic has been inconclusive, largely because of variation in research methods and covariates. Patient age has been the only consistently evaluated outcome predictor. This study provides a comprehensive assessment of the association between managed care and inpatient mortality for Medicare and privately insured patients.MethodsA cross-sectional design was used to examine the association between managed care and inpatient mortality for four common inpatient conditions. Data from the 2009 Healthcare Cost and Utilization Project State Inpatient Databases for 11 states were linked to data from the American Hospital Association Annual Survey Database. Hospital discharges were categorized as managed care or fee for service. A phased approach to multivariate logistic modeling examined the likelihood of inpatient mortality when adjusting for individual patient and hospital characteristics and for county fixed effects.ResultsResults showed different effects of managed care for Medicare and privately insured patients. Privately insured patients in managed care had an advantage over their fee-for-service counterparts in inpatient mortality for acute myocardial infarction, stroke, pneumonia, and congestive heart failure; no such advantage was found for the Medicare managed care population. To the extent that the study showed a protective effect of privately insured managed care, it was driven by individuals aged 65 years and older, who had consistently better outcomes than their non-managed care counterparts.ConclusionsPrivately insured patients in managed care plans, especially older adults, had better outcomes than those in fee-for-service plans. Patients in Medicare managed care had outcomes similar to those in Medicare FFS. Additional research is needed to understand the role of patient selection, hospital quality, and differences among county populations in the decreased odds of inpatient mortality among patients in private managed care and to determine why this result does not hold for Medicare.

The investment of a new medical school in its local primary care community

Keele School of Medicine has an innovative new MBChB curriculum with a strong focus on primary care. Our students spend a minimum of 115 days in general practice. To describe the investment by the school in the local primary care community. We collated data on list sizes of current undergraduate teaching practices, county populations and the investment in practices' teaching skills and physical premises. Between academic years 2010-11 and 2012-13 a total of 118 (annual mean of 99) practices contributed to teaching across six counties, providing care for 655 229 people. Forty-five per cent of 243 practices in Staffordshire and Shropshire teach. They serve 51% of the two counties' population. We have invested £1.62 million in the premises of 25 practices providing services for 18% of people in Staffordshire and Shropshire, £273 000 in a rural campus in Shropshire, and £99 387 in set-up grants. We have conducted 249 practice development visits. There were 540 attendances at tutor development sessions. We have had a total of 2300 hours of face-to-face contact with our practices. The school has made a major investment in general practice in its area, contributing to the development of general practitioners and investing in practice premises.

Judges’ Perceptions of the Nebraska CASA Program

This article discusses judges’ perceptions of court appointed special advocates (CASA) programs in the rural state of Nebraska, as reported in two online surveys. The goal of CASA is “to train and support volunteers in advocating for safe and permanent homes for abused and neglected children” (CASA for Children 2013). One survey investigated the opinions of judges presiding in Nebraska counties that did not yet have a local CASA program; another was administered to judges in counties that did have a CASA program. A total of 36 judges completed a survey. Data from both surveys were analyzed separately and then compared to provide information regarding judges’ satisfaction with local programs and general perceptions of the Nebraska CASA Association. Results offer vital information for program growth and contain a hopeful tone for the Nebraska CASA Association and their goal of providing every child a voice by 2020. Both groups of judges expressed support for CASA programs overall, although judges in counties with CASA programs expressed significantly more support than those in counties without CASA programs. Judges presiding in counties with lower county populations and lower numbers of children in foster care also tended to be more supportive of the CASA program. Additional information was collected from judges regarding readiness for the development of CASA programs in counties not yet utilizing a program and perceived strengths and limitations of existing CASA programs. This study has the capacity to inform CASA programs seeking similar information to guide program growth in other states.

Community-wide cardiovascular disease prevention programs and health outcomes in a rural county, 1970-2010.

Few comprehensive cardiovascular risk reduction programs, particularly those in rural, low-income communities, have sustained community-wide interventions for more than 10 years and demonstrated the effect of risk factor improvements on reductions in morbidity and mortality. To document health outcomes associated with an integrated, comprehensive cardiovascular risk reduction program in Franklin County, Maine, a low-income rural community. Forty-year observational study involving residents of Franklin County, Maine, a rural, low-income population of 22,444 in 1970, that used the preceding decade as a baseline and compared Franklin County with other Maine counties and state averages. Community-wide programs targeting hypertension, cholesterol, and smoking, as well as diet and physical activity, sponsored by multiple community organizations, including the local hospital and clinicians. Resident participation; hypertension and hyperlipidemia detection, treatment, and control; smoking quit rates; hospitalization rates from 1994 through 2006, adjusted for median household income; and mortality rates from 1970 through 2010, adjusted for household income and age. More than 150,000 individual county resident contacts occurred over 40 years. Over time, as cardiovascular risk factor programs were added, relevant health indicators improved. Hypertension control had an absolute increase of 24.7% (95% CI, 21.6%-27.7%) from 18.3% to 43.0%, from 1975 to 1978; later, elevated cholesterol control had an absolute increase of 28.5% (95% CI, 25.3%-31.6%) from 0.4% to 28.9%, from 1986 to 2010. Smoking quit rates improved from 48.5% to 69.5%, better than state averages (observed - expected [O - E], 11.3%; 95% CI, 5.5%-17.7%; P < .001), 1996-2000; these differences later disappeared when Maine's overall quit rate increased. Franklin County hospitalizations per capita were less than expected for the measured period, 1994-2006 (O - E, -17 discharges/1000 residents; 95% CI -20.1 to -13.9; P < .001). Franklin was the only Maine county with consistently lower adjusted mortality than predicted over the time periods 1970-1989 and 1990-2010 (O - E, -60.4 deaths/100,000; 95% CI, -97.9 to -22.8; P < .001, and -41.6/100,000; 95% CI, -77.3 to -5.8; P = .005, respectively). Sustained, community-wide programs targeting cardiovascular risk factors and behavior changes to improve a Maine county's population health were associated with reductions in hospitalization and mortality rates over 40 years, compared with the rest of the state. Further studies are needed to assess the generalizability of such programs to other US county populations, especially rural ones, and to other parts of the world.

The influence of differential response on decision-making in child protective service agencies

Differential response (DR) profoundly changes the decision pathways of public child welfare systems, yet little is known about how DR shapes the experiences of children whose reports receive an investigation rather than an alternate response. Using data from the National Child Abuse and Neglect Data System (NCANDS), this study examined the relationship between DR implementation and decision outcomes in neglect cases, as measured by investigation, substantiation, and removal rates in 297 U.S. counties. Multivariate regression models included county-level measures of child poverty and proportions of African American children. Path analyses were also conducted to identify mediating effects of prior decision points and moderating effects of DR on poverty and race's influence on decision outcomes. Results indicate that compared to non-DR counties, those implementing DR have significantly lower investigation and substantiation rates within county populations but higher substantiation rates among investigated cases. Regression models showed significant reductions in removal rates associated with DR implementation, but these effects became insignificant in path models that accounted for mediation effects of previous decision points. Findings also suggest that DR implementation may reduce the positive association between child poverty rates and investigation rates, but additional studies with larger samples are needed to confirm this moderation effect. Two methods of calculating decision outcomes, population- and decision-based enumeration, were used, and policy and research implications of each are discussed. This study demonstrates that despite their inherit complexity, large administrative datasets such as NCANDS can be used to assess the impact of wide-scale system change across jurisdictions.

Reproductive mode and fine-scale population genetic structure of grape phylloxera (Daktulosphaira vitifoliae) in a viticultural area in California

BackgroundGrape phylloxera (Daktulosphaira vitifoliae) is one of the world’s most important viticultural pests. However, the reproductive mode, genetic structure and host adaptation of phylloxera in various viticultural environments remains unclear. We examined reproductive mode and genetic structure of phylloxera by analyzing microsatellite makers across the samples from four vineyard-sites in California.ResultThe phylloxera populations in California are believed to have predominantly parthenogenetic reproduction. Therefore, genetic diversity of phylloxera is expected to be limited. However, this study showed relatively high levels of diversity in Napa and Yolo county populations with a large number of unique genotypes, average number of alleles (2.1 to 2.9) and observed heterozygosities (0.330 to 0.388) per vineyard-sites. Reproduction diversity index (G: N—unique genotypes versus number of samples) ranged from 0.500 to 0.656 among vineyard-sites. Both significant and non-significant Psex (probability of sexual reproduction) were observed among different repeated genotypes within each vineyard. Moreover, high variation of FIS was observed among different loci in each vineyard-site. Genetic structure analysis (UPGMA) and various measures of population differentiations (FST, PCA, and gene flow estimates) consistently separated AXR#1 (Vitis vinifera x V. rupestris—widely planted in California during the 1960s and 1970s) associated populations from the populations associated with other different rootstocks.ConclusionGenetic diversity, G: N ratio, Psex and FIS consistently suggested the occurrence of both parthenogenetic and sexual reproduction in California populations. This study clearly identified two major groups of phylloxera obtained from various rootstocks, with one group exclusively associated with only AXR#1 rootstock, defined as “biotype B”, and another group associated with vinifera-based rootstocks, known as “biotype A”.

Hiatal Hernia Is Associated With an Increased Prevalence of Atrial Fibrillation in Young Patients.

Purpose: Hiatal hernia (HH) causes protrusion of the stomach into the chest cavity, directly impinging on the left atrium and possibly increasing predisposition to atrial arrhythmogenesis. However, such association has not been fully explored. The objective was to determine if an association between HH and atrial fibrillation (AF) exists and whether there are age- and sex-related differences. Methods: Adult patients diagnosed with HH from 1976 to 2006 at Mayo Clinic Rochester, Minnesota, were evaluated for AF. The number of patients with AF and HH was compared to age- and sex-matched patients with AF reported in the general population. Long-term outcomes were compared to corresponding county and state populations. Results: During the 30-year period, 111,429 patients were diagnosed with HH (mean age 61.4 ± 13.8 years, 47.9% male) and 7,865 patients (7.1%) also had a diagnosis of AF (mean age 73.1 ± 10.5 years; 55% male). In younger patients (<55 years), the occurrence of AF was 17.5-fold higher in men with HH and 19-fold higher in women with HH compared to the frequency of AF reported in the general population. Incidence of heart failure for patients with AF and HH was worse compared to the overall county population, but better than for those with AF. Similarly, mortality was worse in patients with AF and HH compared to the overall state population, but better than for those with AF in the county. Conclusion: Hiatal hernia appears to be associated with increased frequency of AF in both men and women of all age groups, but particularly in young patients. Further studies are needed to investigate this possible association and underlying mechanism.

Why Do So Few Minority People Visit National Parks? Visitation and the Accessibility of “America's Best Idea”

It has been said that national parks are “America's Best Idea,” they are among the most famous and instantly recognizable places in the country, and they attract visitors from all over the world. Yet visitors to these sites are overwhelmingly white. A number of theoretical perspectives have been proposed for the absence of minority visitors, including socioeconomic marginality, differing cultural norms, and the lingering legacy of discrimination, but geography is not one of the usual explanations. Given the strong associations between particular regions of the country and the locations of parks, as well as the uneven spatial distribution of population, the absence of geography as an explanation is striking. We examine this issue with the expectation that geography is an important part of the explanation for low minority visitation rates. Put simply, do potential minority visitors live anywhere near national park units? Are they more likely to visit the ones to which they live nearest? This study uses the geographic concept of accessibility to examine the spatial relationships between national parks and potential minority visitors. Accessibility was measured using driving times between each of 285 parks and county populations, with the results compared to a visitation database compiled for fifty-one park units. There is clearly a relationship between park visitation and the location of minority populations, in the sense that racial or ethnic minorities are disproportionately represented at closer and smaller national parks.

Canada frostweed (Helianthemum canadense(L.) Michx.; Cistaceae) at the northeastern limit of its range: implications for conservation

Canada frostweed (Helianthemum canadense) is a perennial herb whose abundance and habitat are declining in Nova Scotia. These sites mark the northeastern limit of this species with nearest populations occurring in Maine and Quebec. To determine the genetic structure of northeastern populations, we used amplified fragment length polymorphisms to examine individuals from Nova Scotia, Maine, New Hampshire, and Quebec. Cluster analyses and analysis of molecular variance identified four groups: (i) Queens County, Nova Scotia; (ii) Kings County, Nova Scotia; (iii) Quebec; and (iv) Northeastern New England. New England samples revealed evidence of gene flow among populations within that region, and several individuals from Quebec and Queens County, Nova Scotia, were assigned to the same cluster. The majority of individuals from Kings County were assigned to a separate cluster from that associated with Queens County, indicating two distinct populations within Nova Scotia. Differences between Nova Scotia populations may be attributed to isolation and drift, or separate postglacial colonization events. We recommend that Queens County and Kings County populations be considered as discrete units for conservation and, because Nova Scotia populations are distinct from other populations in eastern Canada and northeastern United States, we suggest that conservation of populations at the northeastern limits of the range of H. canadense is warranted.