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Sample records for neighborhood weighted gaussian

  1. Gaussian variable neighborhood search for the file transfer scheduling problem

    Directory of Open Access Journals (Sweden)

    Dražić Zorica

    2016-01-01

    Full Text Available This paper presents new modifications of Variable Neighborhood Search approach for solving the file transfer scheduling problem. To obtain better solutions in a small neighborhood of a current solution, we implement two new local search procedures. As Gaussian Variable Neighborhood Search showed promising results when solving continuous optimization problems, its implementation in solving the discrete file transfer scheduling problem is also presented. In order to apply this continuous optimization method to solve the discrete problem, mapping of uncountable set of feasible solutions into a finite set is performed. Both local search modifications gave better results for the large size instances, as well as better average performance for medium and large size instances. One local search modification achieved significant acceleration of the algorithm. The numerical experiments showed that the results obtained by Gaussian modifications are comparable with the results obtained by standard VNS based algorithms, developed for combinatorial optimization. In some cases Gaussian modifications gave even better results. [Projekat Ministarstava nauke Republike Srbije, br. 174010

  2. How Neighborhood Disadvantage Reduces Birth Weight

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    Emily Moiduddin

    2008-06-01

    Full Text Available In this analysis we connect structural neighborhood conditions to birth outcomes through their intermediate effects on mothers’ perceptions of neighborhood danger and their tendency to abuse substances during pregnancy. We hypothesize that neighborhood poverty and racial/ethnic concentration combine to produce environments that mothers perceive as unsafe, thereby increasing the likelihood of negative coping behaviors (substance abuse. We expect these behaviors, in turn, to produce lower birth weights. Using data from the Fragile Families and Child Wellbeing Study, a survey of a cohort of children born between 1998 and 2000 and their mothers in large cities in the United States, we find little evidence to suggest that neighborhood circumstances have strong, direct effects on birth weight. Living in a neighborhood with more foreigners had a positive effect on birth weight. To the extent that neighborhood conditions influence birth weight, the effect mainly occurs through an association with perceived neighborhood danger and subsequent negative coping behaviors. Poverty and racial/ethnic concentration increase a mother’s sense that her neighborhood is unsafe. The perception of an unsafe neighborhood, in turn, associates with a greater likelihood of smoking cigarettes and using illegal drugs, and these behaviors have strong and significant effects in reducing birth weight. However, demographic characteristics, rather than perceived danger or substance abuse, mediate the influence of neighborhood characteristics on birth weight.

  3. Neighborhood racial composition and poverty in association with pre-pregnancy weight and gestational weight gain

    Directory of Open Access Journals (Sweden)

    Dara D. Mendez

    2016-12-01

    Full Text Available Background: Studies of neighborhood racial composition or neighborhood poverty in association with pregnancy-related weight are limited. Prior studies of neighborhood racial density and poverty has been in association with adverse birth outcomes and suggest that neighborhoods with high rates of poverty and racial composition of black residents are typically segregated and systematically isolated from opportunities and resources. These neighborhood factors may help explain the racial disparities in pre-pregnancy weight and inadequate weight gain. This study examined whether neighborhood racial composition and neighborhood poverty was associated with weight before pregnancy and weight gain during pregnancy and if this association differed by race. Methods: We used vital birth records of singleton births of 73,061 non-Hispanic black and white women in Allegheny County, PA (2003–2010. Maternal race and ethnicity, pre-pregnancy body-mass-index (BMI, gestational weight gain and other individual-level characteristics were derived from vital birth record data, and measures of neighborhood racial composition (percentage of black residents in the neighborhood and poverty (percentage of households in the neighborhood below the federal poverty were derived using US Census data. Multilevel log binomial regression models were performed to estimate neighborhood racial composition and poverty in association with pre-pregnancy weight (i.e., overweight/obese and gestational weight gain (i.e., inadequate and excessive. Results: Black women as compared to white women were more likely to be overweight/obese before pregnancy and to have inadequate gestational weight gain (53.6% vs. 38.8%; 22.5% vs. 14.75 respectively. Black women living in predominately black neighborhoods were slightly more likely to be obese prior to pregnancy compared to black women living in predominately white neighborhoods (PR 1.10; 95% CI: 1.03, 1.16. Black and white women living in high

  4. Neighborhood racial composition and poverty in association with pre-pregnancy weight and gestational weight gain.

    Science.gov (United States)

    Mendez, Dara D; Thorpe, Roland J; Amutah, Ndidi; Davis, Esa M; Walker, Renee E; Chapple-McGruder, Theresa; Bodnar, Lisa

    2016-12-01

    Studies of neighborhood racial composition or neighborhood poverty in association with pregnancy-related weight are limited. Prior studies of neighborhood racial density and poverty has been in association with adverse birth outcomes and suggest that neighborhoods with high rates of poverty and racial composition of black residents are typically segregated and systematically isolated from opportunities and resources. These neighborhood factors may help explain the racial disparities in pre-pregnancy weight and inadequate weight gain. This study examined whether neighborhood racial composition and neighborhood poverty was associated with weight before pregnancy and weight gain during pregnancy and if this association differed by race. We used vital birth records of singleton births of 73,061 non-Hispanic black and white women in Allegheny County, PA (2003-2010). Maternal race and ethnicity, pre-pregnancy body-mass-index (BMI), gestational weight gain and other individual-level characteristics were derived from vital birth record data, and measures of neighborhood racial composition (percentage of black residents in the neighborhood) and poverty (percentage of households in the neighborhood below the federal poverty) were derived using US Census data. Multilevel log binomial regression models were performed to estimate neighborhood racial composition and poverty in association with pre-pregnancy weight (i.e., overweight/obese) and gestational weight gain (i.e., inadequate and excessive). Black women as compared to white women were more likely to be overweight/obese before pregnancy and to have inadequate gestational weight gain (53.6% vs. 38.8%; 22.5% vs. 14.75 respectively). Black women living in predominately black neighborhoods were slightly more likely to be obese prior to pregnancy compared to black women living in predominately white neighborhoods (PR 1.10; 95% CI: 1.03, 1.16). Black and white women living in high poverty areas compared with women living in

  5. Weighted Feature Gaussian Kernel SVM for Emotion Recognition.

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    Wei, Wei; Jia, Qingxuan

    2016-01-01

    Emotion recognition with weighted feature based on facial expression is a challenging research topic and has attracted great attention in the past few years. This paper presents a novel method, utilizing subregion recognition rate to weight kernel function. First, we divide the facial expression image into some uniform subregions and calculate corresponding recognition rate and weight. Then, we get a weighted feature Gaussian kernel function and construct a classifier based on Support Vector Machine (SVM). At last, the experimental results suggest that the approach based on weighted feature Gaussian kernel function has good performance on the correct rate in emotion recognition. The experiments on the extended Cohn-Kanade (CK+) dataset show that our method has achieved encouraging recognition results compared to the state-of-the-art methods.

  6. Diffusion weighted imaging in patients with rectal cancer: Comparison between Gaussian and non-Gaussian models.

    Directory of Open Access Journals (Sweden)

    Georgios C Manikis

    Full Text Available The purpose of this study was to compare the performance of four diffusion models, including mono and bi-exponential both Gaussian and non-Gaussian models, in diffusion weighted imaging of rectal cancer.Nineteen patients with rectal adenocarcinoma underwent MRI examination of the rectum before chemoradiation therapy including a 7 b-value diffusion sequence (0, 25, 50, 100, 500, 1000 and 2000 s/mm2 at a 1.5T scanner. Four different diffusion models including mono- and bi-exponential Gaussian (MG and BG and non-Gaussian (MNG and BNG were applied on whole tumor volumes of interest. Two different statistical criteria were recruited to assess their fitting performance, including the adjusted-R2 and Root Mean Square Error (RMSE. To decide which model better characterizes rectal cancer, model selection was relied on Akaike Information Criteria (AIC and F-ratio.All candidate models achieved a good fitting performance with the two most complex models, the BG and the BNG, exhibiting the best fitting performance. However, both criteria for model selection indicated that the MG model performed better than any other model. In particular, using AIC Weights and F-ratio, the pixel-based analysis demonstrated that tumor areas better described by the simplest MG model in an average area of 53% and 33%, respectively. Non-Gaussian behavior was illustrated in an average area of 37% according to the F-ratio, and 7% using AIC Weights. However, the distributions of the pixels best fitted by each of the four models suggest that MG failed to perform better than any other model in all patients, and the overall tumor area.No single diffusion model evaluated herein could accurately describe rectal tumours. These findings probably can be explained on the basis of increased tumour heterogeneity, where areas with high vascularity could be fitted better with bi-exponential models, and areas with necrosis would mostly follow mono-exponential behavior.

  7. Transgenerational effect of neighborhood poverty on low birth weight among African Americans in Cook County, Illinois.

    Science.gov (United States)

    Collins, James W; David, Richard J; Rankin, Kristin M; Desireddi, Jennifer R

    2009-03-15

    In perinatal epidemiology, transgenerational risk factors are defined as conditions experienced by one generation that affect the pregnancy outcomes of the next generation. The authors investigated the transgenerational effect of neighborhood poverty on infant birth weight among African Americans. Stratified and multilevel logistic regression analyses were performed on an Illinois transgenerational data set with appended US Census income information. Singleton African-American infants (n = 40,648) born in 1989-1991 were considered index births. The mothers of index infants had been born in 1956-1976. The maternal grandmothers of index infants were identified. Rates of infant low birth weight (birth weight for maternal grandmother's residence in a poor neighborhood (compared with an affluent neighborhood) equaled 1.3 (95% confidence interval: 1.1, 1.4). This study suggests that maternal grandmother's exposure to neighborhood poverty during her pregnancy is a risk factor for infant low birth weight among African Americans.

  8. Advancing maternal age and infant birth weight among urban African Americans: the effect of neighborhood poverty.

    Science.gov (United States)

    Collins, James W; Simon, Dyan M; Jackson, Tara A; Drolet, Aimee

    2006-01-01

    This study sought to determine whether neighborhood poverty modifies the relationship between maternal age and infant birth weight among urban African Americans. Stratified analyses were performed on the vital records of African Americans born in Chicago by means of 1992-1995 computerized birth file with appended 1990 US Census income and 1995 Chicago Department of Public Health data. Four neighborhood-level variables (low median family income, high rates of unemployment, homicide, and lead poisoning) were analyzed. This is a population-based study. Twenty-one percent (n=21,811) of women resided in nonimpoverished neighborhoods (zero ecologic risk factors); 23% (n=24,914) of women lived in extremely impoverished neighborhoods (four ecologic risk factors). In nonimpoverished neighborhoods, 30-34 year old women had a moderately low birth weight (1500-2499 g) rate of 13.9% compared to 10.3% for women aged 20-24 years; risk difference (95% confidence interval [CI])=3.5 (2.2-4.6). In contrast, extremely impoverished women aged 30-34 years had a moderately low birth weight rate of 19.8% compared to 11.8% for women aged 20-24 years; risk difference (95% CI)=7.7 (6.1-9.3). This trend persisted among women who received early prenatal care and were primagravids or of low parity. Neighborhood poverty did not modify the association of advancing maternal age and the risk of very low birth weight (poverty accelerates the rise in moderately low birth weight but not very low birth weight; rates were associated with advancing maternal age among urban African Americans.

  9. Neighborhood Built and Social Environments and Change in Weight Status over the Summer in Low-Income Elementary School Children.

    Science.gov (United States)

    Miles, Rebecca; Wang, Yuxia; Johnson, Suzanne Bennett

    2018-05-31

    Neighborhoods can provide opportunities for children to maintain a healthy weight or encourage unhealthy weight gain. Which neighborhood characteristics matter most remains poorly understood. We investigated links between neighborhood characteristics and weight change over the summer in children from 12 elementary schools with a high proportion of children from low-income families, in a mid-sized city in the US South. Mixed models and objective measures of height and weight were used. Study participants were 2770 children (average age 8.3, range 5.6⁻12.6 years). Older and female children and those who were already overweight were more likely to gain weight over the summer compared to younger, male, and normal weight children. Overweight children who lived near 2 or more small grocery stores gained less weight than overweight children who lived near 0 (weight change, p = 0.0468; body mass index (BMI) change, p = 0.0209) or 1 store (weight change, p = 0.0136; BMI change, p = 0.0033). Normal weight children living in neighborhoods with more large multifamily buildings gained more weight over the summer, although this association only approached significance. Additional efforts to understand which neighborhood factors have greater significance for overweight compared to normal weight children are warranted.

  10. Poisson and Gaussian approximation of weighted local empirical processes

    NARCIS (Netherlands)

    Einmahl, J.H.J.

    1995-01-01

    We consider the local empirical process indexed by sets, a greatly generalized version of the well-studied uniform tail empirical process. We show that the weak limit of weighted versions of this process is Poisson under certain conditions, whereas it is Gaussian in other situations. Our main

  11. Race, Age, and Neighborhood Socioeconomic Status in Low Birth Weight Disparities Among Adolescent Mothers: An Intersectional Inquiry.

    Science.gov (United States)

    Coley, Sheryl L; Nichols, Tracy R

    2016-01-01

    Few studies examined socioeconomic contributors to racial disparities in low birth weight outcomes between African-American and Caucasian adolescent mothers. This cross-sectional study examined the intersections of maternal racial status, age, and neighborhood socioeconomic status in explaining these disparities in low birth weight outcomes across a statewide sample of adolescent mothers. Using data from the North Carolina State Center of Health Statistics for 2010-2011, birth cases for 16,472 adolescents were geocoded by street address and linked to census-tract information from the 2010 United States Census. Multilevel models with interaction terms were used to identify significant associations between maternal racial status, age, and neighborhood socioeconomic status (as defined by census-tract median household income) and low birth weight outcomes across census tracts. Significant racial differences were identified in which African-American adolescents had greater odds of low birth weight outcomes than Caucasian adolescents (OR=1.88, 95% CI 1.64, 2.15). Although racial disparities in low birth weight outcomes remained significant in context of maternal age and neighborhood socioeconomic status, the greatest disparities were found between African-American and Caucasian adolescents that lived in areas of higher socioeconomic status (psocioeconomic status. Further investigations using intersectional frameworks are needed for examining the relationships between neighborhood socioeconomic status and birth outcome disparities among infants born to adolescent mothers.

  12. From neighborhood design and food options to residents' weight status.

    Science.gov (United States)

    Cerin, Ester; Frank, Lawrence D; Sallis, James F; Saelens, Brian E; Conway, Terry L; Chapman, James E; Glanz, Karen

    2011-06-01

    This study examined associations of accessibility, availability, price, and quality of food choices and neighborhood urban design with weight status and utilitarian walking. To account for self-selection bias, data on adult residents of a middle-to-high-income neighborhood were used. Participants kept a 2-day activity/travel diary and self-reported socio-demographics, height, and weight. Geographic Information Systems data were used to objectively quantify walking-related aspects of urban design, and number of and distance to food outlets within respondents' 1km residential buffers. Food outlets were audited for availability, price, and quality of healthful food choices. Number of convenience stores and in-store healthful food choices were positively related to walking for errands which, in turn, was predictive of lower risk of being overweight/obese. Negative associations with overweight/obesity unexplained by walking were found for number of grocery stores and healthful food choices in sit-down restaurants. Aspects of urban form and food environment were associated with walking for eating purposes which, however, was not predictive of overweight/obesity. Access to diverse destinations, food outlets and healthful food choices may promote pedestrian activity and contribute to better weight regulation. Accessibility and availability of healthful food choices may lower the risk of overweight/obesity by providing opportunities for healthier dietary patterns. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Comparison of non-Gaussian and Gaussian diffusion models of diffusion weighted imaging of rectal cancer at 3.0 T MRI.

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    Zhang, Guangwen; Wang, Shuangshuang; Wen, Didi; Zhang, Jing; Wei, Xiaocheng; Ma, Wanling; Zhao, Weiwei; Wang, Mian; Wu, Guosheng; Zhang, Jinsong

    2016-12-09

    Water molecular diffusion in vivo tissue is much more complicated. We aimed to compare non-Gaussian diffusion models of diffusion-weighted imaging (DWI) including intra-voxel incoherent motion (IVIM), stretched-exponential model (SEM) and Gaussian diffusion model at 3.0 T MRI in patients with rectal cancer, and to determine the optimal model for investigating the water diffusion properties and characterization of rectal carcinoma. Fifty-nine consecutive patients with pathologically confirmed rectal adenocarcinoma underwent DWI with 16 b-values at a 3.0 T MRI system. DWI signals were fitted to the mono-exponential and non-Gaussian diffusion models (IVIM-mono, IVIM-bi and SEM) on primary tumor and adjacent normal rectal tissue. Parameters of standard apparent diffusion coefficient (ADC), slow- and fast-ADC, fraction of fast ADC (f), α value and distributed diffusion coefficient (DDC) were generated and compared between the tumor and normal tissues. The SEM exhibited the best fitting results of actual DWI signal in rectal cancer and the normal rectal wall (R 2  = 0.998, 0.999 respectively). The DDC achieved relatively high area under the curve (AUC = 0.980) in differentiating tumor from normal rectal wall. Non-Gaussian diffusion models could assess tissue properties more accurately than the ADC derived Gaussian diffusion model. SEM may be used as a potential optimal model for characterization of rectal cancer.

  14. Relationship between neighborhood disadvantage and social function of Wisconsin 2- and 3-year-olds born at very low birth weight.

    Science.gov (United States)

    McManus, Beth Marie; Robert, Stephanie A; Albanese, Aggie; Sadek-Badawi, Mona; Palta, Mari

    2011-02-01

    To examine whether (1) neighborhood disadvantage is associated with social function in 2- and 3-year-olds born at very low birth weight (<1500 g) and (2) the association between social function and child's health-related quality of life (HRQoL) is moderated by neighborhood disadvantage. Cross-sectional study using the Newborn Lung Project, a cohort of infants born at very low birth weight in 2003 and 2004 in Wisconsin. Wisconsin. This study includes the subgroup of 626 non-Hispanic black or white infants who were followed up at ages 24 to 43 months with parent-reported health and developmental information. An index of neighborhood disadvantage was derived by principal component analysis of 5 census tract variables (percentage of families in poverty, percentage of households with income higher than the state median, percentage of women with bachelor's degree or more, percentage of single mothers, and percentage of mothers of young children unemployed). Children were then classified (based on index tertiles) as living in either disadvantaged, middle advantage, or advantaged neighborhoods. Children's HRQoL was measured using the Pediatric Quality of Life Inventory. Social function was measured using the Pediatric Evaluation of Disability Inventory. Adjusting for child medical and family socioeconomic attributes, social function was lower (mean difference, -4.60; 95% confidence interval, -8.4 to -0.8) for children living in disadvantaged vs advantaged neighborhoods. We also found that the ill effects of lower HRQoL are particularly bad for children living in a disadvantaged neighborhood. Children born at very low birth weight have disparities in social function at ages 2 and 3 years that are associated with both HRQoL and neighborhood characteristics.

  15. Automatic segmentation of myocardium from black-blood MR images using entropy and local neighborhood information.

    Directory of Open Access Journals (Sweden)

    Qian Zheng

    Full Text Available By using entropy and local neighborhood information, we present in this study a robust adaptive Gaussian regularizing Chan-Vese (CV model to segment the myocardium from magnetic resonance images with intensity inhomogeneity. By utilizing the circular Hough transformation (CHT our model is able to detect epicardial and endocardial contours of the left ventricle (LV as circles automatically, and the circles are used as the initialization. In the cost functional of our model, the interior and exterior energies are weighted by the entropy to improve the robustness of the evolving curve. Local neighborhood information is used to evolve the level set function to reduce the impact of the heterogeneity inside the regions and to improve the segmentation accuracy. An adaptive window is utilized to reduce the sensitivity to initialization. The Gaussian kernel is used to regularize the level set function, which can not only ensure the smoothness and stability of the level set function, but also eliminate the traditional Euclidean length term and re-initialization. Extensive validation of the proposed method on patient data demonstrates its superior performance over other state-of-the-art methods.

  16. Phase statistics in non-Gaussian scattering

    International Nuclear Information System (INIS)

    Watson, Stephen M; Jakeman, Eric; Ridley, Kevin D

    2006-01-01

    Amplitude weighting can improve the accuracy of frequency measurements in signals corrupted by multiplicative speckle noise. When the speckle field constitutes a circular complex Gaussian process, the optimal function of amplitude weighting is provided by the field intensity, corresponding to the intensity-weighted phase derivative statistic. In this paper, we investigate the phase derivative and intensity-weighted phase derivative returned from a two-dimensional random walk, which constitutes a generic scattering model capable of producing both Gaussian and non-Gaussian fluctuations. Analytical results are developed for the correlation properties of the intensity-weighted phase derivative, as well as limiting probability densities of the scattered field. Numerical simulation is used to generate further probability densities and determine optimal weighting criteria from non-Gaussian fields. The results are relevant to frequency retrieval in radiation scattered from random media

  17. Parameter estimation and statistical test of geographically weighted bivariate Poisson inverse Gaussian regression models

    Science.gov (United States)

    Amalia, Junita; Purhadi, Otok, Bambang Widjanarko

    2017-11-01

    Poisson distribution is a discrete distribution with count data as the random variables and it has one parameter defines both mean and variance. Poisson regression assumes mean and variance should be same (equidispersion). Nonetheless, some case of the count data unsatisfied this assumption because variance exceeds mean (over-dispersion). The ignorance of over-dispersion causes underestimates in standard error. Furthermore, it causes incorrect decision in the statistical test. Previously, paired count data has a correlation and it has bivariate Poisson distribution. If there is over-dispersion, modeling paired count data is not sufficient with simple bivariate Poisson regression. Bivariate Poisson Inverse Gaussian Regression (BPIGR) model is mix Poisson regression for modeling paired count data within over-dispersion. BPIGR model produces a global model for all locations. In another hand, each location has different geographic conditions, social, cultural and economic so that Geographically Weighted Regression (GWR) is needed. The weighting function of each location in GWR generates a different local model. Geographically Weighted Bivariate Poisson Inverse Gaussian Regression (GWBPIGR) model is used to solve over-dispersion and to generate local models. Parameter estimation of GWBPIGR model obtained by Maximum Likelihood Estimation (MLE) method. Meanwhile, hypothesis testing of GWBPIGR model acquired by Maximum Likelihood Ratio Test (MLRT) method.

  18. Workplace Neighborhoods, Walking, Physical Activity, Weight Status, and Perceived Health

    OpenAIRE

    Forsyth, Ann; Oakes, J.

    2014-01-01

    Recent interest has focused on how the built environment in residential neighborhoods affects walking and other physical activity. The neighborhood around the workplace has been examined far less. This study explored the neighborhood around the workplace and its correlation with the amount of walking, level of physical activity, body mass index, and perceived health of those who (a) worked away from home (N = 446) and (b) were retired or unemployed (N = 207). Study participants were recruited...

  19. Aperture correction with an asymmetrically trimmed gaussian weight in SPECT with a fan-beam collimator

    International Nuclear Information System (INIS)

    Kamiya, Ryo; Ogawa, Koichi

    2013-01-01

    The aim of the study is to improve the spatial resolution of single photon emission computed tomography (SPECT) images acquired with a fan-beam collimator. The aperture angle of a hole in the fan-beam collimator depends on the position of the collimator. To correct the aperture effect in an iterative image reconstruction, an asymmetrically trimmed Gaussian weight was used for a model. To confirm the validity of our method, point source phantoms and brain phantom were used in the simulation, and we applied the method to the clinical data. The results of the simulation showed that the spatial resolution of point sources improved from about 6 to 2 pixels full width at half maximum, and the corrected point sources were isotropic. The results of the simulation with the brain phantom showed that our proposed method could improve the spatial resolution of the phantom, and our method was effective for different fan-beam collimators with different focal lengths. The results of clinical data showed that the quality of the reconstructed image was improved with our proposed method. Our proposed aperture correction method with the asymmetrically trimmed Gaussian weighting function was effective in improving the spatial resolution of SPECT images acquired with the fan-beam collimator. (author)

  20. Neighborhood built environment and socioeconomic status in relation to physical activity, sedentary behavior, and weight status of adolescents.

    Science.gov (United States)

    Sallis, James F; Conway, Terry L; Cain, Kelli L; Carlson, Jordan A; Frank, Lawrence D; Kerr, Jacqueline; Glanz, Karen; Chapman, James E; Saelens, Brian E

    2018-05-01

    The study examined the association of neighborhood walkability to multiple activity-related outcomes and BMI among adolescents and evaluated socioeconomic status as an effect modifier. Cross-sectional study, with adolescents recruited from neighborhoods that met criteria for a 2 × 2 matrix defined by high/low GIS-defined walkability and high/low median income. Adolescents aged 12-16 years (n = 928) were recruited from selected neighborhoods in Maryland and King County, Washington regions in 2009-2011. There were 50.4% girls, and 66.3% were non-Hispanic white, with no medical restrictions on physical activity (PA) or diets. Total PA and sedentary time was assessed by 7 days of accelerometer monitoring. Adolescents self-reported active transport, time spent on 6 sedentary behaviors, and height and weight, used to compute BMI percentiles. Mixed model linear and logistic regressions examined outcomes for association with walkability and income, adjusting for demographic covariates and clustering within block groups. Walkability was positively and significantly related to objectively-measured PA (p < .001) and more frequent walking for transportation (p < .001). Total self-reported sedentary time (p = .048) and TV time (p < .007) were negatively related to walkability. Time in vehicles was negatively related to walkability only among higher-income adolescents. Neighborhood walkability was strongly and consistently associated with adolescents' objectively-assessed total physical activity and reported active transportation. A novel finding was that adolescents living in walkable neighborhoods reported less television time and less time in vehicles. Most results were similar across income categories. Results strengthen the rationale for recommendations to improve walkability. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. The association of neighborhood social capital and ethnic (minority) density with pregnancy outcomes in the Netherlands.

    Science.gov (United States)

    Schölmerich, Vera L N; Erdem, Özcan; Borsboom, Gerard; Ghorashi, Halleh; Groenewegen, Peter; Steegers, Eric A P; Kawachi, Ichiro; Denktaş, Semiha

    2014-01-01

    Perinatal morbidity rates are relatively high in the Netherlands, and significant inequalities in perinatal morbidity and mortality can be found across neighborhoods. In socioeconomically deprived areas, 'Western' women are particularly at risk for adverse birth outcomes. Almost all studies to date have explained the disparities in terms of individual determinants of birth outcomes. This study examines the influence of neighborhood contextual characteristics on birth weight (adjusted for gestational age) and preterm birth. We focused on the influence of neighborhood social capital--measured as informal socializing and social connections between neighbors--as well as ethnic (minority) density. Data on birth weight and prematurity were obtained from the Perinatal Registration Netherlands 2000-2008 dataset, containing 97% of all pregnancies. Neighborhood-level measurements were obtained from three different sources, comprising both survey and registration data. We included 3.422 neighborhoods and 1.527.565 pregnancies for the birth weight analysis and 1.549.285 pregnancies for the premature birth analysis. Linear and logistic multilevel regression was performed to assess the associations of individual and neighborhood level variables with birth weight and preterm birth. We found modest but significant neighborhood effects on birth weight and preterm births. The effect of ethnic (minority) density was stronger than that of neighborhood social capital. Moreover, ethnic (minority) density was associated with higher birth weight for infants of non-Western ethnic minority women compared to Western women (15 grams; 95% CI: 12,4/17,5) as well as reduced risk for prematurity (OR 0.97; CI 0,95/0,99). Our results indicate that neighborhood contexts are associated with birth weight and preterm birth in the Netherlands. Moreover, ethnic (minority) density seems to be a protective factor for non-Western ethnic minority women, but not for Western women. This helps explain the

  2. The neighborhood environment and obesity: Understanding variation by race/ethnicity.

    Science.gov (United States)

    Wong, Michelle S; Chan, Kitty S; Jones-Smith, Jessica C; Colantuoni, Elizabeth; Thorpe, Roland J; Bleich, Sara N

    2018-06-01

    Neighborhood characteristics have been associated with obesity, but less is known whether relationships vary by race/ethnicity. This study examined the relationship between soda consumption - a behavior strongly associated with obesity - and weight status with neighborhood sociodemographic, social, and built environments by race/ethnicity. We merged data on adults from the 2011-2013 California Health Interview Survey, U.S. Census data, and InfoUSA (n=62,396). Dependent variables were soda consumption and weight status outcomes (body mass index and obesity status). Main independent variables were measures of three neighborhood environments: social (social cohesion and safety), sociodemographic (neighborhood socioeconomic status, educational attainment, percent Asian, percent Hispanic, and percent black), and built environments (number of grocery stores, convenience stores, fast food restaurants, and gyms in neighborhood). We fit multi-level linear and logistic regression models, stratified by individual race/ethnicity (NH (non-Hispanic) Whites, NH African Americans, Hispanics, and NH Asians) controlling for individual-level characteristics, to estimate neighborhood contextual effects on study outcomes. Lower neighborhood educational attainment was associated with higher odds of obesity and soda consumption in all racial/ethnic groups. We found fewer associations between study outcomes and the neighborhood, especially the built environment, among NH African Americans and NH Asians. While improvements to neighborhood environment may be promising to reduce obesity, null associations among minority subgroups suggest that changes, particularly to the built environment, may alone be insufficient to address obesity in these groups. Published by Elsevier Inc.

  3. Gaussian likelihood inference on data from trans-Gaussian random fields with Matérn covariance function

    KAUST Repository

    Yan, Yuan; Genton, Marc G.

    2017-01-01

    Gaussian likelihood inference has been studied and used extensively in both statistical theory and applications due to its simplicity. However, in practice, the assumption of Gaussianity is rarely met in the analysis of spatial data. In this paper, we study the effect of non-Gaussianity on Gaussian likelihood inference for the parameters of the Matérn covariance model. By using Monte Carlo simulations, we generate spatial data from a Tukey g-and-h random field, a flexible trans-Gaussian random field, with the Matérn covariance function, where g controls skewness and h controls tail heaviness. We use maximum likelihood based on the multivariate Gaussian distribution to estimate the parameters of the Matérn covariance function. We illustrate the effects of non-Gaussianity of the data on the estimated covariance function by means of functional boxplots. Thanks to our tailored simulation design, a comparison of the maximum likelihood estimator under both the increasing and fixed domain asymptotics for spatial data is performed. We find that the maximum likelihood estimator based on Gaussian likelihood is overall satisfying and preferable than the non-distribution-based weighted least squares estimator for data from the Tukey g-and-h random field. We also present the result for Gaussian kriging based on Matérn covariance estimates with data from the Tukey g-and-h random field and observe an overall satisfactory performance.

  4. Gaussian likelihood inference on data from trans-Gaussian random fields with Matérn covariance function

    KAUST Repository

    Yan, Yuan

    2017-07-13

    Gaussian likelihood inference has been studied and used extensively in both statistical theory and applications due to its simplicity. However, in practice, the assumption of Gaussianity is rarely met in the analysis of spatial data. In this paper, we study the effect of non-Gaussianity on Gaussian likelihood inference for the parameters of the Matérn covariance model. By using Monte Carlo simulations, we generate spatial data from a Tukey g-and-h random field, a flexible trans-Gaussian random field, with the Matérn covariance function, where g controls skewness and h controls tail heaviness. We use maximum likelihood based on the multivariate Gaussian distribution to estimate the parameters of the Matérn covariance function. We illustrate the effects of non-Gaussianity of the data on the estimated covariance function by means of functional boxplots. Thanks to our tailored simulation design, a comparison of the maximum likelihood estimator under both the increasing and fixed domain asymptotics for spatial data is performed. We find that the maximum likelihood estimator based on Gaussian likelihood is overall satisfying and preferable than the non-distribution-based weighted least squares estimator for data from the Tukey g-and-h random field. We also present the result for Gaussian kriging based on Matérn covariance estimates with data from the Tukey g-and-h random field and observe an overall satisfactory performance.

  5. The Association of Neighborhood Social Capital and Ethnic (Minority) Density with Pregnancy Outcomes in the Netherlands

    Science.gov (United States)

    Schölmerich, Vera L. N.; Erdem, Özcan; Borsboom, Gerard; Ghorashi, Halleh; Groenewegen, Peter; Steegers, Eric A. P.; Kawachi, Ichiro; Denktaş, Semiha

    2014-01-01

    Background Perinatal morbidity rates are relatively high in the Netherlands, and significant inequalities in perinatal morbidity and mortality can be found across neighborhoods. In socioeconomically deprived areas, ‘Western’ women are particularly at risk for adverse birth outcomes. Almost all studies to date have explained the disparities in terms of individual determinants of birth outcomes. This study examines the influence of neighborhood contextual characteristics on birth weight (adjusted for gestational age) and preterm birth. We focused on the influence of neighborhood social capital – measured as informal socializing and social connections between neighbors – as well as ethnic (minority) density. Methods Data on birth weight and prematurity were obtained from the Perinatal Registration Netherlands 2000–2008 dataset, containing 97% of all pregnancies. Neighborhood-level measurements were obtained from three different sources, comprising both survey and registration data. We included 3.422 neighborhoods and 1.527.565 pregnancies for the birth weight analysis and 1.549.285 pregnancies for the premature birth analysis. Linear and logistic multilevel regression was performed to assess the associations of individual and neighborhood level variables with birth weight and preterm birth. Results We found modest but significant neighborhood effects on birth weight and preterm births. The effect of ethnic (minority) density was stronger than that of neighborhood social capital. Moreover, ethnic (minority) density was associated with higher birth weight for infants of non-Western ethnic minority women compared to Western women (15 grams; 95% CI: 12,4/17,5) as well as reduced risk for prematurity (OR 0.97; CI 0,95/0,99). Conclusions Our results indicate that neighborhood contexts are associated with birth weight and preterm birth in the Netherlands. Moreover, ethnic (minority) density seems to be a protective factor for non-Western ethnic minority women, but

  6. The association of neighborhood social capital and ethnic (minority density with pregnancy outcomes in the Netherlands.

    Directory of Open Access Journals (Sweden)

    Vera L N Schölmerich

    Full Text Available BACKGROUND: Perinatal morbidity rates are relatively high in the Netherlands, and significant inequalities in perinatal morbidity and mortality can be found across neighborhoods. In socioeconomically deprived areas, 'Western' women are particularly at risk for adverse birth outcomes. Almost all studies to date have explained the disparities in terms of individual determinants of birth outcomes. This study examines the influence of neighborhood contextual characteristics on birth weight (adjusted for gestational age and preterm birth. We focused on the influence of neighborhood social capital--measured as informal socializing and social connections between neighbors--as well as ethnic (minority density. METHODS: Data on birth weight and prematurity were obtained from the Perinatal Registration Netherlands 2000-2008 dataset, containing 97% of all pregnancies. Neighborhood-level measurements were obtained from three different sources, comprising both survey and registration data. We included 3.422 neighborhoods and 1.527.565 pregnancies for the birth weight analysis and 1.549.285 pregnancies for the premature birth analysis. Linear and logistic multilevel regression was performed to assess the associations of individual and neighborhood level variables with birth weight and preterm birth. RESULTS: We found modest but significant neighborhood effects on birth weight and preterm births. The effect of ethnic (minority density was stronger than that of neighborhood social capital. Moreover, ethnic (minority density was associated with higher birth weight for infants of non-Western ethnic minority women compared to Western women (15 grams; 95% CI: 12,4/17,5 as well as reduced risk for prematurity (OR 0.97; CI 0,95/0,99. CONCLUSIONS: Our results indicate that neighborhood contexts are associated with birth weight and preterm birth in the Netherlands. Moreover, ethnic (minority density seems to be a protective factor for non-Western ethnic minority women

  7. Multi-Gaussian fitting for pulse waveform using Weighted Least Squares and multi-criteria decision making method.

    Science.gov (United States)

    Wang, Lu; Xu, Lisheng; Feng, Shuting; Meng, Max Q-H; Wang, Kuanquan

    2013-11-01

    Analysis of pulse waveform is a low cost, non-invasive method for obtaining vital information related to the conditions of the cardiovascular system. In recent years, different Pulse Decomposition Analysis (PDA) methods have been applied to disclose the pathological mechanisms of the pulse waveform. All these methods decompose single-period pulse waveform into a constant number (such as 3, 4 or 5) of individual waves. Furthermore, those methods do not pay much attention to the estimation error of the key points in the pulse waveform. The estimation of human vascular conditions depends on the key points' positions of pulse wave. In this paper, we propose a Multi-Gaussian (MG) model to fit real pulse waveforms using an adaptive number (4 or 5 in our study) of Gaussian waves. The unknown parameters in the MG model are estimated by the Weighted Least Squares (WLS) method and the optimized weight values corresponding to different sampling points are selected by using the Multi-Criteria Decision Making (MCDM) method. Performance of the MG model and the WLS method has been evaluated by fitting 150 real pulse waveforms of five different types. The resulting Normalized Root Mean Square Error (NRMSE) was less than 2.0% and the estimation accuracy for the key points was satisfactory, demonstrating that our proposed method is effective in compressing, synthesizing and analyzing pulse waveforms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Neighborhood Social Predictors of Weight-related Measures in Underserved African Americans in the PATH Trial.

    Science.gov (United States)

    McDaniel, Tyler C; Wilson, Dawn K; Coulon, Sandra M; Hand, Gregory A; Siceloff, E Rebekah

    2015-11-05

    African Americans have the highest rate of obesity in the United States relative to other ethnic minority groups. Bioecological factors including neighborhood social and physical environmental variables may be important predictors of weight-related measures specifically body mass index (BMI) in African American adults. Baseline data from the Positive Action for Today's Health (PATH) trial were collected from 417 African American adults. Overall a multiple regression model for BMI was significant, showing positive associations with average daily moderate-to-vigorous physical activity (MVPA) (B =-.21, Psocial interaction (B =-.13, Psocial interaction was associated with healthier BMI, highlighting it as a potential critical factor for future interventions in underserved, African American communities.

  9. Neighborhood Walkability and Body Mass Index Trajectories: Longitudinal Study of Canadians.

    Science.gov (United States)

    Wasfi, Rania A; Dasgupta, Kaberi; Orpana, Heather; Ross, Nancy A

    2016-05-01

    To assess the impact of neighborhood walkability on body mass index (BMI) trajectories of urban Canadians. Data are from Canada's National Population Health Survey (n = 2935; biannual assessments 1994-2006). We measured walkability with the Walk Score. We modeled body mass index (BMI, defined as weight in kilograms divided by the square of height in meters [kg/m(2)]) trajectories as a function of Walk Score and sociodemographic and behavioral covariates with growth curve models and fixed-effects regression models. In men, BMI increased annually by an average of 0.13 kg/m(2) (95% confidence interval [CI] = 0.11, 0.14) over the 12 years of follow-up. Moving to a high-walkable neighborhood (2 or more Walk Score quartiles higher) decreased BMI trajectories for men by approximately 1 kg/m(2) (95% CI = -1.16, -0.17). Moving to a low-walkable neighborhood increased BMI for men by approximately 0.45 kg/m(2) (95% CI = 0.01, 0.89). There was no detectable influence of neighborhood walkability on body weight for women. Our study of a large sample of urban Canadians followed for 12 years confirms that neighborhood walkability influences BMI trajectories for men, and may be influential in curtailing male age-related weight gain.

  10. Rapid construction of pinhole SPECT system matrices by distance-weighted Gaussian interpolation method combined with geometric parameter estimations

    International Nuclear Information System (INIS)

    Lee, Ming-Wei; Chen, Yi-Chun

    2014-01-01

    In pinhole SPECT applied to small-animal studies, it is essential to have an accurate imaging system matrix, called H matrix, for high-spatial-resolution image reconstructions. Generally, an H matrix can be obtained by various methods, such as measurements, simulations or some combinations of both methods. In this study, a distance-weighted Gaussian interpolation method combined with geometric parameter estimations (DW-GIMGPE) is proposed. It utilizes a simplified grid-scan experiment on selected voxels and parameterizes the measured point response functions (PRFs) into 2D Gaussians. The PRFs of missing voxels are interpolated by the relations between the Gaussian coefficients and the geometric parameters of the imaging system with distance-weighting factors. The weighting factors are related to the projected centroids of voxels on the detector plane. A full H matrix is constructed by combining the measured and interpolated PRFs of all voxels. The PRFs estimated by DW-GIMGPE showed similar profiles as the measured PRFs. OSEM reconstructed images of a hot-rod phantom and normal rat myocardium demonstrated the effectiveness of the proposed method. The detectability of a SKE/BKE task on a synthetic spherical test object verified that the constructed H matrix provided comparable detectability to that of the H matrix acquired by a full 3D grid-scan experiment. The reduction in the acquisition time of a full 1.0-mm grid H matrix was about 15.2 and 62.2 times with the simplified grid pattern on 2.0-mm and 4.0-mm grid, respectively. A finer-grid H matrix down to 0.5-mm spacing interpolated by the proposed method would shorten the acquisition time by 8 times, additionally. -- Highlights: • A rapid interpolation method of system matrices (H) is proposed, named DW-GIMGPE. • Reduce H acquisition time by 15.2× with simplified grid scan and 2× interpolation. • Reconstructions of a hot-rod phantom with measured and DW-GIMGPE H were similar. • The imaging study of normal

  11. An Efficient Seam Elimination Method for UAV Images Based on Wallis Dodging and Gaussian Distance Weight Enhancement.

    Science.gov (United States)

    Tian, Jinyan; Li, Xiaojuan; Duan, Fuzhou; Wang, Junqian; Ou, Yang

    2016-05-10

    The rapid development of Unmanned Aerial Vehicle (UAV) remote sensing conforms to the increasing demand for the low-altitude very high resolution (VHR) image data. However, high processing speed of massive UAV data has become an indispensable prerequisite for its applications in various industry sectors. In this paper, we developed an effective and efficient seam elimination approach for UAV images based on Wallis dodging and Gaussian distance weight enhancement (WD-GDWE). The method encompasses two major steps: first, Wallis dodging was introduced to adjust the difference of brightness between the two matched images, and the parameters in the algorithm were derived in this study. Second, a Gaussian distance weight distribution method was proposed to fuse the two matched images in the overlap region based on the theory of the First Law of Geography, which can share the partial dislocation in the seam to the whole overlap region with an effect of smooth transition. This method was validated at a study site located in Hanwang (Sichuan, China) which was a seriously damaged area in the 12 May 2008 enchuan Earthquake. Then, a performance comparison between WD-GDWE and the other five classical seam elimination algorithms in the aspect of efficiency and effectiveness was conducted. Results showed that WD-GDWE is not only efficient, but also has a satisfactory effectiveness. This method is promising in advancing the applications in UAV industry especially in emergency situations.

  12. NEIGHBORHOOD CHOICE AND NEIGHBORHOOD CHANGE

    OpenAIRE

    Bruch, Elizabeth; Mare, Robert D.

    2006-01-01

    This paper examines the relationships between the residential choices of individuals and aggregate patterns of neighborhood change. We investigate the conditions under which individuals’ preferences for the race-ethnic composition of their neighborhoods produce high levels of segregation. Using computational models, we find that high levels of segregation occur only when individuals’ preferences follow a threshold function. If individuals make finer-grained distinctions among neighborhoods th...

  13. Voxel-Based Neighborhood for Spatial Shape Pattern Classification of Lidar Point Clouds with Supervised Learning

    Directory of Open Access Journals (Sweden)

    Victoria Plaza-Leiva

    2017-03-01

    Full Text Available Improving the effectiveness of spatial shape features classification from 3D lidar data is very relevant because it is largely used as a fundamental step towards higher level scene understanding challenges of autonomous vehicles and terrestrial robots. In this sense, computing neighborhood for points in dense scans becomes a costly process for both training and classification. This paper proposes a new general framework for implementing and comparing different supervised learning classifiers with a simple voxel-based neighborhood computation where points in each non-overlapping voxel in a regular grid are assigned to the same class by considering features within a support region defined by the voxel itself. The contribution provides offline training and online classification procedures as well as five alternative feature vector definitions based on principal component analysis for scatter, tubular and planar shapes. Moreover, the feasibility of this approach is evaluated by implementing a neural network (NN method previously proposed by the authors as well as three other supervised learning classifiers found in scene processing methods: support vector machines (SVM, Gaussian processes (GP, and Gaussian mixture models (GMM. A comparative performance analysis is presented using real point clouds from both natural and urban environments and two different 3D rangefinders (a tilting Hokuyo UTM-30LX and a Riegl. Classification performance metrics and processing time measurements confirm the benefits of the NN classifier and the feasibility of voxel-based neighborhood.

  14. Voxel-Based Neighborhood for Spatial Shape Pattern Classification of Lidar Point Clouds with Supervised Learning.

    Science.gov (United States)

    Plaza-Leiva, Victoria; Gomez-Ruiz, Jose Antonio; Mandow, Anthony; García-Cerezo, Alfonso

    2017-03-15

    Improving the effectiveness of spatial shape features classification from 3D lidar data is very relevant because it is largely used as a fundamental step towards higher level scene understanding challenges of autonomous vehicles and terrestrial robots. In this sense, computing neighborhood for points in dense scans becomes a costly process for both training and classification. This paper proposes a new general framework for implementing and comparing different supervised learning classifiers with a simple voxel-based neighborhood computation where points in each non-overlapping voxel in a regular grid are assigned to the same class by considering features within a support region defined by the voxel itself. The contribution provides offline training and online classification procedures as well as five alternative feature vector definitions based on principal component analysis for scatter, tubular and planar shapes. Moreover, the feasibility of this approach is evaluated by implementing a neural network (NN) method previously proposed by the authors as well as three other supervised learning classifiers found in scene processing methods: support vector machines (SVM), Gaussian processes (GP), and Gaussian mixture models (GMM). A comparative performance analysis is presented using real point clouds from both natural and urban environments and two different 3D rangefinders (a tilting Hokuyo UTM-30LX and a Riegl). Classification performance metrics and processing time measurements confirm the benefits of the NN classifier and the feasibility of voxel-based neighborhood.

  15. Quantum Teamwork for Unconditional Multiparty Communication with Gaussian States

    Science.gov (United States)

    Zhang, Jing; Adesso, Gerardo; Xie, Changde; Peng, Kunchi

    2009-08-01

    We demonstrate the capability of continuous variable Gaussian states to communicate multipartite quantum information. A quantum teamwork protocol is presented according to which an arbitrary possibly entangled multimode state can be faithfully teleported between two teams each comprising many cooperative users. We prove that N-mode Gaussian weighted graph states exist for arbitrary N that enable unconditional quantum teamwork implementations for any arrangement of the teams. These perfect continuous variable maximally multipartite entangled resources are typical among pure Gaussian states and are unaffected by the entanglement frustration occurring in multiqubit states.

  16. A Gaussian mixture copula model based localized Gaussian process regression approach for long-term wind speed prediction

    International Nuclear Information System (INIS)

    Yu, Jie; Chen, Kuilin; Mori, Junichi; Rashid, Mudassir M.

    2013-01-01

    Optimizing wind power generation and controlling the operation of wind turbines to efficiently harness the renewable wind energy is a challenging task due to the intermittency and unpredictable nature of wind speed, which has significant influence on wind power production. A new approach for long-term wind speed forecasting is developed in this study by integrating GMCM (Gaussian mixture copula model) and localized GPR (Gaussian process regression). The time series of wind speed is first classified into multiple non-Gaussian components through the Gaussian mixture copula model and then Bayesian inference strategy is employed to incorporate the various non-Gaussian components using the posterior probabilities. Further, the localized Gaussian process regression models corresponding to different non-Gaussian components are built to characterize the stochastic uncertainty and non-stationary seasonality of the wind speed data. The various localized GPR models are integrated through the posterior probabilities as the weightings so that a global predictive model is developed for the prediction of wind speed. The proposed GMCM–GPR approach is demonstrated using wind speed data from various wind farm locations and compared against the GMCM-based ARIMA (auto-regressive integrated moving average) and SVR (support vector regression) methods. In contrast to GMCM–ARIMA and GMCM–SVR methods, the proposed GMCM–GPR model is able to well characterize the multi-seasonality and uncertainty of wind speed series for accurate long-term prediction. - Highlights: • A novel predictive modeling method is proposed for long-term wind speed forecasting. • Gaussian mixture copula model is estimated to characterize the multi-seasonality. • Localized Gaussian process regression models can deal with the random uncertainty. • Multiple GPR models are integrated through Bayesian inference strategy. • The proposed approach shows higher prediction accuracy and reliability

  17. Nonclassicality by Local Gaussian Unitary Operations for Gaussian States

    Directory of Open Access Journals (Sweden)

    Yangyang Wang

    2018-04-01

    Full Text Available A measure of nonclassicality N in terms of local Gaussian unitary operations for bipartite Gaussian states is introduced. N is a faithful quantum correlation measure for Gaussian states as product states have no such correlation and every non product Gaussian state contains it. For any bipartite Gaussian state ρ A B , we always have 0 ≤ N ( ρ A B < 1 , where the upper bound 1 is sharp. An explicit formula of N for ( 1 + 1 -mode Gaussian states and an estimate of N for ( n + m -mode Gaussian states are presented. A criterion of entanglement is established in terms of this correlation. The quantum correlation N is also compared with entanglement, Gaussian discord and Gaussian geometric discord.

  18. Association between neighborhood need and spatial access to food stores and fast food restaurants in neighborhoods of colonias.

    Science.gov (United States)

    Sharkey, Joseph R; Horel, Scott; Han, Daikwon; Huber, John C

    2009-02-16

    To determine the extent to which neighborhood needs (socioeconomic deprivation and vehicle availability) are associated with two criteria of food environment access: 1) distance to the nearest food store and fast food restaurant and 2) coverage (number) of food stores and fast food restaurants within a specified network distance of neighborhood areas of colonias, using ground-truthed methods. Data included locational points for 315 food stores and 204 fast food restaurants, and neighborhood characteristics from the 2000 U.S. Census for the 197 census block group (CBG) study area. Neighborhood deprivation and vehicle availability were calculated for each CBG. Minimum distance was determined by calculating network distance from the population-weighted center of each CBG to the nearest supercenter, supermarket, grocery, convenience store, dollar store, mass merchandiser, and fast food restaurant. Coverage was determined by calculating the number of each type of food store and fast food restaurant within a network distance of 1, 3, and 5 miles of each population-weighted CBG center. Neighborhood need and access were examined using Spearman ranked correlations, spatial autocorrelation, and multivariate regression models that adjusted for population density. Overall, neighborhoods had best access to convenience stores, fast food restaurants, and dollar stores. After adjusting for population density, residents in neighborhoods with increased deprivation had to travel a significantly greater distance to the nearest supercenter or supermarket, grocery store, mass merchandiser, dollar store, and pharmacy for food items. The results were quite different for association of need with the number of stores within 1 mile. Deprivation was only associated with fast food restaurants; greater deprivation was associated with fewer fast food restaurants within 1 mile. CBG with greater lack of vehicle availability had slightly better access to more supercenters or supermarkets, grocery

  19. Association between neighborhood need and spatial access to food stores and fast food restaurants in neighborhoods of Colonias

    Directory of Open Access Journals (Sweden)

    Han Daikwon

    2009-02-01

    Full Text Available Abstract Objective To determine the extent to which neighborhood needs (socioeconomic deprivation and vehicle availability are associated with two criteria of food environment access: 1 distance to the nearest food store and fast food restaurant and 2 coverage (number of food stores and fast food restaurants within a specified network distance of neighborhood areas of colonias, using ground-truthed methods. Methods Data included locational points for 315 food stores and 204 fast food restaurants, and neighborhood characteristics from the 2000 U.S. Census for the 197 census block group (CBG study area. Neighborhood deprivation and vehicle availability were calculated for each CBG. Minimum distance was determined by calculating network distance from the population-weighted center of each CBG to the nearest supercenter, supermarket, grocery, convenience store, dollar store, mass merchandiser, and fast food restaurant. Coverage was determined by calculating the number of each type of food store and fast food restaurant within a network distance of 1, 3, and 5 miles of each population-weighted CBG center. Neighborhood need and access were examined using Spearman ranked correlations, spatial autocorrelation, and multivariate regression models that adjusted for population density. Results Overall, neighborhoods had best access to convenience stores, fast food restaurants, and dollar stores. After adjusting for population density, residents in neighborhoods with increased deprivation had to travel a significantly greater distance to the nearest supercenter or supermarket, grocery store, mass merchandiser, dollar store, and pharmacy for food items. The results were quite different for association of need with the number of stores within 1 mile. Deprivation was only associated with fast food restaurants; greater deprivation was associated with fewer fast food restaurants within 1 mile. CBG with greater lack of vehicle availability had slightly better

  20. Subjective neighborhood assessment and physical inactivity: An examination of neighborhood-level variance.

    Science.gov (United States)

    Prochaska, John D; Buschmann, Robert N; Jupiter, Daniel; Mutambudzi, Miriam; Peek, M Kristen

    2018-06-01

    Research suggests a linkage between perceptions of neighborhood quality and the likelihood of engaging in leisure-time physical activity. Often in these studies, intra-neighborhood variance is viewed as something to be controlled for statistically. However, we hypothesized that intra-neighborhood variance in perceptions of neighborhood quality may be contextually relevant. We examined the relationship between intra-neighborhood variance of subjective neighborhood quality and neighborhood-level reported physical inactivity across 48 neighborhoods within a medium-sized city, Texas City, Texas using survey data from 2706 residents collected between 2004 and 2006. Neighborhoods where the aggregated perception of neighborhood quality was poor also had a larger proportion of residents reporting being physically inactive. However, higher degrees of disagreement among residents within neighborhoods about their neighborhood quality was significantly associated with a lower proportion of residents reporting being physically inactive (p=0.001). Our results suggest that intra-neighborhood variability may be contextually relevant in studies seeking to better understand the relationship between neighborhood quality and behaviors sensitive to neighborhood environments, like physical activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A qualitative examination of home and neighborhood environments for obesity prevention in rural adults

    Directory of Open Access Journals (Sweden)

    Ballard Denise

    2008-12-01

    Full Text Available Abstract Background The home and neighborhood environments may be important in obesity prevention by virtue of food availability, food preparation, cues and opportunities for physical activity, and family support. To date, little research has examined how home and neighborhood environments in rural communities may support or hinder healthy eating and physical activity. This paper reports characteristics of rural homes and neighborhoods related to physical activity environments, availability of healthy foods, and family support for physical activity and maintaining an ideal body weight. Methods In-depth interviews were conducted with 60 African American and White adults over 50 years of age in two rural counties in Southwest Georgia. Interviews were transcribed verbatim and coded independently by two members of the research team using standard methods of qualitative analysis. Themes were then identified and data matrices were used to identify patterns by gender or race. Results Neighborhood features that supported physical activity were plenty of land, minimal traffic and living in a safe and friendly neighborhood. The major barrier was lack of recreational facilities. The majority of participants were not physically active with their family members due to schedule conflicts and lack of time. Family member-initiated efforts to encourage physical activity met with mixed results, with refusals, procrastination, and increased activity all reported. Participants generally reported it was easy to get healthy foods, although cost barriers and the need to drive to a larger town for a supermarket with good variety were noted as obstacles. Family conversations about weight had occurred for about half of the participants, with reactions ranging from agreement about the need to lose weight to frustration. Conclusion This study suggests that successful environmental change strategies to promote physical activity and healthy eating in rural neighborhoods may

  2. Large Neighborhood Search

    DEFF Research Database (Denmark)

    Pisinger, David; Røpke, Stefan

    2010-01-01

    Heuristics based on large neighborhood search have recently shown outstanding results in solving various transportation and scheduling problems. Large neighborhood search methods explore a complex neighborhood by use of heuristics. Using large neighborhoods makes it possible to find better...... candidate solutions in each iteration and hence traverse a more promising search path. Starting from the large neighborhood search method,we give an overview of very large scale neighborhood search methods and discuss recent variants and extensions like variable depth search and adaptive large neighborhood...

  3. Incorporating Neighborhood Choice in a Model of Neighborhood Effects on Income.

    Science.gov (United States)

    van Ham, Maarten; Boschman, Sanne; Vogel, Matt

    2018-05-09

    Studies of neighborhood effects often attempt to identify causal effects of neighborhood characteristics on individual outcomes, such as income, education, employment, and health. However, selection looms large in this line of research, and it has been argued that estimates of neighborhood effects are biased because people nonrandomly select into neighborhoods based on their preferences, income, and the availability of alternative housing. We propose a two-step framework to disentangle selection processes in the relationship between neighborhood deprivation and earnings. We model neighborhood selection using a conditional logit model, from which we derive correction terms. Driven by the recognition that most households prefer certain types of neighborhoods rather than specific areas, we employ a principle components analysis to reduce these terms into eight correction components. We use these to adjust parameter estimates from a model of subsequent neighborhood effects on individual income for the unequal probability that a household chooses to live in a particular type of neighborhood. We apply this technique to administrative data from the Netherlands. After we adjust for the differential sorting of households into certain types of neighborhoods, the effect of neighborhood income on individual income diminishes but remains significant. These results further emphasize that researchers need to be attuned to the role of selection bias when assessing the role of neighborhood effects on individual outcomes. Perhaps more importantly, the persistent effect of neighborhood deprivation on subsequent earnings suggests that neighborhood effects reflect more than the shared characteristics of neighborhood residents: place of residence partially determines economic well-being.

  4. Geographically weighted regression model on poverty indicator

    Science.gov (United States)

    Slamet, I.; Nugroho, N. F. T. A.; Muslich

    2017-12-01

    In this research, we applied geographically weighted regression (GWR) for analyzing the poverty in Central Java. We consider Gaussian Kernel as weighted function. The GWR uses the diagonal matrix resulted from calculating kernel Gaussian function as a weighted function in the regression model. The kernel weights is used to handle spatial effects on the data so that a model can be obtained for each location. The purpose of this paper is to model of poverty percentage data in Central Java province using GWR with Gaussian kernel weighted function and to determine the influencing factors in each regency/city in Central Java province. Based on the research, we obtained geographically weighted regression model with Gaussian kernel weighted function on poverty percentage data in Central Java province. We found that percentage of population working as farmers, population growth rate, percentage of households with regular sanitation, and BPJS beneficiaries are the variables that affect the percentage of poverty in Central Java province. In this research, we found the determination coefficient R2 are 68.64%. There are two categories of district which are influenced by different of significance factors.

  5. Rao-Blackwellization for Adaptive Gaussian Sum Nonlinear Model Propagation

    Science.gov (United States)

    Semper, Sean R.; Crassidis, John L.; George, Jemin; Mukherjee, Siddharth; Singla, Puneet

    2015-01-01

    When dealing with imperfect data and general models of dynamic systems, the best estimate is always sought in the presence of uncertainty or unknown parameters. In many cases, as the first attempt, the Extended Kalman filter (EKF) provides sufficient solutions to handling issues arising from nonlinear and non-Gaussian estimation problems. But these issues may lead unacceptable performance and even divergence. In order to accurately capture the nonlinearities of most real-world dynamic systems, advanced filtering methods have been created to reduce filter divergence while enhancing performance. Approaches, such as Gaussian sum filtering, grid based Bayesian methods and particle filters are well-known examples of advanced methods used to represent and recursively reproduce an approximation to the state probability density function (pdf). Some of these filtering methods were conceptually developed years before their widespread uses were realized. Advanced nonlinear filtering methods currently benefit from the computing advancements in computational speeds, memory, and parallel processing. Grid based methods, multiple-model approaches and Gaussian sum filtering are numerical solutions that take advantage of different state coordinates or multiple-model methods that reduced the amount of approximations used. Choosing an efficient grid is very difficult for multi-dimensional state spaces, and oftentimes expensive computations must be done at each point. For the original Gaussian sum filter, a weighted sum of Gaussian density functions approximates the pdf but suffers at the update step for the individual component weight selections. In order to improve upon the original Gaussian sum filter, Ref. [2] introduces a weight update approach at the filter propagation stage instead of the measurement update stage. This weight update is performed by minimizing the integral square difference between the true forecast pdf and its Gaussian sum approximation. By adaptively updating

  6. Active living neighborhoods: is neighborhood walkability a key element for Belgian adolescents?

    Science.gov (United States)

    De Meester, Femke; Van Dyck, Delfien; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Sallis, James F; Cardon, Greet

    2012-01-04

    In adult research, neighborhood walkability has been acknowledged as an important construct among the built environmental correlates of physical activity. Research into this association has only recently been extended to adolescents and the current empirical evidence is not consistent. This study investigated whether neighborhood walkability and neighborhood socioeconomic status (SES) are associated with physical activity among Belgian adolescents and whether the association between neighborhood walkability and physical activity is moderated by neighborhood SES and gender. In Ghent (Belgium), 32 neighborhoods were selected based on GIS-based walkability and SES derived from census data. In total, 637 adolescents (aged 13-15 year, 49.6% male) participated in the study. Physical activity was assessed using accelerometers and the Flemish Physical Activity Questionnaire. To analyze the associations between neighborhood walkability, neighborhood SES and individual physical activity, multivariate multi-level regression analyses were conducted. Only in low-SES neighborhoods, neighborhood walkability was positively associated with accelerometer-based moderate to vigorous physical activity and the average activity level expressed in counts/minute. For active transport to and from school, cycling for transport during leisure time and sport during leisure time no association with neighborhood walkability nor, with neighborhood SES was found. For walking for transport during leisure time a negative association with neighborhood SES was found. Gender did not moderate the associations of neighborhood walkability and SES with adolescent physical activity. Neighborhood walkability was related to accelerometer-based physical activity only among adolescent boys and girls living in low-SES neighborhoods. The relation of built environment to adolescent physical activity may depend on the context.

  7. Independent Effects of Neighborhood Poverty and Psychosocial Stress on Obesity Over Time.

    Science.gov (United States)

    Kwarteng, Jamila L; Schulz, Amy J; Mentz, Graciela B; Israel, Barbara A; Perkins, Denise White

    2017-12-01

    The objective of the study was to examine the independent effects of neighborhood poverty and psychosocial stress on increases in central adiposity over time. Data are from a community sample of 157 Non-Hispanic Black, Non-Hispanic White, and Hispanic adults collected in 2002-2003 and 2007-2008, and from the 2000 Decennial Census. The dependent variable was waist circumference. Independent variables included neighborhood poverty, perceived neighborhood physical environment, family stress, safety stress, everyday unfair treatment, and a cumulative stress index. Weighted 3-level hierarchical linear regression models for a continuous outcome were used to assess the effects of neighborhood poverty and psychosocial stress on central adiposity over time. We also assessed whether psychosocial stress mediated the association between neighborhood poverty and central adiposity. Neighborhood poverty and everyday unfair treatment at baseline were independently associated with increases in central adiposity over time, accounting for the other indicators of stress. Perceptions of the neighborhood physical environment and cumulative stress mediated associations between neighborhood poverty and central adiposity. Results suggest that residing in neighborhoods with higher concentrations of poverty and exposure to everyday unfair treatment independently heighten risk of increased central adiposity over time. Associations between neighborhood poverty and central adiposity were mediated by perceptions of the neighborhood physical environment and by the cumulative stress index. Public health strategies to reduce obesity should consider neighborhood poverty and exposure to multiple sources of psychosocial stress, including everyday unfair treatment.

  8. Active living neighborhoods: is neighborhood walkability a key element for Belgian adolescents?

    Directory of Open Access Journals (Sweden)

    De Meester Femke

    2012-01-01

    Full Text Available Abstract Background In adult research, neighborhood walkability has been acknowledged as an important construct among the built environmental correlates of physical activity. Research into this association has only recently been extended to adolescents and the current empirical evidence is not consistent. This study investigated whether neighborhood walkability and neighborhood socioeconomic status (SES are associated with physical activity among Belgian adolescents and whether the association between neighborhood walkability and physical activity is moderated by neighborhood SES and gender. Methods In Ghent (Belgium, 32 neighborhoods were selected based on GIS-based walkability and SES derived from census data. In total, 637 adolescents (aged 13-15 year, 49.6% male participated in the study. Physical activity was assessed using accelerometers and the Flemish Physical Activity Questionnaire. To analyze the associations between neighborhood walkability, neighborhood SES and individual physical activity, multivariate multi-level regression analyses were conducted. Results Only in low-SES neighborhoods, neighborhood walkability was positively associated with accelerometer-based moderate to vigorous physical activity and the average activity level expressed in counts/minute. For active transport to and from school, cycling for transport during leisure time and sport during leisure time no association with neighborhood walkability nor, with neighborhood SES was found. For walking for transport during leisure time a negative association with neighborhood SES was found. Gender did not moderate the associations of neighborhood walkability and SES with adolescent physical activity. Conclusions Neighborhood walkability was related to accelerometer-based physical activity only among adolescent boys and girls living in low-SES neighborhoods. The relation of built environment to adolescent physical activity may depend on the context.

  9. Label Propagation with α-Degree Neighborhood Impact for Network Community Detection

    Directory of Open Access Journals (Sweden)

    Heli Sun

    2014-01-01

    Full Text Available Community detection is an important task for mining the structure and function of complex networks. In this paper, a novel label propagation approach with α-degree neighborhood impact is proposed for efficiently and effectively detecting communities in networks. Firstly, we calculate the neighborhood impact of each node in a network within the scope of its α-degree neighborhood network by using an iterative approach. To mitigate the problems of visiting order correlation and convergence difficulty when updating the node labels asynchronously, our method updates the labels in an ascending order on the α-degree neighborhood impact of all the nodes. The α-degree neighborhood impact is also taken as the updating weight value, where the parameter impact scope α can be set to a positive integer. Experimental results from several real-world and synthetic networks show that our method can reveal the community structure in networks rapidly and accurately. The performance of our method is better than other label propagation based methods.

  10. Neighborhood choices, neighborhood effects and housing vouchers

    OpenAIRE

    Davis, Morris A.; Gregory, Jesse; Hartley, Daniel A.; Tan, Kegon T. K.

    2017-01-01

    We study how households choose neighborhoods, how neighborhoods affect child ability, and how housing vouchers influence neighborhood choices and child outcomes. We use two new panel data sets with tract-level detail for Los Angeles county to estimate a dynamic model of optimal tract-level location choice for renting households and, separately, the impact of living in a given tract on child test scores (which we call "child ability" throughout). We simulate optimal location choices and change...

  11. Positive Neighborhood Norms Buffer Ethnic Diversity Effects on Neighborhood Dissatisfaction, Perceived Neighborhood Disadvantage, and Moving Intentions.

    Science.gov (United States)

    Van Assche, Jasper; Asbrock, Frank; Roets, Arne; Kauff, Mathias

    2018-05-01

    Positive neighborhood norms, such as strong local networks, are critical to people's satisfaction with, perceived disadvantage of, and intentions to stay in their neighborhood. At the same time, local ethnic diversity is said to be detrimental for these community outcomes. Integrating both frameworks, we tested whether the negative consequences of diversity occur even when perceived social norms are positive. Study 1 ( N = 1,760 German adults) showed that perceptions of positive neighborhood norms buffered against the effects of perceived diversity on moving intentions via neighborhood satisfaction and perceived neighborhood disadvantage. Study 2 ( N = 993 Dutch adults) replicated and extended this moderated mediation model using other characteristics of diversity (i.e., objective and estimated minority proportions). Multilevel analyses again revealed consistent buffering effects of positive neighborhood norms. Our findings are discussed in light of the ongoing public and political debate concerning diversity and social and communal life.

  12. Diffusion-weighted MR imaging of pancreatic cancer: A comparison of mono-exponential, bi-exponential and non-Gaussian kurtosis models.

    Science.gov (United States)

    Kartalis, Nikolaos; Manikis, Georgios C; Loizou, Louiza; Albiin, Nils; Zöllner, Frank G; Del Chiaro, Marco; Marias, Kostas; Papanikolaou, Nikolaos

    2016-01-01

    To compare two Gaussian diffusion-weighted MRI (DWI) models including mono-exponential and bi-exponential, with the non-Gaussian kurtosis model in patients with pancreatic ductal adenocarcinoma. After written informed consent, 15 consecutive patients with pancreatic ductal adenocarcinoma underwent free-breathing DWI (1.5T, b-values: 0, 50, 150, 200, 300, 600 and 1000 s/mm 2 ). Mean values of DWI-derived metrics ADC, D, D*, f, K and D K were calculated from multiple regions of interest in all tumours and non-tumorous parenchyma and compared. Area under the curve was determined for all metrics. Mean ADC and D K showed significant differences between tumours and non-tumorous parenchyma (both P  < 0.001). Area under the curve for ADC, D, D*, f, K, and D K were 0.77, 0.52, 0.53, 0.62, 0.42, and 0.84, respectively. ADC and D K could differentiate tumours from non-tumorous parenchyma with the latter showing a higher diagnostic accuracy. Correction for kurtosis effects has the potential to increase the diagnostic accuracy of DWI in patients with pancreatic ductal adenocarcinoma.

  13. Interconversion of pure Gaussian states requiring non-Gaussian operations

    Science.gov (United States)

    Jabbour, Michael G.; García-Patrón, Raúl; Cerf, Nicolas J.

    2015-01-01

    We analyze the conditions under which local operations and classical communication enable entanglement transformations between bipartite pure Gaussian states. A set of necessary and sufficient conditions had been found [G. Giedke et al., Quant. Inf. Comput. 3, 211 (2003)] for the interconversion between such states that is restricted to Gaussian local operations and classical communication. Here, we exploit majorization theory in order to derive more general (sufficient) conditions for the interconversion between bipartite pure Gaussian states that goes beyond Gaussian local operations. While our technique is applicable to an arbitrary number of modes for each party, it allows us to exhibit surprisingly simple examples of 2 ×2 Gaussian states that necessarily require non-Gaussian local operations to be transformed into each other.

  14. Choice Neighborhood Grantees

    Data.gov (United States)

    Department of Housing and Urban Development — Choice Neighborhoods grants transform distressed neighborhoods, public and assisted projects into viable and sustainable mixed-income neighborhoods by linking...

  15. Neighborhood Design for Walking and Biking

    Science.gov (United States)

    Brown, Barbara B.; Smith, Ken R.; Hanson, Heidi; Fan, Jessie X.; Kowaleski-Jones, Lori; Zick, Cathleen D.

    2013-01-01

    Background Neighborhood designs often relate to physical activity and to BMI. Purpose Does neighborhood walkability/bikeability relate to BMI and obesity risk and does moderate-to-vigorous physical activity (MVPA) account for some of the relationship? Methods Census 2000 provided walkability/bikeability measures—block group proportions of workers who walk or bike to work, housing age, and population density—and National Health and Nutrition Examination Study (NHANES 2003–2006) provided MVPA accelerometer measures. Regression analyses (2011–2012) adjusted for geographic clustering and multiple control variables. Results Greater density and older housing were associated with lower male BMI in bivariate analyses, but there were no density and housing age effects in multivariate models. For women, greater proportions of neighborhood workers who walk to work (M=0.02) and more MVPA was associated with lower BMI and lower obesity risk. For men, greater proportions of workers who bike to work (M=0.004) and more MVPA was associated with lower BMI and obesity risk. For both effects, MVPA partially mediated the relationships between walkability/bikeability and BMI. If such associations are causal, doubling walk and bike-to-work proportions (to 0.04 and 0.008) would have –0.3 and –0.33 effects on the average BMIs of adult women and men living in the neighborhood. This equates to 1.5 lbs for a 64” woman and 2.3 lbs for a 69” man. Conclusions Although walking/biking to work is rare in the U.S., greater proportions of such workers in neighborhoods relate to lower weight and higher MVPA. Bikeability merits greater attention as a modifiable activity-friendliness factor, particularly for men. PMID:23415119

  16. Perceptions as the crucial link? The mediating role of neighborhood perceptions in the relationship between the neighborhood context and neighborhood cohesion.

    Science.gov (United States)

    Laméris, Joran; Hipp, John R; Tolsma, Jochem

    2018-05-01

    This study examines the effects of neighborhood racial in-group size, economic deprivation and the prevalence of crime on neighborhood cohesion among U.S. whites. We explore to what extent residents' perceptions of their neighborhood mediate these macro-micro relationships. We use a recent individual-level data set, the American Social Fabric Study (2012/2013), enriched with contextual-level data from the U.S. Census Bureau (2010) and employ multi-level structural equation models. We show that the racial in-group size is positively related to neighborhood cohesion and that neighborhood cohesion is lower in communities with a high crime rate. Individuals' perceptions of the racial in-group size partly mediate the relationship between the objective racial in-group size and neighborhood cohesion. Residents' perceptions of unsafety from crime also appear to be a mediating factor, not only for the objective crime rate but also for the objective racial in-group size. This is in line with our idea that racial stereotypes link racial minorities to crime whereby neighborhoods with a large non-white population are perceived to be more unsafe. Residents of the same neighborhood differ in how they perceive the degree of economic decay of the neighborhood and this causes them to evaluate neighborhood cohesion differently, however perceptions of neighborhood economic decay do not explain the link between the objective neighborhood context and neighborhood cohesion. Copyright © 2018. Published by Elsevier Inc.

  17. Neighborhood solutions for neighborhood problems: an empirically based violence prevention collaboration.

    Science.gov (United States)

    Randall, J; Swenson, C C; Henggeler, S W

    1999-12-01

    Youth antisocial behavior is influenced, in part, by neighborhood context. Yet, rather than attempting to ameliorate factors contributing to youth antisocial behavior, service dollars are primarily devoted to expensive and often ineffective out-of-home placements. This article describes the development and implementation of a collaborative partnership designed to empower an economically disadvantaged neighborhood to address violent criminal behavior, substance abuse, and other serious antisocial problems of its youth while maintaining youth in the neighborhood. Through a collaboration between a university research center and neighborhood stakeholders, services are being provided to address the key priorities identified by neighborhood residents, and extensive efforts are being made to develop family and neighborhood contexts that are conducive to prosocial youth behavior.

  18. Non-gaussian turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Hoejstrup, J [NEG Micon Project Development A/S, Randers (Denmark); Hansen, K S [Denmarks Technical Univ., Dept. of Energy Engineering, Lyngby (Denmark); Pedersen, B J [VESTAS Wind Systems A/S, Lem (Denmark); Nielsen, M [Risoe National Lab., Wind Energy and Atmospheric Physics, Roskilde (Denmark)

    1999-03-01

    The pdf`s of atmospheric turbulence have somewhat wider tails than a Gaussian, especially regarding accelerations, whereas velocities are close to Gaussian. This behaviour is being investigated using data from a large WEB-database in order to quantify the amount of non-Gaussianity. Models for non-Gaussian turbulence have been developed, by which artificial turbulence can be generated with specified distributions, spectra and cross-correlations. The artificial time series will then be used in load models and the resulting loads in the Gaussian and the non-Gaussian cases will be compared. (au)

  19. Gaussian vs non-Gaussian turbulence: impact on wind turbine loads

    DEFF Research Database (Denmark)

    Berg, Jacob; Natarajan, Anand; Mann, Jakob

    2016-01-01

    taking into account the safety factor for extreme moments. Other extreme load moments as well as the fatigue loads are not affected because of the use of non-Gaussian turbulent inflow. It is suggested that the turbine thus acts like a low-pass filter that averages out the non-Gaussian behaviour, which......From large-eddy simulations of atmospheric turbulence, a representation of Gaussian turbulence is constructed by randomizing the phases of the individual modes of variability. Time series of Gaussian turbulence are constructed and compared with its non-Gaussian counterpart. Time series from the two...

  20. Local Geographic Variation of Public Services Inequality: Does the Neighborhood Scale Matter?

    Science.gov (United States)

    Wei, Chunzhu; Cabrera-Barona, Pablo; Blaschke, Thomas

    2016-01-01

    This study aims to explore the effect of the neighborhood scale when estimating public services inequality based on the aggregation of social, environmental, and health-related indicators. Inequality analyses were carried out at three neighborhood scales: the original census blocks and two aggregated neighborhood units generated by the spatial “k”luster analysis by the tree edge removal (SKATER) algorithm and the self-organizing map (SOM) algorithm. Then, we combined a set of health-related public services indicators with the geographically weighted principal components analyses (GWPCA) and the principal components analyses (PCA) to measure the public services inequality across all multi-scale neighborhood units. Finally, a statistical test was applied to evaluate the scale effects in inequality measurements by combining all available field survey data. We chose Quito as the case study area. All of the aggregated neighborhood units performed better than the original census blocks in terms of the social indicators extracted from a field survey. The SKATER and SOM algorithms can help to define the neighborhoods in inequality analyses. Moreover, GWPCA performs better than PCA in multivariate spatial inequality estimation. Understanding the scale effects is essential to sustain a social neighborhood organization, which, in turn, positively affects social determinants of public health and public quality of life. PMID:27706072

  1. Association between neighborhood safety and overweight status among urban adolescents

    Directory of Open Access Journals (Sweden)

    Johnson Renee M

    2009-08-01

    Full Text Available Abstract Background Neighborhood safety may be an important social environmental determinant of overweight. We examined the relationship between perceived neighborhood safety and overweight status, and assessed the validity of reported neighborhood safety among a representative community sample of urban adolescents (who were racially and ethnically diverse. Methods Data come from the 2006 Boston Youth Survey, a cross-sectional study in which public high school students in Boston, MA completed a pencil-and-paper survey. The study used a two-stage, stratified sampling design whereby schools and then 9th–12th grade classrooms within schools were selected (the analytic sample included 1,140 students. Students reported their perceptions of neighborhood safety and several associated dimensions. With self-reported height and weight data, we computed body mass index (BMI, kg/m2 for the adolescents based on CDC growth charts. Chi-square statistics and corresponding p-values were computed to compare perceived neighborhood safety by the several associated dimensions. Prevalence ratios (PRs and 95% confidence intervals (CI were calculated to examine the association between perceived neighborhood safety and the prevalence of overweight status controlling for relevant covariates and school site. Results More than one-third (35.6% of students said they always felt safe in their neighborhood, 43.9% said they sometimes felt safe, 11.6% rarely felt safe, and 8.9% never felt safe. Those students who reported that they rarely or never feel safe in their neighborhoods were more likely than those who said they always or sometimes feel safe to believe that gang violence was a serious problem in their neighborhood or school (68.0% vs. 44.1%, p p = 0.025. In the fully adjusted model (including grade and school stratified by race/ethnicity, we found a statistically significant association between feeling unsafe in one's own neighborhood and overweight status among

  2. Increasing overweight and obesity erodes engagement in one's neighborhood by women, but not men.

    Science.gov (United States)

    Schuster, Roseanne C; Han, Seung Yong; Brewis, Alexandra A; Wutich, Amber

    2018-06-01

    Obesity is socially stigmatized in the U.S., especially for women. Significant research has focused on the role that the social and built environments of neighborhoods play in shaping obesity. However, the role of obesity in shaping neighborhood social structure has been largely overlooked. We test the hypothesis that large body size inhibits an individual's engagement in his or her neighborhood. Our study objectives are to assess if (1) body size (body mass index) interacts with gender to predict engagement in one's neighborhood (neighborhood engagement) and (2) if bonding social capital interacts with gender to predict neighborhood engagement independent of body size. We used data collected from the cross-sectional 2011 Phoenix Area Social Survey (PASS), which systematically sampled residents across four neighborhood types (core urban, urban fringe, suburban, retirement) across the Phoenix Metopolitian Area. Survey data was analyzed using logistic regression for 804 participants, including 35% for whom missing data was computed using multiple imputation. We found that as body size increases, women-but not men-have reduced engagement in their neighborhood, independent of bonding social capital and other key covariates (objective 1). We did not observe the interaction between gender and bonding social capital associated with neighborhood engagement (objective 2). Prior scholarship suggests obesity clusters in neighborhoods due to processes of social, economic, and environmental disadvantage. This finding suggests bi-directionality: obesity could, in turn, undermine neighborhood engagement through the mechanism of weight stigma and discrimination.

  3. Topological recursion for Gaussian means and cohomological field theories

    Science.gov (United States)

    Andersen, J. E.; Chekhov, L. O.; Norbury, P.; Penner, R. C.

    2015-12-01

    We introduce explicit relations between genus-filtrated s-loop means of the Gaussian matrix model and terms of the genus expansion of the Kontsevich-Penner matrix model (KPMM), which is the generating function for volumes of discretized (open) moduli spaces M g,s disc (discrete volumes). Using these relations, we express Gaussian means in all orders of the genus expansion as polynomials in special times weighted by ancestor invariants of an underlying cohomological field theory. We translate the topological recursion of the Gaussian model into recurrence relations for the coefficients of this expansion, which allows proving that they are integers and positive. We find the coefficients in the first subleading order for M g,1 for all g in three ways: using the refined Harer-Zagier recursion, using the Givental-type decomposition of the KPMM, and counting diagrams explicitly.

  4. Gaussian entanglement revisited

    Science.gov (United States)

    Lami, Ludovico; Serafini, Alessio; Adesso, Gerardo

    2018-02-01

    We present a novel approach to the separability problem for Gaussian quantum states of bosonic continuous variable systems. We derive a simplified necessary and sufficient separability criterion for arbitrary Gaussian states of m versus n modes, which relies on convex optimisation over marginal covariance matrices on one subsystem only. We further revisit the currently known results stating the equivalence between separability and positive partial transposition (PPT) for specific classes of Gaussian states. Using techniques based on matrix analysis, such as Schur complements and matrix means, we then provide a unified treatment and compact proofs of all these results. In particular, we recover the PPT-separability equivalence for: (i) Gaussian states of 1 versus n modes; and (ii) isotropic Gaussian states. In passing, we also retrieve (iii) the recently established equivalence between separability of a Gaussian state and and its complete Gaussian extendability. Our techniques are then applied to progress beyond the state of the art. We prove that: (iv) Gaussian states that are invariant under partial transposition are necessarily separable; (v) the PPT criterion is necessary and sufficient for separability for Gaussian states of m versus n modes that are symmetric under the exchange of any two modes belonging to one of the parties; and (vi) Gaussian states which remain PPT under passive optical operations can not be entangled by them either. This is not a foregone conclusion per se (since Gaussian bound entangled states do exist) and settles a question that had been left unanswered in the existing literature on the subject. This paper, enjoyable by both the quantum optics and the matrix analysis communities, overall delivers technical and conceptual advances which are likely to be useful for further applications in continuous variable quantum information theory, beyond the separability problem.

  5. Non-Gaussian bias: insights from discrete density peaks

    CERN Document Server

    Desjacques, Vincent; Riotto, Antonio

    2013-01-01

    Corrections induced by primordial non-Gaussianity to the linear halo bias can be computed from a peak-background split or the widespread local bias model. However, numerical simulations clearly support the prediction of the former, in which the non-Gaussian amplitude is proportional to the linear halo bias. To understand better the reasons behind the failure of standard Lagrangian local bias, in which the halo overdensity is a function of the local mass overdensity only, we explore the effect of a primordial bispectrum on the 2-point correlation of discrete density peaks. We show that the effective local bias expansion to peak clustering vastly simplifies the calculation. We generalize this approach to excursion set peaks and demonstrate that the resulting non-Gaussian amplitude, which is a weighted sum of quadratic bias factors, precisely agrees with the peak-background split expectation, which is a logarithmic derivative of the halo mass function with respect to the normalisation amplitude. We point out tha...

  6. Neighborhood context and health: How neighborhood social capital affects individual health

    NARCIS (Netherlands)

    Mohnen, S.M.

    2012-01-01

    Does it matter for my health in which neighborhood I live? The fact is, health is determined not only by individual characteristics but also by the neighborhood in which someone lives. This thesis shows that health clusters in Dutch neighborhoods and that this is not only a composition effect (that

  7. Gaussian measures of entanglement versus negativities: Ordering of two-mode Gaussian states

    International Nuclear Information System (INIS)

    Adesso, Gerardo; Illuminati, Fabrizio

    2005-01-01

    We study the entanglement of general (pure or mixed) two-mode Gaussian states of continuous-variable systems by comparing the two available classes of computable measures of entanglement: entropy-inspired Gaussian convex-roof measures and positive partial transposition-inspired measures (negativity and logarithmic negativity). We first review the formalism of Gaussian measures of entanglement, adopting the framework introduced in M. M. Wolf et al., Phys. Rev. A 69, 052320 (2004), where the Gaussian entanglement of formation was defined. We compute explicitly Gaussian measures of entanglement for two important families of nonsymmetric two-mode Gaussian state: namely, the states of extremal (maximal and minimal) negativities at fixed global and local purities, introduced in G. Adesso et al., Phys. Rev. Lett. 92, 087901 (2004). This analysis allows us to compare the different orderings induced on the set of entangled two-mode Gaussian states by the negativities and by the Gaussian measures of entanglement. We find that in a certain range of values of the global and local purities (characterizing the covariance matrix of the corresponding extremal states), states of minimum negativity can have more Gaussian entanglement of formation than states of maximum negativity. Consequently, Gaussian measures and negativities are definitely inequivalent measures of entanglement on nonsymmetric two-mode Gaussian states, even when restricted to a class of extremal states. On the other hand, the two families of entanglement measures are completely equivalent on symmetric states, for which the Gaussian entanglement of formation coincides with the true entanglement of formation. Finally, we show that the inequivalence between the two families of continuous-variable entanglement measures is somehow limited. Namely, we rigorously prove that, at fixed negativities, the Gaussian measures of entanglement are bounded from below. Moreover, we provide some strong evidence suggesting that they

  8. Hybrid algorithm of ensemble transform and importance sampling for assimilation of non-Gaussian observations

    Directory of Open Access Journals (Sweden)

    Shin'ya Nakano

    2014-05-01

    Full Text Available A hybrid algorithm that combines the ensemble transform Kalman filter (ETKF and the importance sampling approach is proposed. Since the ETKF assumes a linear Gaussian observation model, the estimate obtained by the ETKF can be biased in cases with nonlinear or non-Gaussian observations. The particle filter (PF is based on the importance sampling technique, and is applicable to problems with nonlinear or non-Gaussian observations. However, the PF usually requires an unrealistically large sample size in order to achieve a good estimation, and thus it is computationally prohibitive. In the proposed hybrid algorithm, we obtain a proposal distribution similar to the posterior distribution by using the ETKF. A large number of samples are then drawn from the proposal distribution, and these samples are weighted to approximate the posterior distribution according to the importance sampling principle. Since the importance sampling provides an estimate of the probability density function (PDF without assuming linearity or Gaussianity, we can resolve the bias due to the nonlinear or non-Gaussian observations. Finally, in the next forecast step, we reduce the sample size to achieve computational efficiency based on the Gaussian assumption, while we use a relatively large number of samples in the importance sampling in order to consider the non-Gaussian features of the posterior PDF. The use of the ETKF is also beneficial in terms of the computational simplicity of generating a number of random samples from the proposal distribution and in weighting each of the samples. The proposed algorithm is not necessarily effective in case that the ensemble is located distant from the true state. However, monitoring the effective sample size and tuning the factor for covariance inflation could resolve this problem. In this paper, the proposed hybrid algorithm is introduced and its performance is evaluated through experiments with non-Gaussian observations.

  9. Neighborhood walkability and hospital treatment costs: A first assessment.

    Science.gov (United States)

    Yu, Yan; Davey, Rachel; Cochrane, Tom; Learnihan, Vincent; Hanigan, Ivan C; Bagheri, Nasser

    2017-06-01

    Health system expenditure is a global concern, with hospital cost a major component. Built environment has been found to affect physical activity and health outcomes. The purpose of the study was a first assessment of the relationship between neighborhood walkability and hospital treatment costs. For 88 neighborhoods in the Australian Capital Territory (ACT), 2011-2013, a total of 30,690 public hospital admissions for the treatment of four diagnostic groups (cancers, endocrine, nutritional and metabolic diseases, circulatory diseases and respiratory diseases) were extracted from the ACT admitted patient care database and analyzed in relation to the Walk Score® index as a measure of walkability. Hospital cost was calculated according to the cost weight of the diagnosis related group assigned to each admission. Linear regressions were used to analyze the associations of walkability with hospital cost per person, admissions per person and cost per admission at the neighborhood level. An inverse association with neighborhood walkability was found for cost per person and admissions per person, but not cost per admission. After adjusting for age, sex and socioeconomic status, a 20-unit increase in walkability was associated with 12.1% (95% CI: 7.1-17.0%) lower cost and 12.5% (8.1-17.0%) fewer admissions. These associations did not vary by neighborhood socioeconomic status. This exploratory analysis suggests the potential for improved population health and reduced hospital cost with greater neighborhood walkability. Further research should replicate the analysis with data from other urban settings, and focus on the behavioral mechanisms underlying the inverse walkability-hospital cost association. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Longitudinal Associations between Observed and Perceived Neighborhood Food Availability and Body Mass Index in a Multiethnic Urban Sample

    Science.gov (United States)

    Zenk, Shannon N.; Mentz, Graciela; Schulz, Amy J.; Johnson-Lawrence, Vicki; Gaines, Causandra R.

    2017-01-01

    Introduction: Blacks, Hispanics, and women of lower socioeconomic status tend to have a higher risk of obesity. Numerous studies over the past decade examined the role of the neighborhood food environment in body weight. However, few were longitudinal. Purpose: This longitudinal study examined whether multiple measures of neighborhood food…

  11. Neighborhood influences on girls' obesity risk across the transition to adolescence.

    Science.gov (United States)

    Hoyt, Lindsay T; Kushi, Lawrence H; Leung, Cindy W; Nickleach, Dana C; Adler, Nancy; Laraia, Barbara A; Hiatt, Robert A; Yen, Irene H

    2014-11-01

    The neighborhoods in which children live, play, and eat provide an environmental context that may influence obesity risk and ameliorate or exacerbate health disparities. The current study examines whether neighborhood characteristics predict obesity in a prospective cohort of girls. Participants were 174 girls (aged 8-10 years at baseline), a subset from the Cohort Study of Young Girls' Nutrition, Environment, and Transitions. Trained observers completed street audits within a 0.25-mile radius around each girl's residence. Four scales (food and service retail, recreation, walkability, and physical disorder) were created from 40 observed neighborhood features. BMI was calculated from clinically measured height and weight. Obesity was defined as BMI-for-age ≥ 95%. Logistic regression models using generalized estimating equations were used to examine neighborhood influences on obesity risk over 4 years of follow-up, controlling for race/ethnicity, pubertal status, and baseline BMI. Fully adjusted models also controlled for household income, parent education, and a census tract measure of neighborhood socioeconomic status. A 1-SD increase on the food and service retail scale was associated with a 2.27 (95% confidence interval, 1.42 to 3.61; P obese. A 1-SD increase in physical disorder was associated with a 2.41 (95% confidence interval, 1.31 to 4.44; P = .005) increased odds of being obese. Other neighborhood scales were not associated with risk for obesity. Neighborhood food and retail environment and physical disorder around a girl's home predict risk for obesity across the transition from late childhood to adolescence. Copyright © 2014 by the American Academy of Pediatrics.

  12. Durham Neighborhood Compass Neighborhoods

    Data.gov (United States)

    City and County of Durham, North Carolina — The Durham Neighborhood Compass is a quantitative indicators project with qualitative values, integrating data from local government, the Census Bureau and other...

  13. Perceptions as the crucial link? The mediating role of neighborhood perceptions in the relationship between the neighborhood context and neighborhood cohesion

    NARCIS (Netherlands)

    Lamé ris, J.G.; Hipp, J.R.; Tolsma, J.

    2018-01-01

    This study examines the effects of neighborhood racial in-group size, economic deprivation and the prevalence of crime on neighborhood cohesion among U.S. whites. We explore to what extent residents' perceptions of their neighborhood mediate these macro-micro relationships. We use a recent

  14. Adaptive Laguerre-Gaussian variant of the Gaussian beam expansion method.

    Science.gov (United States)

    Cagniot, Emmanuel; Fromager, Michael; Ait-Ameur, Kamel

    2009-11-01

    A variant of the Gaussian beam expansion method consists in expanding the Bessel function J0 appearing in the Fresnel-Kirchhoff integral into a finite sum of complex Gaussian functions to derive an analytical expression for a Laguerre-Gaussian beam diffracted through a hard-edge aperture. However, the validity range of the approximation depends on the number of expansion coefficients that are obtained by optimization-computation directly. We propose another solution consisting in expanding J0 onto a set of collimated Laguerre-Gaussian functions whose waist depends on their number and then, depending on its argument, predicting the suitable number of expansion functions to calculate the integral recursively.

  15. China’s Neighborhood Environment and Options for Neighborhood Strategy

    Institute of Scientific and Technical Information of China (English)

    ZHOU FANGYIN

    2016-01-01

    Since the 18th CPC National Congress,especially since the Central Conference on Work Relating to Neighborhood Diplomacy held in October 2013,China’s neighborhood diplomacy has been energetic,proactive and promising,achieving important results in several aspects.At the same time,it is also in face of challenges

  16. Neighborhood Quality and Labor Market Outcomes: Evidence from Quasi-Random Neighborhood Assignment of Immigrants

    DEFF Research Database (Denmark)

    Damm, Anna Piil

    2012-01-01

    of men living in the neighborhood, but positively affected by the employment rate of non-Western immigrant men and co-national men living in the neighborhood. This is strong evidence that immigrants find jobs in part through their employed immigrant and co-ethnic contacts in the neighborhood of residence...... successfully addresses the methodological problem of endogenous neighborhood selection. Taking account of location sorting, living in a socially deprived neighborhood does not affect labor market outcomes of refugee men. Furthermore, their labor market outcomes are not affected by the overall employment rate...

  17. Unbiased free energy estimates in fast nonequilibrium transformations using Gaussian mixtures

    International Nuclear Information System (INIS)

    Procacci, Piero

    2015-01-01

    In this paper, we present an improved method for obtaining unbiased estimates of the free energy difference between two thermodynamic states using the work distribution measured in nonequilibrium driven experiments connecting these states. The method is based on the assumption that any observed work distribution is given by a mixture of Gaussian distributions, whose normal components are identical in either direction of the nonequilibrium process, with weights regulated by the Crooks theorem. Using the prototypical example for the driven unfolding/folding of deca-alanine, we show that the predicted behavior of the forward and reverse work distributions, assuming a combination of only two Gaussian components with Crooks derived weights, explains surprisingly well the striking asymmetry in the observed distributions at fast pulling speeds. The proposed methodology opens the way for a perfectly parallel implementation of Jarzynski-based free energy calculations in complex systems

  18. Study on renormalization transformation for U(1) gauge theory in the neighbourhood of gaussian fixed point

    International Nuclear Information System (INIS)

    Neves, A.G.M.

    1988-01-01

    The renormalization transformation e sup(-S 1) sup((B)) const. ζ e sup(-S o (A) - V(A)) δ (B-C sub(1) A) δ sub(Ax) (A)DA for the U(1) lattice gauge theory, where S sub(o) (A) is the gaussian fixed point of the transformation, V(A) is a gauge invariant perturbation, C sub(1) is the averaging operator and δ sub(Ax) (A) fixes the local axial gauge is studied via an equivalent renormalization transformation on the 2-forms F = dA. The transformation is linearized in the neighborhood of the fixed point and then diagonalized. (author)

  19. Resource theory of non-Gaussian operations

    Science.gov (United States)

    Zhuang, Quntao; Shor, Peter W.; Shapiro, Jeffrey H.

    2018-05-01

    Non-Gaussian states and operations are crucial for various continuous-variable quantum information processing tasks. To quantitatively understand non-Gaussianity beyond states, we establish a resource theory for non-Gaussian operations. In our framework, we consider Gaussian operations as free operations, and non-Gaussian operations as resources. We define entanglement-assisted non-Gaussianity generating power and show that it is a monotone that is nonincreasing under the set of free superoperations, i.e., concatenation and tensoring with Gaussian channels. For conditional unitary maps, this monotone can be analytically calculated. As examples, we show that the non-Gaussianity of ideal photon-number subtraction and photon-number addition equal the non-Gaussianity of the single-photon Fock state. Based on our non-Gaussianity monotone, we divide non-Gaussian operations into two classes: (i) the finite non-Gaussianity class, e.g., photon-number subtraction, photon-number addition, and all Gaussian-dilatable non-Gaussian channels; and (ii) the diverging non-Gaussianity class, e.g., the binary phase-shift channel and the Kerr nonlinearity. This classification also implies that not all non-Gaussian channels are exactly Gaussian dilatable. Our resource theory enables a quantitative characterization and a first classification of non-Gaussian operations, paving the way towards the full understanding of non-Gaussianity.

  20. Neighborhood socioeconomic deprivation, perceived neighborhood factors, and cortisol responses to induced stress among healthy adults.

    Science.gov (United States)

    Barrington, Wendy E; Stafford, Mai; Hamer, Mark; Beresford, Shirley A A; Koepsell, Thomas; Steptoe, Andrew

    2014-05-01

    Associations between measures of neighborhood socioeconomic deprivation and health have been identified, yet work is needed to uncover explanatory mechanisms. One hypothesized pathway is through stress, yet the few studies that have evaluated associations between characteristics of deprived neighborhoods and biomarkers of stress are mixed. This study evaluated whether objectively measured neighborhood socioeconomic deprivation and individual perceived neighborhood characteristics (i.e. social control and fear of crime) impacted cortisol responses to an induced stressor among older healthy adults. Data from Heart Scan, a sub-study of the Whitehall II cohort, were used to generate multilevel piecewise growth-curve models of cortisol trajectories after a laboratory stressor accounting for neighborhood and demographic characteristics. Neighborhood socioeconomic deprivation was significantly associated with individual perceptions of social control and fear of crime in the neighborhood while an association with blunted cortisol reactivity was only evidence among women. Social control was significantly associated with greater cortisol reactivity and mediation between neighborhood socioeconomic deprivation and cortisol reactivity was suggested among women. These findings support a gender-dependent role of neighborhood in stress process models of health. Published by Elsevier Ltd.

  1. Neighborhood Environments and Objectively Measured Physical Activity in 11 Countries

    Science.gov (United States)

    Cerin, Ester; Cain, Kelli L; Conway, Terry L; Dyck, Delfien Van; Hinckson, Erica; Schipperijn, Jasper; Bourdeaudhuij, Ilse De; Owen, Neville; Davey, Rachel C; Hino, Adriano Akira Ferreira; Mitáš, Josef; Orzanco-Garralda, Rosario; Salvo, Deborah; Sarmiento, Olga L; Christiansen, Lars B; Macfarlane, Duncan J; Schofield, Grant; Sallis, James F

    2014-01-01

    Purpose Environmental changes are potentially effective population-level physical activity (PA) promotion strategies. However, robust multi-site evidence to guide international action for developing activity-supportive environments is lacking. We estimated pooled associations of perceived environmental attributes with objectively-measured PA outcomes; between-site differences in such associations; and, the extent to which perceived environmental attributes explain between-site differences in PA. Methods This was a cross-sectional study conducted in 16 cities located in Belgium, Brazil, Colombia, Czech Republic, Denmark, China, Mexico, New Zealand, Spain, United Kingdom, and USA. Participants were 6,968 adults residing in administrative units stratified by socio-economic status and transport-related walkability. Predictors were 10 perceived neighborhood environmental attributes. Outcome measures were accelerometry-assessed weekly minutes of moderate-to-vigorous PA (MVPA) and meeting the PA guidelines for cancer/weight gain prevention (420 min/week of MVPA). Results Most perceived neighborhood attributes were positively associated with the PA outcomes in the pooled, site-adjusted, single-predictor models. Associations were generalizable across geographical locations. Aesthetics and land use mix – access were significant predictors of both PA outcomes in the fully-adjusted models. Environmental attributes accounted for within-site variability in MVPA corresponding to a 3 min/d or 21 min/week standard deviation. Large between-site differences in PA outcomes were observed: 15.9% to 16.8% of these differences were explained by perceived environmental attributes. All neighborhood attributes were associated with between-site differences in the total effects of the perceived environment on PA outcomes. Conclusions Residents’ perceptions of neighborhood attributes that facilitate walking were positively associated with objectively-measured MVPA and meeting the guidelines

  2. Weighted fit of parametric functions to distributions: The new interface of HOBOOK with MINUIT

    International Nuclear Information System (INIS)

    Lessner, E.S.

    1989-08-01

    The fitting routines of the HBOOK package allow weighted fit of parametric functions to the contents of a one, two or N-dimensional distribution, and analysis of the function in the neighborhood of its minimum, through an interface with the MINUIT package. These routines have been rewritten so as to interface the new version of MINUIT and to allow for smooth transitions to future versions of both packages. We discuss the interface and its capabilities: it is more stable than the previous version and presents a more accurate error analysis. The fitting algorithm is based on the Fletcher method, known for its reliability. Exponential, Gaussian and polynomial fitting are provided, as well as arbitrary user-defined fitting, to one, two and N-dimensional distributions. For the latter, the user is required to provide a smooth parametric function and is given the ability to guide the algorithm in finding the desired minimum. Examples are given. 6 refs., 1 fig

  3. Radial dependence of surface streamer-channel luminosity: experimental evidence of Gaussian radiative profiles in Ar and N2

    International Nuclear Information System (INIS)

    Šimek, M; Ambrico, P F

    2012-01-01

    Radial distributions of electronically excited species produced during surface streamer propagation were obtained by applying the Abel inverse transform to projected luminosities of single streamers. The streamers were generated in an argon and nitrogen surface coplanar dielectric barrier discharge at atmospheric pressure and their magnified microscopic images were registered with high time resolution. Selected regions of the projected luminosities were processed by the Abel inverse transform procedure based on the Hankel–Fourier method assuming cylindrical symmetry of the streamer channel. Projected as well as Abel-inverted profiles were fitted by Gaussian functions. It is shown that the projected profiles, in addition to the Abel-inverted ones, can be well approximated by the sum of two coaxial Gaussians with two different half-widths and weights. The sharper Gaussian component with higher weight characterizes the radial dependence of the primary cathode-directed streamer-channel luminosity. The second (broader) Gaussian component probably originates either from the pre-breakdown Townsend phase or from the second wave propagating towards the anode. (paper)

  4. Connecting Schools to Neighborhood Revitalization: The Case of the Maple Heights Neighborhood Association

    Science.gov (United States)

    Pesch, Lawrence P.

    2014-01-01

    This case study focuses on the way a neighborhood association connects schools to broad change in an urban neighborhood of a large Midwestern city. The first section provides a review of the literature on community involvement in school and neighborhood reform. It reviews the historical origins of the current school-community relationship, the…

  5. A non-Gaussian multivariate distribution with all lower-dimensional Gaussians and related families

    KAUST Repository

    Dutta, Subhajit

    2014-07-28

    Several fascinating examples of non-Gaussian bivariate distributions which have marginal distribution functions to be Gaussian have been proposed in the literature. These examples often clarify several properties associated with the normal distribution. In this paper, we generalize this result in the sense that we construct a pp-dimensional distribution for which any proper subset of its components has the Gaussian distribution. However, the jointpp-dimensional distribution is inconsistent with the distribution of these subsets because it is not Gaussian. We study the probabilistic properties of this non-Gaussian multivariate distribution in detail. Interestingly, several popular tests of multivariate normality fail to identify this pp-dimensional distribution as non-Gaussian. We further extend our construction to a class of elliptically contoured distributions as well as skewed distributions arising from selections, for instance the multivariate skew-normal distribution.

  6. A non-Gaussian multivariate distribution with all lower-dimensional Gaussians and related families

    KAUST Repository

    Dutta, Subhajit; Genton, Marc G.

    2014-01-01

    Several fascinating examples of non-Gaussian bivariate distributions which have marginal distribution functions to be Gaussian have been proposed in the literature. These examples often clarify several properties associated with the normal distribution. In this paper, we generalize this result in the sense that we construct a pp-dimensional distribution for which any proper subset of its components has the Gaussian distribution. However, the jointpp-dimensional distribution is inconsistent with the distribution of these subsets because it is not Gaussian. We study the probabilistic properties of this non-Gaussian multivariate distribution in detail. Interestingly, several popular tests of multivariate normality fail to identify this pp-dimensional distribution as non-Gaussian. We further extend our construction to a class of elliptically contoured distributions as well as skewed distributions arising from selections, for instance the multivariate skew-normal distribution.

  7. Measuring physical neighborhood quality related to health.

    Science.gov (United States)

    Rollings, Kimberly A; Wells, Nancy M; Evans, Gary W

    2015-04-29

    Although sociodemographic factors are one aspect of understanding the effects of neighborhood environments on health, equating neighborhood quality with socioeconomic status ignores the important role of physical neighborhood attributes. Prior work on neighborhood environments and health has relied primarily on level of socioeconomic disadvantage as the indicator of neighborhood quality without attention to physical neighborhood quality. A small but increasing number of studies have assessed neighborhood physical characteristics. Findings generally indicate that there is an association between living in deprived neighborhoods and poor health outcomes, but rigorous evidence linking specific physical neighborhood attributes to particular health outcomes is lacking. This paper discusses the methodological challenges and limitations of measuring physical neighborhood environments relevant to health and concludes with proposed directions for future work.

  8. An approximate fractional Gaussian noise model with computational cost

    KAUST Repository

    Sørbye, Sigrunn H.

    2017-09-18

    Fractional Gaussian noise (fGn) is a stationary time series model with long memory properties applied in various fields like econometrics, hydrology and climatology. The computational cost in fitting an fGn model of length $n$ using a likelihood-based approach is ${\\\\mathcal O}(n^{2})$, exploiting the Toeplitz structure of the covariance matrix. In most realistic cases, we do not observe the fGn process directly but only through indirect Gaussian observations, so the Toeplitz structure is easily lost and the computational cost increases to ${\\\\mathcal O}(n^{3})$. This paper presents an approximate fGn model of ${\\\\mathcal O}(n)$ computational cost, both with direct or indirect Gaussian observations, with or without conditioning. This is achieved by approximating fGn with a weighted sum of independent first-order autoregressive processes, fitting the parameters of the approximation to match the autocorrelation function of the fGn model. The resulting approximation is stationary despite being Markov and gives a remarkably accurate fit using only four components. The performance of the approximate fGn model is demonstrated in simulations and two real data examples.

  9. Quantum information with Gaussian states

    International Nuclear Information System (INIS)

    Wang Xiangbin; Hiroshima, Tohya; Tomita, Akihisa; Hayashi, Masahito

    2007-01-01

    Quantum optical Gaussian states are a type of important robust quantum states which are manipulatable by the existing technologies. So far, most of the important quantum information experiments are done with such states, including bright Gaussian light and weak Gaussian light. Extending the existing results of quantum information with discrete quantum states to the case of continuous variable quantum states is an interesting theoretical job. The quantum Gaussian states play a central role in such a case. We review the properties and applications of Gaussian states in quantum information with emphasis on the fundamental concepts, the calculation techniques and the effects of imperfections of the real-life experimental setups. Topics here include the elementary properties of Gaussian states and relevant quantum information device, entanglement-based quantum tasks such as quantum teleportation, quantum cryptography with weak and strong Gaussian states and the quantum channel capacity, mathematical theory of quantum entanglement and state estimation for Gaussian states

  10. Maximum Correntropy Criterion Kalman Filter for α-Jerk Tracking Model with Non-Gaussian Noise

    Directory of Open Access Journals (Sweden)

    Bowen Hou

    2017-11-01

    Full Text Available As one of the most critical issues for target track, α -jerk model is an effective maneuver target track model. Non-Gaussian noises always exist in the track process, which usually lead to inconsistency and divergence of the track filter. A novel Kalman filter is derived and applied on α -jerk tracking model to handle non-Gaussian noise. The weighted least square solution is presented and the standard Kalman filter is deduced firstly. A novel Kalman filter with the weighted least square based on the maximum correntropy criterion is deduced. The robustness of the maximum correntropy criterion is also analyzed with the influence function and compared with the Huber-based filter, and, moreover, the kernel size of Gaussian kernel plays an important role in the filter algorithm. A new adaptive kernel method is proposed in this paper to adjust the parameter in real time. Finally, simulation results indicate the validity and the efficiency of the proposed filter. The comparison study shows that the proposed filter can significantly reduce the noise influence for α -jerk model.

  11. When non-Gaussian states are Gaussian: Generalization of nonseparability criterion for continuous variables

    International Nuclear Information System (INIS)

    McHugh, Derek; Buzek, Vladimir; Ziman, Mario

    2006-01-01

    We present a class of non-Gaussian two-mode continuous-variable states for which the separability criterion for Gaussian states can be employed to detect whether they are separable or not. These states reduce to the two-mode Gaussian states as a special case

  12. Neighborhood spaces

    OpenAIRE

    D. C. Kent; Won Keun Min

    2002-01-01

    Neighborhood spaces, pretopological spaces, and closure spaces are topological space generalizations which can be characterized by means of their associated interior (or closure) operators. The category NBD of neighborhood spaces and continuous maps contains PRTOP as a bicoreflective subcategory and CLS as a bireflective subcategory, whereas TOP is bireflectively embedded in PRTOP and bicoreflectively embedded in CLS. Initial and final structures are described in these categories, and it is s...

  13. Examination of perceived neighborhood characteristics and transportation on changes in physical activity and sedentary behavior: The Trial of Activity in Adolescent Girls.

    Science.gov (United States)

    Evenson, Kelly R; Murray, David M; Birnbaum, Amanda S; Cohen, Deborah A

    2010-09-01

    We examined the association between perceived neighborhood characteristics and transport and 2-year changes in accelerometer-determined nonschool MET-weighted moderate-to-vigorous physical activity (MW-MVPA) and sedentary behavior of adolescent girls. Reporting that children do not play outdoors in their neighborhood, that their neighborhood was well lit, and that there were trails in their neighborhood were each associated with significant decreases in nonschool MW-MVPA. None of the neighborhood or transportation measures was associated with changes in nonschool sedentary behavior. Further work is needed to understand the determinants of the decline in physical activity and the increase in sedentary behavior among adolescent girls. Copyright 2010 Elsevier Ltd. All rights reserved.

  14. Community, Democracy, and Neighborhood News.

    Science.gov (United States)

    Hindman, Elizabeth Blanks

    1998-01-01

    Contributes to scholarship on democracy, community, and journalism by examining the interplay between communication, democracy, and community at an inner-city neighborhood newspaper. Concludes that, through its focus on neighborhood culture, acknowledgment of conflict, and attempts to provide a forum for the neighborhood's self-definition, the…

  15. Adaptive estimation of multivariate functions using conditionally Gaussian tensor-product spline priors

    NARCIS (Netherlands)

    Jonge, de R.; Zanten, van J.H.

    2012-01-01

    We investigate posterior contraction rates for priors on multivariate functions that are constructed using tensor-product B-spline expansions. We prove that using a hierarchical prior with an appropriate prior distribution on the partition size and Gaussian prior weights on the B-spline

  16. Physical activity as a mediator of the associations between neighborhood walkability and adiposity in Belgian adults.

    Science.gov (United States)

    Van Dyck, Delfien; Cerin, Ester; Cardon, Greet; Deforche, Benedicte; Sallis, James F; Owen, Neville; de Bourdeaudhuij, Ilse

    2010-09-01

    This study examined whether physical activity (PA) and sedentary behavior mediated the relationship of neighborhood walkability with two measures of adiposity: body mass index (BMI) and waist-to-height ratio (WHTR). Twenty-four neighborhoods in Ghent, Belgium were selected, stratified by objectively assessed walkability and by socio-economic status. Participants (1200 adults aged 20-65 years) completed the International Physical Activity Questionnaire and wore an accelerometer for 7 days. Weight and height were self-reported and waist circumference was objectively measured. Accelerometer-assessed moderate-to-vigorous PA and self-reported cycling for transport mediated the associations of walkability with BMI and WHTR. Moreover, walking for transport and recreational walking significantly mediated the relationship between walkability and BMI. Sedentary behavior did not mediate associations of walkability with BMI or WHTR. These findings suggest that PA, but not sedentary behavior, is a mechanism by which walkability may affect adults' adiposity. Planning for neighborhoods to be high in walkability could have favorable effects on physical activity and weight status. Copyright 2010 Elsevier Ltd. All rights reserved.

  17. Nonlinear Bayesian Estimation of BOLD Signal under Non-Gaussian Noise

    Directory of Open Access Journals (Sweden)

    Ali Fahim Khan

    2015-01-01

    Full Text Available Modeling the blood oxygenation level dependent (BOLD signal has been a subject of study for over a decade in the neuroimaging community. Inspired from fluid dynamics, the hemodynamic model provides a plausible yet convincing interpretation of the BOLD signal by amalgamating effects of dynamic physiological changes in blood oxygenation, cerebral blood flow and volume. The nonautonomous, nonlinear set of differential equations of the hemodynamic model constitutes the process model while the weighted nonlinear sum of the physiological variables forms the measurement model. Plagued by various noise sources, the time series fMRI measurement data is mostly assumed to be affected by additive Gaussian noise. Though more feasible, the assumption may cause the designed filter to perform poorly if made to work under non-Gaussian environment. In this paper, we present a data assimilation scheme that assumes additive non-Gaussian noise, namely, the e-mixture noise, affecting the measurements. The proposed filter MAGSF and the celebrated EKF are put to test by performing joint optimal Bayesian filtering to estimate both the states and parameters governing the hemodynamic model under non-Gaussian environment. Analyses using both the synthetic and real data reveal superior performance of the MAGSF as compared to EKF.

  18. Perceived School and Neighborhood Safety, Neighborhood Violence and Academic Achievement in Urban School Children

    Science.gov (United States)

    AJ, Milam; CDM, Furr-Holden; PJ, Leaf

    2010-01-01

    Community and school violence continue to be a major public health problem, especially among urban children and adolescents. Little research has focused on the effect of school safety and neighborhood violence on academic performance. This study examines the effect of the school and neighborhood climate on academic achievement among a population of 3rd-5th grade students in an urban public school system. Community and school safety were assessed using the School Climate Survey, an annual city-wide assessment of student’s perception of school and community safety. Community violence was measured using the Neighborhood Inventory for Environmental Typology, an objective observational assessment of neighborhood characteristics. Academic achievement was measured using the Maryland State Assessment (MSA), a standardized exam given to all Maryland 3rd-8th graders. School Climate Data and MSA data were aggregated by school and grade. Objective assessments of neighborhood environment and students’ self-reported school and neighborhood safety were both strongly associated with academic performance. Increasing neighborhood violence was associated with statistically significant decreases from 4.2%-8.7% in math and reading achievement; increasing perceived safety was associated with significant increases in achievement from 16%-22%. These preliminary findings highlight the adverse impact of perceived safety and community violence exposure on primary school children’s academic performance. PMID:21197388

  19. Neighborhood Quality and Labor Market Outcomes

    DEFF Research Database (Denmark)

    Damm, Anna Piil

    of men living in the neighborhood, but positively affected by the employment rate of non-Western immigrant men and co-national men living in the neighborhood. This is strong evidence that immigrants find jobs in part through their employed immigrant and co-ethnic contacts in the neighborhood of residence...... successfully addresses the methodological problem of endogenous neighborhood selection. Taking account of location sorting, living in a socially deprived neighborhood does not affect labor market outcomes of refugee men. Furthermore, their labor market outcomes are not affected by the overall employment rate...

  20. Demonstration of non-Gaussian restricted diffusion in tumor cells using diffusion-time dependent diffusion weighted MR contrast

    Directory of Open Access Journals (Sweden)

    Tuva Roaldsdatter Hope

    2016-08-01

    Full Text Available The diffusion weighted imaging (DWI technique enables quantification of water mobility for probing microstructural properties of biological tissue, and has become an effective tool for collecting information about the underlying pathology of cancerous tissue. Measurements using multiple b-values have indicated a bi-exponential signal attenuation, ascribed to fast (high ADC and slow (low ADC diffusion components. In this empirical study, we investigate the properties of the diffusion time (∆ - dependent components of the diffusion-weighted (DW signal in a constant b-value experiment. A Xenograft GBM mouse was imaged using ∆ = 11 ms, 20 ms, 40 ms, 60 ms and b=500-4000 s/mm2 in intervals of 500s/mm2. Data was corrected for EPI distortions and the ∆-dependence on the DW signal was measured within three regions of interest (intermediate- and high-density tumor regions and normal appearing brain tissue regions (NAB. In this empirical study we verify the assumption that the slow decaying component of the DW-signal is non-Gaussian and dependent on ∆, consistent with restricted diffusion of the intracellular space. As the DW-signal as a function of ∆ is specific to restricted diffusion, manipulating ∆ at constant b-value (cb provides a complementary and direct approach for separating the restricted from the hindered diffusion component. Our results show that only tumor tissue signal of our data demonstrate ∆-dependence, based on a bi-exponential model with a restricted diffusion component, we successfully estimated the restricted ADC, signal volume fraction and cell size within each tumor ROI.

  1. Neighborhood cohesion, neighborhood disorder, and cardiometabolic risk.

    Science.gov (United States)

    Robinette, Jennifer W; Charles, Susan T; Gruenewald, Tara L

    2018-02-01

    Perceptions of neighborhood disorder (trash, vandalism) and cohesion (neighbors trust one another) are related to residents' health. Affective and behavioral factors have been identified, but often in studies using geographically select samples. We use a nationally representative sample (n = 9032) of United States older adults from the Health and Retirement Study to examine cardiometabolic risk in relation to perceptions of neighborhood cohesion and disorder. Lower cohesion is significantly related to greater cardiometabolic risk in 2006/2008 and predicts greater risk four years later (2010/2012). The longitudinal relation is partially accounted for by anxiety and physical activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. On the relationship between Gaussian stochastic blockmodels and label propagation algorithms

    International Nuclear Information System (INIS)

    Zhang, Junhao; Hu, Junfeng; Chen, Tongfei

    2015-01-01

    The problem of community detection has received great attention in recent years. Many methods have been proposed to discover communities in networks. In this paper, we propose a Gaussian stochastic blockmodel that uses Gaussian distributions to fit weight of edges in networks for non-overlapping community detection. The maximum likelihood estimation of this model has the same objective function as general label propagation with node preference. The node preference of a specific vertex turns out to be a value proportional to the intra-community eigenvector centrality (the corresponding entry in principal eigenvector of the adjacency matrix of the subgraph inside that vertex's community) under maximum likelihood estimation. Additionally, the maximum likelihood estimation of a constrained version of our model is highly related to another extension of the label propagation algorithm, namely, the label propagation algorithm under constraint. Experiments show that the proposed Gaussian stochastic blockmodel performs well on various benchmark networks. (paper)

  3. Who Gentrifies Low-Income Neighborhoods?

    Science.gov (United States)

    McKinnish, Terra; Walsh, Randall; White, T Kirk

    2010-03-01

    This paper uses confidential Census data, specifically the 1990 and 2000 Census Long Form data, to study demographic processes in neighborhoods that gentrified during the 1990's. In contrast to previous studies, the analysis is conducted at the more refined census-tract level, with a narrower definition of gentrification and more closely matched comparison neighborhoods. Furthermore, our access to individual-level data with census tract identifiers allows us to separately identify recent in-migrants and long-term residents. Our results indicate that, on average, the demographic flows associated with the gentrification of urban neighborhoods during the 1990's are not consistent with displacement and harm to minority households. In fact, taken as a whole, our results suggest that gentrification of predominantly black neighborhoods creates neighborhoods that are attractive to middle-class black households.

  4. Neighborhood-Specific and General Social Support: Which Buffers the Effect of Neighborhood Disorder on Depression?

    Science.gov (United States)

    Kim, Joongbaeck; Ross, Catherine E.

    2009-01-01

    Is neighborhood-specific social support the most effective type of social support for buffering the effect of neighborhood disorder on depression? Matching theory suggests that it is. The authors extend the research on neighborhood disorder and adult depression by showing that individuals who have higher levels of both general and…

  5. A Longitudinal Analysis of the Influence of the Neighborhood Environment on Recreational Walking within the Neighborhood: Results from RESIDE.

    Science.gov (United States)

    Christian, Hayley; Knuiman, Matthew; Divitini, Mark; Foster, Sarah; Hooper, Paula; Boruff, Bryan; Bull, Fiona; Giles-Corti, Billie

    2017-07-12

    There is limited longitudinal evidence confirming the role of neighborhood environment attributes in encouraging people to walk more or if active people simply choose to live in activity-friendly neighborhoods. Natural experiments of policy changes to create more walkable communities provide stronger evidence for a causal effect of neighborhood environments on residents' walking. We aimed to investigate longitudinal associations between objective and perceived neighborhood environment measures and neighborhood recreational walking. We analyzed longitudinal data collected over 8 yr (four surveys) from the RESIDential Environments (RESIDE) Study (Perth, Australia, 2003-2012). At each time point, participants reported the frequency and total minutes of recreational walking/week within their neighborhood and neighborhood environment perceptions. Objective measures of the neighborhood environment were generated using a Geographic Information System (GIS). Local recreational walking was influenced by objectively measured access to a medium-/large-size park, beach access, and higher street connectivity, which was reduced when adjusted for neighborhood perceptions. In adjusted models, positive perceptions of access to a park and beach, higher street connectivity, neighborhood esthetics, and safety from crime were independent determinants of increased neighborhood recreational walking. Local recreational walking increased by 9 min/wk (12% increase in frequency) for each additional perceived neighborhood attribute present. Our findings provide urban planners and policy makers with stronger causal evidence of the positive impact of well-connected neighborhoods and access to local parks of varying sizes on local residents' recreational walking and health. https://doi.org/10.1289/EHP823.

  6. Urbanism, Neighborhood Context, and Social Networks.

    Science.gov (United States)

    Cornwell, Erin York; Behler, Rachel L

    2015-09-01

    Theories of urbanism suggest that the urban context erodes individuals' strong social ties with friends and family. Recent research has narrowed focus to the neighborhood context, emphasizing how localized structural disadvantage affects community-level cohesion and social capital. In this paper, we argue that neighborhood context also shapes social ties with friends and family- particularly for community-dwelling seniors. We hypothesize that neighborhood disadvantage, residential instability, and disorder restrict residents' abilities to cultivate close relationships with neighbors and non-neighbor friends and family. Using data from the National Social Life, Health, and Aging Project (NSHAP), we find that older adults who live in disadvantaged neighborhoods have smaller social networks. Neighborhood disadvantage is also associated with less close network ties and less frequent interaction - but only among men. Furthermore, residents of disordered neighborhoods have smaller networks and weaker ties. We urge scholars to pay greater attention to how neighborhood context contributes to disparities in network-based access to resources.

  7. The neighborhoods they live in: the effects of neighborhood residence on child and adolescent outcomes.

    Science.gov (United States)

    Leventhal, T; Brooks-Gunn, J

    2000-03-01

    This article provides a comprehensive review of research on the effects of neighborhood residence on child and adolescent well-being. The first section reviews key methodological issues. The following section considers links between neighborhood characteristics and child outcomes and suggests the importance of high socioeconomic status (SES) for achievement and low SES and residential instability for behavioral/emotional outcomes. The third section identifies 3 pathways (institutional resources, relationships, and norms/collective efficacy) through which neighborhoods might influence development, and which represent an extension of models identified by C. Jencks and S. Mayer (1990) and R. J. Sampson (1992). The models provide a theoretical base for studying neighborhood mechanisms and specify different levels (individual, family, school, peer, community) at which processes may operate. Implications for an emerging developmental framework for research on neighborhoods are discussed.

  8. Iterative Mixture Component Pruning Algorithm for Gaussian Mixture PHD Filter

    Directory of Open Access Journals (Sweden)

    Xiaoxi Yan

    2014-01-01

    Full Text Available As far as the increasing number of mixture components in the Gaussian mixture PHD filter is concerned, an iterative mixture component pruning algorithm is proposed. The pruning algorithm is based on maximizing the posterior probability density of the mixture weights. The entropy distribution of the mixture weights is adopted as the prior distribution of mixture component parameters. The iterative update formulations of the mixture weights are derived by Lagrange multiplier and Lambert W function. Mixture components, whose weights become negative during iterative procedure, are pruned by setting corresponding mixture weights to zeros. In addition, multiple mixture components with similar parameters describing the same PHD peak can be merged into one mixture component in the algorithm. Simulation results show that the proposed iterative mixture component pruning algorithm is superior to the typical pruning algorithm based on thresholds.

  9. Who Gentrifies Low-Income Neighborhoods?*

    Science.gov (United States)

    McKinnish, Terra; Walsh, Randall; White, T. Kirk

    2009-01-01

    This paper uses confidential Census data, specifically the 1990 and 2000 Census Long Form data, to study demographic processes in neighborhoods that gentrified during the 1990’s. In contrast to previous studies, the analysis is conducted at the more refined census-tract level, with a narrower definition of gentrification and more closely matched comparison neighborhoods. Furthermore, our access to individual-level data with census tract identifiers allows us to separately identify recent in-migrants and long-term residents. Our results indicate that, on average, the demographic flows associated with the gentrification of urban neighborhoods during the 1990’s are not consistent with displacement and harm to minority households. In fact, taken as a whole, our results suggest that gentrification of predominantly black neighborhoods creates neighborhoods that are attractive to middle-class black households. PMID:20161532

  10. The neighborhood energy balance equation: does neighborhood food retail environment + physical activity environment = obesity? The CARDIA study.

    Directory of Open Access Journals (Sweden)

    Janne Boone-Heinonen

    Full Text Available Recent obesity prevention initiatives focus on healthy neighborhood design, but most research examines neighborhood food retail and physical activity (PA environments in isolation. We estimated joint, interactive, and cumulative impacts of neighborhood food retail and PA environment characteristics on body mass index (BMI throughout early adulthood.We used cohort data from the Coronary Artery Risk Development in Young Adults (CARDIA Study [n=4,092; Year 7 (24-42 years, 1992-1993 followed over 5 exams through Year 25 (2010-2011; 12,921 person-exam observations], with linked time-varying geographic information system-derived neighborhood environment measures. Using regression with fixed effects for individuals, we modeled time-lagged BMI as a function of food and PA resource density (counts per population and neighborhood development intensity (a composite density score. We controlled for neighborhood poverty, individual-level sociodemographics, and BMI in the prior exam; and included significant interactions between neighborhood measures and by sex. Using model coefficients, we simulated BMI reductions in response to single and combined neighborhood improvements. Simulated increase in supermarket density (from 25(th to 75(th percentile predicted inter-exam reduction in BMI of 0.09 kg/m(2 [estimate (95% CI: -0.09 (-0.16, -0.02]. Increasing commercial PA facility density predicted BMI reductions up to 0.22 kg/m(2 in men, with variation across other neighborhood features [estimate (95% CI range: -0.14 (-0.29, 0.01 to -0.22 (-0.37, -0.08]. Simultaneous increases in supermarket and commercial PA facility density predicted inter-exam BMI reductions up to 0.31 kg/m(2 in men [estimate (95% CI range: -0.23 (-0.39, -0.06 to -0.31 (-0.47, -0.15] but not women. Reduced fast food restaurant and convenience store density and increased public PA facility density and neighborhood development intensity did not predict reductions in BMI.Findings suggest that

  11. A note on the almost sure central limit theorems for the maxima of strongly dependent nonstationary Gaussian vector sequences

    Directory of Open Access Journals (Sweden)

    Xiang Zeng

    2016-06-01

    Full Text Available Abstract We prove some almost sure central limit theorems for the maxima of strongly dependent nonstationary Gaussian vector sequences under some mild conditions. The results extend the ASCLT to nonstationary Gaussian vector sequences and give substantial improvements for the weight sequence obtained by Lin et al. (Comput. Math. Appl. 62(2:635-640, 2011.

  12. Rural Neighborhood Walkability: Implications for Assessment.

    Science.gov (United States)

    Kegler, Michelle C; Alcantara, Iris; Haardörfer, Regine; Gemma, Alexandra; Ballard, Denise; Gazmararian, Julie

    2015-06-16

    Physical activity levels, including walking, are lower in the southern U.S., particularly in rural areas. This study investigated the concept of rural neighborhood walkability to aid in developing tools for assessing walkability and to identify intervention targets in rural communities. Semi-structured interviews were conducted with physically active adults (n = 29) in rural Georgia. Mean age of participants was 55.9 years; 66% were male, 76% were white, and 24% were African American. Participants drew maps of their neighborhoods and discussed the relevance of typical domains of walkability to their decisions to exercise. Comparative analyses were conducted to identify major themes. The majority felt the concept of neighborhood was applicable and viewed their neighborhood as small geographically (less than 0.5 square miles). Sidewalks were not viewed as essential for neighborhood-based physical activity and typical destinations for walking were largely absent. Destinations within walking distance included neighbors' homes and bodies of water. Views were mixed on whether shade, safety, dogs, and aesthetics affected decisions to exercise in their neighborhoods. Measures of neighborhood walkability in rural areas should acknowledge the small size of self-defined neighborhoods, that walking in rural areas is likely for leisure time exercise, and that some domains may not be relevant.

  13. Nearest neighbors by neighborhood counting.

    Science.gov (United States)

    Wang, Hui

    2006-06-01

    Finding nearest neighbors is a general idea that underlies many artificial intelligence tasks, including machine learning, data mining, natural language understanding, and information retrieval. This idea is explicitly used in the k-nearest neighbors algorithm (kNN), a popular classification method. In this paper, this idea is adopted in the development of a general methodology, neighborhood counting, for devising similarity functions. We turn our focus from neighbors to neighborhoods, a region in the data space covering the data point in question. To measure the similarity between two data points, we consider all neighborhoods that cover both data points. We propose to use the number of such neighborhoods as a measure of similarity. Neighborhood can be defined for different types of data in different ways. Here, we consider one definition of neighborhood for multivariate data and derive a formula for such similarity, called neighborhood counting measure or NCM. NCM was tested experimentally in the framework of kNN. Experiments show that NCM is generally comparable to VDM and its variants, the state-of-the-art distance functions for multivariate data, and, at the same time, is consistently better for relatively large k values. Additionally, NCM consistently outperforms HEOM (a mixture of Euclidean and Hamming distances), the "standard" and most widely used distance function for multivariate data. NCM has a computational complexity in the same order as the standard Euclidean distance function and NCM is task independent and works for numerical and categorical data in a conceptually uniform way. The neighborhood counting methodology is proven sound for multivariate data experimentally. We hope it will work for other types of data.

  14. Neighborhood Context and Immigrant Young Children's Development

    Science.gov (United States)

    Leventhal, Tama; Shuey, Elizabeth A.

    2014-01-01

    This study explored how neighborhood social processes and resources, relevant to immigrant families and immigrant neighborhoods, contribute to young children's behavioral functioning and achievement across diverse racial/ethnic groups. Data were drawn from the Project on Human Development in Chicago Neighborhoods, a neighborhood-based,…

  15. Childhood malnutrition in Egypt using geoadditive Gaussian and latent variable models.

    Science.gov (United States)

    Khatab, Khaled

    2010-04-01

    Major progress has been made over the last 30 years in reducing the prevalence of malnutrition amongst children less than 5 years of age in developing countries. However, approximately 27% of children under the age of 5 in these countries are still malnourished. This work focuses on the childhood malnutrition in one of the biggest developing countries, Egypt. This study examined the association between bio-demographic and socioeconomic determinants and the malnutrition problem in children less than 5 years of age using the 2003 Demographic and Health survey data for Egypt. In the first step, we use separate geoadditive Gaussian models with the continuous response variables stunting (height-for-age), underweight (weight-for-age), and wasting (weight-for-height) as indicators of nutritional status in our case study. In a second step, based on the results of the first step, we apply the geoadditive Gaussian latent variable model for continuous indicators in which the 3 measurements of the malnutrition status of children are assumed as indicators for the latent variable "nutritional status".

  16. NeighborHood

    OpenAIRE

    Corominola Ocaña, Víctor

    2015-01-01

    NeighborHood és una aplicació basada en el núvol, adaptable a qualsevol dispositiu (mòbil, tablet, desktop). L'objectiu d'aquesta aplicació és poder permetre als usuaris introduir a les persones del seu entorn més immediat i que aquestes persones siguin visibles per a la resta d'usuaris. NeighborHood es una aplicación basada en la nube, adaptable a cualquier dispositivo (móvil, tablet, desktop). El objetivo de esta aplicación es poder permitir a los usuarios introducir a las personas de su...

  17. Residential mobility and trajectories of adiposity among adolescents in urban and non-urban neighborhoods.

    Science.gov (United States)

    Jones, Antwan

    2015-04-01

    Using data from the 1994-2008 National Longitudinal Study of Adult Health (Add Health), this research examines the relationship between residential mobility and weight gain over time among urban and non-urban young adults. It is theorized that changes in residence act as a barrier to achieving an active lifestyle, which would increase an individual's body mass index (BMI) over time. Relying on linear mixed-effects growth curve models, the results indicate that mobility is protective against weight gain over time after controlling for sociodemographic characteristics. For young adults who are residentially stable in urban neighborhoods, increases in physical activity are associated with a linear decline in BMI. In non-urban areas where respondents are residentially mobile, body weight does not fluctuate as sedentary behavior increases. However, in those areas, weight increases as sedentary behavior increases for those who did not move. Overall, the results suggest that the effect of mobility on weight gain is partially due to the kind of health behaviors that one engages in as well as whether or not one lives in an urban area. Policies geared toward relocating residents (such as Moving to Opportunity), and neighborhood processes that can lead individuals to change residences (such as foreclosures or gentrification) may have adverse health effects depending on whether they are occurring in urban or non-urban areas.

  18. Vortices in Gaussian beams

    CSIR Research Space (South Africa)

    Roux, FS

    2009-01-01

    Full Text Available , t0)} = P(du, dv) {FR{g(u, v, t0)}} Replacement: u→ du = t− t0 i2 ∂ ∂u′ v → dv = t− t0 i2 ∂ ∂v′ CSIR National Laser Centre – p.13/30 Differentiation i.s.o integration Evaluate the integral over the Gaussian beam (once and for all). Then, instead... . Gaussian beams with vortex dipoles CSIR National Laser Centre – p.2/30 Gaussian beam notation Gaussian beam in normalised coordinates: g(u, v, t) = exp ( −u 2 + v2 1− it ) u = xω0 v = yω0 t = zρ ρ = piω20 λ ω0 — 1/e2 beam waist radius; ρ— Rayleigh range ω ω...

  19. Weighted OFDM for wireless multipath channels

    DEFF Research Database (Denmark)

    Prasad, Ramjee; Nikookar, H.

    2000-01-01

    In this paper the novel method of "weighted OFDM" is addressed. Different types of weighting factors (including Rectangular, Bartlett, Gaussian. Raised cosine, Half-sin and Shanon) are considered. The impact of weighting of OFDM on the peak-to-average power ratio (PAPR) is investigated by means...... of simulation and is compared for the above mentioned weighting factors. Results show that by weighting of the OFDM signal the PAPR reduces. Bit error performance of weighted multicarrier transmission over a multipath channel is also investigated. Results indicate that there is a trade off between PAPR...

  20. Work and Home Neighborhood Design and Physical Activity.

    Science.gov (United States)

    Carlson, Jordan A; Frank, Lawrence D; Ulmer, Jared; Conway, Terry L; Saelens, Brian E; Cain, Kelli L; Sallis, James F

    2018-01-01

    To investigate relations of perceived worksite neighborhood environments to total physical activity and active transportation, over and above home neighborhood built environments. Observational epidemiologic study. Baltimore, Maryland-Washington, DC, and Seattle-King County, Washington metropolitan areas. One thousand eighty-five adults (mean age = 45.0 [10.2]; 46% women) recruited from 32 neighborhoods stratified by high/low neighborhood income and walkability. The Neighborhood Environment Walkability Survey assessed perceptions of worksite and home neighborhood environments. Accelerometers assessed total moderate-to-vigorous physical activity (MVPA). The International Physical Activity Questionnaire assessed total active transportation and active transportation to and around work. Mixed-effects regression tested relations of home and worksite neighborhood environments to each physical activity outcome, adjusted for demographics. Home and worksite mixed land use and street connectivity had the most consistent positive associations with physical activity outcomes. Worksite traffic and pedestrian safety were also associated with multiple physical activity outcomes. The worksite neighborhood explained additional variance in physical activity outcomes than explained by the home neighborhood. Worksite and home neighborhood environments interacted in explaining active transportation to work, with the greatest impacts occurring when both neighborhoods were activity supportive. Both worksite and home neighborhood environments were independently related to total MVPA and active transportation. Community design policies should target improving the physical activity supportiveness of worksite neighborhood environments and integrating commercial and residential development.

  1. AUTONOMOUS GAUSSIAN DECOMPOSITION

    International Nuclear Information System (INIS)

    Lindner, Robert R.; Vera-Ciro, Carlos; Murray, Claire E.; Stanimirović, Snežana; Babler, Brian; Heiles, Carl; Hennebelle, Patrick; Goss, W. M.; Dickey, John

    2015-01-01

    We present a new algorithm, named Autonomous Gaussian Decomposition (AGD), for automatically decomposing spectra into Gaussian components. AGD uses derivative spectroscopy and machine learning to provide optimized guesses for the number of Gaussian components in the data, and also their locations, widths, and amplitudes. We test AGD and find that it produces results comparable to human-derived solutions on 21 cm absorption spectra from the 21 cm SPectral line Observations of Neutral Gas with the EVLA (21-SPONGE) survey. We use AGD with Monte Carlo methods to derive the H i line completeness as a function of peak optical depth and velocity width for the 21-SPONGE data, and also show that the results of AGD are stable against varying observational noise intensity. The autonomy and computational efficiency of the method over traditional manual Gaussian fits allow for truly unbiased comparisons between observations and simulations, and for the ability to scale up and interpret the very large data volumes from the upcoming Square Kilometer Array and pathfinder telescopes

  2. AUTONOMOUS GAUSSIAN DECOMPOSITION

    Energy Technology Data Exchange (ETDEWEB)

    Lindner, Robert R.; Vera-Ciro, Carlos; Murray, Claire E.; Stanimirović, Snežana; Babler, Brian [Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706 (United States); Heiles, Carl [Radio Astronomy Lab, UC Berkeley, 601 Campbell Hall, Berkeley, CA 94720 (United States); Hennebelle, Patrick [Laboratoire AIM, Paris-Saclay, CEA/IRFU/SAp-CNRS-Université Paris Diderot, F-91191 Gif-sur Yvette Cedex (France); Goss, W. M. [National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville, Socorro, NM 87801 (United States); Dickey, John, E-mail: rlindner@astro.wisc.edu [University of Tasmania, School of Maths and Physics, Private Bag 37, Hobart, TAS 7001 (Australia)

    2015-04-15

    We present a new algorithm, named Autonomous Gaussian Decomposition (AGD), for automatically decomposing spectra into Gaussian components. AGD uses derivative spectroscopy and machine learning to provide optimized guesses for the number of Gaussian components in the data, and also their locations, widths, and amplitudes. We test AGD and find that it produces results comparable to human-derived solutions on 21 cm absorption spectra from the 21 cm SPectral line Observations of Neutral Gas with the EVLA (21-SPONGE) survey. We use AGD with Monte Carlo methods to derive the H i line completeness as a function of peak optical depth and velocity width for the 21-SPONGE data, and also show that the results of AGD are stable against varying observational noise intensity. The autonomy and computational efficiency of the method over traditional manual Gaussian fits allow for truly unbiased comparisons between observations and simulations, and for the ability to scale up and interpret the very large data volumes from the upcoming Square Kilometer Array and pathfinder telescopes.

  3. Neighborhood Concentrated Disadvantage and Dating Violence among Urban Adolescents: The Mediating Role of Neighborhood Social Processes.

    Science.gov (United States)

    Garthe, Rachel C; Gorman-Smith, Deborah; Gregory, Joshua; E Schoeny, Michael

    2018-03-14

    The link between relationship violence and aspects of neighborhood concentrated disadvantage (e.g., percent of unemployed adults, percent of families below poverty level), has been established. However, the literature examining neighborhood social processes, including informal social control and social cohesion, in relation to adolescent dating violence has shown mixed results with a limited theoretical foundation and methodology. Using a social disorganization theoretical framework, this study examined the mediating role of these neighborhood social processes in the relation between concentrated disadvantage and adolescent dating violence within an urban context. Participants included 605 adult residents in 30 census tracts and 203 adolescents from neighborhoods on the West and South sides of Chicago. Neighborhood-level concentrated disadvantage was measured via Census data, adult residents reported on neighborhood social processes, and youth reported on dating violence. Informal social control was negatively associated with dating violence, and social cohesion was positively associated with dating violence. A multilevel mediation model showed that concentrated disadvantage was related to higher levels of dating violence via lower levels of informal social control. These results extend social disorganization theory to dating violence within an urban context, while also highlighting the important role of neighborhood processes on relationship violence. Implications for research and intervention programming are discussed. © Society for Community Research and Action 2018.

  4. Association between competitive food and beverage policies in elementary schools and childhood overweight/obesity trends: differences by neighborhood socioeconomic resources.

    Science.gov (United States)

    Sanchez-Vaznaugh, Emma V; Sánchez, Brisa N; Crawford, Patricia B; Egerter, Susan

    2015-05-01

    To our knowledge, few published studies have examined the influence of competitive food and beverage (CF&B) policies on student weight outcomes; none have investigated disparities in the influence of CF&B policies on children's body weight by school neighborhood socioeconomic resources. To investigate whether the association between CF&B policies and population-level trends in childhood overweight/obesity differed by school neighborhood income and education levels. This cross-sectional study, from July 2013 to October 2014, compared overweight/obesity prevalence trends before (2001-2005) and after (2006-2010) implementation of CF&B policies in public elementary schools in California. The study included 2 700 880 fifth-grade students in 5362 public schools from 2001 to 2010. California CF&B policies (effective July 1, 2004, and July 1, 2007) and school neighborhood income and education levels. Overweight/obesity defined as a body mass index at or greater than the 85th percentile for age and sex. Overall rates of overweight/obesity ranged from 43.5% in 2001 to 45.8% in 2010. Compared with the period before the introduction of CF&B policies, overweight/obesity trends changed in a favorable direction after the policies took effect (2005-2010); these changes occurred for all children across all school neighborhood socioeconomic levels. In the postpolicy period, these trends differed by school neighborhood socioeconomic advantage. From 2005-2010, trends in overweight/obesity prevalence leveled off among students at schools in socioeconomically disadvantaged neighborhoods but declined in socioeconomically advantaged neighborhoods. Students in the lowest-income neighborhoods experienced zero or near zero change in the odds of overweight/obesity over time: the annual percentage change in overweight/obesity odds was 0.1% for females (95% CI, -0.7 to 0.9) and -0.3% for males (95% CI, -1.1 to 0.5). In contrast, in the highest-income neighborhoods, the annual percentage

  5. Comprehensive Neighborhood Portraits and Child Asthma Disparities.

    Science.gov (United States)

    Kranjac, Ashley W; Kimbro, Rachel T; Denney, Justin T; Osiecki, Kristin M; Moffett, Brady S; Lopez, Keila N

    2017-07-01

    Objectives Previous research has established links between child, family, and neighborhood disadvantages and child asthma. We add to this literature by first characterizing neighborhoods in Houston, TX by demographic, economic, and air quality characteristics to establish differences in pediatric asthma diagnoses across neighborhoods. Second, we identify the relative risk of social, economic, and environmental risk factors for child asthma diagnoses. Methods We geocoded and linked electronic pediatric medical records to neighborhood-level social and economic indicators. Using latent profile modeling techniques, we identified Advantaged, Middle-class, and Disadvantaged neighborhoods. We then used a modified version of the Blinder-Oaxaca regression decomposition method to examine differences in asthma diagnoses across children in these different neighborhoods. Results Both compositional (the characteristics of the children and the ambient air quality in the neighborhood) and associational (the relationship between child and air quality characteristics and asthma) differences within the distinctive neighborhood contexts influence asthma outcomes. For example, unequal exposure to PM 2.5 and O 3 among children in Disadvantaged and Middle-class neighborhoods contribute to asthma diagnosis disparities within these contexts. For children in Disadvantaged and Advantaged neighborhoods, associational differences between racial/ethnic and socioeconomic characteristics and asthma diagnoses explain a significant proportion of the gap. Conclusions for Practice Our results provide evidence that differential exposure to pollution and protective factors associated with non-Hispanic White children and children from affluent families contribute to asthma disparities between neighborhoods. Future researchers should consider social and racial inequalities as more proximate drivers, not merely as associated, with asthma disparities in children.

  6. Detecting the presence of a magnetic field under Gaussian and non-Gaussian noise by adaptive measurement

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuan-Mei; Li, Jun-Gang, E-mail: jungl@bit.edu.cn; Zou, Jian

    2017-06-15

    Highlights: • Adaptive measurement strategy is used to detect the presence of a magnetic field. • Gaussian Ornstein–Uhlenbeck noise and non-Gaussian noise have been considered. • Weaker magnetic fields may be more easily detected than some stronger ones. - Abstract: By using the adaptive measurement method we study how to detect whether a weak magnetic field is actually present or not under Gaussian noise and non-Gaussian noise. We find that the adaptive measurement method can effectively improve the detection accuracy. For the case of Gaussian noise, we find the stronger the magnetic field strength, the easier for us to detect the magnetic field. Counterintuitively, for non-Gaussian noise, some weaker magnetic fields are more likely to be detected rather than some stronger ones. Finally, we give a reasonable physical interpretation.

  7. Neighborhood Influences on Perceived Social Support Among Parents: Findings from the Project on Human Development in Chicago Neighborhoods

    Science.gov (United States)

    Tendulkar, Shalini A.; Koenen, Karestan C.; Dunn, Erin C.; Buka, Stephen; Subramanian, S. V.

    2012-01-01

    Background Social support is frequently linked to positive parenting behavior. Similarly, studies increasingly show a link between neighborhood residential environment and positive parenting behavior. However, less is known about how the residential environment influences parental social support. To address this gap, we examine the relationship between neighborhood concentrated disadvantage and collective efficacy and the level and change in parental caregiver perceptions of non-familial social support. Methodology/Principal Findings The data for this study came from three data sources, the Project on Human Development in Chicago Neighborhoods (PHDCN) Study's Longitudinal Cohort Survey of caregivers and their offspring, a Community Survey of adult residents in these same neighborhoods and the 1990 Census. Social support is measured at Wave 1 and Wave 3 and neighborhood characteristics are measured at Wave 1. Multilevel linear regression models are fit. The results show that neighborhood collective efficacy is a significant (ß = .04; SE = .02; p = .03), predictor of the positive change in perceived social support over a 7 year period, however, not of the level of social support, adjusting for key compositional variables and neighborhood concentrated disadvantage. In contrast concentrated neighborhood disadvantage is not a significant predictor of either the level or change in social support. Conclusion Our finding suggests that neighborhood collective efficacy may be important for inducing the perception of support from friends in parental caregivers over time. PMID:22493683

  8. Neighborhood influences on perceived social support among parents: findings from the project on human development in Chicago neighborhoods.

    Science.gov (United States)

    Tendulkar, Shalini A; Koenen, Karestan C; Dunn, Erin C; Buka, Stephen; Subramanian, S V

    2012-01-01

    Social support is frequently linked to positive parenting behavior. Similarly, studies increasingly show a link between neighborhood residential environment and positive parenting behavior. However, less is known about how the residential environment influences parental social support. To address this gap, we examine the relationship between neighborhood concentrated disadvantage and collective efficacy and the level and change in parental caregiver perceptions of non-familial social support. The data for this study came from three data sources, the Project on Human Development in Chicago Neighborhoods (PHDCN) Study's Longitudinal Cohort Survey of caregivers and their offspring, a Community Survey of adult residents in these same neighborhoods and the 1990 Census. Social support is measured at Wave 1 and Wave 3 and neighborhood characteristics are measured at Wave 1. Multilevel linear regression models are fit. The results show that neighborhood collective efficacy is a significant (ß = .04; SE = .02; p = .03), predictor of the positive change in perceived social support over a 7 year period, however, not of the level of social support, adjusting for key compositional variables and neighborhood concentrated disadvantage. In contrast concentrated neighborhood disadvantage is not a significant predictor of either the level or change in social support. Our finding suggests that neighborhood collective efficacy may be important for inducing the perception of support from friends in parental caregivers over time.

  9. Schools, Neighborhood Risk Factors, and Crime

    Science.gov (United States)

    Willits, Dale; Broidy, Lisa; Denman, Kristine

    2013-01-01

    Prior research has identified a link between schools (particularly high schools) and neighborhood crime rates. However, it remains unclear whether the relationship between schools and crime is a reflection of other criminogenic dynamics at the neighborhood level or whether schools influence neighborhood crime patterns independently of other…

  10. Geometry of Gaussian quantum states

    International Nuclear Information System (INIS)

    Link, Valentin; Strunz, Walter T

    2015-01-01

    We study the Hilbert–Schmidt measure on the manifold of mixed Gaussian states in multi-mode continuous variable quantum systems. An analytical expression for the Hilbert–Schmidt volume element is derived. Its corresponding probability measure can be used to study typical properties of Gaussian states. It turns out that although the manifold of Gaussian states is unbounded, an ensemble of Gaussian states distributed according to this measure still has a normalizable distribution of symplectic eigenvalues, from which unitarily invariant properties can be obtained. By contrast, we find that for an ensemble of one-mode Gaussian states based on the Bures measure the corresponding distribution cannot be normalized. As important applications, we determine the distribution and the mean value of von Neumann entropy and purity for the Hilbert–Schmidt measure. (paper)

  11. Internet Bad Neighborhoods Aggregation

    NARCIS (Netherlands)

    Moreira Moura, Giovane; Sadre, R.; Sperotto, Anna; Pras, Aiko; Paschoal Gaspary, L.; De Turk, Filip

    Internet Bad Neighborhoods have proven to be an innovative approach for fighting spam. They have also helped to understand how spammers are distributed on the Internet. In our previous works, the size of each bad neighborhood was fixed to a /24 subnetwork. In this paper, however, we investigate if

  12. Negative life events vary by neighborhood and mediate the relation between neighborhood context and psychological well-being.

    Directory of Open Access Journals (Sweden)

    Katherine King

    Full Text Available Researchers have speculated that negative life events are more common in troubled neighborhoods, amplifying adverse effects on health. Using a clustered representative sample of Chicago residents (2001-03; n = 3,105 from the Chicago Community Adult Health Survey, we provide the first documentation that negative life events are highly geographically clustered compared to health outcomes. Associations between neighborhood context and negative life events were also found to vary by event type. We then demonstrate the power of a contextualized approach by testing path models in which life events mediate the relation between neighborhood characteristics and health outcomes, including self-rated health, anxiety, and depression. The indirect paths between neighborhood conditions and health through negative life event exposure are highly significant and large compared to the direct paths from neighborhood conditions to health. Our results indicate that neighborhood conditions can have acute as well as chronic effects on health, and that negative life events are a powerful mechanism by which context may influence health.

  13. Negative life events vary by neighborhood and mediate the relation between neighborhood context and psychological well-being.

    Science.gov (United States)

    King, Katherine; Ogle, Christin

    2014-01-01

    Researchers have speculated that negative life events are more common in troubled neighborhoods, amplifying adverse effects on health. Using a clustered representative sample of Chicago residents (2001-03; n = 3,105) from the Chicago Community Adult Health Survey, we provide the first documentation that negative life events are highly geographically clustered compared to health outcomes. Associations between neighborhood context and negative life events were also found to vary by event type. We then demonstrate the power of a contextualized approach by testing path models in which life events mediate the relation between neighborhood characteristics and health outcomes, including self-rated health, anxiety, and depression. The indirect paths between neighborhood conditions and health through negative life event exposure are highly significant and large compared to the direct paths from neighborhood conditions to health. Our results indicate that neighborhood conditions can have acute as well as chronic effects on health, and that negative life events are a powerful mechanism by which context may influence health.

  14. Quantum steering of multimode Gaussian states by Gaussian measurements: monogamy relations and the Peres conjecture

    International Nuclear Information System (INIS)

    Ji, Se-Wan; Nha, Hyunchul; Kim, M S

    2015-01-01

    It is a topic of fundamental and practical importance how a quantum correlated state can be reliably distributed through a noisy channel for quantum information processing. The concept of quantum steering recently defined in a rigorous manner is relevant to study it under certain circumstances and here we address quantum steerability of Gaussian states to this aim. In particular, we attempt to reformulate the criterion for Gaussian steering in terms of local and global purities and show that it is sufficient and necessary for the case of steering a 1-mode system by an N-mode system. It subsequently enables us to reinforce a strong monogamy relation under which only one party can steer a local system of 1-mode. Moreover, we show that only a negative partial-transpose state can manifest quantum steerability by Gaussian measurements in relation to the Peres conjecture. We also discuss our formulation for the case of distributing a two-mode squeezed state via one-way quantum channels making dissipation and amplification effects, respectively. Finally, we extend our approach to include non-Gaussian measurements, more precisely, all orders of higher-order squeezing measurements, and find that this broad set of non-Gaussian measurements is not useful to demonstrate steering for Gaussian states beyond Gaussian measurements. (paper)

  15. Efficient weighting strategy for enhancing synchronizability of complex networks

    Science.gov (United States)

    Wang, Youquan; Yu, Feng; Huang, Shucheng; Tu, Juanjuan; Chen, Yan

    2018-04-01

    Networks with high propensity to synchronization are desired in many applications ranging from biology to engineering. In general, there are two ways to enhance the synchronizability of a network: link rewiring and/or link weighting. In this paper, we propose a new link weighting strategy based on the concept of the neighborhood subgroup. The neighborhood subgroup of a node i through node j in a network, i.e. Gi→j, means that node u belongs to Gi→j if node u belongs to the first-order neighbors of j (not include i). Our proposed weighting schema used the local and global structural properties of the networks such as the node degree, betweenness centrality and closeness centrality measures. We applied the method on scale-free and Watts-Strogatz networks of different structural properties and show the good performance of the proposed weighting scheme. Furthermore, as model networks cannot capture all essential features of real-world complex networks, we considered a number of undirected and unweighted real-world networks. To the best of our knowledge, the proposed weighting strategy outperformed the previously published weighting methods by enhancing the synchronizability of these real-world networks.

  16. Neighborhood perceptions and allostatic load

    DEFF Research Database (Denmark)

    van Deurzen, Ioana; Rod, Naja Hulvej; Christensen, Ulla

    2016-01-01

    An influential argument explaining why living in certain neighborhoods can become harmful to one's health maintains that individuals can perceive certain characteristics of the neighborhood as threatening and the prolonged exposure to a threatening environment could induce chronic stress. Following...... this line of argumentation, in the present study we test whether subjective perceptions of neighborhood characteristics relate to an objective measure of stress-related physiological functioning, namely allostatic load (AL). We use a large dataset of 5280 respondents living in different regions of Denmark...... and we account for two alternative mechanisms, i.e., the objective characteristics of the living environment and the socio-economic status of individuals. Our results support the chronic stress mechanisms linking neighborhood quality to health. Heightened perceptions of disorder and pollution were found...

  17. Neighborhood influences on perceived social support among parents: findings from the project on human development in Chicago neighborhoods.

    Directory of Open Access Journals (Sweden)

    Shalini A Tendulkar

    Full Text Available BACKGROUND: Social support is frequently linked to positive parenting behavior. Similarly, studies increasingly show a link between neighborhood residential environment and positive parenting behavior. However, less is known about how the residential environment influences parental social support. To address this gap, we examine the relationship between neighborhood concentrated disadvantage and collective efficacy and the level and change in parental caregiver perceptions of non-familial social support. METHODOLOGY/PRINCIPAL FINDINGS: The data for this study came from three data sources, the Project on Human Development in Chicago Neighborhoods (PHDCN Study's Longitudinal Cohort Survey of caregivers and their offspring, a Community Survey of adult residents in these same neighborhoods and the 1990 Census. Social support is measured at Wave 1 and Wave 3 and neighborhood characteristics are measured at Wave 1. Multilevel linear regression models are fit. The results show that neighborhood collective efficacy is a significant (ß = .04; SE = .02; p = .03, predictor of the positive change in perceived social support over a 7 year period, however, not of the level of social support, adjusting for key compositional variables and neighborhood concentrated disadvantage. In contrast concentrated neighborhood disadvantage is not a significant predictor of either the level or change in social support. CONCLUSION: Our finding suggests that neighborhood collective efficacy may be important for inducing the perception of support from friends in parental caregivers over time.

  18. Neighborhoods, US, 2017, Zillow, SEGS

    Data.gov (United States)

    U.S. Environmental Protection Agency — This web service depicts nearly 17,000 neighborhood boundaries in over 650 U.S. cities. Zillow created the neighborhood boundaries and is sharing them with the...

  19. Efficient Kernel-Based Ensemble Gaussian Mixture Filtering

    KAUST Repository

    Liu, Bo

    2015-11-11

    We consider the Bayesian filtering problem for data assimilation following the kernel-based ensemble Gaussian-mixture filtering (EnGMF) approach introduced by Anderson and Anderson (1999). In this approach, the posterior distribution of the system state is propagated with the model using the ensemble Monte Carlo method, providing a forecast ensemble that is then used to construct a prior Gaussian-mixture (GM) based on the kernel density estimator. This results in two update steps: a Kalman filter (KF)-like update of the ensemble members and a particle filter (PF)-like update of the weights, followed by a resampling step to start a new forecast cycle. After formulating EnGMF for any observational operator, we analyze the influence of the bandwidth parameter of the kernel function on the covariance of the posterior distribution. We then focus on two aspects: i) the efficient implementation of EnGMF with (relatively) small ensembles, where we propose a new deterministic resampling strategy preserving the first two moments of the posterior GM to limit the sampling error; and ii) the analysis of the effect of the bandwidth parameter on contributions of KF and PF updates and on the weights variance. Numerical results using the Lorenz-96 model are presented to assess the behavior of EnGMF with deterministic resampling, study its sensitivity to different parameters and settings, and evaluate its performance against ensemble KFs. The proposed EnGMF approach with deterministic resampling suggests improved estimates in all tested scenarios, and is shown to require less localization and to be less sensitive to the choice of filtering parameters.

  20. Treatment of non-Gaussian tails of multiple Coulomb scattering in track fitting with a Gaussian-sum filter

    International Nuclear Information System (INIS)

    Strandlie, A.; Wroldsen, J.

    2006-01-01

    If any of the probability densities involved in track fitting deviate from the Gaussian assumption, it is plausible that a non-linear estimator which better takes the actual shape of the distribution into account can do better. One such non-linear estimator is the Gaussian-sum filter, which is adequate if the distributions under consideration can be approximated by Gaussian mixtures. The main purpose of this paper is to present a Gaussian-sum filter for track fitting, based on a two-component approximation of the distribution of angular deflections due to multiple scattering. In a simulation study within a linear track model the Gaussian-sum filter is shown to be a competitive alternative to the Kalman filter. Scenarios at various momenta and with various maximum number of components in the Gaussian-sum filter are considered. Particularly at low momenta the Gaussian-sum filter yields a better estimate of the uncertainties than the Kalman filter, and it is also slightly more precise than the latter

  1. Palm distributions for log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus Plenge

    2017-01-01

    This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new...... result is used to study functional summaries for log Gaussian Cox processes....

  2. High-Order Local Pooling and Encoding Gaussians Over a Dictionary of Gaussians.

    Science.gov (United States)

    Li, Peihua; Zeng, Hui; Wang, Qilong; Shiu, Simon C K; Zhang, Lei

    2017-07-01

    Local pooling (LP) in configuration (feature) space proposed by Boureau et al. explicitly restricts similar features to be aggregated, which can preserve as much discriminative information as possible. At the time it appeared, this method combined with sparse coding achieved competitive classification results with only a small dictionary. However, its performance lags far behind the state-of-the-art results as only the zero-order information is exploited. Inspired by the success of high-order statistical information in existing advanced feature coding or pooling methods, we make an attempt to address the limitation of LP. To this end, we present a novel method called high-order LP (HO-LP) to leverage the information higher than the zero-order one. Our idea is intuitively simple: we compute the first- and second-order statistics per configuration bin and model them as a Gaussian. Accordingly, we employ a collection of Gaussians as visual words to represent the universal probability distribution of features from all classes. Our problem is naturally formulated as encoding Gaussians over a dictionary of Gaussians as visual words. This problem, however, is challenging since the space of Gaussians is not a Euclidean space but forms a Riemannian manifold. We address this challenge by mapping Gaussians into the Euclidean space, which enables us to perform coding with common Euclidean operations rather than complex and often expensive Riemannian operations. Our HO-LP preserves the advantages of the original LP: pooling only similar features and using a small dictionary. Meanwhile, it achieves very promising performance on standard benchmarks, with either conventional, hand-engineered features or deep learning-based features.

  3. Effects of Neighborhood Walkability on Physical Activity and Sedentary Behavior Long-Term Post-Bariatric Surgery.

    Science.gov (United States)

    Reid, Ryan E R; Carver, Tamara E; Reid, Tyler G R; Picard-Turcot, Marie-Aude; Andersen, Kathleen M; Christou, Nicolas V; Andersen, Ross E

    2017-06-01

    ᅟ: Chronic inactivity and weight regain are serious health concerns following bariatric surgery. Neighborhood walkability is associated with higher physical activity and lower obesity rates in normal weight populations. Explore the influence of neighborhood walkability on physical activity and sedentarism among long-term post-bariatric surgery patients. Fifty-eight adults aged 50.5 ± 9.1 years, with a BMI of 34.6 ± 9.7 kg/m 2 having undergone surgery 9.8 ± 3.15 years earlier participated in this study. Participants were asked to wear an ActivPAL™ tri-axial accelerometer attached to their mid-thigh for 7-consecutive days, 24 hours/day. The sample was separated into those that live in Car-Dependent (n = 23), Somewhat Walkable (n = 14), Very Walkable (n = 16), and Walker's Paradise (n = 5) neighborhoods as defined using Walk Score®. ANCOVA was performed comparing Walk Score® categories on steps and sedentary time controlling for age and sex. Neighborhood walkability did not influence either daily steps (F (3, 54) = 0.921, p = 0.437) or sedentary time (F (3, 54) = 0.465, p = 0.708), Car-Dependent (6359 ± 2712 steps, 9.54 ± 2.46 hrs), Somewhat Walkable (6563 ± 2989 steps, 9.07 ± 2.70 hrs), Very Walkable (5261 ± 2255 steps, 9.97 ± 2.06 hrs), and Walker's Paradise (6901 ± 1877 steps, 10.14 ± 0.815 hrs). Walkability does not appear to affect sedentary time or physical activity long-term post-surgery. As the built-environment does not seem to influence activity, sedentarism, or obesity as it does with a normal weight population, work needs to be done to tailor physical activity programming after bariatric surgery.

  4. Neighborhood Disadvantage and Physical Function: The Contributions of Neighborhood-Level Perceptions of Safety From Crime and Walking for Recreation.

    Science.gov (United States)

    Loh, Venurs H Y; Rachele, Jerome N; Brown, Wendy J; Ghani, Fatima; Turrell, Gavin

    2018-04-20

    Residents of more socioeconomically disadvantaged neighborhoods are more likely to report poorer physical function, although the reasons for this remain unknown. It is possible that neighborhood-level perceptions of safety from crime contribute to this relationship through its association with walking for recreation. Data were obtained from the fourth wave (collected in 2013) of the HABITAT (How Areas in Brisbane Influence HealTh and AcTivity) multilevel longitudinal study of middle- to older-aged adults (46-74 y) residing in 200 neighborhoods in Brisbane, Australia. The data were analyzed separately for men (n = 2190) and women (n = 2977) using multilevel models. Residents of the most disadvantaged neighborhoods had poorer physical function, perceived their neighborhoods to be less safe from crime, and do less walking for recreation. These factors accounted for differences in physical function between disadvantaged and advantaged neighborhoods (24% for men and 25% for women). This study highlights the importance of contextual characteristics, through their associations with behaviors, that can have in explaining the relationship between neighborhood disadvantage and physical function. Interventions aimed at improving neighborhood safety integrated with supportive environments for physical activity may have positive impact on physical function among all socioeconomic groups.

  5. Conduct Disorder and Neighborhood Effects.

    Science.gov (United States)

    Jennings, Wesley G; Perez, Nicholas M; Reingle Gonzalez, Jennifer M

    2018-05-07

    There has been a considerable amount of scholarly attention to the relationship between neighborhood effects and conduct disorder, particularly in recent years. Having said this, it has been nearly two decades since a comprehensive synthesis of this literature has been conducted. Relying on a detailed and comprehensive search strategy and inclusion criteria, this article offers a systematic and interdisciplinary review of 47 empirical studies that have examined neighborhood effects and conduct disorder. Described results suggest that there are generally robust linkages between adverse neighborhood factors and conduct disorder and externalizing behavior problems, as 67 of the 93 (72.04%) effect sizes derived from these studies yielded statistically significant neighborhood effects. The review also identifies salient mediating and moderating influences. It discusses study limitations and directions for future research as well.

  6. Neighborhood Ethnic Density as an Explanation for the Academic Achievement of Ethnic Minority Youth Placed in Neighborhood Disadvantage

    Science.gov (United States)

    Madyun, Na'im; Lee, Moosung

    2010-01-01

    The underachievement of ethnic minority youth from disadvantaged neighborhoods is a pervasive educational issue this nation is facing. Based on an ecological perspective, we examined the contextual effects of neighborhood ethnic density and neighborhood disadvantage on the academic achievement of Hmong immigrant youths. Utilizing hierarchical…

  7. Accelerating Sequential Gaussian Simulation with a constant path

    Science.gov (United States)

    Nussbaumer, Raphaël; Mariethoz, Grégoire; Gravey, Mathieu; Gloaguen, Erwan; Holliger, Klaus

    2018-03-01

    Sequential Gaussian Simulation (SGS) is a stochastic simulation technique commonly employed for generating realizations of Gaussian random fields. Arguably, the main limitation of this technique is the high computational cost associated with determining the kriging weights. This problem is compounded by the fact that often many realizations are required to allow for an adequate uncertainty assessment. A seemingly simple way to address this problem is to keep the same simulation path for all realizations. This results in identical neighbourhood configurations and hence the kriging weights only need to be determined once and can then be re-used in all subsequent realizations. This approach is generally not recommended because it is expected to result in correlation between the realizations. Here, we challenge this common preconception and make the case for the use of a constant path approach in SGS by systematically evaluating the associated benefits and limitations. We present a detailed implementation, particularly regarding parallelization and memory requirements. Extensive numerical tests demonstrate that using a constant path allows for substantial computational gains with very limited loss of simulation accuracy. This is especially the case for a constant multi-grid path. The computational savings can be used to increase the neighbourhood size, thus allowing for a better reproduction of the spatial statistics. The outcome of this study is a recommendation for an optimal implementation of SGS that maximizes accurate reproduction of the covariance structure as well as computational efficiency.

  8. Geometrical tile design for complex neighborhoods.

    Science.gov (United States)

    Czeizler, Eugen; Kari, Lila

    2009-01-01

    Recent research has showed that tile systems are one of the most suitable theoretical frameworks for the spatial study and modeling of self-assembly processes, such as the formation of DNA and protein oligomeric structures. A Wang tile is a unit square, with glues on its edges, attaching to other tiles and forming larger and larger structures. Although quite intuitive, the idea of glues placed on the edges of a tile is not always natural for simulating the interactions occurring in some real systems. For example, when considering protein self-assembly, the shape of a protein is the main determinant of its functions and its interactions with other proteins. Our goal is to use geometric tiles, i.e., square tiles with geometrical protrusions on their edges, for simulating tiled paths (zippers) with complex neighborhoods, by ribbons of geometric tiles with simple, local neighborhoods. This paper is a step toward solving the general case of an arbitrary neighborhood, by proposing geometric tile designs that solve the case of a "tall" von Neumann neighborhood, the case of the f-shaped neighborhood, and the case of a 3 x 5 "filled" rectangular neighborhood. The techniques can be combined and generalized to solve the problem in the case of any neighborhood, centered at the tile of reference, and included in a 3 x (2k + 1) rectangle.

  9. Breaking Gaussian incompatibility on continuous variable quantum systems

    Energy Technology Data Exchange (ETDEWEB)

    Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Kiukas, Jukka, E-mail: jukka.kiukas@aber.ac.uk [Department of Mathematics, Aberystwyth University, Penglais, Aberystwyth, SY23 3BZ (United Kingdom); Schultz, Jussi, E-mail: jussi.schultz@gmail.com [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)

    2015-08-15

    We characterise Gaussian quantum channels that are Gaussian incompatibility breaking, that is, transform every set of Gaussian measurements into a set obtainable from a joint Gaussian observable via Gaussian postprocessing. Such channels represent local noise which renders measurements useless for Gaussian EPR-steering, providing the appropriate generalisation of entanglement breaking channels for this scenario. Understanding the structure of Gaussian incompatibility breaking channels contributes to the resource theory of noisy continuous variable quantum information protocols.

  10. Neighborhood and Network Disadvantage among Urban Renters

    Directory of Open Access Journals (Sweden)

    Matthew Desmond

    2015-06-01

    Full Text Available Drawing on novel survey data, this study maps the distribution of neighborhood and network disadvantage in a population of Milwaukee renters and evaluates the relationship between each disadvantage and multiple social and health outcomes. We find that many families live in neighborhoods with above average disadvantage but are embedded in networks with below average disadvantage, and vice versa. Neighborhood (but not network disadvantage is associated with lower levels of neighborly trust but also with higher levels of community support (e.g., providing neighbors with food. Network (but not neighborhood disadvantage is associated with lower levels of civic engagement. Asthma and diabetes are associated exclusively with neighborhood disadvantage, but depression is associated exclusively with network disadvantage. These findings imply that some social problems may be better addressed by neighborhood interventions and others by network interventions.

  11. Functional Interpretation of Neighborhood Public Spaces in Terms of Identity

    Directory of Open Access Journals (Sweden)

    Hamid Majedi

    2015-03-01

    Full Text Available The aim of this article is to evaluate the effect of neighborhood public space transformation due to rapid urbanization in Tehran since 1960s, on the formation of neighborhood identity. In order to find the role of public spaces in enhancing neighborhood identities, two middle class neighborhoods with different spatial organizations are compared with each other: Nazi Abad a planned neighborhood and Mehran a typical unplanned neighborhood which developed through rapid urbanization.   Next, the effect of neighborhood public spaces on neighborhood inhabitants is evaluated from two perspectives: Perceptual dimension and social dimension. The findings indicate that planned spatial organization and various neighborhood public spaces result in stronger neighborhood identity. It enhances both perceptual dimension of neighborhood identity(place attachment and its social dimension (sense of community. In contrast unplanned spatial organization which is the typical feature of Tehran neighborhoods leads to weak neighborhood identity.

  12. Aging in Neighborhoods Differing in Walkability and Income: Associations with Physical Activity and Obesity in Older Adults

    Science.gov (United States)

    King, Abby C.; Sallis, James F.; Frank, Lawrence D.; Saelens, Brian E.; Cain, Kelli; Conway, Terry L.; Chapman, James E.; Ahn, David K.; Kerr, Jacqueline

    2011-01-01

    While there is a growing literature on the relations between neighborhood design and health factors such as physical activity and obesity, less focus has been placed on older adults, who may be particularly vulnerable to environmental influences. This study evaluates the relations among objectively measured neighborhood design, mobility impairment, and physical activity and body weight in two U.S. regional samples of community dwelling older adults living in neighborhoods differing in walkability and income levels. An observational design involving two time points six months apart was employed between 2005–2008. U.S. Census block groups in Seattle-King County, Washington and Baltimore. Maryland-Washington DC regions were selected via geographic information systems to maximize variability in walkability and income. Participants were 719 adults ages 66 years and older who were able to complete surveys in English and walk at least 10 feet continuously. Measurements included reported walking or bicycling for errands (i.e., transport activity) and other outdoor aerobic activities measured via the CHAMPS questionnaire: accelerometry-based moderate-to-vigorous physical activity; reported body mass index; and reported lower-extremity mobility impairment measured via the Late-Life Function and Disability Instrument. Across regions, time, and neighborhood income, older adults living in more walkable neighborhoods had more transport activity and moderate-to- vigorous physical activity and lower body mass index relative to those living in less walkable neighborhoods. The most mobility-impaired adults living in more walkable neighborhoods reported transport activity levels that were similar to less mobility-impaired adults living in less walkable neighborhoods. The results add to the small literature aimed at understanding how neighborhood design may influence physical activity and related aspects of health linked with day-to-day function and independence as people age. PMID

  13. The impact of neighborhood walkability on walking: does it differ across adult life stage and does neighborhood buffer size matter?

    Science.gov (United States)

    Villanueva, Karen; Knuiman, Matthew; Nathan, Andrea; Giles-Corti, Billie; Christian, Hayley; Foster, Sarah; Bull, Fiona

    2014-01-01

    We explored the impact of neighborhood walkability on young adults, early-middle adults, middle-aged adults, and older adults' walking across different neighborhood buffers. Participants completed the Western Australian Health and Wellbeing Surveillance System Survey (2003-2009) and were allocated a neighborhood walkability score at 200m, 400m, 800m, and 1600m around their home. We found little difference in strength of associations across neighborhood size buffers for all life stages. We conclude that neighborhood walkability supports more walking regardless of adult life stage and is relevant for small (e.g., 200m) and larger (e.g., 1600m) neighborhood buffers. © 2013 The Authors. Published by Elsevier Ltd All rights reserved.

  14. Young children in urban areas: Links among neighborhood characteristics, weight status, outdoor play, and television watching

    Science.gov (United States)

    Kimbro, Rachel Tolbert; Brooks-Gunn, Jeanne; McLanahan, Sara

    2011-01-01

    Although research consistently demonstrates a link between residential context and physical activity for adults and adolescents, less is known about young children’s physical activity. Using data from the U.S. Fragile Families and Child Wellbeing Study (N=1822, 51% male), we explored whether outdoor play and television watching were associated with children’s body mass indexes (BMIs) at age five using OLS regression models, controlling for a wide array of potential confounders, including maternal BMI. We also tested whether subjective and objective neighborhood measures - socioeconomic status (from U.S. Census tract data), type of dwelling, perceived collective efficacy, and interviewer-assessed physical disorder of the immediate environment outside the home -were associated with children’s activities, using negative binomial regression models. Overall, 19% of the sample were overweight (between the 85th and 95th percentiles), and 16% were obese (≥95th percentile). Hours of outdoor play were negatively associated with BMI, and hours of television were positively associated with BMI. Moreover, a ratio of outdoor play to television time was a significant predictor of BMI. Higher maternal perceptions of neighborhood collective efficacy were associated with more hours of outdoor play, fewer hours of television viewing, and more trips to a park or playground. In addition, we found that neighborhood physical disorder was associated with both more outdoor play and more television watching. Finally, contrary to expectations, we found that children living in public housing had significantly more hours of outdoor play and watched more television, than other children. We hypothesize that poorer children may have more unstructured time, which they fill with television time but also with outdoor play time; and that children in public housing may be likely to have access to play areas on the grounds of their housing facilities. PMID:21324574

  15. Young children in urban areas: links among neighborhood characteristics, weight status, outdoor play, and television watching.

    Science.gov (United States)

    Kimbro, Rachel Tolbert; Brooks-Gunn, Jeanne; McLanahan, Sara

    2011-03-01

    Although research consistently demonstrates a link between residential context and physical activity for adults and adolescents, less is known about young children's physical activity. Using data from the U.S. Fragile Families and Child Wellbeing Study (N=1822, 51% male), we explored whether outdoor play and television watching were associated with children's body mass indexes (BMIs) at age five using OLS regression models, controlling for a wide array of potential confounders, including maternal BMI. We also tested whether subjective and objective neighborhood measures - socioeconomic status (from U.S. Census tract data), type of dwelling, perceived collective efficacy, and interviewer-assessed physical disorder of the immediate environment outside the home - were associated with children's activities, using negative binomial regression models. Overall, 19% of the sample were overweight (between the 85th and 95th percentiles), and 16% were obese (≥ 95th percentile). Hours of outdoor play were negatively associated with BMI, and hours of television were positively associated with BMI. Moreover, a ratio of outdoor play to television time was a significant predictor of BMI. Higher maternal perceptions of neighborhood collective efficacy were associated with more hours of outdoor play, fewer hours of television viewing, and more trips to a park or playground. In addition, we found that neighborhood physical disorder was associated with both more outdoor play and more television watching. Finally, contrary to expectations, we found that children living in public housing had significantly more hours of outdoor play and watched more television, than other children. We hypothesize that poorer children may have more unstructured time, which they fill with television time but also with outdoor play time; and that children in public housing may be likely to have access to play areas on the grounds of their housing facilities. Copyright © 2011 Elsevier Ltd. All rights

  16. Simultaneous masking additivity for short Gaussian-shaped tones: spectral effects.

    Science.gov (United States)

    Laback, Bernhard; Necciari, Thibaud; Balazs, Peter; Savel, Sophie; Ystad, Sølvi

    2013-08-01

    Laback et al. [(2011). J. Acoust. Soc. Am. 129, 888-897] investigated the additivity of nonsimultaneous masking using short Gaussian-shaped tones as maskers and target. The present study involved Gaussian stimuli to measure the additivity of simultaneous masking for combinations of up to four spectrally separated maskers. According to most basilar membrane measurements, the maskers should be processed linearly at the characteristic frequency (CF) of the target. Assuming also compression of the target, all masker combinations should produce excess masking (exceeding linear additivity). The results for a pair of maskers flanking the target indeed showed excess masking. The amount of excess masking could be predicted by a model assuming summation of masker-evoked excitations in intensity units at the target CF and compression of the target, using compressive input/output functions derived from the nonsimultaneous masking study. However, the combinations of lower-frequency maskers showed much less excess masking than predicted by the model. This cannot easily be attributed to factors like off-frequency listening, combination tone perception, or between-masker suppression. It was better predicted, however, by assuming weighted intensity summation of masker excitations. The optimum weights for the lower-frequency maskers were smaller than one, consistent with partial masker compression as indicated by recent psychoacoustic data.

  17. Learning non-Gaussian Time Series using the Box-Cox Gaussian Process

    OpenAIRE

    Rios, Gonzalo; Tobar, Felipe

    2018-01-01

    Gaussian processes (GPs) are Bayesian nonparametric generative models that provide interpretability of hyperparameters, admit closed-form expressions for training and inference, and are able to accurately represent uncertainty. To model general non-Gaussian data with complex correlation structure, GPs can be paired with an expressive covariance kernel and then fed into a nonlinear transformation (or warping). However, overparametrising the kernel and the warping is known to, respectively, hin...

  18. Numerical modeling of macrodispersion in heterogeneous media: a comparison of multi-Gaussian and non-multi-Gaussian models

    Science.gov (United States)

    Wen, Xian-Huan; Gómez-Hernández, J. Jaime

    1998-03-01

    The macrodispersion of an inert solute in a 2-D heterogeneous porous media is estimated numerically in a series of fields of varying heterogeneity. Four different random function (RF) models are used to model log-transmissivity (ln T) spatial variability, and for each of these models, ln T variance is varied from 0.1 to 2.0. The four RF models share the same univariate Gaussian histogram and the same isotropic covariance, but differ from one another in terms of the spatial connectivity patterns at extreme transmissivity values. More specifically, model A is a multivariate Gaussian model for which, by definition, extreme values (both high and low) are spatially uncorrelated. The other three models are non-multi-Gaussian: model B with high connectivity of high extreme values, model C with high connectivity of low extreme values, and model D with high connectivities of both high and low extreme values. Residence time distributions (RTDs) and macrodispersivities (longitudinal and transverse) are computed on ln T fields corresponding to the different RF models, for two different flow directions and at several scales. They are compared with each other, as well as with predicted values based on first-order analytical results. Numerically derived RTDs and macrodispersivities for the multi-Gaussian model are in good agreement with analytically derived values using first-order theories for log-transmissivity variance up to 2.0. The results from the non-multi-Gaussian models differ from each other and deviate largely from the multi-Gaussian results even when ln T variance is small. RTDs in non-multi-Gaussian realizations with high connectivity at high extreme values display earlier breakthrough than in multi-Gaussian realizations, whereas later breakthrough and longer tails are observed for RTDs from non-multi-Gaussian realizations with high connectivity at low extreme values. Longitudinal macrodispersivities in the non-multi-Gaussian realizations are, in general, larger than

  19. Non-Gaussian halo assembly bias

    International Nuclear Information System (INIS)

    Reid, Beth A.; Verde, Licia; Dolag, Klaus; Matarrese, Sabino; Moscardini, Lauro

    2010-01-01

    The strong dependence of the large-scale dark matter halo bias on the (local) non-Gaussianity parameter, f NL , offers a promising avenue towards constraining primordial non-Gaussianity with large-scale structure surveys. In this paper, we present the first detection of the dependence of the non-Gaussian halo bias on halo formation history using N-body simulations. We also present an analytic derivation of the expected signal based on the extended Press-Schechter formalism. In excellent agreement with our analytic prediction, we find that the halo formation history-dependent contribution to the non-Gaussian halo bias (which we call non-Gaussian halo assembly bias) can be factorized in a form approximately independent of redshift and halo mass. The correction to the non-Gaussian halo bias due to the halo formation history can be as large as 100%, with a suppression of the signal for recently formed halos and enhancement for old halos. This could in principle be a problem for realistic galaxy surveys if observational selection effects were to pick galaxies occupying only recently formed halos. Current semi-analytic galaxy formation models, for example, imply an enhancement in the expected signal of ∼ 23% and ∼ 48% for galaxies at z = 1 selected by stellar mass and star formation rate, respectively

  20. Area of isodensity contours in Gaussian and non-Gaussian fields

    International Nuclear Information System (INIS)

    Ryden, B.S.

    1988-01-01

    The area of isodensity contours in a smoothed density field can be measured by the contour-crossing statistic N1, the number of times per unit length that a line drawn through the density field pierces an isodensity contour. The contour-crossing statistic distinguishes between Gaussian and non-Gaussian fields and provides a measure of the effective slope of the power spectrum. The statistic is easy to apply and can be used on pencil beams and slices as well as on a three-dimensional field. 10 references

  1. A Novel Approach to Speaker Weight Estimation Using a Fusion of the i-vector and NFA Frameworks

    DEFF Research Database (Denmark)

    Poorjam, Amir Hossein; Bahari, Mohamad Hasan; Van hamme, Hogo

    2017-01-01

    -negative Factor Analysis (NFA) framework which is based on a constrained factor analysis on GMM weight supervectors. Then, the available information in both Gaussian means and Gaussian weights is exploited through a feature-level fusion of the i-vectors and the NFA vectors. Finally, a least-squares support vector......This paper proposes a novel approach for automatic speaker weight estimation from spontaneous telephone speech signals. In this method, each utterance is modeled using the i-vector framework which is based on the factor analysis on Gaussian Mixture Model (GMM) mean supervectors, and the Non...... regression is employed to estimate the weight of speakers from the given utterances. The proposed approach is evaluated on spontaneous telephone speech signals of National Institute of Standards and Technology 2008 and 2010 Speaker Recognition Evaluation corpora. To investigate the effectiveness...

  2. Neighborhood Disadvantage, Neighborhood Safety and Cardiometabolic Risk Factors in African Americans: Biosocial Associations in the Jackson Heart Study

    Science.gov (United States)

    Clark, Cheryl R.; Ommerborn, Mark J.; Hickson, DeMarc A.; Grooms, Kya N.; Sims, Mario; Taylor, Herman A.; Albert, Michelle A.

    2013-01-01

    Objective We examined associations between neighborhood socioeconomic disadvantage, perceived neighborhood safety and cardiometabolic risk factors, adjusting for health behaviors and socioeconomic status (SES) among African Americans. Methods Study participants were non-diabetic African Americans (n = 3,909) in the baseline examination (2000–2004) of the Jackson Heart Study. We measured eight risk factors: the metabolic syndrome, its five components, insulin resistance and cardiovascular inflammation. We assessed neighborhood socioeconomic disadvantage with US Census 2000 data. We assessed perceived neighborhood safety, health behaviors and SES via survey. We used generalized estimating equations to estimate associations with a random intercept model for neighborhood effects. Results After adjustment for health behaviors and SES, neighborhood socioeconomic disadvantage was associated with the metabolic syndrome in women (PR 1.13, 95% CI 1.01, 1.27). Lack of perceived safety was associated with elevated glucose (OR 1.36, 95% CI 1.03, 1.80) and waist circumference (PR 1.06, 95% CI 1.02, 1.11) among women, and with elevated glucose (PR 1.30, 95% CI 1.02, 1.66) and insulin resistance (PR 1.25, 95% CI 1.08, 1.46) among men. Conclusions Neighborhood socioeconomic disadvantage and perceived safety should be considered as targets for intervention to reduce cardiometabolic risks among African Americans. PMID:23691005

  3. FEATURES BASED ON NEIGHBORHOOD PIXELS DENSITY - A STUDY AND COMPARISON

    Directory of Open Access Journals (Sweden)

    Satish Kumar

    2016-02-01

    Full Text Available In optical character recognition applications, the feature extraction method(s used to recognize document images play an important role. The features are the properties of the pattern that can be statistical, structural and/or transforms or series expansion. The structural features are difficult to compute particularly from hand-printed images. The structure of the strokes present inside the hand-printed images can be estimated using statistical means. In this paper three features have been purposed, those are based on the distribution of B/W pixels on the neighborhood of a pixel in an image. We name these features as Spiral Neighbor Density, Layer Pixel Density and Ray Density. The recognition performance of these features has been compared with two more features Neighborhood Pixels Weight and Total Distances in Four Directions already studied in our work. We have used more than 20000 Devanagari handwritten character images for conducting experiments. The experiments are conducted with two classifiers i.e. PNN and k-NN.

  4. H0 from cosmic chronometers and Type Ia supernovae, with Gaussian Processes and the novel Weighted Polynomial Regression method

    Science.gov (United States)

    Gómez-Valent, Adrià; Amendola, Luca

    2018-04-01

    In this paper we present new constraints on the Hubble parameter H0 using: (i) the available data on H(z) obtained from cosmic chronometers (CCH); (ii) the Hubble rate data points extracted from the supernovae of Type Ia (SnIa) of the Pantheon compilation and the Hubble Space Telescope (HST) CANDELS and CLASH Multy-Cycle Treasury (MCT) programs; and (iii) the local HST measurement of H0 provided by Riess et al. (2018), H0HST=(73.45±1.66) km/s/Mpc. Various determinations of H0 using the Gaussian processes (GPs) method and the most updated list of CCH data have been recently provided by Yu, Ratra & Wang (2018). Using the Gaussian kernel they find H0=(67.42± 4.75) km/s/Mpc. Here we extend their analysis to also include the most released and complete set of SnIa data, which allows us to reduce the uncertainty by a factor ~ 3 with respect to the result found by only considering the CCH information. We obtain H0=(67.06± 1.68) km/s/Mpc, which favors again the lower range of values for H0 and is in tension with H0HST. The tension reaches the 2.71σ level. We round off the GPs determination too by taking also into account the error propagation of the kernel hyperparameters when the CCH with and without H0HST are used in the analysis. In addition, we present a novel method to reconstruct functions from data, which consists in a weighted sum of polynomial regressions (WPR). We apply it from a cosmographic perspective to reconstruct H(z) and estimate H0 from CCH and SnIa measurements. The result obtained with this method, H0=(68.90± 1.96) km/s/Mpc, is fully compatible with the GPs ones. Finally, a more conservative GPs+WPR value is also provided, H0=(68.45± 2.00) km/s/Mpc, which is still almost 2σ away from H0HST.

  5. Response moments of dynamic systems under non-Gaussian random excitation by the equivalent non-Gaussian excitation method

    International Nuclear Information System (INIS)

    Tsuchida, Takahiro; Kimura, Koji

    2016-01-01

    Equivalent non-Gaussian excitation method is proposed to obtain the response moments up to the 4th order of dynamic systems under non-Gaussian random excitation. The non-Gaussian excitation is prescribed by the probability density and the power spectrum, and is described by an Ito stochastic differential equation. Generally, moment equations for the response, which are derived from the governing equations for the excitation and the system, are not closed due to the nonlinearity of the diffusion coefficient in the equation for the excitation even though the system is linear. In the equivalent non-Gaussian excitation method, the diffusion coefficient is replaced with the equivalent diffusion coefficient approximately to obtain a closed set of the moment equations. The square of the equivalent diffusion coefficient is expressed by a quadratic polynomial. In numerical examples, a linear system subjected to nonGaussian excitations with bimodal and Rayleigh distributions is analyzed by using the present method. The results show that the method yields the variance, skewness and kurtosis of the response with high accuracy for non-Gaussian excitation with the widely different probability densities and bandwidth. The statistical moments of the equivalent non-Gaussian excitation are also investigated to describe the feature of the method. (paper)

  6. Experiences of Intimate Partner and Neighborhood Violence and Their Association With Mental Health in Pregnant Women.

    Science.gov (United States)

    Barcelona de Mendoza, Veronica; Harville, Emily W; Savage, Jane; Giarratano, Gloria

    2018-03-01

    Both intimate partner violence and neighborhood crime have been associated with worse mental health outcomes, but less is known about cumulative effects. This association was studied in a sample of pregnant women who were enrolled in a study of disaster exposure, prenatal care, and mental and physical health outcomes between 2010 and 2012. Women were interviewed about their exposure to intimate partner violence and perceptions of neighborhood safety, crime, and disorder. Main study outcomes included symptoms of poor mental health; including depression, pregnancy-specific anxiety (PA), and posttraumatic stress disorder (PTSD). Logistic regression was used to examine predictors of mental health with adjustment for confounders. Women who experienced high levels of intimate partner violence and perceived neighborhood violence had increased odds of probable depression in individual models. Weighted high cumulative (intimate partner and neighborhood) experiences of violence were also associated with increased odds of having probable depression when compared with those with low violence. Weighed high cumulative violence was also associated with increased odds of PTSD. This study provides additional evidence that cumulative exposure to violence is associated with poorer mental health in pregnant women.

  7. Neighborhood design for walking and biking: physical activity and body mass index.

    Science.gov (United States)

    Brown, Barbara B; Smith, Ken R; Hanson, Heidi; Fan, Jessie X; Kowaleski-Jones, Lori; Zick, Cathleen D

    2013-03-01

    Neighborhood designs often relate to physical activity and to BMI. Does neighborhood walkability/bikeability relate to BMI and obesity risk and does moderate-to-vigorous physical activity (MVPA) account for some of the relationship? Census 2000 provided walkability/bikeability measures-block group proportions of workers who walk or bike to work, housing age, and population density-and National Health and Nutrition Examination Study (NHANES 2003-2006) provided MVPA accelerometer measures. Regression analyses (2011-2012) adjusted for geographic clustering and multiple control variables. Greater density and older housing were associated with lower male BMI in bivariate analyses, but there were no density and housing age effects in multivariate models. For women, greater proportions of neighborhood workers who walk to work (M=0.02) and more MVPA was associated with lower BMI and lower obesity risk. For men, greater proportions of workers who bike to work (M=0.004) and more MVPA was associated with lower BMI and obesity risk. For both effects, MVPA partially mediated the relationships between walkability/bikeability and BMI. If such associations are causal, doubling walk and bike-to-work proportions (to 0.04 and 0.008) would have -0.3 and -0.33 effects on the average BMIs of adult women and men living in the neighborhood. This equates to 1.5 pounds for a 64-inch-tall woman and 2.3 pounds for a 69-inch-tall man. Although walking/biking to work is rare in the U.S., greater proportions of such workers in neighborhoods relate to lower weight and higher MVPA. Bikeability merits greater attention as a modifiable activity-friendliness factor, particularly for men. Copyright © 2013 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Neighborhood Poverty and Adolescent Development

    Science.gov (United States)

    McBride Murry, Velma; Berkel, Cady; Gaylord-Harden, Noni K.; Copeland-Linder, Nikeea; Nation, Maury

    2011-01-01

    This article provides a comprehensive review of studies conducted over the past decade on the effects of neighborhood and poverty on adolescent normative and nonnormative development. Our review includes a summary of studies examining the associations between neighborhood poverty and adolescent identity development followed by a review of studies…

  9. Analytic matrix elements with shifted correlated Gaussians

    DEFF Research Database (Denmark)

    Fedorov, D. V.

    2017-01-01

    Matrix elements between shifted correlated Gaussians of various potentials with several form-factors are calculated analytically. Analytic matrix elements are of importance for the correlated Gaussian method in quantum few-body physics.......Matrix elements between shifted correlated Gaussians of various potentials with several form-factors are calculated analytically. Analytic matrix elements are of importance for the correlated Gaussian method in quantum few-body physics....

  10. Gentrification and binge drinking in California neighborhoods: It matters how long you've lived there.

    Science.gov (United States)

    Izenberg, Jacob M; Mujahid, Mahasin S; Yen, Irene H

    2018-07-01

    Neighborhood context plays a role in binge drinking, a behavior with major health and economic costs. Gentrification, the influx of capital and residents of higher socioeconomic status into historically-disinvested neighborhoods, is a growing trend with the potential to place urban communities under social and financial pressure. Hypothesizing that these pressures and other community changes resulting from gentrification could be tied to excessive alcohol consumption, we examined the relationship between gentrification and binge drinking in California neighborhoods. California census tracts were categorized as non-gentrifiable, stable (gentrifiable), or gentrifying from 2006 to 2015. Outcomes and covariates were obtained from the California Health Interview Survey using combined 2013-2015 data (n = 60,196). Survey-weighted logistic regression tested for associations between gentrification and any binge drinking in the prior 12 months. Additional models tested interactions between gentrification and other variables of interest, including housing tenure, federal poverty level, race/ethnicity, sex, and duration of neighborhood residence. A third of respondents reported past-year binge drinking. Controlling for demographic covariates, gentrification was not associated with binge drinking in the population overall (AOR = 1.13, 95% CI = 0.95-1.34), but was associated with binge drinking among those living in the neighborhood gentrification is associated with binge drinking. Further understanding the relationship between gentrification and high-risk alcohol use is important for policy and public health interventions mitigating the impact of this process. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Semiparametric inference on the fractal index of Gaussian and conditionally Gaussian time series data

    DEFF Research Database (Denmark)

    Bennedsen, Mikkel

    Using theory on (conditionally) Gaussian processes with stationary increments developed in Barndorff-Nielsen et al. (2009, 2011), this paper presents a general semiparametric approach to conducting inference on the fractal index, α, of a time series. Our setup encompasses a large class of Gaussian...

  12. Strategies of Building a Stronger Sense of Community for Sustainable Neighborhoods: Comparing Neighborhood Accessibility with Community Empowerment Programs

    Directory of Open Access Journals (Sweden)

    Te-I Albert Tsai

    2014-05-01

    Full Text Available New Urbanist development in the U.S. aims at enhancing a sense of community and seeks to return to the design of early transitional neighborhoods which have pedestrian-oriented environments with retail shops and services within walking distances of housing. Meanwhile, 6000 of Taiwan’s community associations have been running community empowerment programs supported by the Council for Cultural Affairs that have helped many neighborhoods to rebuild so-called community cohesion. This research attempts to evaluate whether neighborhoods with facilities near housing and shorter travel distances within a neighborhood would promote stronger social interactions and form a better community attachment than neighborhoods that have various opportunities for residents to participate in either formal or informal social gatherings. After interviewing and surveying residents from 19 neighborhoods in Taipei’s Beitou District, and correlating the psychological sense of community with inner neighborhood’s daily travel distances and numbers of participatory activities held by community organizations under empowerment programs together with frequencies of regular individual visits and casual meetings, statistical evidence yielded that placing public facilities near residential locations is more effective than providing various programs for elevating a sense of community.

  13. Weighted finite impulse response filter for chromatic dispersion equalization in coherent optical fiber communication systems

    Science.gov (United States)

    Zeng, Ziyi; Yang, Aiying; Guo, Peng; Feng, Lihui

    2018-01-01

    Time-domain CD equalization using finite impulse response (FIR) filter is now a common approach for coherent optical fiber communication systems. The complex weights of FIR taps are calculated from a truncated impulse response of the CD transfer function, and the modulus of the complex weights is constant. In our work, we take the limited bandwidth of a single channel signal into account and propose weighted FIRs to improve the performance of CD equalization. The key in weighted FIR filters is the selection and optimization of weighted functions. In order to present the performance of different types of weighted FIR filters, a square-root raised cosine FIR (SRRC-FIR) and a Gaussian FIR (GS-FIR) are investigated. The optimization of square-root raised cosine FIR and Gaussian FIR are made in term of the bit rate error (BER) of QPSK and 16QAM coherent detection signal. The results demonstrate that the optimized parameters of the weighted filters are independent of the modulation format, symbol rate and the length of transmission fiber. With the optimized weighted FIRs, the BER of CD equalization signal is decreased significantly. Although this paper has investigated two types of weighted FIR filters, i.e. SRRC-FIR filter and GS-FIR filter, the principle of weighted FIR can also be extended to other symmetric functions super Gaussian function, hyperbolic secant function and etc.

  14. Temporal Effects of Child and Adolescent Exposure to Neighborhood Disadvantage on Black/White Disparities in Young Adult Obesity.

    Science.gov (United States)

    Kravitz-Wirtz, Nicole

    2016-05-01

    This study investigates the effects of duration and timing of exposure to neighborhood disadvantage from birth through age 17 years on obesity incidence in early adulthood and black/white disparities therein. Individual- and household-level data from the 1970-2011 waves of the Panel Study of Income Dynamics are merged with census data on respondents' neighborhoods (n = 1,498). Marginal structural models with inverse probability of treatment and censoring weights are used to quantify the probability of being obese at least once between ages 18 and 30 years as a function of cumulative exposure to neighborhood disadvantage throughout childhood and adolescence or during each of three developmental stages therein. Longer term exposure to neighborhood disadvantage from ages 0-17 years is more common among blacks than among whites and is associated with significantly greater odds of being obese at least once in early adulthood. Exposure to neighborhood-level deprivation during adolescence (ages 10-17 years) appears more consequential for future (young adult) obesity than exposure that occurs earlier in childhood. The duration and timing of exposure to neighborhood disadvantage during childhood and adolescence are associated with obesity incidence in early adulthood for both blacks and whites. However, given inequalities in the likelihood and persistence of experiencing neighborhood disadvantage as children and youth, such adverse effects are likely to be more concentrated among black versus white young adults. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  15. Equivalent non-Gaussian excitation method for response moment calculation of systems under non-Gaussian random excitation

    International Nuclear Information System (INIS)

    Tsuchida, Takahiro; Kimura, Koji

    2015-01-01

    Equivalent non-Gaussian excitation method is proposed to obtain the moments up to the fourth order of the response of systems under non-Gaussian random excitation. The excitation is prescribed by the probability density and power spectrum. Moment equations for the response can be derived from the stochastic differential equations for the excitation and the system. However, the moment equations are not closed due to the nonlinearity of the diffusion coefficient in the equation for the excitation. In the proposed method, the diffusion coefficient is replaced with the equivalent diffusion coefficient approximately to obtain a closed set of the moment equations. The square of the equivalent diffusion coefficient is expressed by the second-order polynomial. In order to demonstrate the validity of the method, a linear system to non-Gaussian excitation with generalized Gaussian distribution is analyzed. The results show the method is applicable to non-Gaussian excitation with the widely different kurtosis and bandwidth. (author)

  16. Entanglement in Gaussian matrix-product states

    International Nuclear Information System (INIS)

    Adesso, Gerardo; Ericsson, Marie

    2006-01-01

    Gaussian matrix-product states are obtained as the outputs of projection operations from an ancillary space of M infinitely entangled bonds connecting neighboring sites, applied at each of N sites of a harmonic chain. Replacing the projections by associated Gaussian states, the building blocks, we show that the entanglement range in translationally invariant Gaussian matrix-product states depends on how entangled the building blocks are. In particular, infinite entanglement in the building blocks produces fully symmetric Gaussian states with maximum entanglement range. From their peculiar properties of entanglement sharing, a basic difference with spin chains is revealed: Gaussian matrix-product states can possess unlimited, long-range entanglement even with minimum number of ancillary bonds (M=1). Finally we discuss how these states can be experimentally engineered from N copies of a three-mode building block and N two-mode finitely squeezed states

  17. Exploring associations between perceived home and work neighborhood environments, diet behaviors, and obesity: Results from a survey of employed adults in Missouri

    Directory of Open Access Journals (Sweden)

    Rachel Tabak, PhD, RD

    2016-12-01

    Full Text Available Dietary behaviors are associated with obesity, and may be influenced by the environment. The objective of the current work was to investigate whether perceptions of built environment factors related to eating in the residential neighborhood will have different, independent associations with BMI and dietary behaviors than perceived built environment factors in the worksite neighborhood. In 2012–2013, a cross-sectional telephone-survey of Missouri adults (n = 2015 assessed perceptions of home and workplace built environment factors related to eating, dietary behaviors, and height and weight. Logistic regression models explored associations between perceived neighborhood built environment variables, diet, and obesity. The only variable associated with any of the outcomes explored in the fully adjusted models was the home neighborhood composite scale. None of the work environment variables were significantly associated with any of the health/behavior outcomes after adjustment. Few associations were found after adjustment for personal and job-related characteristics, and none were identified with the workplace neighborhood environment. While few home environment associations were found after adjustment, and none were identified with the perceived workplace neighborhood environment, the current study adds to the limited literature looking at associations between the perceived neighborhood around the workplace neighborhood and the perceived neighborhood around the home and dietary behaviors and obesity in adults. Future studies are needed to determine whether relationships between these environments and behavior exist, and if so, if they are causal and warrant intervention attempts.

  18. Neighborhood crime and transit station access mode choice - phase III of neighborhood crime and travel behavior.

    Science.gov (United States)

    2015-08-01

    This report provides the findings from the third phase of a three-part study about the influences of neighborhood crimes on travel : mode choice. While previous phases found evidence that high levels of neighborhood crime discourage people from choos...

  19. A Network of Kalman Filters for MAI and ISI Compensation in a Non-Gaussian Environment

    Directory of Open Access Journals (Sweden)

    Sayadi Bessem

    2005-01-01

    Full Text Available This paper develops a new multiuser detector based on a network of kalman filters (NKF dealing with multiple access-interference (MAI, intersymbol Interference (ISI, and an impulsive observation noise. The two proposed schemes are based on the modeling of the DS-CDMA system by a discrete-time linear system that has non-Gaussian state and measurement noises. By approximating the non-Gaussian densities of the noises by a weighted sum of Gaussian terms and under the common MMSE estimation criterion, we first derive an NKF detector. This version is further optimized by introducing a feedback exploiting the ISI interference structure. The resulting scheme is an NKF detector based on a likelihood ratio test (LRT. Monte-Carlo simulations have shown that the NKF and the NKF based on LRT detectors significantly improve the efficiency and the performance of the classical Kalman algorithm.

  20. Neighborhood contextual factors, maternal smoking, and birth outcomes: multilevel analysis of the South Carolina PRAMS survey, 2000-2003.

    Science.gov (United States)

    Nkansah-Amankra, Stephen

    2010-08-01

    Previous studies investigating relationships among neighborhood contexts, maternal smoking behaviors, and birth outcomes (low birth weight [LBW] or preterm births) have produced mixed results. We evaluated independent effects of neighborhood contexts on maternal smoking behaviors and risks of LBW or preterm birth outcomes among mothers participating in the South Carolina Pregnancy Risk Assessment and Monitoring System (PRAMS) survey, 2000-2003. The PRAMS data were geocoded to 2000 U.S. Census data to create a multilevel data structure. We used a multilevel regression analysis (SAS PROC GLIMMIX) to estimate odds ratios (OR) and corresponding 95% confidence intervals (CI). In multivariable logistic regression models, high poverty, predominantly African American neighborhoods, upper quartiles of low education, and second quartile of neighborhood household crowding were significantly associated with LBW. However, only mothers resident in predominantly African American Census tract areas were statistically significantly at an increased risk of delivering preterm (OR 2.2, 95% CI 1.29-3.78). In addition, mothers resident in medium poverty neighborhoods remained modestly associated with smoking after adjustment for maternal-level covariates. The results also indicated that maternal smoking has more consistent effects on LBW than preterm births, particularly for mothers living in deprived neighborhoods. Interventions seeking to improve maternal and child health by reducing smoking during pregnancy need to engage specific community factors that encourage maternal quitting behaviors and reduce smoking relapse rates. Inclusion of maternal-level covariates in neighborhood models without careful consideration of the causal pathway might produce misleading interpretation of the results.

  1. Non-Gaussianity from isocurvature perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Masahiro; Nakayama, Kazunori; Sekiguchi, Toyokazu; Suyama, Teruaki [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Takahashi, Fuminobu, E-mail: kawasaki@icrr.u-tokyo.ac.jp, E-mail: nakayama@icrr.u-tokyo.ac.jp, E-mail: sekiguti@icrr.u-tokyo.ac.jp, E-mail: suyama@icrr.u-tokyo.ac.jp, E-mail: fuminobu.takahashi@ipmu.jp [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8568 (Japan)

    2008-11-15

    We develop a formalism for studying non-Gaussianity in both curvature and isocurvature perturbations. It is shown that non-Gaussianity in the isocurvature perturbation between dark matter and photons leaves distinct signatures in the cosmic microwave background temperature fluctuations, which may be confirmed in future experiments, or possibly even in the currently available observational data. As an explicit example, we consider the quantum chromodynamics axion and show that it can actually induce sizable non-Gaussianity for the inflationary scale, H{sub inf} = O(10{sup 9}-10{sup 11}) GeV.

  2. Handbook of Gaussian basis sets

    International Nuclear Information System (INIS)

    Poirier, R.; Kari, R.; Csizmadia, I.G.

    1985-01-01

    A collection of a large body of information is presented useful for chemists involved in molecular Gaussian computations. Every effort has been made by the authors to collect all available data for cartesian Gaussian as found in the literature up to July of 1984. The data in this text includes a large collection of polarization function exponents but in this case the collection is not complete. Exponents for Slater type orbitals (STO) were included for completeness. This text offers a collection of Gaussian exponents primarily without criticism. (Auth.)

  3. Defensible Spaces in Philadelphia: Exploring Neighborhood Boundaries Through Spatial Analysis

    Directory of Open Access Journals (Sweden)

    Rory Kramer

    2017-02-01

    Full Text Available Few spatial scales are as important to individual outcomes as the neighborhood. However, it is nearly impossible to define neighborhoods in a generalizable way. This article proposes that by shifting the focus to measuring neighborhood boundaries rather than neighborhoods, scholars can avoid the problem of the indefinable neighborhood and better approach questions of what predicts racial segregation across areas. By quantifying an externality space theory of neighborhood boundaries, this article introduces a novel form of spatial analysis to test where potential physical markers of neighborhood boundaries (major roads, rivers, railroads, and the like are associated with persistent racial boundaries between 1990 and 2010. Using Philadelphia as a case study, the paper identifies neighborhoods with persistent racial boundaries. It theorizes that local histories of white reactions to black in-migration explain which boundaries persistently resisted racial turnover, unlike the majority of Philadelphia’s neighborhoods, and that those racial boundaries shape the location, progress, and reaction to new residential development in those neighborhoods.

  4. Infrared maritime target detection using a probabilistic single Gaussian model of sea clutter in Fourier domain

    Science.gov (United States)

    Zhou, Anran; Xie, Weixin; Pei, Jihong; Chen, Yapei

    2018-02-01

    For ship targets detection in cluttered infrared image sequences, a robust detection method, based on the probabilistic single Gaussian model of sea background in Fourier domain, is put forward. The amplitude spectrum sequences at each frequency point of the pure seawater images in Fourier domain, being more stable than the gray value sequences of each background pixel in the spatial domain, are regarded as a Gaussian model. Next, a probability weighted matrix is built based on the stability of the pure seawater's total energy spectrum in the row direction, to make the Gaussian model more accurate. Then, the foreground frequency points are separated from the background frequency points by the model. Finally, the false-alarm points are removed utilizing ships' shape features. The performance of the proposed method is tested by visual and quantitative comparisons with others.

  5. Neighborhood Economic Enterprises: An Analysis, Survey, and Guide to Resources in Starting Up Neighborhood Enterprises.

    Science.gov (United States)

    Kotler, Neil G.

    This pamphlet provides information on the history of and current trends toward neighborhood economic enterprises and provides guidance for setting up such enterprises. A bibliography of books, articles, and newsletters that have information on how to start and sustain neighborhood businesses and cooperatives is provided. Also included is a list of…

  6. Neighborhood Disparities in the Restaurant Food Environment.

    Science.gov (United States)

    Martinez-Donate, Ana P; Espino, Jennifer Valdivia; Meinen, Amy; Escaron, Anne L; Roubal, Anne; Nieto, Javier; Malecki, Kristen

    2016-11-01

    Restaurant meals account for a significant portion of the American diet. Investigating disparities in the restaurant food environment can inform targeted interventions to increase opportunities for healthy eating among those who need them most. To examine neighborhood disparities in restaurant density and the nutrition environment within restaurants among a statewide sample of Wisconsin households. Households (N = 259) were selected from the 2009-2010 Survey of the Health of Wisconsin (SHOW), a population-based survey of Wisconsin adults. Restaurants in the household neighborhood were enumerated and audited using the Nutrition Environment Measures Survey for Restaurants (NEMS-R). Neighborhoods were defined as a 2- and 5-mile street-distance buffer around households in urban and non-urban areas, respectively. Adjusted linear regression models identified independent associations between sociodemographic household characteristics and neighborhood restaurant density and nutrition environment scores. On average, each neighborhood contained approximately 26 restaurants. On average, restaurants obtained 36.1% of the total nutrition environment points. After adjusting for household characteristics, higher restaurant density was associated with both younger and older household average age (P restaurant food environment in Wisconsin neighborhoods varies by age, race, and urbanicity, but offers ample room for improvement across socioeconomic groups and urbanicity levels. Future research must identify policy and environmental interventions to promote healthy eating in all restaurants, especially in young and/or rural neighborhoods in Wisconsin.

  7. Gaussian capacity of the quantum bosonic memory channel with additive correlated Gaussian noise

    International Nuclear Information System (INIS)

    Schaefer, Joachim; Karpov, Evgueni; Cerf, Nicolas J.

    2011-01-01

    We present an algorithm for calculation of the Gaussian classical capacity of a quantum bosonic memory channel with additive Gaussian noise. The algorithm, restricted to Gaussian input states, is applicable to all channels with noise correlations obeying certain conditions and works in the full input energy domain, beyond previous treatments of this problem. As an illustration, we study the optimal input states and capacity of a quantum memory channel with Gauss-Markov noise [J. Schaefer, Phys. Rev. A 80, 062313 (2009)]. We evaluate the enhancement of the transmission rate when using these optimal entangled input states by comparison with a product coherent-state encoding and find out that such a simple coherent-state encoding achieves not less than 90% of the capacity.

  8. Space, race, and poverty: Spatial inequalities in walkable neighborhood amenities?

    Directory of Open Access Journals (Sweden)

    John Whalen

    2012-05-01

    Full Text Available BACKGROUND Multiple and varied benefits have been suggested for increased neighborhood walkability. However, spatial inequalities in neighborhood walkability likely exist and may be attributable, in part, to residential segregation. OBJECTIVE Utilizing a spatial demographic perspective, we evaluated potential spatial inequalities in walkable neighborhood amenities across census tracts in Boston, MA (US. METHODS The independent variables included minority racial/ethnic population percentages and percent of families in poverty. Walkable neighborhood amenities were assessed with a composite measure. Spatial autocorrelation in key study variables were first calculated with the Global Moran's I statistic. Then, Spearman correlations between neighborhood socio-demographic characteristics and walkable neighborhood amenities were calculated as well as Spearman correlations accounting for spatial autocorrelation. We fit ordinary least squares (OLS regression and spatial autoregressive models when appropriate as a final step. RESULTS Significant positive spatial autocorrelation was found in neighborhood socio-demographic characteristics (e.g. census tract percent Black, but not walkable neighborhood amenities or in the OLS regression residuals. Spearman correlations between neighborhood socio-demographic characteristics and walkable neighborhood amenities were not statistically significant, nor were neighborhood socio-demographic characteristics significantly associated with walkable neighborhood amenities in OLS regression models. CONCLUSIONS Our results suggest that there is residential segregation in Boston and that spatial inequalities do not necessarily show up using a composite measure. COMMENTS Future research in other geographic areas (including international contexts and using different definitions of neighborhoods (including small-area definitions should evaluate if spatial inequalities are found using composite measures, but also should

  9. A review of neighborhood effects and early child development: How, where, and for whom, do neighborhoods matter?

    Science.gov (United States)

    Minh, Anita; Muhajarine, Nazeem; Janus, Magdalena; Brownell, Marni; Guhn, Martin

    2017-07-01

    This paper describes a scoping review of 42 studies of neighborhood effects on developmental health for children ages 0-6, published between 2009 and 2014. It focuses on three themes: (1) theoretical mechanisms that drive early childhood development, i.e. how neighborhoods matter for early childhood development; (2) dependence of such mechanisms on place-based characteristics i.e. where neighborhood effects occur; (3) dependence of such mechanisms on child characteristics, i.e. for whom is development most affected. Given that ecological systems theories postulate diverse mechanisms via which neighborhood characteristics affect early child development, we specifically examine evidence on mediation and/or moderation effects. We conclude by discussing future challenges, and proposing recommendations for analyses that utilize ecological longitudinal population-based databases. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Searching for non-Gaussianity in the WMAP data

    International Nuclear Information System (INIS)

    Bernui, A.; Reboucas, M. J.

    2009-01-01

    Some analyses of recent cosmic microwave background (CMB) data have provided hints that there are deviations from Gaussianity in the WMAP CMB temperature fluctuations. Given the far-reaching consequences of such a non-Gaussianity for our understanding of the physics of the early universe, it is important to employ alternative indicators in order to determine whether the reported non-Gaussianity is of cosmological origin, and/or extract further information that may be helpful for identifying its causes. We propose two new non-Gaussianity indicators, based on skewness and kurtosis of large-angle patches of CMB maps, which provide a measure of departure from Gaussianity on large angular scales. A distinctive feature of these indicators is that they provide sky maps of non-Gaussianity of the CMB temperature data, thus allowing a possible additional window into their origins. Using these indicators, we find no significant deviation from Gaussianity in the three and five-year WMAP Internal Linear Combination (ILC) map with KQ75 mask, while the ILC unmasked map exhibits deviation from Gaussianity, quantifying therefore the WMAP team recommendation to employ the new mask KQ75 for tests of Gaussianity. We also use our indicators to test for Gaussianity the single frequency foreground unremoved WMAP three and five-year maps, and show that the K and Ka maps exhibit a clear indication of deviation from Gaussianity even with the KQ75 mask. We show that our findings are robust with respect to the details of the method.

  11. Reproducing kernel Hilbert spaces of Gaussian priors

    NARCIS (Netherlands)

    Vaart, van der A.W.; Zanten, van J.H.; Clarke, B.; Ghosal, S.

    2008-01-01

    We review definitions and properties of reproducing kernel Hilbert spaces attached to Gaussian variables and processes, with a view to applications in nonparametric Bayesian statistics using Gaussian priors. The rate of contraction of posterior distributions based on Gaussian priors can be described

  12. Gaussian process regression analysis for functional data

    CERN Document Server

    Shi, Jian Qing

    2011-01-01

    Gaussian Process Regression Analysis for Functional Data presents nonparametric statistical methods for functional regression analysis, specifically the methods based on a Gaussian process prior in a functional space. The authors focus on problems involving functional response variables and mixed covariates of functional and scalar variables.Covering the basics of Gaussian process regression, the first several chapters discuss functional data analysis, theoretical aspects based on the asymptotic properties of Gaussian process regression models, and new methodological developments for high dime

  13. Ethnicity at the individual and neighborhood level as an explanation for moving out of the neighborhood

    NARCIS (Netherlands)

    Schaake, K.; Burgers, J.; Mulder, C.H.

    2010-01-01

    We address the influence of both the ethnic composition of the neighborhood and the ethnicity of individual residents on moving out of neighborhoods in the Netherlands. Using the Housing Research Netherlands survey and multinomial logistic regression analyses of moving out versus not moving or

  14. Rapid Development, Build-Out Ratio and Subsequent Neighborhood Turnover

    Directory of Open Access Journals (Sweden)

    George O. Rogers

    2018-04-01

    Full Text Available Neighborhood development is primarily comprised of structural elements that include design elements, nearby amenities and ecological attributes. This paper assumes that the process of development itself also influences the character of the neighborhood—specifically, that the rate of development and build-out ratio influences neighborhood turnover. While the structural components clearly set a framework for development, the process of development expresses the character of the neighborhood in subtle messages conveyed through the market. Neighborhoods in the rapidly growing university town of College Station, Texas are analyzed in terms of neighborhood design, nearby amenities and landscape ecology components. Residential property records are used to characterize each neighborhood in terms of the rate of development and current build-out ratio. The multivariate analysis indicates that the development rate increases subsequent neighborhood turnover rates while the build-out ratio decreases it.

  15. Comparison of Gaussian and non-Gaussian Atmospheric Profile Retrievals from Satellite Microwave Data

    Science.gov (United States)

    Kliewer, A.; Forsythe, J. M.; Fletcher, S. J.; Jones, A. S.

    2017-12-01

    The Cooperative Institute for Research in the Atmosphere at Colorado State University has recently developed two different versions of a mixed-distribution (lognormal combined with a Gaussian) based microwave temperature and mixing ratio retrieval system as well as the original Gaussian-based approach. These retrieval systems are based upon 1DVAR theory but have been adapted to use different descriptive statistics of the lognormal distribution to minimize the background errors. The input radiance data is from the AMSU-A and MHS instruments on the NOAA series of spacecraft. To help illustrate how the three retrievals are affected by the change in the distribution we are in the process of creating a new website to show the output from the different retrievals. Here we present initial results from different dynamical situations to show how the tool could be used by forecasters as well as for educators. However, as the new retrieved values are from a non-Gaussian based 1DVAR then they will display non-Gaussian behaviors that need to pass a quality control measure that is consistent with this distribution, and these new measures are presented here along with initial results for checking the retrievals.

  16. Neighborhood decline and the economic crisis : an introduction

    NARCIS (Netherlands)

    van Kempen, Ronald; Bolt, Gideon; van Ham, Maarten

    2016-01-01

    Urban neighborhoods are still important in the lives of its residents. Therefore, it is important to find out how the recent global financial and economic crisis affects these neighborhoods. Which types of neighborhoods and which residents suffer more than others? This introduction provides an

  17. Neighborhood food environments and Body Mass Index: the importance of in-store contents.

    Science.gov (United States)

    Rose, Donald; Hutchinson, Paul L; Bodor, J Nicholas; Swalm, Chris M; Farley, Thomas A; Cohen, Deborah A; Rice, Janet C

    2009-09-01

    Most public health studies on the neighborhood food environment have focused on types of stores and their geographic placement, yet marketing research has long documented the influence of in-store shelf-space on consumer behavior. This paper combines these two strands of research to test whether the aggregate availability of specific foods in a neighborhood is associated with the BMIs of its residents. Fielded from October 2004 to August 2005, this study combines mapping of retail food outlets, in-store surveys, and telephone interviews of residents from 103 randomly sampled urban census tracts in southeastern Louisiana. Linear shelf-space of fruits, vegetables, and energy-dense snack foods was measured in 307 food stores in the study tracts. Residential addresses, demographic information, and heights and weights were obtained from 1243 respondents through telephone interviews. Cumulative shelf-space of foods within defined distances of each respondent was calculated using observations from the in-store survey and probability-based assignments of shelf-space to all unobserved stores in the area. After controlling for sociodemographic variables, income, and car ownership, regression analysis, conducted in 2008, showed that cumulative shelf-space availability of energy-dense snack foods was positively, although modestly, associated with BMI. A 100-meter increase in shelf-space of these foods within 1 kilometer of a respondent's household was associated with an additional 0.1 BMI points. Fruit and vegetable shelf-space was not significantly related to BMI. Interventions that seek to improve the neighborhood food environment may need to focus on more than just increasing access to healthy foods, because the results suggest that the availability of energy-dense snack foods plays a role in weight status.

  18. Neighborhood Energy/Economic Development project

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    Energy costs impact low income communities more than anyone else. Low income residents pay a larger percentage of their incomes for energy costs. In addition, they generally have far less discretionary energy use to eliminate in response to increasing energy prices. Furthermore, with less discretionary income, home energy efficiency improvements are often too expensive. Small neighborhood businesses are in the same situation. Improved efficiency in the use of energy can improve this situation by reducing energy costs for residents and local businesses. More importantly, energy management programs can increase the demand for local goods and services and lead to the creation of new job training and employment opportunities. In this way, neighborhood based energy efficiency programs can support community economic development. The present project, undertaken with the support of the Urban Consortium Energy Task Force, was intended to serve as a demonstration of energy/economic programming at the neighborhood level. The San Francisco Neighborhood Energy/Economic Development (NEED) project was designed to be a visible demonstration of bringing the economic development benefits of energy management home to low-income community members who need it most. To begin, a Community Advisory Committee was established to guide the design of the programs to best meet needs of the community. Subsequently three neighborhood energy/economic development programs were developed: The small business energy assistance program; The youth training and weatherization program; and, The energy review of proposed housing development projects.

  19. Superdiffusion in a non-Markovian random walk model with a Gaussian memory profile

    Science.gov (United States)

    Borges, G. M.; Ferreira, A. S.; da Silva, M. A. A.; Cressoni, J. C.; Viswanathan, G. M.; Mariz, A. M.

    2012-09-01

    Most superdiffusive Non-Markovian random walk models assume that correlations are maintained at all time scales, e.g., fractional Brownian motion, Lévy walks, the Elephant walk and Alzheimer walk models. In the latter two models the random walker can always "remember" the initial times near t = 0. Assuming jump size distributions with finite variance, the question naturally arises: is superdiffusion possible if the walker is unable to recall the initial times? We give a conclusive answer to this general question, by studying a non-Markovian model in which the walker's memory of the past is weighted by a Gaussian centered at time t/2, at which time the walker had one half the present age, and with a standard deviation σt which grows linearly as the walker ages. For large widths we find that the model behaves similarly to the Elephant model, but for small widths this Gaussian memory profile model behaves like the Alzheimer walk model. We also report that the phenomenon of amnestically induced persistence, known to occur in the Alzheimer walk model, arises in the Gaussian memory profile model. We conclude that memory of the initial times is not a necessary condition for generating (log-periodic) superdiffusion. We show that the phenomenon of amnestically induced persistence extends to the case of a Gaussian memory profile.

  20. Neighborhood Effects on Health: Concentrated Advantage and Disadvantage

    Science.gov (United States)

    Finch, Brian K.; Do, D. Phuong; Heron, Melonie; Bird, Chloe; Seeman, Teresa; Lurie, Nicole

    2010-01-01

    We investigate an alternative conceptualization of neighborhood context and its association with health. Using an index that measures a continuum of concentrated advantage and disadvantage, we examine whether the relationship between neighborhood conditions and health varies by socio-economic status. Using NHANES III data geo-coded to census tracts, we find that while largely uneducated neighborhoods are universally deleterious, individuals with more education benefit from living in highly educated neighborhoods to a greater degree than individuals with lower levels of education. PMID:20627796

  1. Neighborhood Integration and Connectivity Predict Cognitive Performance and Decline

    Directory of Open Access Journals (Sweden)

    Amber Watts PhD

    2015-08-01

    Full Text Available Objective: Neighborhood characteristics may be important for promoting walking, but little research has focused on older adults, especially those with cognitive impairment. We evaluated the role of neighborhood characteristics on cognitive function and decline over a 2-year period adjusting for measures of walking. Method: In a study of 64 older adults with and without mild Alzheimer’s disease (AD, we evaluated neighborhood integration and connectivity using geographical information systems data and space syntax analysis. In multiple regression analyses, we used these characteristics to predict 2-year declines in factor analytically derived cognitive scores (attention, verbal memory, mental status adjusting for age, sex, education, and self-reported walking. Results : Neighborhood integration and connectivity predicted cognitive performance at baseline, and changes in cognitive performance over 2 years. The relationships between neighborhood characteristics and cognitive performance were not fully explained by self-reported walking. Discussion : Clearer definitions of specific neighborhood characteristics associated with walkability are needed to better understand the mechanisms by which neighborhoods may impact cognitive outcomes. These results have implications for measuring neighborhood characteristics, design and maintenance of living spaces, and interventions to increase walking among older adults. We offer suggestions for future research measuring neighborhood characteristics and cognitive function.

  2. Girls' self-efficacy in the context of neighborhood gender stratification.

    Science.gov (United States)

    Soller, Brian; Jackson, Aubrey L

    2018-05-01

    Scholars have linked neighborhood characteristics to self-efficacy, but few have considered how gender factors into this association. We integrate literature on neighborhoods, gender stratification, and self-efficacy to examine the association between women's relative resources among neighborhood residents and adolescents' self-efficacy. We hypothesize that girls report more self-efficacy when they reside in neighborhoods where women have more socioeconomic resources relative to men. We test this hypothesis using data from the Project on Human Development in Chicago Neighborhoods and the 1990 Census. Results from multilevel regression models with gender-interacted effects indicate the neighborhood level of women's relative resources was not associated with boys' self-efficacy. However, girls reported higher self-efficacy when women's relative resources in their neighborhoods were greater. This association persisted after including potential individual- and neighborhood-level confounding variables. Our study underscores the importance of attending to gendered processes when understanding how neighborhoods impact youth. Copyright © 2018. Published by Elsevier Inc.

  3. Gaussian operations and privacy

    International Nuclear Information System (INIS)

    Navascues, Miguel; Acin, Antonio

    2005-01-01

    We consider the possibilities offered by Gaussian states and operations for two honest parties, Alice and Bob, to obtain privacy against a third eavesdropping party, Eve. We first extend the security analysis of the protocol proposed in [Navascues et al. Phys. Rev. Lett. 94, 010502 (2005)]. Then, we prove that a generalized version of this protocol does not allow one to distill a secret key out of bound entangled Gaussian states

  4. Perceived and Police-Reported Neighborhood Crime: Linkages to Adolescent Activity Behaviors and Weight Status.

    Science.gov (United States)

    Forsyth, Ann; Wall, Melanie; Choo, Tse; Larson, Nicole; Van Riper, David; Neumark-Sztainer, Dianne

    2015-08-01

    Inadequate physical activity and obesity during adolescence are areas of public health concern. Questions exist about the role of neighborhoods in the etiology of these problems. This research addressed the relationships of perceived and objective reports of neighborhood crime to adolescent physical activity, screen media use, and body mass index (BMI). Socioeconomically and racially/ethnically diverse adolescents (N = 2,455, 53.4% female) from 20 urban, public middle and high schools in Minneapolis/St. Paul, Minnesota responded to a classroom survey in the Eating and Activity in Teens 2010 study. BMI was measured by research staff. Participants' mean age was 14.6 (standard deviation = 2.0); 82.7% represented racial/ethnic groups other than non-Hispanic white. Linear regressions examined associations between crime perceived by adolescents and crime reported to police and the outcomes of interest (BMI z-scores, physical activity, and screen time). Models were stratified by gender and adjusted for age, race/ethnicity, socioeconomic status, and school. BMI was positively associated with perceived crime among girls and boys and with reported crime in girls. For girls, there was an association between higher perceived crime and increased screen time; for boys, between higher reported property crime and reduced physical activity. Perceived crime was associated with reported crime, both property and personal, in both genders. Few prior studies of adolescents have studied the association between both perceived and reported crime and BMI. Community-based programs for youth should consider addressing adolescents' safety concerns along with other perceived barriers to physical activity. Interventions targeting actual crime rates are also important. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  5. Examining public open spaces by neighborhood-level walkability and deprivation.

    Science.gov (United States)

    Badland, Hannah M; Keam, Rosanna; Witten, Karen; Kearns, Robin

    2010-11-01

    Public open spaces (POS) are recognized as important to promote physical activity engagement. However, it is unclear how POS attributes, such as activities available, environmental quality, amenities present, and safety, are associated with neighborhood-level walkability and deprivation. Twelve neighborhoods were selected within 1 constituent city of Auckland, New Zealand based on higher (n = 6) or lower (n = 6) walkability characteristics. Neighborhoods were dichotomized as more (n = 7) or less (n = 5) socioeconomically deprived. POS (n = 69) were identified within these neighborhoods and audited using the New Zealand-Public Open Space Tool. Unpaired 1-way analysis of variance tests were applied to compare differences in attributes and overall score of POS by neighborhood walkability and deprivation. POS located in more walkable neighborhoods have significantly higher overall scores when compared with less walkable neighborhoods. Deprivation comparisons identified POS located in less deprived communities have better quality environments, but fewer activities and safety features present when compared with more deprived neighborhoods. A positive relationship existed between presence of POS attributes and neighborhood walkability, but the relationship between POS and neighborhood-level deprivation was less clear. Variation in neighborhood POS quality alone is unlikely to explain poorer health outcomes for residents in more deprived areas.

  6. A Longitudinal Analysis of the Influence of the Neighborhood Environment on Recreational Walking within the Neighborhood: Results from RESIDE

    OpenAIRE

    Christian, Hayley; Knuiman, Matthew; Divitini, Mark; Foster, Sarah; Hooper, Paula; Boruff, Bryan; Bull, Fiona; Giles-Corti, Billie

    2017-01-01

    Background: There is limited longitudinal evidence confirming the role of neighborhood environment attributes in encouraging people to walk more or if active people simply choose to live in activity-friendly neighborhoods. Natural experiments of policy changes to create more walkable communities provide stronger evidence for a causal effect of neighborhood environments on residents’ walking. Objectives: We aimed to investigate longitudinal associations between objective and perceived neighbor...

  7. Kinect Posture Reconstruction Based on a Local Mixture of Gaussian Process Models.

    Science.gov (United States)

    Liu, Zhiguang; Zhou, Liuyang; Leung, Howard; Shum, Hubert P H

    2016-11-01

    Depth sensor based 3D human motion estimation hardware such as Kinect has made interactive applications more popular recently. However, it is still challenging to accurately recognize postures from a single depth camera due to the inherently noisy data derived from depth images and self-occluding action performed by the user. In this paper, we propose a new real-time probabilistic framework to enhance the accuracy of live captured postures that belong to one of the action classes in the database. We adopt the Gaussian Process model as a prior to leverage the position data obtained from Kinect and marker-based motion capture system. We also incorporate a temporal consistency term into the optimization framework to constrain the velocity variations between successive frames. To ensure that the reconstructed posture resembles the accurate parts of the observed posture, we embed a set of joint reliability measurements into the optimization framework. A major drawback of Gaussian Process is its cubic learning complexity when dealing with a large database due to the inverse of a covariance matrix. To solve the problem, we propose a new method based on a local mixture of Gaussian Processes, in which Gaussian Processes are defined in local regions of the state space. Due to the significantly decreased sample size in each local Gaussian Process, the learning time is greatly reduced. At the same time, the prediction speed is enhanced as the weighted mean prediction for a given sample is determined by the nearby local models only. Our system also allows incrementally updating a specific local Gaussian Process in real time, which enhances the likelihood of adapting to run-time postures that are different from those in the database. Experimental results demonstrate that our system can generate high quality postures even under severe self-occlusion situations, which is beneficial for real-time applications such as motion-based gaming and sport training.

  8. Neighborhood level risk factors for type 1 diabetes in youth: the SEARCH case-control study

    Directory of Open Access Journals (Sweden)

    Liese Angela D

    2012-01-01

    Full Text Available Abstract Background European ecologic studies suggest higher socioeconomic status is associated with higher incidence of type 1 diabetes. Using data from a case-control study of diabetes among racially/ethnically diverse youth in the United States (U.S., we aimed to evaluate the independent impact of neighborhood characteristics on type 1 diabetes risk. Data were available for 507 youth with type 1 diabetes and 208 healthy controls aged 10-22 years recruited in South Carolina and Colorado in 2003-2006. Home addresses were used to identify Census tracts of residence. Neighborhood-level variables were obtained from 2000 U.S. Census. Multivariate generalized linear mixed models were applied. Results Controlling for individual risk factors (age, gender, race/ethnicity, infant feeding, birth weight, maternal age, number of household residents, parental education, income, state, higher neighborhood household income (p = 0.005, proportion of population in managerial jobs (p = 0.02, with at least high school education (p = 0.005, working outside the county (p = 0.04 and vehicle ownership (p = 0.03 were each independently associated with increased odds of type 1 diabetes. Conversely, higher percent minority population (p = 0.0003, income from social security (p = 0.002, proportion of crowded households (0.0497 and poverty (p = 0.008 were associated with a decreased odds. Conclusions Our study suggests that neighborhood characteristics related to greater affluence, occupation, and education are associated with higher type 1 diabetes risk. Further research is needed to understand mechanisms underlying the influence of neighborhood context.

  9. Better Buildings Neighborhood Program Progress Stories

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-04-19

    n neighborhoods across the country, stories are emerging constantly of individuals, businesses, and organizations that are benefiting from energy efficiency. Included are the stories of real people making their homes, businesses, and communities better with the help of the Better Buildings Neighborhood Program.

  10. Neighborhood social capital and individual health.

    NARCIS (Netherlands)

    Mohnen, S.M.; Groenewegen, P.P.; Völker, B.; Flap, H.

    2011-01-01

    Neighborhood social capital is increasingly considered to be an important determinant of an individual's health. Using data from the Netherlands we investigate the influence of neighborhood social capital on an individual's self-reported health, while accounting for other conditions of health on

  11. New deconvolution method for microscopic images based on the continuous Gaussian radial basis function interpolation model.

    Science.gov (United States)

    Chen, Zhaoxue; Chen, Hao

    2014-01-01

    A deconvolution method based on the Gaussian radial basis function (GRBF) interpolation is proposed. Both the original image and Gaussian point spread function are expressed as the same continuous GRBF model, thus image degradation is simplified as convolution of two continuous Gaussian functions, and image deconvolution is converted to calculate the weighted coefficients of two-dimensional control points. Compared with Wiener filter and Lucy-Richardson algorithm, the GRBF method has an obvious advantage in the quality of restored images. In order to overcome such a defect of long-time computing, the method of graphic processing unit multithreading or increasing space interval of control points is adopted, respectively, to speed up the implementation of GRBF method. The experiments show that based on the continuous GRBF model, the image deconvolution can be efficiently implemented by the method, which also has a considerable reference value for the study of three-dimensional microscopic image deconvolution.

  12. Geometry of perturbed Gaussian states and quantum estimation

    International Nuclear Information System (INIS)

    Genoni, Marco G; Giorda, Paolo; Paris, Matteo G A

    2011-01-01

    We address the non-Gaussianity (nG) of states obtained by weakly perturbing a Gaussian state and investigate the relationships with quantum estimation. For classical perturbations, i.e. perturbations to eigenvalues, we found that the nG of the perturbed state may be written as the quantum Fisher information (QFI) distance minus a term depending on the infinitesimal energy change, i.e. it provides a lower bound to statistical distinguishability. Upon moving on isoenergetic surfaces in a neighbourhood of a Gaussian state, nG thus coincides with a proper distance in the Hilbert space and exactly quantifies the statistical distinguishability of the perturbations. On the other hand, for perturbations leaving the covariance matrix unperturbed, we show that nG provides an upper bound to the QFI. Our results show that the geometry of non-Gaussian states in the neighbourhood of a Gaussian state is definitely not trivial and cannot be subsumed by a differential structure. Nevertheless, the analysis of perturbations to a Gaussian state reveals that nG may be a resource for quantum estimation. The nG of specific families of perturbed Gaussian states is analysed in some detail with the aim of finding the maximally non-Gaussian state obtainable from a given Gaussian one. (fast track communication)

  13. Obesogenic and youth oriented restaurant marketing in public housing neighborhoods.

    Science.gov (United States)

    Lee, Rebecca E; Heinrich, Katie M; Reese-Smith, Jacqueline Y; Regan, Gail R; Adamus-Leach, Heather J

    2014-03-01

    To compare restaurant marketing by restaurant and neighborhood type. All restaurants (61=fast food, FF; 72=table service, TS) within an 800-meter radius of 13 public housing developments (HD) and 4 comparison neighborhoods were audited using the Restaurant Assessment Tool©2010. HD neighborhoods were lower income and higher minority than comparison neighborhoods with similar density and street connectivity. Restaurants in HD neighborhoods had fewer healthy entrées than comparison neighborhoods. FF restaurants had cheaper beverages and more children's meals, supersize drinks, free prize with purchase, super-size items, special characters, and more items geared to driving than TS restaurants. Residents of lower socioeconomic neighborhoods may be differentially exposed to unhealthy food options.

  14. A Pareto-Based Adaptive Variable Neighborhood Search for Biobjective Hybrid Flow Shop Scheduling Problem with Sequence-Dependent Setup Time

    Directory of Open Access Journals (Sweden)

    Huixin Tian

    2016-01-01

    Full Text Available Different from most researches focused on the single objective hybrid flowshop scheduling (HFS problem, this paper investigates a biobjective HFS problem with sequence dependent setup time. The two objectives are the minimization of total weighted tardiness and the total setup time. To efficiently solve this problem, a Pareto-based adaptive biobjective variable neighborhood search (PABOVNS is developed. In the proposed PABOVNS, a solution is denoted as a sequence of all jobs and a decoding procedure is presented to obtain the corresponding complete schedule. In addition, the proposed PABOVNS has three major features that can guarantee a good balance of exploration and exploitation. First, an adaptive selection strategy of neighborhoods is proposed to automatically select the most promising neighborhood instead of the sequential selection strategy of canonical VNS. Second, a two phase multiobjective local search based on neighborhood search and path relinking is designed for each selected neighborhood. Third, an external archive with diversity maintenance is adopted to store the nondominated solutions and at the same time provide initial solutions for the local search. Computational results based on randomly generated instances show that the PABOVNS is efficient and even superior to some other powerful multiobjective algorithms in the literature.

  15. Non-Gaussianity in island cosmology

    International Nuclear Information System (INIS)

    Piao Yunsong

    2009-01-01

    In this paper we fully calculate the non-Gaussianity of primordial curvature perturbation of the island universe by using the second order perturbation equation. We find that for the spectral index n s ≅0.96, which is favored by current observations, the non-Gaussianity level f NL seen in an island will generally lie between 30 and 60, which may be tested by the coming observations. In the landscape, the island universe is one of anthropically acceptable cosmological histories. Thus the results obtained in some sense mean the coming observations, especially the measurement of non-Gaussianity, will be significant to clarify how our position in the landscape is populated.

  16. Effects of semantic neighborhood density in abstract and concrete words.

    Science.gov (United States)

    Reilly, Megan; Desai, Rutvik H

    2017-12-01

    Concrete and abstract words are thought to differ along several psycholinguistic variables, such as frequency and emotional content. Here, we consider another variable, semantic neighborhood density, which has received much less attention, likely because semantic neighborhoods of abstract words are difficult to measure. Using a corpus-based method that creates representations of words that emphasize featural information, the current investigation explores the relationship between neighborhood density and concreteness in a large set of English nouns. Two important observations emerge. First, semantic neighborhood density is higher for concrete than for abstract words, even when other variables are accounted for, especially for smaller neighborhood sizes. Second, the effects of semantic neighborhood density on behavior are different for concrete and abstract words. Lexical decision reaction times are fastest for words with sparse neighborhoods; however, this effect is stronger for concrete words than for abstract words. These results suggest that semantic neighborhood density plays a role in the cognitive and psycholinguistic differences between concrete and abstract words, and should be taken into account in studies involving lexical semantics. Furthermore, the pattern of results with the current feature-based neighborhood measure is very different from that with associatively defined neighborhoods, suggesting that these two methods should be treated as separate measures rather than two interchangeable measures of semantic neighborhoods. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Neighborhood social capital and individual health

    NARCIS (Netherlands)

    Mohnen, S.M.; Groenewegen, P.P.; Völker, B.G.M.; Flap, H.D.

    2010-01-01

    Neighborhood social capital is increasingly considered to be an important determinant of an individual’s health. Using data from the Netherlands we investigate the influence of neighborhood social capital on an individual’s self-reported health, while accounting for other conditions of health on

  18. Monogamy inequality for distributed gaussian entanglement.

    Science.gov (United States)

    Hiroshima, Tohya; Adesso, Gerardo; Illuminati, Fabrizio

    2007-02-02

    We show that for all n-mode Gaussian states of continuous variable systems, the entanglement shared among n parties exhibits the fundamental monogamy property. The monogamy inequality is proven by introducing the Gaussian tangle, an entanglement monotone under Gaussian local operations and classical communication, which is defined in terms of the squared negativity in complete analogy with the case of n-qubit systems. Our results elucidate the structure of quantum correlations in many-body harmonic lattice systems.

  19. Network neighborhood analysis with the multi-node topological overlap measure.

    Science.gov (United States)

    Li, Ai; Horvath, Steve

    2007-01-15

    The goal of neighborhood analysis is to find a set of genes (the neighborhood) that is similar to an initial 'seed' set of genes. Neighborhood analysis methods for network data are important in systems biology. If individual network connections are susceptible to noise, it can be advantageous to define neighborhoods on the basis of a robust interconnectedness measure, e.g. the topological overlap measure. Since the use of multiple nodes in the seed set may lead to more informative neighborhoods, it can be advantageous to define multi-node similarity measures. The pairwise topological overlap measure is generalized to multiple network nodes and subsequently used in a recursive neighborhood construction method. A local permutation scheme is used to determine the neighborhood size. Using four network applications and a simulated example, we provide empirical evidence that the resulting neighborhoods are biologically meaningful, e.g. we use neighborhood analysis to identify brain cancer related genes. An executable Windows program and tutorial for multi-node topological overlap measure (MTOM) based analysis can be downloaded from the webpage (http://www.genetics.ucla.edu/labs/horvath/MTOM/).

  20. Non-Communicable Disease Mortality and Risk Factors in Formal and Informal Neighborhoods, Ouagadougou, Burkina Faso: Evidence from a Health and Demographic Surveillance System.

    Directory of Open Access Journals (Sweden)

    Clémentine Rossier

    Full Text Available The expected growth in NCDs in cities is one of the most important health challenges of the coming decades in Sub-Saharan countries. This paper aims to fill the gap in our understanding of socio-economic differentials in NCD mortality and risk in low and middle income neighborhoods in urban Africa. We use data collected in the Ouagadougou Health and Demographic Surveillance System. 409 deaths were recorded between 2009-2011 among 20,836 individuals aged 35 years and older; verbal autopsies and the InterVA program were used to determine the probable cause of death. A random survey asked in 2011 1,039 adults aged 35 and over about tobacco use, heavy alcohol consumption, lack of physical activity and measured their weight, height, and blood pressure. These data reveal a high level of premature mortality due to NCDs in all neighborhoods: NCD mortality increases substantially by age 50. NCD mortality is greater in formal neighborhoods, while adult communicable disease mortality remains high, especially in informal neighborhoods. There is a high prevalence of risk factors for NCDs in the studied neighborhoods, with over one-fourth of the adults being overweight and over one-fourth having hypertension. Better-off residents are more prone to physical inactivity and excessive weight, while vulnerable populations such as widows/divorced individuals and migrants suffer more from higher blood pressure. Females have a significantly lower risk of being smokers or heavy drinkers, while they are more likely to be physically inactive or overweight, especially when married. Muslim individuals are less likely to be smokers or heavy drinkers, but have a higher blood pressure. Everything else being constant, individuals living in formal neighborhoods are more often overweight. The data presented make clear the pressing need to develop effective programs to reduce NCD risk across all types of neighborhoods in African cities, and suggest several entry points for

  1. Soft Sensor Modeling Based on Multiple Gaussian Process Regression and Fuzzy C-mean Clustering

    Directory of Open Access Journals (Sweden)

    Xianglin ZHU

    2014-06-01

    Full Text Available In order to overcome the difficulties of online measurement of some crucial biochemical variables in fermentation processes, a new soft sensor modeling method is presented based on the Gaussian process regression and fuzzy C-mean clustering. With the consideration that the typical fermentation process can be distributed into 4 phases including lag phase, exponential growth phase, stable phase and dead phase, the training samples are classified into 4 subcategories by using fuzzy C- mean clustering algorithm. For each sub-category, the samples are trained using the Gaussian process regression and the corresponding soft-sensing sub-model is established respectively. For a new sample, the membership between this sample and sub-models are computed based on the Euclidean distance, and then the prediction output of soft sensor is obtained using the weighting sum. Taking the Lysine fermentation as example, the simulation and experiment are carried out and the corresponding results show that the presented method achieves better fitting and generalization ability than radial basis function neutral network and single Gaussian process regression model.

  2. A brain MRI bias field correction method created in the Gaussian multi-scale space

    Science.gov (United States)

    Chen, Mingsheng; Qin, Mingxin

    2017-07-01

    A pre-processing step is needed to correct for the bias field signal before submitting corrupted MR images to such image-processing algorithms. This study presents a new bias field correction method. The method creates a Gaussian multi-scale space by the convolution of the inhomogeneous MR image with a two-dimensional Gaussian function. In the multi-Gaussian space, the method retrieves the image details from the differentiation of the original image and convolution image. Then, it obtains an image whose inhomogeneity is eliminated by the weighted sum of image details in each layer in the space. Next, the bias field-corrected MR image is retrieved after the Υ correction, which enhances the contrast and brightness of the inhomogeneity-eliminated MR image. We have tested the approach on T1 MRI and T2 MRI with varying bias field levels and have achieved satisfactory results. Comparison experiments with popular software have demonstrated superior performance of the proposed method in terms of quantitative indices, especially an improvement in subsequent image segmentation.

  3. Using GPS Data to Study Neighborhood Walkability and Physical Activity.

    Science.gov (United States)

    Rundle, Andrew G; Sheehan, Daniel M; Quinn, James W; Bartley, Katherine; Eisenhower, Donna; Bader, Michael M D; Lovasi, Gina S; Neckerman, Kathryn M

    2016-03-01

    Urban form characteristics intended to support pedestrian activity, collectively referred to as neighborhood walkability, are thought to increase total physical activity. However, little is known about how neighborhood walkability influences utilization of neighborhood space by residents and their overall physical activity. Sociodemographic information and data on mobility and physical activity over 1-week periods measured by GPS loggers and accelerometers were collected from 803 residents of New York City between November 2010 and November 2011. Potentially accessible neighborhood areas were defined as land area within a 1-kilometer distance of the subject's home (radial buffer) and within a 1-kilometer journey on the street network from the home (network buffer). To define actual areas utilized by subjects, a minimum convex polygon was plotted around GPS waypoints falling within 1 kilometer of the home. A neighborhood walkability scale was calculated for each neighborhood area. Data were analyzed in 2014. Total residential neighborhood space utilized by subjects was significantly associated with street intersection density and was significantly negatively associated with residential density and subway stop density within 1 kilometer of the home. Walkability scale scores were significantly higher within utilized as compared with non-utilized neighborhood areas. Neighborhood walkability in the utilized neighborhood area was positively associated with total weekly physical activity (32% [95% CI=17%, 49%] more minutes of moderate-equivalent physical activity across the interquartile range of walkability). Neighborhood walkability is associated with neighborhood spaces utilized by residents and total weekly physical activity. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  4. Neighborhood quality and labor market outcomes

    DEFF Research Database (Denmark)

    Damm, Anna Piil

    2014-01-01

    of refugee men. Their labor market outcomes are also not affected by the overall employment rate and the overall average skill level in the neighborhood. However, an increase in the average skill level of non-Western immigrant men living in the neighborhood raises their employment probability, while...

  5. Non-Gaussianity from inflation: theory and observations

    Science.gov (United States)

    Bartolo, N.; Komatsu, E.; Matarrese, S.; Riotto, A.

    2004-11-01

    This is a review of models of inflation and of their predictions for the primordial non-Gaussianity in the density perturbations which are thought to be at the origin of structures in the Universe. Non-Gaussianity emerges as a key observable to discriminate among competing scenarios for the generation of cosmological perturbations and is one of the primary targets of present and future Cosmic Microwave Background satellite missions. We give a detailed presentation of the state-of-the-art of the subject of non-Gaussianity, both from the theoretical and the observational point of view, and provide all the tools necessary to compute at second order in perturbation theory the level of non-Gaussianity in any model of cosmological perturbations. We discuss the new wave of models of inflation, which are firmly rooted in modern particle physics theory and predict a significant amount of non-Gaussianity. The review is addressed to both astrophysicists and particle physicists and contains useful tables which summarize the theoretical and observational results regarding non-Gaussianity.

  6. [Nutritional status and body composition of poor children in the outlying neighborhoods of La Plata, Argentina].

    Science.gov (United States)

    Oyhenart, Evelia E; Torres, María F; Quintero, Fabián A; Luis, María A; Cesani, María F; Zucchi, Mariel; Orden, Alicia B

    2007-09-01

    To evaluate nutritional status and body composition as indicators of quality of life among poor children served by neighborhood soup kitchens in La Plata, Argentina. From April to November 2004, we conducted a cross-sectional study of 608 healthy children from 1-11 years of age who were being served by two neighborhood soup kitchens in the outlying areas of the city of La Plata. The sample was stratified by age and sex. Height-for-age, weight-for age, and weight-for-height, were measured, as well as BMI, muscle mass and adipose tissue. Z-scores were computed for the data. Odds ratios and the respective 95% confidence intervals were calculated. Prevalence of low weight-for-age was 9%; low weight-for-height, 3%; and low height-for-age, 15%. The prevalence of overweight and obesity were 12.5% and 7.1%, respectively. Among the study sample, 47.2% had low muscle mass and 20.4% had low adipose tissue. Among overweight and obese children, adipose tissue was 34.3% higher than that of the reference population, while muscle mass was 12.5% lower. Undernutrition and obesity are both found among the community of children studied. The high prevalence of delayed growth (i.e., low height-for-age), undernutrition (i.e., low weight-for-age), and the acute lack of muscle mass even among overweight and obese children, seem to be part of the consequences of an inevitable process that unfolds in the face of adverse living conditions.

  7. Non-gaussianity versus nonlinearity of cosmological perturbations.

    Science.gov (United States)

    Verde, L

    2001-06-01

    Following the discovery of the cosmic microwave background, the hot big-bang model has become the standard cosmological model. In this theory, small primordial fluctuations are subsequently amplified by gravity to form the large-scale structure seen today. Different theories for unified models of particle physics, lead to different predictions for the statistical properties of the primordial fluctuations, that can be divided in two classes: gaussian and non-gaussian. Convincing evidence against or for gaussian initial conditions would rule out many scenarios and point us toward a physical theory for the origin of structures. The statistical distribution of cosmological perturbations, as we observe them, can deviate from the gaussian distribution in several different ways. Even if perturbations start off gaussian, nonlinear gravitational evolution can introduce non-gaussian features. Additionally, our knowledge of the Universe comes principally from the study of luminous material such as galaxies, but galaxies might not be faithful tracers of the underlying mass distribution. The relationship between fluctuations in the mass and in the galaxies distribution (bias), is often assumed to be local, but could well be nonlinear. Moreover, galaxy catalogues use the redshift as third spatial coordinate: the resulting redshift-space map of the galaxy distribution is nonlinearly distorted by peculiar velocities. Nonlinear gravitational evolution, biasing, and redshift-space distortion introduce non-gaussianity, even in an initially gaussian fluctuation field. I investigate the statistical tools that allow us, in principle, to disentangle the above different effects, and the observational datasets we require to do so in practice.

  8. Galaxy bias and primordial non-Gaussianity

    Energy Technology Data Exchange (ETDEWEB)

    Assassi, Valentin; Baumann, Daniel [DAMTP, Cambridge University, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Schmidt, Fabian, E-mail: assassi@ias.edu, E-mail: D.D.Baumann@uva.nl, E-mail: fabians@MPA-Garching.MPG.DE [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85748 Garching (Germany)

    2015-12-01

    We present a systematic study of galaxy biasing in the presence of primordial non-Gaussianity. For a large class of non-Gaussian initial conditions, we define a general bias expansion and prove that it is closed under renormalization, thereby showing that the basis of operators in the expansion is complete. We then study the effects of primordial non-Gaussianity on the statistics of galaxies. We show that the equivalence principle enforces a relation between the scale-dependent bias in the galaxy power spectrum and that in the dipolar part of the bispectrum. This provides a powerful consistency check to confirm the primordial origin of any observed scale-dependent bias. Finally, we also discuss the imprints of anisotropic non-Gaussianity as motivated by recent studies of higher-spin fields during inflation.

  9. Optimal cloning of mixed Gaussian states

    International Nuclear Information System (INIS)

    Guta, Madalin; Matsumoto, Keiji

    2006-01-01

    We construct the optimal one to two cloning transformation for the family of displaced thermal equilibrium states of a harmonic oscillator, with a fixed and known temperature. The transformation is Gaussian and it is optimal with respect to the figure of merit based on the joint output state and norm distance. The proof of the result is based on the equivalence between the optimal cloning problem and that of optimal amplification of Gaussian states which is then reduced to an optimization problem for diagonal states of a quantum oscillator. A key concept in finding the optimum is that of stochastic ordering which plays a similar role in the purely classical problem of Gaussian cloning. The result is then extended to the case of n to m cloning of mixed Gaussian states

  10. Galaxy bias and primordial non-Gaussianity

    International Nuclear Information System (INIS)

    Assassi, Valentin; Baumann, Daniel; Schmidt, Fabian

    2015-01-01

    We present a systematic study of galaxy biasing in the presence of primordial non-Gaussianity. For a large class of non-Gaussian initial conditions, we define a general bias expansion and prove that it is closed under renormalization, thereby showing that the basis of operators in the expansion is complete. We then study the effects of primordial non-Gaussianity on the statistics of galaxies. We show that the equivalence principle enforces a relation between the scale-dependent bias in the galaxy power spectrum and that in the dipolar part of the bispectrum. This provides a powerful consistency check to confirm the primordial origin of any observed scale-dependent bias. Finally, we also discuss the imprints of anisotropic non-Gaussianity as motivated by recent studies of higher-spin fields during inflation

  11. NEIGHBORHOOD NORMS AND SUBSTANCE USE AMONG TEENS

    Science.gov (United States)

    Musick, Kelly; Seltzer, Judith A.; Schwartz, Christine R.

    2008-01-01

    This paper uses new data from the Los Angeles Family and Neighborhood Survey (L.A. FANS) to examine how neighborhood norms shape teenagers’ substance use. Specifically, it takes advantage of clustered data at the neighborhood level to relate adult neighbors’ attitudes and behavior with respect to smoking, drinking, and drugs, which we treat as norms, to teenagers’ own smoking, drinking, and drug use. We use hierarchical linear models to account for parents’ attitudes and behavior and other characteristics of individuals and families. We also investigate how the association between neighborhood norms and teen behavior depends on: (1) the strength of norms, as measured by consensus in neighbors’ attitudes and conformity in their behavior; (2) the willingness and ability of neighbors to enforce norms, for instance, by monitoring teens’ activities; and (3) the degree to which teens are exposed to their neighbors. We find little association between neighborhood norms and teen substance use, regardless of how we condition the relationship. We discuss possible theoretical and methodological explanations for this finding. PMID:18496598

  12. Neighborhood differences in social capital in Ghent (Belgium): a multilevel approach.

    Science.gov (United States)

    Neutens, Tijs; Vyncke, Veerle; De Winter, Dieter; Willems, Sara

    2013-11-13

    Little research has focused on the spatial distribution of social capital, despite social capital's rising popularity in health research and policy. This study examines the neighborhood differences in social capital and the determinants that explain these differences. Five components of neighborhood social capital are identified by means of factor and reliability analyses using data collected in the cross-sectional SWING study from 762 inhabitants in 42 neighbourhoods in the city of Ghent (Belgium). Neighborhood differences in social capital are explored using hierarchical linear models with cross-level interactions. Significant neighborhood differences are found for social cohesion, informal social control and social support, but not for social leverage and generalized trust. Our findings suggest that neighborhood social capital depends on both characteristics of individuals living in the neighborhood (attachment to neighborhood) and characteristics of the neighborhood itself (deprivation and residential turnover). Our analysis further shows that neighborhood deprivation reinforces the negative effect of declining neighborhood attachment on social cohesion and informal social control. This study foregrounds the importance of contextual effects in encouraging neighborhood social capital. Given the importance of neighborhood-level characteristics, it can be anticipated social capital promoting initiatives are likely to be more effective when tailored to specific areas. Second, our analyses show that not all forms of social capital are influenced by contextual factors to the same extent, implying that changes in neighborhood characteristics are conducive to, say, trust while leaving social support unaffected. Finally, our analysis has demonstrated that complex interrelationships between individual- and neighborhood-level variables exist, which are often overlooked in current work.

  13. Healthy neighborhoods: walkability and air pollution.

    Science.gov (United States)

    Marshall, Julian D; Brauer, Michael; Frank, Lawrence D

    2009-11-01

    The built environment may influence health in part through the promotion of physical activity and exposure to pollution. To date, no studies have explored interactions between neighborhood walkability and air pollution exposure. We estimated concentrations of nitric oxide (NO), a marker for direct vehicle emissions), and ozone (O(3)) and a neighborhood walkability score, for 49,702 (89% of total) postal codes in Vancouver, British Columbia, Canada. NO concentrations were estimated from a land-use regression model, O(3) was estimated from ambient monitoring data; walkability was calculated based on geographic attributes such as land-use mix, street connectivity, and residential density. All three attributes exhibit an urban-rural gradient, with high walkability and NO concentrations, and low O(3) concentrations, near the city center. Lower-income areas tend to have higher NO concentrations and walkability and lower O(3) concentrations. Higher-income areas tend to have lower pollution (NO and O(3)). "Sweet-spot" neighborhoods (low pollution, high walkability) are generally located near but not at the city center and are almost exclusively higher income. Increased concentration of activities in urban settings yields both health costs and benefits. Our research identifies neighborhoods that do especially well (and especially poorly) for walkability and air pollution exposure. Work is needed to ensure that the poor do not bear an undue burden of urban air pollution and that neighborhoods designed for walking, bicycling, or mass transit do not adversely affect resident's exposure to air pollution. Analyses presented here could be replicated in other cities and tracked over time to better understand interactions among neighborhood walkability, air pollution exposure, and income level.

  14. Cultural mechanisms and the persistence of neighborhood violence.

    Science.gov (United States)

    Kirk, David S; Papachristos, Andrew V

    2011-01-01

    Sociologists have given considerable attention to identifying the neighborhood-level social-interactional mechanisms that influence outcomes such as crime, educational attainment, and health. Yet, cultural mechanisms are often overlooked in quantitative studies of neighborhood effects. This paper adds a cultural dimension to neighborhood effects research by exploring the consequences of legal cynicism. Legal cynicism refers to a cultural frame in which people perceive the law as illegitimate, unresponsive, and ill equipped to ensure public safety. The authors find that legal cynicism explains why homicide persisted in certain Chicago neighborhoods during the 1990s despite declines in poverty and declines in violence city-wide.

  15. Self-Reported Physical Activity within and outside the Neighborhood: Criterion-Related Validity of the Neighborhood Physical Activity Questionnaire in German Older Adults

    Science.gov (United States)

    Bödeker, Malte; Bucksch, Jens; Wallmann-Sperlich, Birgit

    2018-01-01

    The Neighborhood Physical Activity Questionnaire allows to assess physical activity within and outside the neighborhood. Study objectives were to examine the criterion-related validity and health/functioning associations of Neighborhood Physical Activity Questionnaire-derived physical activity in German older adults. A total of 107 adults aged…

  16. Prediction of sound transmission loss through multilayered panels by using Gaussian distribution of directional incident energy

    Science.gov (United States)

    Kang; Ih; Kim; Kim

    2000-03-01

    In this study, a new prediction method is suggested for sound transmission loss (STL) of multilayered panels of infinite extent. Conventional methods such as random or field incidence approach often given significant discrepancies in predicting STL of multilayered panels when compared with the experiments. In this paper, appropriate directional distributions of incident energy to predict the STL of multilayered panels are proposed. In order to find a weighting function to represent the directional distribution of incident energy on the wall in a reverberation chamber, numerical simulations by using a ray-tracing technique are carried out. Simulation results reveal that the directional distribution can be approximately expressed by the Gaussian distribution function in terms of the angle of incidence. The Gaussian function is applied to predict the STL of various multilayered panel configurations as well as single panels. The compared results between the measurement and the prediction show good agreements, which validate the proposed Gaussian function approach.

  17. Spatial Modeling Of Infant Mortality Rate In South Central Timor Regency Using GWLR Method With Adaptive Bisquare Kernel And Gaussian Kernel

    Directory of Open Access Journals (Sweden)

    Teguh Prawono Sabat

    2017-08-01

    Full Text Available Geographically Weighted Logistic Regression (GWLR was regression model consider the spatial factor, which could be used to analyze the IMR. The number of Infant Mortality as big as 100 cases in 2015 or 12 per 1000 live birth in South Central Timor Regency. The aim of this study was to determine the best modeling of GWLR with fixed weighting function and Adaptive Gaussian Kernel in the case of infant mortality in South Central Timor District in 2015. The response variable (Y in this study was a case of infant mortality, while variable predictor was the percentage of neonatal first visit (KN1 (X1, the percentage of neonatal visit 3 times (Complete KN (X2, the percentage of pregnant get Fe tablet (X3, percentage of poor families pre prosperous (X4. This was a non-reactive study, which is a measurement which individuals surveyed did not realize that they are part of a study, with analysis unit in 32 sub-districts of South Central Timor Districts. Data analysis used open source program that was Excel, R program, Quantum GIS and GWR4. The best GWLR spatial modeling with Adaptive Gaussian Kernel weighting function, a global model parameters GWLR Adaptive Gaussian Kernel weighting function obtained by g (x = 0.941086 - 0,892506X4, GWLR local models with adaptive Kernel bisquare weighting function in the 13 Districts were obtained g(x = 0 − 0X4, factors that affect the cases of infant mortality in 13 sub-districts of South Central Timor Regency in 2015 was the percentage of poor families pre prosperous.

  18. Information geometry of Gaussian channels

    International Nuclear Information System (INIS)

    Monras, Alex; Illuminati, Fabrizio

    2010-01-01

    We define a local Riemannian metric tensor in the manifold of Gaussian channels and the distance that it induces. We adopt an information-geometric approach and define a metric derived from the Bures-Fisher metric for quantum states. The resulting metric inherits several desirable properties from the Bures-Fisher metric and is operationally motivated by distinguishability considerations: It serves as an upper bound to the attainable quantum Fisher information for the channel parameters using Gaussian states, under generic constraints on the physically available resources. Our approach naturally includes the use of entangled Gaussian probe states. We prove that the metric enjoys some desirable properties like stability and covariance. As a by-product, we also obtain some general results in Gaussian channel estimation that are the continuous-variable analogs of previously known results in finite dimensions. We prove that optimal probe states are always pure and bounded in the number of ancillary modes, even in the presence of constraints on the reduced state input in the channel. This has experimental and computational implications. It limits the complexity of optimal experimental setups for channel estimation and reduces the computational requirements for the evaluation of the metric: Indeed, we construct a converging algorithm for its computation. We provide explicit formulas for computing the multiparametric quantum Fisher information for dissipative channels probed with arbitrary Gaussian states and provide the optimal observables for the estimation of the channel parameters (e.g., bath couplings, squeezing, and temperature).

  19. Directional support value of Gaussian transformation for infrared small target detection.

    Science.gov (United States)

    Yang, Changcai; Ma, Jiayi; Qi, Shengxiang; Tian, Jinwen; Zheng, Sheng; Tian, Xin

    2015-03-20

    Robust small target detection is one of the key techniques in IR search and tracking systems for self-defense or attacks. In this paper we present a robust solution for small target detection in a single IR image. The key ideas of the proposed method are to use the directional support value of Gaussian transform (DSVoGT) to enhance the targets, and use the multiscale representation provided by DSVoGT to reduce the false alarm rate. The original image is decomposed into sub-bands in different orientations by convolving the image with the directional support value filters, which are deduced from the weighted mapped least-squares-support vector machines (LS-SVMs). Based on the sub-band images, a support value of Gaussian matrix is constructed, and the trace of this matrix is then defined as the target measure. The corresponding multiscale correlations of the target measures are computed for enhancing target signal while suppressing the background clutter. We demonstrate the advantages of the proposed method on real IR images and compare the results against those obtained from standard detection approaches, including the top-hat filter, max-mean filter, max-median filter, min-local-Laplacian of Gaussian (LoG) filter, as well as LS-SVM. The experimental results on various cluttered background images show that the proposed method outperforms other detectors.

  20. Laguerre Gaussian beam multiplexing through turbulence

    CSIR Research Space (South Africa)

    Trichili, A

    2014-08-17

    Full Text Available We analyze the effect of atmospheric turbulence on the propagation of multiplexed Laguerre Gaussian modes. We present a method to multiplex Laguerre Gaussian modes using digital holograms and decompose the resulting field after encountering a...

  1. Generalized Gaussian Error Calculus

    CERN Document Server

    Grabe, Michael

    2010-01-01

    For the first time in 200 years Generalized Gaussian Error Calculus addresses a rigorous, complete and self-consistent revision of the Gaussian error calculus. Since experimentalists realized that measurements in general are burdened by unknown systematic errors, the classical, widespread used evaluation procedures scrutinizing the consequences of random errors alone turned out to be obsolete. As a matter of course, the error calculus to-be, treating random and unknown systematic errors side by side, should ensure the consistency and traceability of physical units, physical constants and physical quantities at large. The generalized Gaussian error calculus considers unknown systematic errors to spawn biased estimators. Beyond, random errors are asked to conform to the idea of what the author calls well-defined measuring conditions. The approach features the properties of a building kit: any overall uncertainty turns out to be the sum of a contribution due to random errors, to be taken from a confidence inter...

  2. The global financial crisis and neighborhood decline

    NARCIS (Netherlands)

    Zwiers, Merle; Bolt, Gideon; Van Ham, Maarten; Van Kempen, Ronald

    2016-01-01

    Neighborhood decline is a complex and multidimensional process. National and regional variations in economic and political structures (including varieties in national welfare state arrangements), combined with differences in neighborhood history, development, and population composition, make it

  3. MCEM algorithm for the log-Gaussian Cox process

    OpenAIRE

    Delmas, Celine; Dubois-Peyrard, Nathalie; Sabbadin, Regis

    2014-01-01

    Log-Gaussian Cox processes are an important class of models for aggregated point patterns. They have been largely used in spatial epidemiology (Diggle et al., 2005), in agronomy (Bourgeois et al., 2012), in forestry (Moller et al.), in ecology (sightings of wild animals) or in environmental sciences (radioactivity counts). A log-Gaussian Cox process is a Poisson process with a stochastic intensity depending on a Gaussian random eld. We consider the case where this Gaussian random eld is ...

  4. Neighborhood Influences on Late Life Cognition in the ACTIVE Study

    Directory of Open Access Journals (Sweden)

    Shannon M. Sisco

    2012-01-01

    Full Text Available Low neighborhood-level socioeconomic status has been associated with poorer health, reduced physical activity, increased psychological stress, and less neighborhood-based social support. These outcomes are correlates of late life cognition, but few studies have specifically investigated the neighborhood as a unique source of explanatory variance in cognitive aging. This study supplemented baseline cognitive data from the ACTIVE (Advanced Cognitive Training for Independent and Vital Elderly study with neighborhood-level data to investigate (1 whether neighborhood socioeconomic position (SEP predicts cognitive level, and if so, whether it differentially predicts performance in general and specific domains of cognition and (2 whether neighborhood SEP predicts differences in response to short-term cognitive intervention for memory, reasoning, or processing speed. Neighborhood SEP positively predicted vocabulary, but did not predict other general or specific measures of cognitive level, and did not predict individual differences in response to cognitive intervention.

  5. Support for physical activity policies and perceptions of work and neighborhood environments: variance by BMI and activity status at the county and individual levels.

    Science.gov (United States)

    Gustat, Jeanette; O'Malley, Keelia; Hu, Tian; Tabak, Rachel G; Goins, Karin Valentine; Valko, Cheryl; Litt, Jill; Eyler, Amy

    2014-01-01

    To examine support for local policies encouraging physical activity and perceived neighborhood environment characteristics by physical activity and weight status of respondents across U.S. counties. We used a random-digit-dial, computer-assisted telephone interview (CATI) to conduct a cross-sectional telephone questionnaire in selected U.S. counties in 2011. Counties with high prevalences of obesity and sedentary behavior (HH; n = 884) and counties with low prevalences of obesity and sedentary behavior (LL; n = 171) were selected nationally. Adult respondents from HH (n = 642) and LL (n = 566) counties. Questions were asked of respondents, pertaining to support for physical activity policies in various settings, neighborhood features, time spent in physical activity and sedentary behaviors, self-reported weight and height, and personal demographic information. Means and frequencies were calculated; bivariable and multivariable linear and logistic regression models, developed. Models were adjusted for individual characteristics and county HH/LL status. Respondents in LL counties perceived their neighborhood and work environments to be more supportive of healthy behaviors and were more supportive of local physical activity policies than respondents in HH counties (p physical activity, and decreased sedentary behavior. Policy support and neighborhood environments are associated with behaviors. Results can inform targeting policy agendas to facilitate the improvement of environments (community, work, and school) to be more supportive of physical activity.

  6. Neighborhood Influences on Vehicle-Pedestrian Crash Severity.

    Science.gov (United States)

    Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas

    2017-12-01

    Socioeconomic factors are known to be contributing factors for vehicle-pedestrian crashes. Although several studies have examined the socioeconomic factors related to the location of the crashes, limited studies have considered the socioeconomic factors of the neighborhood where the road users live in vehicle-pedestrian crash modelling. This research aims to identify the socioeconomic factors related to both the neighborhoods where the road users live and where crashes occur that have an influence on vehicle-pedestrian crash severity. Data on vehicle-pedestrian crashes that occurred at mid-blocks in Melbourne, Australia, was analyzed. Neighborhood factors associated with road users' residents and location of crash were investigated using boosted regression tree (BRT). Furthermore, partial dependence plots were applied to illustrate the interactions between these factors. We found that socioeconomic factors accounted for 60% of the 20 top contributing factors to vehicle-pedestrian crashes. This research reveals that socioeconomic factors of the neighborhoods where the road users live and where the crashes occur are important in determining the severity of the crashes, with the former having a greater influence. Hence, road safety countermeasures, especially those focussing on the road users, should be targeted at these high-risk neighborhoods.

  7. Neighborhood Mapping Tool

    Data.gov (United States)

    Department of Housing and Urban Development — This tool assists the public and Choice Neighborhoods applicants to prepare data to submit with their grant application by allowing applicants to draw the exact...

  8. Linking network usage patterns to traffic Gaussianity fit

    NARCIS (Netherlands)

    de Oliveira Schmidt, R.; Sadre, R.; Melnikov, Nikolay; Schönwälder, Jürgen; Pras, Aiko

    Gaussian traffic models are widely used in the domain of network traffic modeling. The central assumption is that traffic aggregates are Gaussian distributed. Due to its importance, the Gaussian character of network traffic has been extensively assessed by researchers in the past years. In 2001,

  9. Characterisation of random Gaussian and non-Gaussian stress processes in terms of extreme responses

    Directory of Open Access Journals (Sweden)

    Colin Bruno

    2015-01-01

    Full Text Available In the field of military land vehicles, random vibration processes generated by all-terrain wheeled vehicles in motion are not classical stochastic processes with a stationary and Gaussian nature. Non-stationarity of processes induced by the variability of the vehicle speed does not form a major difficulty because the designer can have good control over the vehicle speed by characterising the histogram of instantaneous speed of the vehicle during an operational situation. Beyond this non-stationarity problem, the hard point clearly lies in the fact that the random processes are not Gaussian and are generated mainly by the non-linear behaviour of the undercarriage and the strong occurrence of shocks generated by roughness of the terrain. This non-Gaussian nature is expressed particularly by very high flattening levels that can affect the design of structures under extreme stresses conventionally acquired by spectral approaches, inherent to Gaussian processes and based essentially on spectral moments of stress processes. Due to these technical considerations, techniques for characterisation of random excitation processes generated by this type of carrier need to be changed, by proposing innovative characterisation methods based on time domain approaches as described in the body of the text rather than spectral domain approaches.

  10. Neighborhood Risk, Parental Socialization Styles, and Adolescent Conduct Problems

    Directory of Open Access Journals (Sweden)

    Enrique Gracia

    2010-12-01

    Full Text Available This article aims to analyze the influence of parental socialization styles (authoritarian, authoritative, indulgent and neglectful, and perceived neighborhood risk on three indicators of conduct problems in adolescence (school misconduct, delinquency, and drug use. The sample consists of 1,017 adolescents, aged between 12 and 17. Results from four multivariate factorial designs yielded only main effects of parenting styles and neighborhood risk. Adolescents from authoritative and indulgent families showed lower conduct problems than those with authoritarian and neglectful parents. Also, higher levels of perceived neighborhood risk were significantly associated with more conduct problems. There were no significant interaction effects between parenting styles and perceived neighborhood risk, but results yielded a significant interaction effect between neighborhood risk and sex. Overall, results do not support the idea that parenting styles are more effective under certain neighborhood risk conditions, and suggest that neighbourhood risk influences adolescents’ psychosocial adjustment beyond the influence of parental socialization styles.

  11. Stochastic differential calculus for Gaussian and non-Gaussian noises: A critical review

    Science.gov (United States)

    Falsone, G.

    2018-03-01

    In this paper a review of the literature works devoted to the study of stochastic differential equations (SDEs) subjected to Gaussian and non-Gaussian white noises and to fractional Brownian noises is given. In these cases, particular attention must be paid in treating the SDEs because the classical rules of the differential calculus, as the Newton-Leibnitz one, cannot be applied or are applicable with many difficulties. Here all the principal approaches solving the SDEs are reported for any kind of noise, highlighting the negative and positive properties of each one and making the comparisons, where it is possible.

  12. Prenatal exposure to traffic pollution: associations with reduced fetal growth and rapid infant weight gain.

    Science.gov (United States)

    Fleisch, Abby F; Rifas-Shiman, Sheryl L; Koutrakis, Petros; Schwartz, Joel D; Kloog, Itai; Melly, Steven; Coull, Brent A; Zanobetti, Antonella; Gillman, Matthew W; Gold, Diane R; Oken, Emily

    2015-01-01

    Prenatal air pollution exposure inhibits fetal growth, but implications for postnatal growth are unknown. We assessed weights and lengths of US infants in the Project Viva cohort at birth and 6 months. We estimated 3rd-trimester residential air pollution exposures using spatiotemporal models. We estimated neighborhood traffic density and roadway proximity at birth address using geographic information systems. We performed linear and logistic regression adjusted for sociodemographic variables, fetal growth, and gestational age at birth. Mean birth weight-for-gestational age z-score (fetal growth) was 0.17 (standard deviation [SD] = 0.97; n = 2,114), 0- to 6-month weight-for-length gain was 0.23 z-units (SD = 1.11; n = 689), and 17% had weight-for-length ≥95th percentile at 6 months of age. Infants exposed to the highest (vs. lowest) quartile of neighborhood traffic density had lower fetal growth (-0.13 units [95% confidence interval (CI) = -0.25 to -0.01]), more rapid 0- to 6-month weight-for-length gain (0.25 units [95% CI = 0.01 to 0.49]), and higher odds of weight-for-length ≥95th percentile at 6 months (1.84 [95% CI = 1.11 to 3.05]). Neighborhood traffic density was additionally associated with an infant being in both the lowest quartile of fetal growth and the highest quartile of 0- to 6-month weight-for-length gain (Q4 vs. Q1, odds ratio = 3.01 [95% CI = 1.08 to 8.44]). Roadway proximity and 3rd-trimester black carbon exposure were similarly associated with growth outcomes. For 3rd-trimester particulate matter (PM2.5), effect estimates were in the same direction, but smaller and imprecise. Infants exposed to higher traffic-related pollution in early life may exhibit more rapid postnatal weight gain in addition to reduced fetal growth.

  13. Phonotactics, Neighborhood Activation, and Lexical Access for Spoken Words

    Science.gov (United States)

    Vitevitch, Michael S.; Luce, Paul A.; Pisoni, David B.; Auer, Edward T.

    2012-01-01

    Probabilistic phonotactics refers to the relative frequencies of segments and sequences of segments in spoken words. Neighborhood density refers to the number of words that are phonologically similar to a given word. Despite a positive correlation between phonotactic probability and neighborhood density, nonsense words with high probability segments and sequences are responded to more quickly than nonsense words with low probability segments and sequences, whereas real words occurring in dense similarity neighborhoods are responded to more slowly than real words occurring in sparse similarity neighborhoods. This contradiction may be resolved by hypothesizing that effects of probabilistic phonotactics have a sublexical focus and that effects of similarity neighborhood density have a lexical focus. The implications of this hypothesis for models of spoken word recognition are discussed. PMID:10433774

  14. Neighborhood environments and obesity among Afro-Caribbean, African American, and Non-Hispanic white adults in the United States: results from the National Survey of American Life.

    Science.gov (United States)

    Sullivan, Samaah M; Brashear, Meghan M; Broyles, Stephanie T; Rung, Ariane L

    2014-04-01

    To examine possible associations between perceived neighborhood environments and obesity among a U.S. nationally representative sample of Afro-Caribbean, African American, and Non-Hispanic white adults. Data was used from the 2001-2003 National Survey of American Life (NSAL). All measures including neighborhood characteristics, height, and weight were self-reported. Multivariate logistic regression was used to compute odds ratios (ORs) of obesity (body mass index (BMI) ≥ 30 kg/m(2)) based on perceived neighborhood physical and social characteristics. The odds of obesity were significantly lower for adults who reported involvement in clubs, associations, or help groups (odds ratio (OR): 0.62; 95% confidence interval (CI): 0.44, 0.85) and perceived that they had a park, playground, or open space in their neighborhood (odds ratio (OR): 0.68; 95% confidence interval (CI): 0.47, 0.98). These associations remained significant after adjusting for leisure-time physical activity. Race/ethnicity appeared to modify the association between involvement in clubs, associations, or help groups and obesity. Providing parks, playgrounds, or open space or increasing the perception of those amenities may assist in the prevention of obesity, especially in ethnically diverse neighborhoods in the United States. More research is needed to investigate how perceptions of the neighborhood environment influence obesity and whether perceptions of the neighborhood environment differ between individuals within the same neighborhoods. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Gaussian maximally multipartite-entangled states

    Science.gov (United States)

    Facchi, Paolo; Florio, Giuseppe; Lupo, Cosmo; Mancini, Stefano; Pascazio, Saverio

    2009-12-01

    We study maximally multipartite-entangled states in the context of Gaussian continuous variable quantum systems. By considering multimode Gaussian states with constrained energy, we show that perfect maximally multipartite-entangled states, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of these states and their frustration for n≤7 .

  16. Gaussian maximally multipartite-entangled states

    International Nuclear Information System (INIS)

    Facchi, Paolo; Florio, Giuseppe; Pascazio, Saverio; Lupo, Cosmo; Mancini, Stefano

    2009-01-01

    We study maximally multipartite-entangled states in the context of Gaussian continuous variable quantum systems. By considering multimode Gaussian states with constrained energy, we show that perfect maximally multipartite-entangled states, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of these states and their frustration for n≤7.

  17. Loop corrections to primordial non-Gaussianity

    Science.gov (United States)

    Boran, Sibel; Kahya, E. O.

    2018-02-01

    We discuss quantum gravitational loop effects to observable quantities such as curvature power spectrum and primordial non-Gaussianity of cosmic microwave background (CMB) radiation. We first review the previously shown case where one gets a time dependence for zeta-zeta correlator due to loop corrections. Then we investigate the effect of loop corrections to primordial non-Gaussianity of CMB. We conclude that, even with a single scalar inflaton, one might get a huge value for non-Gaussianity which would exceed the observed value by at least 30 orders of magnitude. Finally we discuss the consequences of this result for scalar driven inflationary models.

  18. Variational Gaussian approximation for Poisson data

    Science.gov (United States)

    Arridge, Simon R.; Ito, Kazufumi; Jin, Bangti; Zhang, Chen

    2018-02-01

    The Poisson model is frequently employed to describe count data, but in a Bayesian context it leads to an analytically intractable posterior probability distribution. In this work, we analyze a variational Gaussian approximation to the posterior distribution arising from the Poisson model with a Gaussian prior. This is achieved by seeking an optimal Gaussian distribution minimizing the Kullback-Leibler divergence from the posterior distribution to the approximation, or equivalently maximizing the lower bound for the model evidence. We derive an explicit expression for the lower bound, and show the existence and uniqueness of the optimal Gaussian approximation. The lower bound functional can be viewed as a variant of classical Tikhonov regularization that penalizes also the covariance. Then we develop an efficient alternating direction maximization algorithm for solving the optimization problem, and analyze its convergence. We discuss strategies for reducing the computational complexity via low rank structure of the forward operator and the sparsity of the covariance. Further, as an application of the lower bound, we discuss hierarchical Bayesian modeling for selecting the hyperparameter in the prior distribution, and propose a monotonically convergent algorithm for determining the hyperparameter. We present extensive numerical experiments to illustrate the Gaussian approximation and the algorithms.

  19. Phase space structure of generalized Gaussian cat states

    International Nuclear Information System (INIS)

    Nicacio, Fernando; Maia, Raphael N.P.; Toscano, Fabricio; Vallejos, Raul O.

    2010-01-01

    We analyze generalized Gaussian cat states obtained by superposing arbitrary Gaussian states. The structure of the interference term of the Wigner function is always hyperbolic, surviving the action of a thermal reservoir. We also consider certain superpositions of mixed Gaussian states. An application to semiclassical dynamics is discussed.

  20. Neighborhood Poverty and Nonmarital Fertility: Spatial and Temporal Dimensions

    Science.gov (United States)

    South, Scott J.; Crowder, Kyle

    2010-01-01

    Data from 4,855 respondents to the Panel Study of Income Dynamics were used to examine spatial and temporal dimensions of the effect of neighborhood poverty on teenage premarital childbearing. Although high poverty in the immediate neighborhood increased the risk of becoming an unmarried parent, high poverty in surrounding neighborhoods reduced…

  1. Prediction and retrodiction with continuously monitored Gaussian states

    DEFF Research Database (Denmark)

    Zhang, Jinglei; Mølmer, Klaus

    2017-01-01

    Gaussian states of quantum oscillators are fully characterized by the mean values and the covariance matrix of their quadrature observables. We consider the dynamics of a system of oscillators subject to interactions, damping, and continuous probing which maintain their Gaussian state property......(t)$ to Gaussian states implies that the matrix $E(t)$ is also fully characterized by a vector of mean values and a covariance matrix. We derive the dynamical equations for these quantities and we illustrate their use in the retrodiction of measurements on Gaussian systems....

  2. Banks and the Racial Patterning of Homicide: A Study of Chicago Neighborhoods

    Directory of Open Access Journals (Sweden)

    María B. Veléz

    2009-12-01

    Full Text Available While bank investment is a driving force behind neighborhood viability, few studies have directly examined the effects of bank loan practices on neighborhood crime rates. This paper proposes that variation in residential bank loans helps explain the higher rates of homicide in minority neighborhoods in Chicago compared to white neighborhoods. It finds that black and Latino neighborhoods would experience fewer homicides if more financial capital were infused into these neighborhoods. These findings suggest that neighborhoods are shaped profoundly by the decisions of external economic actors.

  3. Mapping neighborhood scale survey responses with uncertainty metrics

    Directory of Open Access Journals (Sweden)

    Charles Robert Ehlschlaeger

    2016-12-01

    Full Text Available This paper presents a methodology of mapping population-centric social, infrastructural, and environmental metrics at neighborhood scale. This methodology extends traditional survey analysis methods to create cartographic products useful in agent-based modeling and geographic information analysis. It utilizes and synthesizes survey microdata, sub-upazila attributes, land use information, and ground truth locations of attributes to create neighborhood scale multi-attribute maps. Monte Carlo methods are employed to combine any number of survey responses to stochastically weight survey cases and to simulate survey cases' locations in a study area. Through such Monte Carlo methods, known errors from each of the input sources can be retained. By keeping individual survey cases as the atomic unit of data representation, this methodology ensures that important covariates are retained and that ecological inference fallacy is eliminated. These techniques are demonstrated with a case study from the Chittagong Division in Bangladesh. The results provide a population-centric understanding of many social, infrastructural, and environmental metrics desired in humanitarian aid and disaster relief planning and operations wherever long term familiarity is lacking. Of critical importance is that the resulting products have easy to use explicit representation of the errors and uncertainties of each of the input sources via the automatically generated summary statistics created at the application's geographic scale.

  4. Self-rated health and perceived violence in the neighborhood is heterogeneous between young women and men.

    Science.gov (United States)

    Almeida Bentes, Aline; Comini César, Cibele; Coelho Xavier, César; Teixeira Caiaffa, Waleska; Proietti, Fernando Augusto

    2017-12-19

    Self-rated health (SRH) is the general perception of an individual's own health and a key indicator to measure health in population-based studies. Few studies have examined the association between perceived urban violence and SRH among young adults. There were an estimated 475,000 deaths in 2012 as a result of homicide on the world. Sixty percent of these deaths occurred among males aged 15-44 years, making homicide the third leading cause of death for this population group. This study aimed to determine and quantify the association between sex-specific perception of violence in the neighborhood and SRH among young adults. Participants included 955 young adults (18-29 years) residing in Belo Horizonte, Minas Gerais, Brazil between 2008 and 2009. Logistic regression analysis was used to estimate the strength of the associations. The perceived urban violence score was constructed from variables that assessed the respondents' insecurity and perception of fear and danger of suffering some form of violence in the neighborhood using exploratory factor analysis. 18,3% of respondents rated their health as fair/ poor/very poor. Among women, fair/ poor/very poor SRH was associated with age between 25 and 29 years, low socioeconomic status score, being dissatisfied with weight, not exercising regularly, not having a healthy diet, and having some chronic disease. Men who rated their health as fair/poor/very poor more frequently smoked, were dissatisfied with their weight, did not exercise regularly, consumed fewer fruits and vegetables, and had some chronic disease compared to men who rated their health as very good/good. In the final model, after adjusting for confounding variables, perceived violence in the neighborhood was associated with poor SRH in young women only (OR = 1.52; 95% CI: 1.04-2.21). The results indicate that public and health policies should implement interventions on the neighborhood physical and social environment to improve the perception of safety

  5. Community Gardening, Neighborhood Meetings, and Social Capital

    Science.gov (United States)

    Alaimo, Katherine; Reischl, Thomas M.; Allen, Julie Ober

    2010-01-01

    This study examined associations between participation in community gardening/beautification projects and neighborhood meetings with perceptions of social capital at both the individual and neighborhood levels. Data were analyzed from a cross-sectional stratified random telephone survey conducted in Flint, Michigan (N=1916). Hierarchical linear…

  6. Super-resolving random-Gaussian apodized photon sieve.

    Science.gov (United States)

    Sabatyan, Arash; Roshaninejad, Parisa

    2012-09-10

    A novel apodized photon sieve is presented in which random dense Gaussian distribution is implemented to modulate the pinhole density in each zone. The random distribution in dense Gaussian distribution causes intrazone discontinuities. Also, the dense Gaussian distribution generates a substantial number of pinholes in order to form a large degree of overlap between the holes in a few innermost zones of the photon sieve; thereby, clear zones are formed. The role of the discontinuities on the focusing properties of the photon sieve is examined as well. Analysis shows that secondary maxima have evidently been suppressed, transmission has increased enormously, and the central maxima width is approximately unchanged in comparison to the dense Gaussian distribution. Theoretical results have been completely verified by experiment.

  7. Walks on SPR neighborhoods.

    Science.gov (United States)

    Caceres, Alan Joseph J; Castillo, Juan; Lee, Jinnie; St John, Katherine

    2013-01-01

    A nearest-neighbor-interchange (NNI)-walk is a sequence of unrooted phylogenetic trees, T1, T2, . . . , T(k) where each consecutive pair of trees differs by a single NNI move. We give tight bounds on the length of the shortest NNI-walks that visit all trees in a subtree-prune-and-regraft (SPR) neighborhood of a given tree. For any unrooted, binary tree, T, on n leaves, the shortest walk takes Θ(n²) additional steps more than the number of trees in the SPR neighborhood. This answers Bryant’s Second Combinatorial Challenge from the Phylogenetics Challenges List, the Isaac Newton Institute, 2011, and the Penny Ante Problem List, 2009.

  8. Can neighborhoods explain racial/ethnic differences in adolescent inactivity?

    Science.gov (United States)

    Richmond, Tracy K; Field, Alison E; Rich, Michael

    2007-01-01

    To determine if neighborhoods and their attributes contribute to racial/ethnic disparities in adolescent inactivity. We undertook a cross-sectional analysis of the National Longitudinal Study of Adolescent Health (n = 17,007), a nationally representative school-based study in the United States. Stratifying by gender, we used multivariate linear regression and multi-level modeling to determine whether neighborhood of residence may partially explain racial/ethnic disparities in adolescent physical inactivity, defined as hours viewing television or videos/DVDs and/or playing computer/video games each week. Participants lived in largely segregated communities. Black and Hispanic adolescent girls reported higher levels of inactivity than White adolescent girls (21 vs. 15 vs. 13 hours/week, respectively, p violent crime in the neighborhood was associated with inactivity, despite the individual's perception of his/her neighborhood as safe not being predictive. Although inactivity varies by race/ethnicity and gender, only in Hispanic adolescent girls does neighborhood fully explain the differential use. Our findings suggest that approaches other than changing neighborhood characteristics are needed to eliminate racial/ethnic disparities in adolescent inactivity.

  9. Neighborhood social capital and crime victimization: comparison of spatial regression analysis and hierarchical regression analysis.

    Science.gov (United States)

    Takagi, Daisuke; Ikeda, Ken'ichi; Kawachi, Ichiro

    2012-11-01

    Crime is an important determinant of public health outcomes, including quality of life, mental well-being, and health behavior. A body of research has documented the association between community social capital and crime victimization. The association between social capital and crime victimization has been examined at multiple levels of spatial aggregation, ranging from entire countries, to states, metropolitan areas, counties, and neighborhoods. In multilevel analysis, the spatial boundaries at level 2 are most often drawn from administrative boundaries (e.g., Census tracts in the U.S.). One problem with adopting administrative definitions of neighborhoods is that it ignores spatial spillover. We conducted a study of social capital and crime victimization in one ward of Tokyo city, using a spatial Durbin model with an inverse-distance weighting matrix that assigned each respondent a unique level of "exposure" to social capital based on all other residents' perceptions. The study is based on a postal questionnaire sent to 20-69 years old residents of Arakawa Ward, Tokyo. The response rate was 43.7%. We examined the contextual influence of generalized trust, perceptions of reciprocity, two types of social network variables, as well as two principal components of social capital (constructed from the above four variables). Our outcome measure was self-reported crime victimization in the last five years. In the spatial Durbin model, we found that neighborhood generalized trust, reciprocity, supportive networks and two principal components of social capital were each inversely associated with crime victimization. By contrast, a multilevel regression performed with the same data (using administrative neighborhood boundaries) found generally null associations between neighborhood social capital and crime. Spatial regression methods may be more appropriate for investigating the contextual influence of social capital in homogeneous cultural settings such as Japan. Copyright

  10. Demarcation of local neighborhoods to study relations between contextual factors and health

    Directory of Open Access Journals (Sweden)

    Chor Dora

    2010-06-01

    Full Text Available Abstract Background Several studies have highlighted the importance of collective social factors for population health. One of the major challenges is an adequate definition of the spatial units of analysis which present properties potentially related to the target outcomes. Political and administrative divisions of urban areas are the most commonly used definition, although they suffer limitations in their ability to fully express the neighborhoods as social and spatial units. Objective This study presents a proposal for defining the boundaries of local neighborhoods in Rio de Janeiro city. Local neighborhoods are constructed by means of aggregation of contiguous census tracts which are homogeneous regarding socioeconomic indicators. Methodology Local neighborhoods were created using the SKATER method (TerraView software. Criteria used for socioeconomic homogeneity were based on four census tract indicators (income, education, persons per household, and percentage of population in the 0-4-year age bracket considering a minimum population of 5,000 people living in each local neighborhood. The process took into account the geographic boundaries between administrative neighborhoods (a political-administrative division larger than a local neighborhood, but smaller than a borough and natural geographic barriers. Results The original 8,145 census tracts were collapsed into 794 local neighborhoods, distributed along 158 administrative neighborhoods. Local neighborhoods contained a mean of 10 census tracts, and there were an average of five local neighborhoods per administrative neighborhood. The local neighborhood units demarcated in this study are less socioeconomically heterogeneous than the administrative neighborhoods and provide a means for decreasing the well-known statistical variability of indicators based on census tracts. The local neighborhoods were able to distinguish between different areas within administrative neighborhoods

  11. Demarcation of local neighborhoods to study relations between contextual factors and health.

    Science.gov (United States)

    Santos, Simone M; Chor, Dora; Werneck, Guilherme Loureiro

    2010-06-29

    Several studies have highlighted the importance of collective social factors for population health. One of the major challenges is an adequate definition of the spatial units of analysis which present properties potentially related to the target outcomes. Political and administrative divisions of urban areas are the most commonly used definition, although they suffer limitations in their ability to fully express the neighborhoods as social and spatial units. This study presents a proposal for defining the boundaries of local neighborhoods in Rio de Janeiro city. Local neighborhoods are constructed by means of aggregation of contiguous census tracts which are homogeneous regarding socioeconomic indicators. Local neighborhoods were created using the SKATER method (TerraView software). Criteria used for socioeconomic homogeneity were based on four census tract indicators (income, education, persons per household, and percentage of population in the 0-4-year age bracket) considering a minimum population of 5,000 people living in each local neighborhood. The process took into account the geographic boundaries between administrative neighborhoods (a political-administrative division larger than a local neighborhood, but smaller than a borough) and natural geographic barriers. The original 8,145 census tracts were collapsed into 794 local neighborhoods, distributed along 158 administrative neighborhoods. Local neighborhoods contained a mean of 10 census tracts, and there were an average of five local neighborhoods per administrative neighborhood.The local neighborhood units demarcated in this study are less socioeconomically heterogeneous than the administrative neighborhoods and provide a means for decreasing the well-known statistical variability of indicators based on census tracts. The local neighborhoods were able to distinguish between different areas within administrative neighborhoods, particularly in relation to squatter settlements. Although the literature on

  12. Neighborhood-level social processes and substantiated cases of child maltreatment.

    Science.gov (United States)

    Molnar, Beth E; Goerge, Robert M; Gilsanz, Paola; Hill, Andrea; Subramanian, S V; Holton, John K; Duncan, Dustin T; Beatriz, Elizabeth D; Beardslee, William R

    2016-01-01

    Child maltreatment is a preventable public health problem. Research has demonstrated that neighborhood structural factors (e.g. poverty, crime) can influence the proportion of a neighborhood's children who are victims of maltreatment. A newer strategy is the identification of potentially modifiable social processes at the neighborhood level that can also influence maltreatment. Toward this end, this study examines neighborhood-level data (maltreatment cases substantiated by Illinois' child protection agency, 1995-2005, social processes measured by the Project on Human Development in Chicago Neighborhoods, U.S. Census data, proportions of neighborhoods on public assistance, and crime data) that were linked across clusters of contiguous, relatively homogenous Chicago, IL census tracts with respect to racial/ethnic and socioeconomic composition. Our analysis-an ecological-level, repeated cross-sectional design utilizing random-intercept logit models-with a sensitivity analysis using spatial models to control for spatial autocorrelation-revealed consistent associations between neighborhood social processes and maltreatment. Neighborhoods higher in collective efficacy, intergenerational closure, and social networks, and lower in disorder had lower proportions of neglect, physical abuse, and sexual abuse substantiated cases, controlling for differences in structural factors. Higher collective efficacy and social network size also predicted a lower proportion of substance-exposed infants. This research indicates that strategies to mobilize neighborhood-level protective factors may decrease child maltreatment more effectively than individual and family-focused efforts alone. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Interference MAC: Impact of improper Gaussian signaling on the rate region Pareto boundary

    KAUST Repository

    Kariminezhad, Ali

    2017-11-02

    Meeting the challenges of 5G demands better exploitation of the available spectrum by allowing multiple parties to share resources. For instance, a secondary unlicensed system can share resources with the cellular uplink of a primary licensed system for an improved spectral efficiency. This induces interference which has to be taken into account when designing such a system. A simple yet robust strategy is treating interference as noise (TIN), which is widely adapted in practice. It is thus important to study the capabilities and limitations of TIN in such scenarios. In this paper, we study this scenario modelled as multiple access channel (MAC) interfered by a Point-to-Point (P2P) channel, where we focus on the characterization of the rate region. We use improper Gaussian signaling (instead of proper) at the transmitters to increase the design flexibility, which offers the freedom of optimizing the transmit signal pseudo-variance in addition to its variance. We formulate the weighted max-min problem as a semidefinite program, and use semidefinite relaxation (SDR) to obtain a near-optimal solution. Numerical optimizations show that, by improper Gaussian signaling the achievable rates can be improved upto three times when compared to proper Gaussian signaling.

  14. Spatial dimensions of the effect of neighborhood disadvantage on delinquency

    NARCIS (Netherlands)

    Vogel, M.S.; South, S.J.

    2016-01-01

    esearch examining the relationship between neighborhood socioeconomic disadvantage and adolescent offending typically examines only the influence of residential neighborhoods. This strategy may be problematic as 1) neighborhoods are rarely spatially independent of each other and 2) adolescents spend

  15. A Systematic Review of Neighborhood Disparities in Point-of-Sale Tobacco Marketing.

    Science.gov (United States)

    Lee, Joseph G L; Henriksen, Lisa; Rose, Shyanika W; Moreland-Russell, Sarah; Ribisl, Kurt M

    2015-09-01

    We systematically reviewed evidence of disparities in tobacco marketing at tobacco retailers by sociodemographic neighborhood characteristics. We identified 43 relevant articles from 893 results of a systematic search in 10 databases updated May 28, 2014. We found 148 associations of marketing (price, placement, promotion, or product availability) with a neighborhood demographic of interest (socioeconomic disadvantage, race, ethnicity, and urbanicity). Neighborhoods with lower income have more tobacco marketing. There is more menthol marketing targeting urban neighborhoods and neighborhoods with more Black residents. Smokeless tobacco products are targeted more toward rural neighborhoods and neighborhoods with more White residents. Differences in store type partially explain these disparities. There are more inducements to start and continue smoking in lower-income neighborhoods and in neighborhoods with more Black residents. Retailer marketing may contribute to disparities in tobacco use. Clinicians should be aware of the pervasiveness of these environmental cues.

  16. A Systematic Review of Neighborhood Disparities in Point-of-Sale Tobacco Marketing

    Science.gov (United States)

    Henriksen, Lisa; Rose, Shyanika W.; Moreland-Russell, Sarah; Ribisl, Kurt M.

    2015-01-01

    We systematically reviewed evidence of disparities in tobacco marketing at tobacco retailers by sociodemographic neighborhood characteristics. We identified 43 relevant articles from 893 results of a systematic search in 10 databases updated May 28, 2014. We found 148 associations of marketing (price, placement, promotion, or product availability) with a neighborhood demographic of interest (socioeconomic disadvantage, race, ethnicity, and urbanicity). Neighborhoods with lower income have more tobacco marketing. There is more menthol marketing targeting urban neighborhoods and neighborhoods with more Black residents. Smokeless tobacco products are targeted more toward rural neighborhoods and neighborhoods with more White residents. Differences in store type partially explain these disparities. There are more inducements to start and continue smoking in lower-income neighborhoods and in neighborhoods with more Black residents. Retailer marketing may contribute to disparities in tobacco use. Clinicians should be aware of the pervasiveness of these environmental cues. PMID:26180986

  17. A Suboptimal Scheme for Multi-User Scheduling in Gaussian Broadcast Channels

    KAUST Repository

    Zafar, Ammar; Alouini, Mohamed-Slim; Shaqfeh, Mohammad

    2014-01-01

    This work proposes a suboptimal multi-user scheduling scheme for Gaussian broadcast channels which improves upon the classical single user selection, while considerably reducing complexity as compared to the optimal superposition coding with successful interference cancellation. The proposed scheme combines the two users with the maximum weighted instantaneous rate using superposition coding. The instantaneous rate and power allocation are derived in closed-form, while the long term rate of each user is derived in integral form for all channel distributions. Numerical results are then provided to characterize the prospected gains of the proposed scheme.

  18. A Suboptimal Scheme for Multi-User Scheduling in Gaussian Broadcast Channels

    KAUST Repository

    Zafar, Ammar

    2014-05-28

    This work proposes a suboptimal multi-user scheduling scheme for Gaussian broadcast channels which improves upon the classical single user selection, while considerably reducing complexity as compared to the optimal superposition coding with successful interference cancellation. The proposed scheme combines the two users with the maximum weighted instantaneous rate using superposition coding. The instantaneous rate and power allocation are derived in closed-form, while the long term rate of each user is derived in integral form for all channel distributions. Numerical results are then provided to characterize the prospected gains of the proposed scheme.

  19. Some continual integrals from gaussian forms

    International Nuclear Information System (INIS)

    Mazmanishvili, A.S.

    1985-01-01

    The result summary of continual integration of gaussian functional type is given. The summary contains 124 continual integrals which are the mathematical expectation of the corresponding gaussian form by the continuum of random trajectories of four types: real-valued Ornstein-Uhlenbeck process, Wiener process, complex-valued Ornstein-Uhlenbeck process and the stochastic harmonic one. The summary includes both the known continual integrals and the unpublished before integrals. Mathematical results of the continual integration carried in the work may be applied in the problem of the theory of stochastic process, approaching to the finding of mean from gaussian forms by measures generated by the pointed stochastic processes

  20. Current inversion induced by colored non-Gaussian noise

    International Nuclear Information System (INIS)

    Bag, Bidhan Chandra; Hu, Chin-Kung

    2009-01-01

    We study a stochastic process driven by colored non-Gaussian noises. For the flashing ratchet model we find that there is a current inversion in the variation of the current with the half-cycle period which accounts for the potential on–off operation. The current inversion almost disappears if one switches from non-Gaussian (NG) to Gaussian (G) noise. We also find that at low value of the asymmetry parameter of the potential the mobility controlled current is more negative for NG noise as compared to G noise. But at large magnitude of the parameter the diffusion controlled positive current is higher for the former than for the latter. On increasing the noise correlation time (τ), keeping the noise strength fixed, the mean velocity of a particle first increases and then decreases after passing through a maximum if the noise is non-Gaussian. For Gaussian noise, the current monotonically decreases. The current increases with the noise parameter p, 0< p<5/3, which is 1 for Gaussian noise

  1. Passivity and practical work extraction using Gaussian operations

    International Nuclear Information System (INIS)

    Brown, Eric G; Huber, Marcus; Friis, Nicolai

    2016-01-01

    Quantum states that can yield work in a cyclical Hamiltonian process form one of the primary resources in the context of quantum thermodynamics. Conversely, states whose average energy cannot be lowered by unitary transformations are called passive. However, while work may be extracted from non-passive states using arbitrary unitaries, the latter may be hard to realize in practice. It is therefore pertinent to consider the passivity of states under restricted classes of operations that can be feasibly implemented. Here, we ask how restrictive the class of Gaussian unitaries is for the task of work extraction. We investigate the notion of Gaussian passivity, that is, we present necessary and sufficient criteria identifying all states whose energy cannot be lowered by Gaussian unitaries. For all other states we give a prescription for the Gaussian operations that extract the maximal amount of energy. Finally, we show that the gap between passivity and Gaussian passivity is maximal, i.e., Gaussian-passive states may still have a maximal amount of energy that is extractable by arbitrary unitaries, even under entropy constraints. (paper)

  2. Associations of supermarket characteristics with weight status and body fat: a multilevel analysis of individuals within supermarkets (RECORD study.

    Directory of Open Access Journals (Sweden)

    Basile Chaix

    Full Text Available Previous research on the influence of the food environment on weight status has often used impersonal measures of the food environment defined for residential neighborhoods, which ignore whether people actually use the food outlets near their residence. To assess whether supermarkets are relevant contexts for interventions, the present study explored between-residential neighborhood and between-supermarket variations in body mass index (BMI and waist circumference (WC, and investigated associations between brands and characteristics of supermarkets and BMI or WC, after adjustment for individual and residential neighborhood characteristics.Participants in the RECORD Cohort Study (Paris Region, France, 2007-2008 were surveyed on the supermarket (brand and exact location where they conducted their food shopping. Overall, 7 131 participants shopped in 1 097 different supermarkets. Cross-classified multilevel linear models were estimated for BMI and WC.Just 11.4% of participants shopped for food primarily within their residential neighborhood. After accounting for participants' residential neighborhood, people shopping in the same supermarket had a more comparable BMI and WC than participants shopping in different supermarkets. After adjustment for individual and residential neighborhood characteristics, participants shopping in specific supermarket brands, in hard discount supermarkets (especially if they had a low education, and in supermarkets whose catchment area comprised low educated residents had a higher BMI/WC.A public health strategy to reduce excess weight may be to intervene on specific supermarkets to change food purchasing behavior, as supermarkets are where dietary preferences are materialized into definite purchased foods.

  3. Associations of supermarket characteristics with weight status and body fat: a multilevel analysis of individuals within supermarkets (RECORD study).

    Science.gov (United States)

    Chaix, Basile; Bean, Kathy; Daniel, Mark; Zenk, Shannon N; Kestens, Yan; Charreire, Hélène; Leal, Cinira; Thomas, Frédérique; Karusisi, Noëlla; Weber, Christiane; Oppert, Jean-Michel; Simon, Chantal; Merlo, Juan; Pannier, Bruno

    2012-01-01

    Previous research on the influence of the food environment on weight status has often used impersonal measures of the food environment defined for residential neighborhoods, which ignore whether people actually use the food outlets near their residence. To assess whether supermarkets are relevant contexts for interventions, the present study explored between-residential neighborhood and between-supermarket variations in body mass index (BMI) and waist circumference (WC), and investigated associations between brands and characteristics of supermarkets and BMI or WC, after adjustment for individual and residential neighborhood characteristics. Participants in the RECORD Cohort Study (Paris Region, France, 2007-2008) were surveyed on the supermarket (brand and exact location) where they conducted their food shopping. Overall, 7 131 participants shopped in 1 097 different supermarkets. Cross-classified multilevel linear models were estimated for BMI and WC. Just 11.4% of participants shopped for food primarily within their residential neighborhood. After accounting for participants' residential neighborhood, people shopping in the same supermarket had a more comparable BMI and WC than participants shopping in different supermarkets. After adjustment for individual and residential neighborhood characteristics, participants shopping in specific supermarket brands, in hard discount supermarkets (especially if they had a low education), and in supermarkets whose catchment area comprised low educated residents had a higher BMI/WC. A public health strategy to reduce excess weight may be to intervene on specific supermarkets to change food purchasing behavior, as supermarkets are where dietary preferences are materialized into definite purchased foods.

  4. Weight, body composition and handgrip strength among pulmonary tuberculosis patients

    DEFF Research Database (Denmark)

    Praygod, George; Range, Nyagosya; Faurholt-Jepsen, Daniel

    2011-01-01

    This study aimed to estimate deficits in weight, arm fat area (AFA), arm muscle area (AMA) and handgrip strength among smear-positive pulmonary TB (PTB+) patients starting treatment. We conducted a cross-sectional study among PTB+ patients and age- and sex-matched neighborhood controls. HIV statu...

  5. Tachyon mediated non-Gaussianity

    International Nuclear Information System (INIS)

    Dutta, Bhaskar; Leblond, Louis; Kumar, Jason

    2008-01-01

    We describe a general scenario where primordial non-Gaussian curvature perturbations are generated in models with extra scalar fields. The extra scalars communicate to the inflaton sector mainly through the tachyonic (waterfall) field condensing at the end of hybrid inflation. These models can yield significant non-Gaussianity of the local shape, and both signs of the bispectrum can be obtained. These models have cosmic strings and a nearly flat power spectrum, which together have been recently shown to be a good fit to WMAP data. We illustrate with a model of inflation inspired from intersecting brane models.

  6. Gaussian model for emission rate measurement of heated plumes using hyperspectral data

    Science.gov (United States)

    Grauer, Samuel J.; Conrad, Bradley M.; Miguel, Rodrigo B.; Daun, Kyle J.

    2018-02-01

    This paper presents a novel model for measuring the emission rate of a heated gas plume using hyperspectral data from an FTIR imaging spectrometer. The radiative transfer equation (RTE) is used to relate the spectral intensity of a pixel to presumed Gaussian distributions of volume fraction and temperature within the plume, along a line-of-sight that corresponds to the pixel, whereas previous techniques exclusively presume uniform distributions for these parameters. Estimates of volume fraction and temperature are converted to a column density by integrating the local molecular density along each path. Image correlation velocimetry is then employed on raw spectral intensity images to estimate the volume-weighted normal velocity at each pixel. Finally, integrating the product of velocity and column density along a control surface yields an estimate of the instantaneous emission rate. For validation, emission rate estimates were derived from synthetic hyperspectral images of a heated methane plume, generated using data from a large-eddy simulation. Calculating the RTE with Gaussian distributions of volume fraction and temperature, instead of uniform distributions, improved the accuracy of column density measurement by 14%. Moreover, the mean methane emission rate measured using our approach was within 4% of the ground truth. These results support the use of Gaussian distributions of thermodynamic properties in calculation of the RTE for optical gas diagnostics.

  7. Large deviations for Gaussian processes in Hoelder norm

    International Nuclear Information System (INIS)

    Fatalov, V R

    2003-01-01

    Some results are proved on the exact asymptotic representation of large deviation probabilities for Gaussian processes in the Hoeder norm. The following classes of processes are considered: the Wiener process, the Brownian bridge, fractional Brownian motion, and stationary Gaussian processes with power-law covariance function. The investigation uses the method of double sums for Gaussian fields

  8. Research Progresses of Halo Streams in the Solar Neighborhood

    Science.gov (United States)

    Xi-long, Liang; Jing-kun, Zhao; Yu-qin, Chen; Gang, Zhao

    2018-01-01

    The stellar streams originated from the Galactic halo may be detected when they pass by the solar neighborhood, and they still keep some information at their birth times. Thus, the investigation of halo streams in the solar neighborhood is very important for understanding the formation and evolution of our Galaxy. In this paper, the researches of halo streams in the solar neighborhood are briefly reviewed. We have introduced the methods how to detect the halo streams and identify their member stars, summarized the progresses in the observation of member stars of halo streams and in the study of their origins, introduced in detail how to analyze the origins of halo streams in the solar neighborhood by means of numerical simulation and chemical abundance, and finally discussed the prospects of the LAMOST and GAIA in the research of halo streams in the solar neighborhood.

  9. Effect of housing relocation and neighborhood environment on adolescent mental and behavioral health.

    Science.gov (United States)

    Byck, Gayle R; Bolland, John; Dick, Danielle; Swann, Gregory; Henry, David; Mustanski, Brian

    2015-11-01

    This study examined whether relocating from a high-poverty neighborhood to a lower poverty neighborhood as part of a federal housing relocation program (HOPE VI; Housing Opportunities for People Everywhere) had effects on adolescent mental and behavioral health compared to adolescents consistently living in lower poverty neighborhoods. Sociodemographic, risk behavior, and neighborhood data were collected from 592 low-income, primarily African-American adolescents and their primary caregivers. Structured psychiatric interviews were conducted with adolescents. Prerelocation neighborhood, demographic, and risk behavior data were also included. Hierarchical Linear Modeling (HLM) was used to test associations between neighborhood variables and risk outcomes. HLM was used to test whether the effect of neighborhood relocation and neighborhood characteristics might explain differences in sexual risk taking, substance use, and mental health outcomes. Adolescents who relocated of HOPE VI neighborhoods (n = 158) fared worse than control group participants (n = 429) on most self-reported mental health outcomes. The addition of subjective neighborhood measures generally did not substantively change these results. Our findings suggest that moving from a high-poverty neighborhood to a somewhat lower poverty neighborhood is not associated with better mental health and risk behavior outcomes in adolescents. The continued effects of having grown up in a high-poverty neighborhood, the small improvements in their new neighborhoods, the comparatively short length of time they lived in their new neighborhood, and/or the stress of moving appears to worsen most of the mental health outcomes of HOPE VI compared to control group participants who consistently lived in the lower poverty neighborhoods. © 2015 Association for Child and Adolescent Mental Health.

  10. Increasing Entanglement between Gaussian States by Coherent Photon Subtraction

    DEFF Research Database (Denmark)

    Ourjoumtsev, Alexei; Dantan, Aurelien Romain; Tualle Brouri, Rosa

    2007-01-01

    We experimentally demonstrate that the entanglement between Gaussian entangled states can be increased by non-Gaussian operations. Coherent subtraction of single photons from Gaussian quadrature-entangled light pulses, created by a nondegenerate parametric amplifier, produces delocalized states...

  11. Race, Neighborhood Economic Status, Income Inequality and Mortality.

    Directory of Open Access Journals (Sweden)

    Nicolle A Mode

    Full Text Available Mortality rates in the United States vary based on race, individual economic status and neighborhood. Correlations among these variables in most urban areas have limited what conclusions can be drawn from existing research. Our study employs a unique factorial design of race, sex, age and individual poverty status, measuring time to death as an objective measure of health, and including both neighborhood economic status and income inequality for a sample of middle-aged urban-dwelling adults (N = 3675. At enrollment, African American and White participants lived in 46 unique census tracts in Baltimore, Maryland, which varied in neighborhood economic status and degree of income inequality. A Cox regression model for 9-year mortality identified a three-way interaction among sex, race and individual poverty status (p = 0.03, with African American men living below poverty having the highest mortality. Neighborhood economic status, whether measured by a composite index or simply median household income, was negatively associated with overall mortality (p<0.001. Neighborhood income inequality was associated with mortality through an interaction with individual poverty status (p = 0.04. While racial and economic disparities in mortality are well known, this study suggests that several social conditions associated with health may unequally affect African American men in poverty in the United States. Beyond these individual factors are the influences of neighborhood economic status and income inequality, which may be affected by a history of residential segregation. The significant association of neighborhood economic status and income inequality with mortality beyond the synergistic combination of sex, race and individual poverty status suggests the long-term importance of small area influence on overall mortality.

  12. Walking to Work: The Roles of Neighborhood Walkability and Socioeconomic Deprivation.

    Science.gov (United States)

    Kelly, Cheryl M; Lian, Min; Struthers, Jim; Kammrath, Anna

    2015-06-16

    There are few studies that aimed to find a relationship between transportation-related physical activity and neighborhood socioeconomic condition using a composite deprivation index. The purpose of this study is to assess the relationship of neighborhood walkability and socioeconomic deprivation with percentage of adults walking to work. A walkability index and a socioeconomic deprivation index were created at block group-level. The outcome variable, percentage of adults who walk to work was dichotomized as walkability and socioeconomic deprivation with walking to work. Individuals in the most walkable neighborhoods are almost 5 times more likely to walk to work than individuals in the least walkable neighborhoods (OR = 4.90, 95% CI = 2.80-8.59). After adjusting for neighborhood socioeconomic deprivation, individuals in the most walkable neighborhoods are almost 3 times more likely to walk to work than individuals in the least walkable neighborhoods (OR = 2.98, 95% CI = 1.62-5.49). Walkability (as measured by the walkability index) is a very strong indicator of walking to work even after controlling for neighborhood socioeconomic disadvantage.

  13. New gaussian points for the solution of first order ordinary ...

    African Journals Online (AJOL)

    Numerical experiments carried out using the new Gaussian points revealed there efficiency on stiff differential equations. The results also reveal that methods using the new Gaussian points are more accurate than those using the standard Gaussian points on non-stiff initial value problems. Keywords: Gaussian points ...

  14. Does Race Matter in Neighborhood Preferences? Results from a Video Experiment

    Science.gov (United States)

    Krysan, Maria; Couper, Mick P.; Farley, Reynolds; Forman, Tyrone

    2013-01-01

    Persistent racial residential segregation is often seen as the result of the preferences of whites and blacks: whites prefer to live with whites while blacks wish to live near many other blacks. The origin of these preferences and their social psychological underpinnings are hotly debated. Are neighborhood preferences colorblind or race-conscious? Does neighborhood racial composition have a net influence upon preferences or is race a proxy for social class? If preferences are race-conscious, is this more a matter of a desire to be in a neighborhood with one’s “own kind” or to avoid being in a neighborhood with another racial group? We tested the racial proxy hypothesis using an innovative experiment that isolated the net effects of race and social class and followed it with an analysis of the social psychological factors associated with residential preferences. Face-to-face surveys using computer assisted interviewing were conducted with random samples of Detroit and Chicago residents. Respondents were asked how desirable they would rate neighborhoods shown in videos in which racial composition and social class characteristics were manipulated and they also completed—via computer assisted self-interviews—questions tapping into perceptions of discrimination, racial and neighborhood stereotypes, and in-group identity. We find that net of social class, the race of a neighborhood's residents significantly influenced how it was rated. Whites said the all-white neighborhoods were most desirable. The independent effect of racial composition was smaller among blacks and blacks identified the racially mixed neighborhood as most desirable. Hypotheses about how racial group identity, stereotypes, and experiences of discrimination influenced the effect of race of residents upon neighborhood preferences were tested and show that for whites, those who hold negative stereotypes about African Americans and the neighborhoods where they live are significantly influenced by

  15. Neighborhood Factors and Dating Violence Among Youth: A Systematic Review.

    Science.gov (United States)

    Johnson, Renee M; Parker, Elizabeth M; Rinehart, Jenny; Nail, Jennifer; Rothman, Emily F

    2015-09-01

    The purpose of this review is to summarize the empirical research on neighborhood-level factors and dating violence among adolescents and emerging adults to guide future research and practice. In 2015, a total of 20 articles were identified through a search of the literature using PubMed. Eligible articles included those that (1) had been published in a peer-reviewed journal since 2005; (2) reported a measure of association between at least one neighborhood-level factor and dating violence; and (3) had a study population of youth aged dating violence and neighborhood factors, and measures of effect. Results were summarized into three categories based on the aspect of neighborhood that was the focus of the work: demographic and structural characteristics (n=11); neighborhood disorder (n=12); and social disorganization (n=8). There was some evidence to suggest that neighborhood disadvantage is associated with dating violence, but very little evidence to suggest that residence characteristics (e.g., racial heterogeneity) are associated with dating violence. Results do suggest that perceived neighborhood disorder is associated with physical dating violence perpetration, but do not suggest that it is associated with physical dating violence victimization. Social control and community connectedness are both associated with dating violence, but findings on collective efficacy are mixed. Existing research suggests that neighborhood factors may be associated with dating violence. However, there is a limited body of research on the neighborhood context of dating violence, and more rigorous research is needed. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  16. ADOLESCENTS’ EXPOSURE TO COMMUNITY VIOLENCE: ARE NEIGHBORHOOD YOUTH ORGANIZATIONS PROTECTIVE?

    Science.gov (United States)

    Gardner, Margo; Brooks-Gunn, Jeanne

    2011-01-01

    Using data from the Project on Human Development in Chicago Neighborhoods (PHDCN), we identified a significant inverse association between the variety of youth organizations available at the neighborhood level and adolescents’ exposure to community violence. We examined two non-competing explanations for this finding. First, at the individual level, we tested the hypothesis that access to a greater variety of neighborhood youth organizations predicts adolescents’ participation in organized community-based activities, which, in turn, protects against community violence exposure. Second, at the neighborhood level, we tested the hypothesis that lower violent crime rates explain the inverse relation between neighborhood youth organization variety and community violence exposure. Our findings supported the latter of these two mechanisms. PMID:21666761

  17. Differences by Sexual Orientation in Perceptions of Neighborhood Cohesion: Implications for Health.

    Science.gov (United States)

    Henning-Smith, Carrie; Gonzales, Gilbert

    2018-06-01

    A large body of research documents the relationship between health and place, including the positive association between neighborhood cohesion and health. However, very little research has examined neighborhood cohesion by sexual orientation. This paper addresses that gap by examining differences in perceived neighborhood cohesion by sexual orientation. We use data from the 2016 National Health Interview Survey (n = 28,164 respondents aged 18 years and older) to examine bivariate differences by sexual orientation in four measures of neighborhood cohesion. We then use ordered logistic regression models to assess the relationship between sexual orientation and a scaled measure of neighborhood cohesion, adjusting for socio-demographic characteristics, living arrangements, health status, region, and neighborhood tenure. We find that lesbian, gay, and bisexual (LGB) adults are less likely to say that they live in a close-knit neighborhood (54.6 vs. 65.6%, p < 0.001), they can count on their neighbors (74.7 vs. 83.1%, p < 0.001), they trust their neighbors (75.5 vs. 83.7%, p < 0.001), or people in their neighborhood help each other out (72.9 vs. 83.1%, p < 0.001), compared to heterosexual adults. Even after controlling for socio-demographic factors, neighborhood cohesion scores are lower for LGB adults compared to heterosexual adults (odds ratio of better perceived neighborhood cohesion for sexual minorities: 0.70, p < 0.001). Overall, LGB adults report worse neighborhood cohesion across multiple measures, even after adjusting for individual characteristics and neighborhood tenure. Because living in a cohesive neighborhood is associated with better health outcomes, future research, community-level initiatives, and public policy efforts should focus on creating welcoming neighborhood environments for sexual minorities.

  18. Gaussian entanglement distribution via satellite

    Science.gov (United States)

    Hosseinidehaj, Nedasadat; Malaney, Robert

    2015-02-01

    In this work we analyze three quantum communication schemes for the generation of Gaussian entanglement between two ground stations. Communication occurs via a satellite over two independent atmospheric fading channels dominated by turbulence-induced beam wander. In our first scheme, the engineering complexity remains largely on the ground transceivers, with the satellite acting simply as a reflector. Although the channel state information of the two atmospheric channels remains unknown in this scheme, the Gaussian entanglement generation between the ground stations can still be determined. On the ground, distillation and Gaussification procedures can be applied, leading to a refined Gaussian entanglement generation rate between the ground stations. We compare the rates produced by this first scheme with two competing schemes in which quantum complexity is added to the satellite, thereby illustrating the tradeoff between space-based engineering complexity and the rate of ground-station entanglement generation.

  19. Neighborhood and Friendship Composition in Adolescence

    OpenAIRE

    Edling, Christofer; Rydgren, Jens

    2010-01-01

    The social surroundings in which an individual grows up and spends his or her everyday life have an effect on his or her life chances. Much of the research into this phenomenon focuses on so-called neighborhood effects and has put particular emphasis on the negative effects of growing up in a poor neighborhood. Originating from the sociological study of inner-city problems in the United States, the research has recentl...

  20. Male perpetration of teen dating violence: associations with neighborhood violence involvement, gender attitudes, and perceived peer and neighborhood norms.

    Science.gov (United States)

    Reed, Elizabeth; Silverman, Jay G; Raj, Anita; Decker, Michele R; Miller, Elizabeth

    2011-04-01

    This study aims to examine the link between male perpetration of teen dating violence (TDV) and neighborhood violence, as well as associations with gender attitudes and perceived peer and neighborhood norms related to violence among a sample of urban adolescent boys. Participants of this cross-sectional study (N = 275) were between the ages of 14 and 20 years and recruited from urban community health centers. Crude and adjusted logistic and linear regression models were used to examine TDV perpetration in relation to (a) neighborhood violence involvement, (b) perceptions of peer violence, (c) perceptions of neighborhood violence, and (d) gender attitudes. Slightly more than one in four (28%) boys reported at least one form of TDV perpetration; among boys who have ever had sex, almost half (45%) reported at least one form of TDV perpetration. In logistic and linear regression models adjusted for demographics, boys who reported TDV perpetration were more likely to report involvement in neighborhood violence (odds ratio (OR) = 3.1; 95% confidence interval (CI) = 1.7-5.5), beliefs that their friends have perpetrated TDV (OR = 2.7; 95%CI = 1.4-5.1), perceptions of violent activity within their neighborhood (OR = 3.0; 95%CI = 1.4-6.3), and greater support of traditional gender norms (β = 3.2, p = 0.002). The findings suggest that efforts are needed to address boys' behaviors related to the perpetration of multiple forms of violence and require explicit efforts to reduce perceived norms of violence perpetration as well as problematic gender attitudes (e.g., increasing support for gender equity) across boys' life contexts.

  1. Planning According to New Urbanism: the Ostadsara Neighborhood Case Study

    Directory of Open Access Journals (Sweden)

    Nader Zali

    2016-12-01

    Full Text Available The modern urbanism activities have led to rupture of previous spatial structure of neighborhoods and destruction of their identity. The New Urbanism Movement, as one of the successful models in urbanization field attempts to revive this lost national-social identity through the project of returning to traditional structure of neighborhoods by applying modern urbanization models and methods. The current paper aims at evaluation and analysis of “the Ostadsara neighborhood's organization based on new urbanism principles” and representation of solutions for planning a successful neighborhood center considering these principles. In this regard, various methods including library method, observation, photography, questionnaire and interview with users of the environment were utilized. The results from identification and assessment of weaknesses and strengths and specification and analysis of potential threats and opportunities shows the possibility of applying walkability, connectivity and integration, improvement of public transportation, improvement of architecture quality and urban design, maintenance and improvement of public and green open spaces, maintenance and strengthening the structure of traditional neighborhood units and using cooperation of Ostadsara neighborhood's inhabitants. Finally, the current study will represent appropriate strategies for changing the mentioned neighborhood into a desirable and prosperous one.

  2. Revisiting non-Gaussianity from non-attractor inflation models

    Science.gov (United States)

    Cai, Yi-Fu; Chen, Xingang; Namjoo, Mohammad Hossein; Sasaki, Misao; Wang, Dong-Gang; Wang, Ziwei

    2018-05-01

    Non-attractor inflation is known as the only single field inflationary scenario that can violate non-Gaussianity consistency relation with the Bunch-Davies vacuum state and generate large local non-Gaussianity. However, it is also known that the non-attractor inflation by itself is incomplete and should be followed by a phase of slow-roll attractor. Moreover, there is a transition process between these two phases. In the past literature, this transition was approximated as instant and the evolution of non-Gaussianity in this phase was not fully studied. In this paper, we follow the detailed evolution of the non-Gaussianity through the transition phase into the slow-roll attractor phase, considering different types of transition. We find that the transition process has important effect on the size of the local non-Gaussianity. We first compute the net contribution of the non-Gaussianities at the end of inflation in canonical non-attractor models. If the curvature perturbations keep evolving during the transition—such as in the case of smooth transition or some sharp transition scenarios—the Script O(1) local non-Gaussianity generated in the non-attractor phase can be completely erased by the subsequent evolution, although the consistency relation remains violated. In extremal cases of sharp transition where the super-horizon modes freeze immediately right after the end of the non-attractor phase, the original non-attractor result can be recovered. We also study models with non-canonical kinetic terms, and find that the transition can typically contribute a suppression factor in the squeezed bispectrum, but the final local non-Gaussianity can still be made parametrically large.

  3. Neighborhood Decline and the Economic Crisis (discussion paper)

    NARCIS (Netherlands)

    Zwiers, M.D.; Bolt, G.; Van Ham, M.; Van Kempen, R.

    2014-01-01

    Neighborhood decline is a complex and multidimensional process. National and regional variation in economic and political structures (including variety in national welfare state arrangements), combined with differences in neighborhood history, development and population composition, makes it

  4. Gaussian limit of compact spin systems

    International Nuclear Information System (INIS)

    Bellissard, J.; Angelis, G.F. de

    1981-01-01

    It is shown that the Wilson and Wilson-Villain U(1) models reproduce, in the low coupling limit, the gaussian lattice approximation of the Euclidean electromagnetic field. By the same methods it is also possible to prove that the plane rotator and the Villain model share a common gaussian behaviour in the low temperature limit. (Auth.)

  5. Gaussian cloning of coherent states with known phases

    International Nuclear Information System (INIS)

    Alexanian, Moorad

    2006-01-01

    The fidelity for cloning coherent states is improved over that provided by optimal Gaussian and non-Gaussian cloners for the subset of coherent states that are prepared with known phases. Gaussian quantum cloning duplicates all coherent states with an optimal fidelity of 2/3. Non-Gaussian cloners give optimal single-clone fidelity for a symmetric 1-to-2 cloner of 0.6826. Coherent states that have known phases can be cloned with a fidelity of 4/5. The latter is realized by a combination of two beam splitters and a four-wave mixer operated in the nonlinear regime, all of which are realized by interaction Hamiltonians that are quadratic in the photon operators. Therefore, the known Gaussian devices for cloning coherent states are extended when cloning coherent states with known phases by considering a nonbalanced beam splitter at the input side of the amplifier

  6. Non-Gaussian Methods for Causal Structure Learning.

    Science.gov (United States)

    Shimizu, Shohei

    2018-05-22

    Causal structure learning is one of the most exciting new topics in the fields of machine learning and statistics. In many empirical sciences including prevention science, the causal mechanisms underlying various phenomena need to be studied. Nevertheless, in many cases, classical methods for causal structure learning are not capable of estimating the causal structure of variables. This is because it explicitly or implicitly assumes Gaussianity of data and typically utilizes only the covariance structure. In many applications, however, non-Gaussian data are often obtained, which means that more information may be contained in the data distribution than the covariance matrix is capable of containing. Thus, many new methods have recently been proposed for using the non-Gaussian structure of data and inferring the causal structure of variables. This paper introduces prevention scientists to such causal structure learning methods, particularly those based on the linear, non-Gaussian, acyclic model known as LiNGAM. These non-Gaussian data analysis tools can fully estimate the underlying causal structures of variables under assumptions even in the presence of unobserved common causes. This feature is in contrast to other approaches. A simulated example is also provided.

  7. Gaussian polynomials and content ideal in trivial extensions

    International Nuclear Information System (INIS)

    Bakkari, C.; Mahdou, N.

    2006-12-01

    The goal of this paper is to exhibit a class of Gaussian non-coherent rings R (with zero-divisors) such that wdim(R) = ∞ and fPdim(R) is always at most one and also exhibits a new class of rings (with zerodivisors) which are neither locally Noetherian nor locally domain where Gaussian polynomials have a locally principal content. For this purpose, we study the possible transfer of the 'Gaussian' property and the property 'the content ideal of a Gaussian polynomial is locally principal' to various trivial extension contexts. This article includes a brief discussion of the scopes and limits of our result. (author)

  8. Quantifying entanglement in two-mode Gaussian states

    Science.gov (United States)

    Tserkis, Spyros; Ralph, Timothy C.

    2017-12-01

    Entangled two-mode Gaussian states are a key resource for quantum information technologies such as teleportation, quantum cryptography, and quantum computation, so quantification of Gaussian entanglement is an important problem. Entanglement of formation is unanimously considered a proper measure of quantum correlations, but for arbitrary two-mode Gaussian states no analytical form is currently known. In contrast, logarithmic negativity is a measure that is straightforward to calculate and so has been adopted by most researchers, even though it is a less faithful quantifier. In this work, we derive an analytical lower bound for entanglement of formation of generic two-mode Gaussian states, which becomes tight for symmetric states and for states with balanced correlations. We define simple expressions for entanglement of formation in physically relevant situations and use these to illustrate the problematic behavior of logarithmic negativity, which can lead to spurious conclusions.

  9. Optimal unitary dilation for bosonic Gaussian channels

    International Nuclear Information System (INIS)

    Caruso, Filippo; Eisert, Jens; Giovannetti, Vittorio; Holevo, Alexander S.

    2011-01-01

    A general quantum channel can be represented in terms of a unitary interaction between the information-carrying system and a noisy environment. In this paper the minimal number of quantum Gaussian environmental modes required to provide a unitary dilation of a multimode bosonic Gaussian channel is analyzed for both pure and mixed environments. We compute this quantity in the case of pure environment corresponding to the Stinespring representation and give an improved estimate in the case of mixed environment. The computations rely, on one hand, on the properties of the generalized Choi-Jamiolkowski state and, on the other hand, on an explicit construction of the minimal dilation for arbitrary bosonic Gaussian channel. These results introduce a new quantity reflecting ''noisiness'' of bosonic Gaussian channels and can be applied to address some issues concerning transmission of information in continuous variables systems.

  10. Graphical calculus for Gaussian pure states

    International Nuclear Information System (INIS)

    Menicucci, Nicolas C.; Flammia, Steven T.; Loock, Peter van

    2011-01-01

    We provide a unified graphical calculus for all Gaussian pure states, including graph transformation rules for all local and semilocal Gaussian unitary operations, as well as local quadrature measurements. We then use this graphical calculus to analyze continuous-variable (CV) cluster states, the essential resource for one-way quantum computing with CV systems. Current graphical approaches to CV cluster states are only valid in the unphysical limit of infinite squeezing, and the associated graph transformation rules only apply when the initial and final states are of this form. Our formalism applies to all Gaussian pure states and subsumes these rules in a natural way. In addition, the term 'CV graph state' currently has several inequivalent definitions in use. Using this formalism we provide a single unifying definition that encompasses all of them. We provide many examples of how the formalism may be used in the context of CV cluster states: defining the 'closest' CV cluster state to a given Gaussian pure state and quantifying the error in the approximation due to finite squeezing; analyzing the optimality of certain methods of generating CV cluster states; drawing connections between this graphical formalism and bosonic Hamiltonians with Gaussian ground states, including those useful for CV one-way quantum computing; and deriving a graphical measure of bipartite entanglement for certain classes of CV cluster states. We mention other possible applications of this formalism and conclude with a brief note on fault tolerance in CV one-way quantum computing.

  11. Mode entanglement of Gaussian fermionic states

    Science.gov (United States)

    Spee, C.; Schwaiger, K.; Giedke, G.; Kraus, B.

    2018-04-01

    We investigate the entanglement of n -mode n -partite Gaussian fermionic states (GFS). First, we identify a reasonable definition of separability for GFS and derive a standard form for mixed states, to which any state can be mapped via Gaussian local unitaries (GLU). As the standard form is unique, two GFS are equivalent under GLU if and only if their standard forms coincide. Then, we investigate the important class of local operations assisted by classical communication (LOCC). These are central in entanglement theory as they allow one to partially order the entanglement contained in states. We show, however, that there are no nontrivial Gaussian LOCC (GLOCC) among pure n -partite (fully entangled) states. That is, any such GLOCC transformation can also be accomplished via GLU. To obtain further insight into the entanglement properties of such GFS, we investigate the richer class of Gaussian stochastic local operations assisted by classical communication (SLOCC). We characterize Gaussian SLOCC classes of pure n -mode n -partite states and derive them explicitly for few-mode states. Furthermore, we consider certain fermionic LOCC and show how to identify the maximally entangled set of pure n -mode n -partite GFS, i.e., the minimal set of states having the property that any other state can be obtained from one state inside this set via fermionic LOCC. We generalize these findings also to the pure m -mode n -partite (for m >n ) case.

  12. Gaussian Mixture Model of Heart Rate Variability

    Science.gov (United States)

    Costa, Tommaso; Boccignone, Giuseppe; Ferraro, Mario

    2012-01-01

    Heart rate variability (HRV) is an important measure of sympathetic and parasympathetic functions of the autonomic nervous system and a key indicator of cardiovascular condition. This paper proposes a novel method to investigate HRV, namely by modelling it as a linear combination of Gaussians. Results show that three Gaussians are enough to describe the stationary statistics of heart variability and to provide a straightforward interpretation of the HRV power spectrum. Comparisons have been made also with synthetic data generated from different physiologically based models showing the plausibility of the Gaussian mixture parameters. PMID:22666386

  13. Learning conditional Gaussian networks

    DEFF Research Database (Denmark)

    Bøttcher, Susanne Gammelgaard

    This paper considers conditional Gaussian networks. The parameters in the network are learned by using conjugate Bayesian analysis. As conjugate local priors, we apply the Dirichlet distribution for discrete variables and the Gaussian-inverse gamma distribution for continuous variables, given...... a configuration of the discrete parents. We assume parameter independence and complete data. Further, to learn the structure of the network, the network score is deduced. We then develop a local master prior procedure, for deriving parameter priors in these networks. This procedure satisfies parameter...... independence, parameter modularity and likelihood equivalence. Bayes factors to be used in model search are introduced. Finally the methods derived are illustrated by a simple example....

  14. Neighborhood Environment and Cognition in Older Adults: A Systematic Review.

    Science.gov (United States)

    Besser, Lilah M; McDonald, Noreen C; Song, Yan; Kukull, Walter A; Rodriguez, Daniel A

    2017-08-01

    Some evidence suggests that treating vascular risk factors and performing mentally stimulating activities may delay cognitive impairment onset in older adults. Exposure to a complex neighborhood environment may be one mechanism to help delay cognitive decline. PubMed, Web of Science, and ProQuest Dissertation and Theses Global database were systematically reviewed, identifying 25 studies published from February 1, 1989 to March 5, 2016 (data synthesized, May 3, 2015 to October 7, 2016). The review was restricted to quantitative studies focused on: (1) neighborhood social and built environment and cognition; and (2) community-dwelling adults aged ≥45 years. The majority of studies were cross-sectional, U.S.-based, and found at least one significant association. The diversity of measures and neighborhood definitions limited the synthesis of findings in many instances. Evidence was moderately strong for an association between neighborhood SES and cognition, and modest for associations between neighborhood demographics, design, and destination accessibility and cognition. Most studies examining effect modification found significant associations, with some evidence for effect modification of the neighborhood SES-cognition association by individual-level SES. No studies had low risk of bias and many tested multiple associations that increased the chance of a statistically significant finding. Considering the studies to date, the evidence for an association between neighborhood characteristics and cognition is modest. Future studies should include longitudinal measures of neighborhood characteristics and cognition; examine potential effect modifiers, such as sex and disability; and study mediators that may help elucidate the biological mechanisms linking neighborhood environment and cognition. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  15. Two-photon optics of Bessel-Gaussian modes

    CSIR Research Space (South Africa)

    McLaren, M

    2013-09-01

    Full Text Available In this paper we consider geometrical two-photon optics of Bessel-Gaussian modes generated in spontaneous parametric down-conversion of a Gaussian pump beam. We provide a general theoretical expression for the orbital angular momentum (OAM) spectrum...

  16. Gaussian discriminating strength

    Science.gov (United States)

    Rigovacca, L.; Farace, A.; De Pasquale, A.; Giovannetti, V.

    2015-10-01

    We present a quantifier of nonclassical correlations for bipartite, multimode Gaussian states. It is derived from the Discriminating Strength measure, introduced for finite dimensional systems in Farace et al., [New J. Phys. 16, 073010 (2014), 10.1088/1367-2630/16/7/073010]. As the latter the new measure exploits the quantum Chernoff bound to gauge the susceptibility of the composite system with respect to local perturbations induced by unitary gates extracted from a suitable set of allowed transformations (the latter being identified by posing some general requirements). Closed expressions are provided for the case of two-mode Gaussian states obtained by squeezing or by linearly mixing via a beam splitter a factorized two-mode thermal state. For these density matrices, we study how nonclassical correlations are related with the entanglement present in the system and with its total photon number.

  17. Perceived Neighborhood Safety and Adolescent School Functioning

    Science.gov (United States)

    Martin-Storey, Alexa; Crosnoe, Robert

    2014-01-01

    This study examined the association between adolescents' perceptions of their neighborhoods' safety and multiple elements of their functioning in school with data on 15 year olds from the NICHD Study of Early Child Care and Youth Development (n = 924). In general, perceived neighborhood safety was more strongly associated with aspects of schooling…

  18. Short- and Long-Term Impacts of Neighborhood Built Environment on Self-Rated Health of Older Adults.

    Science.gov (United States)

    Spring, Amy

    2018-01-18

    Proximity to health care, healthy foods, and recreation is linked to improved health in older adults while deterioration of the built environment is a risk factor for poor health. Yet, it remains unclear whether individuals prone to good health self-select into favorable built environments and how long-term exposure to deteriorated environments impacts health. This study uses a longitudinal framework to address these questions. The study analyzes 3,240 Americans aged 45 or older from the Panel Study of Income Dynamics with good self-reported health at baseline, and follows them from 1999 to 2013. At each biennial survey wave, individual data are combined with data on services in the neighborhood of residence (defined as the zip code) from the Economic Census. The analysis overcomes the problem of residential self-selection by employing marginal structural models and inverse probability of treatment weights. Logistic regression estimates indicate that long-term exposure to neighborhood built environments that lack health-supportive services (e.g., physicians, pharmacies, grocery stores, senior centers, and recreational facilities) and are commercially declined (i.e., have a high density of liquor stores, pawn shops, and fast food outlets) increases the risk of fair/poor self-rated health compared to more average neighborhoods. Short-term exposure to the same environments as compared to average neighborhoods has no bearing on self-rated health after adjusting for self-selection. Results highlight the importance of expanding individuals' access to health-supportive services prior to their reaching old age, and expanding access for people unlikely to attain residence in service-dense neighborhoods. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Intergenerational Education Transmission: Neighborhood Quality and

    OpenAIRE

    Patacchini, Eleonora; Zenou, Yves

    2004-01-01

    Using cultural transmission, we develop a model that gives some microfoundation to the impact of residential neighborhood on children's educational attainment and then test it using the UK National Child Development Study. We find that, for high-educated parents, the better the quality of the neighborhood in terms of human capital, the higher the parent's involvement in children's education, indicating cultural complementarity. For high-educated parents, we also find that both parents' involv...

  20. Neighborhood disadvantage and ischemic stroke: the Cardiovascular Health Study (CHS).

    Science.gov (United States)

    Brown, Arleen F; Liang, Li-Jung; Vassar, Stefanie D; Stein-Merkin, Sharon; Longstreth, W T; Ovbiagele, Bruce; Yan, Tingjian; Escarce, José J

    2011-12-01

    Neighborhood characteristics may influence the risk of stroke and contribute to socioeconomic disparities in stroke incidence. The objectives of this study were to examine the relationship between neighborhood socioeconomic status and incident ischemic stroke and examine potential mediators of these associations. We analyzed data from 3834 whites and 785 blacks enrolled in the Cardiovascular Health Study, a multicenter, population-based, longitudinal study of adults ages≥65 years from 4 US counties. The primary outcome was adjudicated incident ischemic stroke. Neighborhood socioeconomic status was measured using a composite of 6 census tract variables. Race-stratified multilevel Cox proportional hazard models were constructed adjusted for sociodemographic, behavioral, and biological risk factors. Among whites, in models adjusted for sociodemographic characteristics, stroke hazard was significantly higher among residents of neighborhoods in the lowest compared with the highest neighborhood socioeconomic status quartile (hazard ratio, 1.32; 95% CI, 1.01-1.72) with greater attenuation of the hazard ratio after adjustment for biological risk factors (hazard ratio, 1.16; 0.88-1.52) than for behavioral risk factors (hazard ratio, 1.30; 0.99-1.70). Among blacks, we found no significant associations between neighborhood socioeconomic status and ischemic stroke. Higher risk of incident ischemic stroke was observed in the most disadvantaged neighborhoods among whites, but not among blacks. The relationship between neighborhood socioeconomic status and stroke among whites appears to be mediated more strongly by biological than behavioral risk factors.

  1. Superstatistical generalised Langevin equation: non-Gaussian viscoelastic anomalous diffusion

    Science.gov (United States)

    Ślęzak, Jakub; Metzler, Ralf; Magdziarz, Marcin

    2018-02-01

    Recent advances in single particle tracking and supercomputing techniques demonstrate the emergence of normal or anomalous, viscoelastic diffusion in conjunction with non-Gaussian distributions in soft, biological, and active matter systems. We here formulate a stochastic model based on a generalised Langevin equation in which non-Gaussian shapes of the probability density function and normal or anomalous diffusion have a common origin, namely a random parametrisation of the stochastic force. We perform a detailed analysis demonstrating how various types of parameter distributions for the memory kernel result in exponential, power law, or power-log law tails of the memory functions. The studied system is also shown to exhibit a further unusual property: the velocity has a Gaussian one point probability density but non-Gaussian joint distributions. This behaviour is reflected in the relaxation from a Gaussian to a non-Gaussian distribution observed for the position variable. We show that our theoretical results are in excellent agreement with stochastic simulations.

  2. Functional Dual Adaptive Control with Recursive Gaussian Process Model

    International Nuclear Information System (INIS)

    Prüher, Jakub; Král, Ladislav

    2015-01-01

    The paper deals with dual adaptive control problem, where the functional uncertainties in the system description are modelled by a non-parametric Gaussian process regression model. Current approaches to adaptive control based on Gaussian process models are severely limited in their practical applicability, because the model is re-adjusted using all the currently available data, which keeps growing with every time step. We propose the use of recursive Gaussian process regression algorithm for significant reduction in computational requirements, thus bringing the Gaussian process-based adaptive controllers closer to their practical applicability. In this work, we design a bi-criterial dual controller based on recursive Gaussian process model for discrete-time stochastic dynamic systems given in an affine-in-control form. Using Monte Carlo simulations, we show that the proposed controller achieves comparable performance with the full Gaussian process-based controller in terms of control quality while keeping the computational demands bounded. (paper)

  3. Back to Normal! Gaussianizing posterior distributions for cosmological probes

    Science.gov (United States)

    Schuhmann, Robert L.; Joachimi, Benjamin; Peiris, Hiranya V.

    2014-05-01

    We present a method to map multivariate non-Gaussian posterior probability densities into Gaussian ones via nonlinear Box-Cox transformations, and generalizations thereof. This is analogous to the search for normal parameters in the CMB, but can in principle be applied to any probability density that is continuous and unimodal. The search for the optimally Gaussianizing transformation amongst the Box-Cox family is performed via a maximum likelihood formalism. We can judge the quality of the found transformation a posteriori: qualitatively via statistical tests of Gaussianity, and more illustratively by how well it reproduces the credible regions. The method permits an analytical reconstruction of the posterior from a sample, e.g. a Markov chain, and simplifies the subsequent joint analysis with other experiments. Furthermore, it permits the characterization of a non-Gaussian posterior in a compact and efficient way. The expression for the non-Gaussian posterior can be employed to find analytic formulae for the Bayesian evidence, and consequently be used for model comparison.

  4. A New Neighborhood Every Fall: Aging in Place in a College Town.

    Science.gov (United States)

    Powell, Kathleen H

    Older adults who live in residential neighborhoods adjacent to college and university campuses have a unique experience that makes them vulnerable to marginalization and displacement. As these neighborhoods become increasingly dominated by college students living in rental properties, older adults find themselves in the minority in a neighborhood where they have lived for many years. In addition, these neighborhoods are attractive to universities, city governments, and private companies for their development potential, which can result in gentrification. A year-long ethnographic study of a campus-adjacent neighborhood in a small US college town that is home to a medium-sized public university sheds light on the relationships between members of 5 stakeholder groups that have a vested interest in the neighborhood. The study highlights the need for additional research on different types of neighborhoods and their effects on aging in place in addition to outlining social work interventions in campus-adjacent neighborhoods that are designed to enhance these intergenerational spaces.

  5. On the Shaker Simulation of Wind-Induced Non-Gaussian Random Vibration

    Directory of Open Access Journals (Sweden)

    Fei Xu

    2016-01-01

    Full Text Available Gaussian signal is produced by ordinary random vibration controllers to test the products in the laboratory, while the field data is usually non-Gaussian. Two methodologies are presented in this paper for shaker simulation of wind-induced non-Gaussian vibration. The first methodology synthesizes the non-Gaussian signal offline and replicates it on the shaker in the Time Waveform Replication (TWR mode. A new synthesis method is used to model the non-Gaussian signal as a Gaussian signal multiplied by an amplitude modulation function (AMF. A case study is presented to show that the synthesized non-Gaussian signal has the same power spectral density (PSD, probability density function (PDF, and loading cycle distribution (LCD as the field data. The second methodology derives a damage equivalent Gaussian signal from the non-Gaussian signal based on the fatigue damage spectrum (FDS and the extreme response spectrum (ERS and reproduces it on the shaker in the closed-loop frequency domain control mode. The PSD level and the duration time of the derived Gaussian signal can be manipulated for accelerated testing purpose. A case study is presented to show that the derived PSD matches the damage potential of the non-Gaussian environment for both fatigue and peak response.

  6. Neighborhood perceptions and allostatic load : Evidence from Denmark

    NARCIS (Netherlands)

    van Deurzen, I.A.; Hulvej Rod, Naja; Christensen, Ulla; Hansen, Åse Marie; Lund, Rikke; Dich, Nadya

    2016-01-01

    An influential argument explaining why living in certain neighborhoods can become harmful to one's health maintains that individuals can perceive certain characteristics of the neighborhood as threatening and the prolonged exposure to a threatening environment could induce chronic stress. Following

  7. Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents

    OpenAIRE

    Lenhart, Clare M.; Wiemken, Andrew; Hanlon, Alexandra; Perkett, Mackenzie; Patterson, Freda

    2017-01-01

    Abstract Background A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students. Methods Using cross-sectional, weighted data...

  8. Optimal multicopy asymmetric Gaussian cloning of coherent states

    International Nuclear Information System (INIS)

    Fiurasek, Jaromir; Cerf, Nicolas J.

    2007-01-01

    We investigate the asymmetric Gaussian cloning of coherent states which produces M copies from N input replicas in such a way that the fidelity of each copy may be different. We show that the optimal asymmetric Gaussian cloning can be performed with a single phase-insensitive amplifier and an array of beam splitters. We obtain a simple analytical expression characterizing the set of optimal asymmetric Gaussian cloning machines and prove the optimality of these cloners using the formalism of Gaussian completely positive maps and semidefinite programming techniques. We also present an alternative implementation of the asymmetric cloning machine where the phase-insensitive amplifier is replaced with a beam splitter, heterodyne detector, and feedforward

  9. Optimal multicopy asymmetric Gaussian cloning of coherent states

    Science.gov (United States)

    Fiurášek, Jaromír; Cerf, Nicolas J.

    2007-05-01

    We investigate the asymmetric Gaussian cloning of coherent states which produces M copies from N input replicas in such a way that the fidelity of each copy may be different. We show that the optimal asymmetric Gaussian cloning can be performed with a single phase-insensitive amplifier and an array of beam splitters. We obtain a simple analytical expression characterizing the set of optimal asymmetric Gaussian cloning machines and prove the optimality of these cloners using the formalism of Gaussian completely positive maps and semidefinite programming techniques. We also present an alternative implementation of the asymmetric cloning machine where the phase-insensitive amplifier is replaced with a beam splitter, heterodyne detector, and feedforward.

  10. Safety in numbers: does perceived safety mediate associations between the neighborhood social environment and physical activity among women living in disadvantaged neighborhoods?

    Science.gov (United States)

    Timperio, Anna; Veitch, Jenny; Carver, Alison

    2015-05-01

    The aim of this study is to examine associations between the neighborhood social environment and leisure-time physical activity (LTPA)(1) and walking among women, and whether these associations are mediated by perceived personal safety. Women (n = 3784) living in disadvantaged urban and rural neighborhoods within Victoria, Australia completed a self-administered survey on five social environment variables (neighborhood crime, neighborhood violence, seeing others walking and exercising in the neighborhood, social trust/cohesion), perceived personal safety, and their physical activity in 2007/8. Linear regression analyses examined associations between social environment variables and LTPA and walking. Potential mediating pathways were assessed using the product-of-coefficients test. Moderated mediation by urban/rural residence was examined. Each social environment variable was positively associated with engaging in at least 150 min/week of LTPA (OR = 1.16 to 1.56). Only two social environment variables, seeing others walking (OR = 1.45) and exercising (OR = 1.31), were associated with ≥ 150 min/week of walking. Perceived personal safety mediated all associations. Stronger mediation was found in urban areas for crime, violence and social trust/cohesion. The neighborhood social environment is an important influence on physical activity among women living in disadvantaged areas. Feelings of personal safety should not be included in composite or aggregate scores relating to the social environment. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. How Gaussian can our Universe be?

    Energy Technology Data Exchange (ETDEWEB)

    Cabass, G. [Physics Department and INFN, Università di Roma ' ' La Sapienza' ' , P.le Aldo Moro 2, 00185, Rome (Italy); Pajer, E. [Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Princetonplein 5, 3584 CC Utrecht (Netherlands); Schmidt, F., E-mail: giovanni.cabass@roma1.infn.it, E-mail: e.pajer@uu.nl, E-mail: fabians@mpa-garching.mpg.de [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany)

    2017-01-01

    Gravity is a non-linear theory, and hence, barring cancellations, the initial super-horizon perturbations produced by inflation must contain some minimum amount of mode coupling, or primordial non-Gaussianity. In single-field slow-roll models, where this lower bound is saturated, non-Gaussianity is controlled by two observables: the tensor-to-scalar ratio, which is uncertain by more than fifty orders of magnitude; and the scalar spectral index, or tilt, which is relatively well measured. It is well known that to leading and next-to-leading order in derivatives, the contributions proportional to the tilt disappear from any local observable, and suspicion has been raised that this might happen to all orders, allowing for an arbitrarily low amount of primordial non-Gaussianity. Employing Conformal Fermi Coordinates, we show explicitly that this is not the case. Instead, a contribution of order the tilt appears in local observables. In summary, the floor of physical primordial non-Gaussianity in our Universe has a squeezed-limit scaling of k {sub ℓ}{sup 2}/ k {sub s} {sup 2}, similar to equilateral and orthogonal shapes, and a dimensionless amplitude of order 0.1 × ( n {sub s}−1).

  12. How Gaussian can our Universe be?

    Science.gov (United States)

    Cabass, G.; Pajer, E.; Schmidt, F.

    2017-01-01

    Gravity is a non-linear theory, and hence, barring cancellations, the initial super-horizon perturbations produced by inflation must contain some minimum amount of mode coupling, or primordial non-Gaussianity. In single-field slow-roll models, where this lower bound is saturated, non-Gaussianity is controlled by two observables: the tensor-to-scalar ratio, which is uncertain by more than fifty orders of magnitude; and the scalar spectral index, or tilt, which is relatively well measured. It is well known that to leading and next-to-leading order in derivatives, the contributions proportional to the tilt disappear from any local observable, and suspicion has been raised that this might happen to all orders, allowing for an arbitrarily low amount of primordial non-Gaussianity. Employing Conformal Fermi Coordinates, we show explicitly that this is not the case. Instead, a contribution of order the tilt appears in local observables. In summary, the floor of physical primordial non-Gaussianity in our Universe has a squeezed-limit scaling of kl2/ks2, similar to equilateral and orthogonal shapes, and a dimensionless amplitude of order 0.1 × (ns-1).

  13. Healthy and Unhealthy Food Prices across Neighborhoods and Their Association with Neighborhood Socioeconomic Status and Proportion Black/Hispanic.

    Science.gov (United States)

    Kern, David M; Auchincloss, Amy H; Robinson, Lucy F; Stehr, Mark F; Pham-Kanter, Genevieve

    2017-08-01

    This paper evaluates variation in food prices within and between neighborhoods to improve our understanding of access to healthy foods in urbanized areas and potential economic incentives and barriers to consuming a higher-quality diet. Prices of a selection of healthier foods (dairy, fruit juice, and frozen vegetables) and unhealthy foods (soda, sweets, and salty snacks) were obtained from 1953 supermarkets across the USA during 2009-2012 and were linked to census block group socio-demographics. Analyses evaluated associations between neighborhood SES and proportion Black/Hispanic and the prices of healthier and unhealthy foods, and the relative price of healthier foods compared with unhealthy foods (healthy-to-unhealthy price ratio). Linear hierarchical regression models were used to explore geospatial variation and adjust for confounders. Overall, the price of healthier foods was nearly twice as high as the price of unhealthy foods ($0.590 vs $0.298 per serving; healthy-to-unhealthy price ratio of 1.99). This trend was consistent across all neighborhood characteristics. After adjusting for covariates, no association was found between food prices (healthy, unhealthy, or the healthy-to-unhealthy ratio) and neighborhood SES. Similarly, there was no association between the proportion Black/Hispanic and healthier food price, a very small positive association with unhealthy price, and a modest negative association with the healthy-to-unhealthy ratio. No major differences were seen in food prices across levels of neighborhood SES and proportion Black/Hispanic; however, the price of healthier food was twice as expensive as unhealthy food per serving on average.

  14. A systematic review of relations between neighborhoods and mental health.

    Science.gov (United States)

    Truong, Khoa D; Ma, Sai

    2006-09-01

    The relationship between neighborhood characteristics and resident mental health has been widely investigated in individual studies in recent years, but this literature is not adequately reviewed. To systematically review relevant individual research of the relation between neighborhoods and adult mental health by identifying and synthesizing all relevant studies in this literature. We conducted an electronic search with PubMed and PsycINFO, and manual reference-checking, resulting in 8,562 screened studies of which 29 were selected. Studies were included in the main synthesis if they (i) were published in English in peer reviewed journals; (ii) had relevant definitions and measures of neighborhood characteristics; (iii) utilized standardized measures of adult mental health; (iv) controlled for individual characteristics; (v) reported quantitative results; and, (vi) studied a population in a developed country. We focused on two key areas within this literature: the methodologies utilized to study neighborhood effects and quantitative results. With regard to the former, we examined five major issues: (i) definitions and measures of neighborhoods; (ii) definitions and measures of mental health; (iii) controls for individual level characteristics; (iv) conceptual models; and (v) analytical models. As for quantitative results, the relation was reviewed by types of neighborhood characteristics. We summarized general quantitative findings and drew common conclusions across groups of studies. 27/29 studies found statistically significant association between mental health and at least one measure of neighborhood characteristics, after adjusting for individual factors. This association was evident for all types of neighborhood features, varying from sociodemographic characteristics to physical environment, and from objective to subjective measures. Neighborhood effects were weakened when adding individual-level characteristics into the regression models, and were generally

  15. Gaussian Mixture Random Coefficient model based framework for SHM in structures with time-dependent dynamics under uncertainty

    Science.gov (United States)

    Avendaño-Valencia, Luis David; Fassois, Spilios D.

    2017-12-01

    The problem of vibration-based damage diagnosis in structures characterized by time-dependent dynamics under significant environmental and/or operational uncertainty is considered. A stochastic framework consisting of a Gaussian Mixture Random Coefficient model of the uncertain time-dependent dynamics under each structural health state, proper estimation methods, and Bayesian or minimum distance type decision making, is postulated. The Random Coefficient (RC) time-dependent stochastic model with coefficients following a multivariate Gaussian Mixture Model (GMM) allows for significant flexibility in uncertainty representation. Certain of the model parameters are estimated via a simple procedure which is founded on the related Multiple Model (MM) concept, while the GMM weights are explicitly estimated for optimizing damage diagnostic performance. The postulated framework is demonstrated via damage detection in a simple simulated model of a quarter-car active suspension with time-dependent dynamics and considerable uncertainty on the payload. Comparisons with a simpler Gaussian RC model based method are also presented, with the postulated framework shown to be capable of offering considerable improvement in diagnostic performance.

  16. Neighborhood crime and access to health-enabling resources in Chicago

    Directory of Open Access Journals (Sweden)

    Elizabeth L. Tung

    2018-03-01

    Full Text Available Neighborhood crime may be an important social determinant of health in many high-poverty, urban communities, yet little is known about its relationship with access to health-enabling resources. We recruited an address-based probability sample of 267 participants (ages ≥35 years on Chicago's South Side between 2012 and 2013. Participants were queried about their perceptions of neighborhood safety and prior experiences of neighborhood crime. Survey data were paired to a comprehensive, directly-observed census of the built environment on the South Side of Chicago. Multivariable logistic regression models were used to examine access to health-enabling resources (potential and realized access as a function of neighborhood crime (self-reported neighborhood safety and prior experience of theft or property crime, adjusting for sociodemographic characteristics and self-reported health status. Low potential access was defined as a resident having nearest resources >1 mile from home; poor realized access was defined as bypassing nearby potential resources to use resources >1 mile from home. Poor neighborhood safety was associated with low potential access to large grocery stores (AOR = 1.73, 95% CI = 1.04, 2.87, pharmacies (AOR = 2.24, 95% CI = 1.33, 3.77, and fitness resources (AOR = 1.93, 95% CI = 1.15, 3.24, but not small grocery stores. Any prior experience of neighborhood crime was associated with higher adjusted odds of bypassing nearby pharmacies (AOR = 3.78, 95% CI = 1.11, 12.87. Neighborhood crime may be associated with important barriers to accessing health-enabling resources in urban communities with high rates of crime. Keywords: Built environment, Neighborhood crime, Access to resources, Social determinants of health, Obesity, Hypertension

  17. Boltzmann-Gaussian transition under specific noise effect

    International Nuclear Information System (INIS)

    Anh, Chu Thuy; Lan, Nguyen Tri; Viet, Nguyen Ai

    2014-01-01

    It is observed that a short time data set of market returns presents almost symmetric Boltzmann distribution whereas a long time data set tends to show a Gaussian distribution. To understand this universal phenomenon, many hypotheses which are spreading in a wide range of interdisciplinary research were proposed. In current work, the effects of background fluctuations on symmetric Boltzmann distribution is investigated. The numerical calculation is performed to show that the Gaussian noise may cause the transition from initial Boltzmann distribution to Gaussian one. The obtained results would reflect non-dynamic nature of the transition under consideration.

  18. Resurgent Ethnicity among Asian Americans: Ethnic Neighborhood Context and Health

    Science.gov (United States)

    Walton, Emily

    2012-01-01

    In this study I investigate the associations of neighborhood socioeconomic and social environments with the health of Asian Americans living in both Asian ethnic neighborhoods and non-Asian neighborhoods. I use a sample of 1962 Asian Americans from the National Latino and Asian American Study (NLAAS, 2003-04). Three key findings emerge. First,…

  19. Neighborhood Environmental Health and Premature Death From Cardiovascular Disease.

    Science.gov (United States)

    Gaglioti, Anne H; Xu, Junjun; Rollins, Latrice; Baltrus, Peter; O'Connell, Laura Kathryn; Cooper, Dexter L; Hopkins, Jammie; Botchwey, Nisha D; Akintobi, Tabia Henry

    2018-02-01

    Cardiovascular disease (CVD) is the leading cause of death in the United States and disproportionately affects racial/ethnic minority groups. Healthy neighborhood conditions are associated with increased uptake of health behaviors that reduce CVD risk, but minority neighborhoods often have poor food access and poor walkability. This study tested the community-driven hypothesis that poor access to food at the neighborhood level and poor neighborhood walkability are associated with racial disparities in premature deaths from CVD. We examined the relationship between neighborhood-level food access and walkability on premature CVD mortality rates at the census tract level for the city of Atlanta using multivariable logistic regression models. We produced maps to illustrate premature CVD mortality, food access, and walkability by census tract for the city. We found significant racial differences in premature CVD mortality rates and geographic disparities in food access and walkability among census tracts in Atlanta. Improved food access and walkability were associated with reduced overall premature CVD mortality in unadjusted models, but this association did not persist in models adjusted for census tract population composition and poverty. Census tracts with high concentrations of minority populations had higher levels of poor food access, poor walkability, and premature CVD mortality. This study highlights disparities in premature CVD mortality and neighborhood food access and walkability at the census tract level in the city of Atlanta. Improving food access may have differential effects for subpopulations living in the same area. These results can be used to calibrate neighborhood-level interventions, and they highlight the need to examine race-specific health outcomes.

  20. Neighborhood perceptions and allostatic load: Evidence from Denmark.

    Science.gov (United States)

    van Deurzen, Ioana; Rod, Naja Hulvej; Christensen, Ulla; Hansen, Åse Marie; Lund, Rikke; Dich, Nadya

    2016-07-01

    An influential argument explaining why living in certain neighborhoods can become harmful to one's health maintains that individuals can perceive certain characteristics of the neighborhood as threatening and the prolonged exposure to a threatening environment could induce chronic stress. Following this line of argumentation, in the present study we test whether subjective perceptions of neighborhood characteristics relate to an objective measure of stress-related physiological functioning, namely allostatic load (AL). We use a large dataset of 5280 respondents living in different regions of Denmark and we account for two alternative mechanisms, i.e., the objective characteristics of the living environment and the socio-economic status of individuals. Our results support the chronic stress mechanisms linking neighborhood quality to health. Heightened perceptions of disorder and pollution were found related to AL and this relationship was particularly robust for women. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Hybrid [{sup 18}F]-FDG PET/MRI including non-Gaussian diffusion-weighted imaging (DWI): Preliminary results in non-small cell lung cancer (NSCLC)

    Energy Technology Data Exchange (ETDEWEB)

    Heusch, Philipp [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Köhler, Jens [Univ Duisburg-Essen, Medical Faculty, Department of Medical Oncology, D-45147 Essen (Germany); Wittsack, Hans-Joerg [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Heusner, Till A., E-mail: Heusner@med.uni-duesseldorf.de [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Buchbender, Christian [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany); Poeppel, Thorsten D. [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, D-45147 Essen (Germany); Nensa, Felix; Wetter, Axel [Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, D-45147 Essen (Germany); Gauler, Thomas [Univ Duisburg-Essen, Medical Faculty, Department of Medical Oncology, D-45147 Essen (Germany); Hartung, Verena [Univ Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, D-45147 Essen (Germany); Lanzman, Rotem S. [Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf (Germany)

    2013-11-01

    Purpose: To assess the feasibility of non-Gaussian DWI as part of a FDG-PET/MRI protocol in patients with histologically proven non-small cell lung cancer. Material and methods: 15 consecutive patients with histologically proven NSCLC (mean age 61 ± 11 years) were included in this study and underwent whole-body FDG-PET/MRI following whole-body FDG-PET/CT. As part of the whole-body FDG-PET/MRI protocol, an EPI-sequence with 5 b-values (0, 100, 500, 1000 and 2000 s/mm{sup 2}) was acquired for DWI of the thorax during free-breathing. Volume of interest (VOI) measurements were performed to determine the maximum and mean standardized uptake value (SUV{sub max}; SUV{sub mean}). A region of interest (ROI) was manually drawn around the tumor on b = 0 images and then transferred to the corresponding parameter maps to assess ADC{sub mono}, D{sub app} and K{sub app}. To assess the goodness of the mathematical fit R{sup 2} was calculated for monoexponential and non-Gaussian analysis. Spearman's correlation coefficients were calculated to compare SUV values and diffusion coefficients. A Student's t-test was performed to compare the monoexponential and non-Gaussian diffusion fitting (R{sup 2}). Results: T staging was equal between FDG-PET/CT and FDG-PET/MRI in 12 of 15 patients. For NSCLC, mean ADC{sub mono} was 2.11 ± 1.24 × 10{sup −3} mm{sup 2}/s, D{sub app} was 2.46 ± 1.29 × 10{sup −3} mm{sup 2}/s and mean K{sub app} was 0.70 ± 0.21. The non-Gaussian diffusion analysis (R{sup 2} = 0.98) provided a significantly better mathematical fitting to the DWI signal decay than the monoexponetial analysis (R{sup 2} = 0.96) (p < 0.001). SUV{sub max} and SUV{sub mean} of NSCLC was 13.5 ± 7.6 and 7.9 ± 4.3 for FDG-PET/MRI. ADC{sub mono} as well as D{sub app} exhibited a significant inverse correlation with the SUV{sub max} (ADC{sub mono}: R = −0.67; p < 0.01; D{sub app}: R = −0.69; p < 0.01) as well as with SUV{sub mean} assessed by FDG-PET/MRI (ADC{sub mono}: R

  2. The Digital Hood: Social Media Use among Youth in Disadvantaged Neighborhoods.

    Science.gov (United States)

    Stevens, Robin; Gilliard-Matthews, Stacia; Dunaev, Jamie; Woods, Marcus; Brawner, Bridgette M

    2017-06-01

    This study examines the role of social media in the lives of youth living in disadvantaged neighborhoods. Feminist Standpoint theory, which privileges the voices of marginalized communities in understanding social phenomena, suggests that youth at the margins have specific knowledge that helps us understand social media more broadly. We conducted semi-structured interviews with 30 females and 30 males aged 13 to 24 about their social worlds and neighborhoods, both on- and offline. The findings reveal a dynamic and somewhat concerning interplay between the geographic neighborhood and the digital neighborhood, whereby negative social interactions in the geographic neighborhood are reproduced and amplified on social media.

  3. Gaussian sum rules for optical functions

    International Nuclear Information System (INIS)

    Kimel, I.

    1981-12-01

    A new (Gaussian) type of sum rules (GSR) for several optical functions, is presented. The functions considered are: dielectric permeability, refractive index, energy loss function, rotatory power and ellipticity (circular dichroism). While reducing to the usual type of sum rules in a certain limit, the GSR contain in general, a Gaussian factor that serves to improve convergence. GSR might be useful in analysing experimental data. (Author) [pt

  4. Approximation problems with the divergence criterion for Gaussian variablesand Gaussian processes

    NARCIS (Netherlands)

    A.A. Stoorvogel; J.H. van Schuppen (Jan)

    1996-01-01

    textabstractSystem identification for stationary Gaussian processes includes an approximation problem. Currently the subspace algorithm for this problem enjoys much attention. This algorithm is based on a transformation of a finite time series to canonical variable form followed by a truncation.

  5. Gaussian processes for machine learning.

    Science.gov (United States)

    Seeger, Matthias

    2004-04-01

    Gaussian processes (GPs) are natural generalisations of multivariate Gaussian random variables to infinite (countably or continuous) index sets. GPs have been applied in a large number of fields to a diverse range of ends, and very many deep theoretical analyses of various properties are available. This paper gives an introduction to Gaussian processes on a fairly elementary level with special emphasis on characteristics relevant in machine learning. It draws explicit connections to branches such as spline smoothing models and support vector machines in which similar ideas have been investigated. Gaussian process models are routinely used to solve hard machine learning problems. They are attractive because of their flexible non-parametric nature and computational simplicity. Treated within a Bayesian framework, very powerful statistical methods can be implemented which offer valid estimates of uncertainties in our predictions and generic model selection procedures cast as nonlinear optimization problems. Their main drawback of heavy computational scaling has recently been alleviated by the introduction of generic sparse approximations.13,78,31 The mathematical literature on GPs is large and often uses deep concepts which are not required to fully understand most machine learning applications. In this tutorial paper, we aim to present characteristics of GPs relevant to machine learning and to show up precise connections to other "kernel machines" popular in the community. Our focus is on a simple presentation, but references to more detailed sources are provided.

  6. Palm distributions for log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus

    This paper reviews useful results related to Palm distributions of spatial point processes and provides a new result regarding the characterization of Palm distributions for the class of log Gaussian Cox processes. This result is used to study functional summary statistics for a log Gaussian Cox...

  7. Building Community: The Neighborhood Context of Social Organization

    Science.gov (United States)

    Swaroop, Sapna; Morenoff, Jeffrey D.

    2006-01-01

    This study explores how neighborhood context influences participation in local social organization through a multilevel-spatial analysis of residents in Chicago neighborhoods. We construct a typology of community participation based on two dimensions: instrumental vs. expressive motivations for participation and formal vs. informal modes of…

  8. Neighborhood Processes, Self-Efficacy, and Adolescent Mental Health

    Science.gov (United States)

    Dupere, Veronique; Leventhal, Tama; Vitaro, Frank

    2012-01-01

    Self-efficacy beliefs are central to mental health. Because adolescents' neighborhoods shape opportunities for experiences of control, predictability, and safety, we propose that neighborhood conditions are associated with adolescents' self-efficacy and, in turn, their internalizing problems (i.e., depression/anxiety symptoms). We tested these…

  9. Contemporary Neighborhood Theories: Integration versus Romance and Reaction.

    Science.gov (United States)

    Stever, James A.

    1978-01-01

    This paper discusses the integrative, romantic, and reactive theories of neighborhood government within the context of the urban reform movement and argues that the integrative theory is the one best suited for an effective political relationship between the neighborhood and the greater metropolis. (EB)

  10. Neighborhood walkability and active travel (walking and cycling) in New York City.

    Science.gov (United States)

    Freeman, Lance; Neckerman, Kathryn; Schwartz-Soicher, Ofira; Quinn, James; Richards, Catherine; Bader, Michael D M; Lovasi, Gina; Jack, Darby; Weiss, Christopher; Konty, Kevin; Arno, Peter; Viola, Deborah; Kerker, Bonnie; Rundle, Andrew G

    2013-08-01

    Urban planners have suggested that built environment characteristics can support active travel (walking and cycling) and reduce sedentary behavior. This study assessed whether engagement in active travel is associated with neighborhood walkability measured for zip codes in New York City. Data were analyzed on engagement in active travel and the frequency of walking or biking ten blocks or more in the past month, from 8,064 respondents to the New York City 2003 Community Health Survey (CHS). A neighborhood walkability scale that measures: residential, intersection, and subway stop density; land use mix; and the ratio of retail building floor area to retail land area was calculated for each zip code. Data were analyzed using zero-inflated negative binomial regression incorporating survey sample weights and adjusting for respondents' sociodemographic characteristics. Overall, 44 % of respondents reported no episodes of active travel and among those who reported any episode, the mean number was 43.2 episodes per month. Comparing the 75th to the 25th percentile of zip code walkability, the odds ratio for reporting zero episodes of active travel was 0.71 (95 % CI 0.61, 0.83) and the exponentiated beta coefficient for the count of episodes of active travel was 1.13 (95 % CI 1.06, 1.21). Associations between lower walkability and reporting zero episodes of active travel were significantly stronger for non-Hispanic Whites as compared to non-Hispanic Blacks and to Hispanics and for those living in higher income zip codes. The results suggest that neighborhood walkability is associated with higher engagement in active travel.

  11. Making tensor factorizations robust to non-gaussian noise.

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Eric C. (Rice University, Houston, TX); Kolda, Tamara Gibson

    2011-03-01

    Tensors are multi-way arrays, and the CANDECOMP/PARAFAC (CP) tensor factorization has found application in many different domains. The CP model is typically fit using a least squares objective function, which is a maximum likelihood estimate under the assumption of independent and identically distributed (i.i.d.) Gaussian noise. We demonstrate that this loss function can be highly sensitive to non-Gaussian noise. Therefore, we propose a loss function based on the 1-norm because it can accommodate both Gaussian and grossly non-Gaussian perturbations. We also present an alternating majorization-minimization (MM) algorithm for fitting a CP model using our proposed loss function (CPAL1) and compare its performance to the workhorse algorithm for fitting CP models, CP alternating least squares (CPALS).

  12. Integration of non-Gaussian fields

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Mohr, Gunnar; Hoffmeyer, Pernille

    1996-01-01

    The limitations of the validity of the central limit theorem argument as applied to definite integrals of non-Gaussian random fields are empirically explored by way of examples. The purpose is to investigate in specific cases whether the asymptotic convergence to the Gaussian distribution is fast....... and Randrup-Thomsen, S. Reliability of silo ring under lognormal stochastic pressure using stochastic interpolation. Proc. IUTAM Symp., Probabilistic Structural Mechanics: Advances in Structural Reliability Methods, San Antonio, TX, USA, June 1993 (eds.: P. D. Spanos & Y.-T. Wu) pp. 134-162. Springer, Berlin...

  13. Estimators for local non-Gaussianities

    International Nuclear Information System (INIS)

    Creminelli, P.; Senatore, L.; Zaldarriaga, M.

    2006-05-01

    We study the Likelihood function of data given f NL for the so-called local type of non-Gaussianity. In this case the curvature perturbation is a non-linear function, local in real space, of a Gaussian random field. We compute the Cramer-Rao bound for f NL and show that for small values of f NL the 3- point function estimator saturates the bound and is equivalent to calculating the full Likelihood of the data. However, for sufficiently large f NL , the naive 3-point function estimator has a much larger variance than previously thought. In the limit in which the departure from Gaussianity is detected with high confidence, error bars on f NL only decrease as 1/ln N pix rather than N pix -1/2 as the size of the data set increases. We identify the physical origin of this behavior and explain why it only affects the local type of non- Gaussianity, where the contribution of the first multipoles is always relevant. We find a simple improvement to the 3-point function estimator that makes the square root of its variance decrease as N pix -1/2 even for large f NL , asymptotically approaching the Cramer-Rao bound. We show that using the modified estimator is practically equivalent to computing the full Likelihood of f NL given the data. Thus other statistics of the data, such as the 4-point function and Minkowski functionals, contain no additional information on f NL . In particular, we explicitly show that the recent claims about the relevance of the 4-point function are not correct. By direct inspection of the Likelihood, we show that the data do not contain enough information for any statistic to be able to constrain higher order terms in the relation between the Gaussian field and the curvature perturbation, unless these are orders of magnitude larger than the size suggested by the current limits on f NL . (author)

  14. Do Neighborhood Characteristics in Amsterdam Influence Adiposity at Preschool Age?

    Directory of Open Access Journals (Sweden)

    E. Jessica Hrudey

    2015-05-01

    Full Text Available Background: Neighborhood characteristics may contribute to adiposity in young children, but results in the current literature are inconsistent. This study aimed to investigate whether objective (socioeconomic status (SES and subjective (perceived safety, satisfaction with green spaces and perceived physical disorder neighborhood characteristics directly influence child adiposity (as measured by BMI, percent body fat (%BF and waist-to-height ratio (WHtR. Methods: Data on child BMI, %BF and WHtR were obtained from the Amsterdam Born Children and their Development cohort at 5–6 years of age. Three thousand four hundred and sixty nine (3469 children were included in the analyses. Mixed models, using random intercepts for postal code area to account for neighborhood clustering effects, were used to analyze the relationships of interest. Results: Associations were observed for both perceived safety and neighborhood SES with %BF after adjustment for maternal education and ethnicity. All relationships were eliminated with the inclusion of individual covariates and parental BMI into the models. Conclusions: In general, child adiposity at age 5–6 years was not independently associated with neighborhood characteristics, although a small relationship between child %BF and both neighborhood SES and perceived safety cannot be ruled out. At this young age, familial and individual factors probably play a more important role in influencing child adiposity than neighborhood characteristics.

  15. Cognitive Aspects of Regularity Exhibit When Neighborhood Disappears

    Science.gov (United States)

    Chen, Sau-Chin; Hu, Jon-Fan

    2015-01-01

    Although regularity refers to the compatibility between pronunciation of character and sound of phonetic component, it has been suggested as being part of consistency, which is defined by neighborhood characteristics. Two experiments demonstrate how regularity effect is amplified or reduced by neighborhood characteristics and reveals the…

  16. Neighborhood size and local geographic variation of health and social determinants

    Directory of Open Access Journals (Sweden)

    Emch Michael

    2005-06-01

    Full Text Available Abstract Background Spatial filtering using a geographic information system (GIS is often used to smooth health and ecological data. Smoothing disease data can help us understand local (neighborhood geographic variation and ecological risk of diseases. Analyses that use small neighborhood sizes yield individualistic patterns and large sizes reveal the global structure of data where local variation is obscured. Therefore, choosing an optimal neighborhood size is important for understanding ecological associations with diseases. This paper uses Hartley's test of homogeneity of variance (Fmax as a methodological solution for selecting optimal neighborhood sizes. The data from a study area in Vietnam are used to test the suitability of this method. Results The Hartley's Fmax test was applied to spatial variables for two enteric diseases and two socioeconomic determinants. Various neighbourhood sizes were tested by using a two step process to implement the Fmaxtest. First the variance of each neighborhood was compared to the highest neighborhood variance (upper, Fmax1 and then they were compared with the lowest neighborhood variance (lower, Fmax2. A significant value of Fmax1 indicates that the neighborhood does not reveal the global structure of data, and in contrast, a significant value in Fmax2 implies that the neighborhood data are not individualistic. The neighborhoods that are between the lower and the upper limits are the optimal neighbourhood sizes. Conclusion The results of tests provide different neighbourhood sizes for different variables suggesting that optimal neighbourhood size is data dependent. In ecology, it is well known that observation scales may influence ecological inference. Therefore, selecting optimal neigborhood size is essential for understanding disease ecologies. The optimal neighbourhood selection method that is tested in this paper can be useful in health and ecological studies.

  17. Improving Mental Health Through the Regeneration of Deprived Neighborhoods: A Natural Experiment.

    Science.gov (United States)

    White, James; Greene, Giles; Farewell, Daniel; Dunstan, Frank; Rodgers, Sarah; Lyons, Ronan A; Humphreys, Ioan; John, Ann; Webster, Chris; Phillips, Ceri J; Fone, David

    2017-08-15

    Neighborhood-level interventions provide an opportunity to better understand the impact of neighborhoods on health. In 2001, the Welsh Government, United Kingdom, funded Communities First, a program of neighborhood regeneration delivered to the 100 most deprived of the 881 electoral wards in Wales. In this study, we examined the association between neighborhood regeneration and mental health. Information on regeneration activities in 35 intervention areas (n = 4,197 subjects) and 75 control areas (n = 6,695 subjects) was linked to data on mental health from a cohort study with assessments made in 2001 (before regeneration) and 2008 (after regeneration). Propensity score matching was used to estimate the change in mental health in intervention neighborhoods versus control neighborhoods. Baseline differences between intervention and control areas were of similar magnitude as produced by paired randomization of neighborhoods. Regeneration was associated with an improvement in the mental health of residents in intervention areas compared with control neighborhoods (β = 1.54, 95% confidence interval: 0.50, 2.59), suggesting a reduction in socioeconomic inequalities in mental health. There was a dose-response relationship between length of residence in regeneration neighborhoods and improvements in mental health (P-trend = 0.05). These results show that targeted regeneration of deprived neighborhoods can improve mental health. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

  18. Social Capital and Economic Development: A Neighborhood Perspective

    Directory of Open Access Journals (Sweden)

    Matthew J. Hanka

    2017-12-01

    Full Text Available Sean Safford’s 2009 book Why the Garden Club Couldn’t Save Youngstown introduces a revolutionary idea that much of a community’s economic resilience is tied to the social capital that exists within it. Recent research suggests that social capital not only benefits those who develop it, but it can serve as a source of economic development in the communities in which it arises. Past quantitative research on the economic benefit of social capital has only examined the city or higher levels of aggregation. This study measures social capital in three diverse socioeconomic neighborhoods to better understand how social capital can serve as a tool for economic development. An ordered probit regression model was developed to examine how individual and neighborhood levels of social capital benefit households within these communities. Moreover, this study addresses how differences in social capital across neighborhoods are explained by both individual and neighborhood characteristics.

  19. NEIGHBORHOOD TEST DESIGN BASED ON HISTORIC PRECEDENTS

    Directory of Open Access Journals (Sweden)

    Besim S. Hakim

    2012-07-01

    Full Text Available There have been various attempts to emulate traditional architecture and to experiment with the form and aesthetics of building design. However, learning from precedents of urban morphology is rare. This design study is a test at the neighborhood level using the pattern of traditional courtyard housing that is prevalent in the majority of historic towns and cities of North Africa and the Middle East. The study is undertaken at five levels of design enquiry: dwelling types, dwelling groups, neighborhood segment and community center. All of which are synthesized into a full prototype neighborhood comprising of 428 dwelling units covering an area that includes circulation and the community center, of 17.6 hectares. The test demonstrates that the traditional pattern of neighborhoods that are based on the typology of the courtyard dwelling as the initial generator of urban form may be used to develop a contemporary settlement pattern that is compatible with current necessities of lifestyle, vehicular circulation,  including parking and infrastructure achieving an attractive livable environment with an overall gross density, that includes a community center, of about 24 dwelling units per hectare.

  20. A comparison on the propagation characteristics of focused Gaussian beam and fundamental Gaussian beam in vacuum

    International Nuclear Information System (INIS)

    Liu Shixiong; Guo Hong; Liu Mingwei; Wu Guohua

    2004-01-01

    Propagation characteristics of focused Gaussian beam (FoGB) and fundamental Gaussian beam (FuGB) propagating in vacuum are investigated. Based on the Fourier transform and the angular spectral analysis, the transverse component and the second-order approximate longitudinal component of the electric field are obtained in the paraxial approximation. The electric field components, the phase velocity and the group velocity of FoGB are compared with those of FuGB. The spot size of FoGB is also discussed

  1. Do psychosocial factors moderate the association between neighborhood walkability and adolescents' physical activity?

    Science.gov (United States)

    De Meester, Femke; Van Dyck, Delfien; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Cardon, Greet

    2013-03-01

    Ecological models emphasize the interaction between individuals and their environment. Furthermore, they posit that environmental variables influence physical activity (PA) not only directly but also indirectly through their interaction with other factors. This study explored if the association between neighborhood walkability and adolescents' PA is moderated by psychosocial factors using data from the Belgian Environmental PA Study in Youth (BEPAS-Y). BEPAS-Y recruited adolescents from 32 neighborhoods differing in objectively determined neighborhood walkability and income. Between 2008 and 2009, 637 adolescents (13-15 years; 49.4% boys) completed a survey measuring socio-demographic and psychosocial factors and wore an accelerometer for seven days. Multilevel-regression analyses revealed that for adolescents living in low-income neighborhoods, the association between neighborhood walkability and PA is moderated by perceived barriers and perceived benefits toward PA. Neighborhood walkability was positively associated with PA among adolescents, living in low-income neighborhoods, who perceived many barriers and few benefits, while for adolescents who perceived few barriers and many benefits, the PA level was high, irrespective of neighborhood walkability. For adolescents, living in high-income neighborhoods, none of the psychosocial attributes moderated the association between neighborhood walkability and PA. These findings provide some support for the predicted interactions posited by ecological models. Improving neighborhood walkability might increase PA-levels of adolescents living in low-income neighborhoods, with less positive psychosocial profiles, or in other words; those who are most difficult to reach through PA interventions. However, in order to increase PA in large populations, interventions focusing solely on improving neighborhood walkability may not have the desired effect. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Neighborhood Child Opportunity and Individual-Level Pediatric Acute Care Use and Diagnoses.

    Science.gov (United States)

    Kersten, Ellen E; Adler, Nancy E; Gottlieb, Laura; Jutte, Douglas P; Robinson, Sarah; Roundfield, Katrina; LeWinn, Kaja Z

    2018-05-01

    : media-1vid110.1542/5751513300001PEDS-VA_2017-2309 Video Abstract OBJECTIVES: Although health care providers and systems are increasingly interested in patients' nonmedical needs as a means to improve health, little is known about neighborhood conditions that contribute to child health problems. We sought to determine if a novel, publicly available measure of neighborhood context, the Child Opportunity Index, was associated with pediatric acute care visit frequency and diagnoses. This cross-sectional study included San Francisco residents <18 years of age with an emergency department and/or urgent care visit to any of 3 medical systems ( N = 47 175) between 2007 and 2011. Hot-spot analysis was used to compare the spatial distribution of neighborhood child opportunity and income. Generalized estimating equation logistic regression models were used to examine independent associations between neighborhood child opportunity and frequent acute care use (≥4 visits per year) and diagnosis group after adjusting for neighborhood income and patient age, sex, race and/or ethnicity, payer, and health system. Neighborhood child opportunity and income had distinct spatial distributions, and we identified different clusters of high- and low-risk neighborhoods. Children living in the lowest opportunity neighborhoods had significantly greater odds of ≥4 acute care visits per year (odds ratio 1.33; 95% confidence interval 1.03-1.73) compared with those in the highest opportunity neighborhoods. Neighborhood child opportunity was negatively associated with visits for respiratory conditions, asthma, assault, and ambulatory care-sensitive conditions but positively associated with injury-related visits. The Child Opportunity Index could be an effective tool for identifying neighborhood factors beyond income related to child health. Copyright © 2018 by the American Academy of Pediatrics.

  3. Calculating emittance for Gaussian and Non-Gaussian distributions by the method of correlations for slits

    International Nuclear Information System (INIS)

    Tan, Cheng-Yang; Fermilab

    2006-01-01

    One common way for measuring the emittance of an electron beam is with the slits method. The usual approach for analyzing the data is to calculate an emittance that is a subset of the parent emittance. This paper shows an alternative way by using the method of correlations which ties the parameters derived from the beamlets to the actual parameters of the parent emittance. For parent distributions that are Gaussian, this method yields exact results. For non-Gaussian beam distributions, this method yields an effective emittance that can serve as a yardstick for emittance comparisons

  4. Neighborhood Environmental Health and Premature Death From Cardiovascular Disease

    Science.gov (United States)

    Xu, Junjun; Rollins, Latrice; Baltrus, Peter; O’Connell, Laura Kathryn; Cooper, Dexter L.; Hopkins, Jammie; Botchwey, Nisha D.; Akintobi, Tabia Henry

    2018-01-01

    Introduction Cardiovascular disease (CVD) is the leading cause of death in the United States and disproportionately affects racial/ethnic minority groups. Healthy neighborhood conditions are associated with increased uptake of health behaviors that reduce CVD risk, but minority neighborhoods often have poor food access and poor walkability. This study tested the community-driven hypothesis that poor access to food at the neighborhood level and poor neighborhood walkability are associated with racial disparities in premature deaths from CVD. Methods We examined the relationship between neighborhood-level food access and walkability on premature CVD mortality rates at the census tract level for the city of Atlanta using multivariable logistic regression models. We produced maps to illustrate premature CVD mortality, food access, and walkability by census tract for the city. Results We found significant racial differences in premature CVD mortality rates and geographic disparities in food access and walkability among census tracts in Atlanta. Improved food access and walkability were associated with reduced overall premature CVD mortality in unadjusted models, but this association did not persist in models adjusted for census tract population composition and poverty. Census tracts with high concentrations of minority populations had higher levels of poor food access, poor walkability, and premature CVD mortality. Conclusion This study highlights disparities in premature CVD mortality and neighborhood food access and walkability at the census tract level in the city of Atlanta. Improving food access may have differential effects for subpopulations living in the same area. These results can be used to calibrate neighborhood-level interventions, and they highlight the need to examine race-specific health outcomes. PMID:29389312

  5. Non-Gaussianity in a quasiclassical electronic circuit

    Science.gov (United States)

    Suzuki, Takafumi J.; Hayakawa, Hisao

    2017-05-01

    We study the non-Gaussian dynamics of a quasiclassical electronic circuit coupled to a mesoscopic conductor. Non-Gaussian noise accompanying the nonequilibrium transport through the conductor significantly modifies the stationary probability density function (PDF) of the flux in the dissipative circuit. We incorporate weak quantum fluctuation of the dissipative LC circuit with a stochastic method and evaluate the quantum correction of the stationary PDF. Furthermore, an inverse formula to infer the statistical properties of the non-Gaussian noise from the stationary PDF is derived in the classical-quantum crossover regime. The quantum correction is indispensable to correctly estimate the microscopic transfer events in the QPC with the quasiclassical inverse formula.

  6. A fast Gaussian filtering algorithm for three-dimensional surface roughness measurements

    International Nuclear Information System (INIS)

    Yuan, Y B; Piao, W Y; Xu, J B

    2007-01-01

    The two-dimensional (2-D) Gaussian filter can be separated into two one-dimensional (1-D) Gaussian filters. The 1-D Gaussian filter can be implemented approximately by the cascaded Butterworth filters. The approximation accuracy will be improved with the increase of the number of the cascaded filters. A recursive algorithm for Gaussian filtering requires a relatively small number of simple mathematical operations such as addition, subtraction, multiplication, or division, so that it has considerable computational efficiency and it is very useful for three-dimensional (3-D) surface roughness measurements. The zero-phase-filtering technique is used in this algorithm, so there is no phase distortion in the Gaussian filtered mean surface. High-order approximation Gaussian filters are proposed for practical use to assure high accuracy of Gaussian filtering of 3-D surface roughness measurements

  7. A fast Gaussian filtering algorithm for three-dimensional surface roughness measurements

    Science.gov (United States)

    Yuan, Y. B.; Piao, W. Y.; Xu, J. B.

    2007-07-01

    The two-dimensional (2-D) Gaussian filter can be separated into two one-dimensional (1-D) Gaussian filters. The 1-D Gaussian filter can be implemented approximately by the cascaded Butterworth filters. The approximation accuracy will be improved with the increase of the number of the cascaded filters. A recursive algorithm for Gaussian filtering requires a relatively small number of simple mathematical operations such as addition, subtraction, multiplication, or division, so that it has considerable computational efficiency and it is very useful for three-dimensional (3-D) surface roughness measurements. The zero-phase-filtering technique is used in this algorithm, so there is no phase distortion in the Gaussian filtered mean surface. High-order approximation Gaussian filters are proposed for practical use to assure high accuracy of Gaussian filtering of 3-D surface roughness measurements.

  8. Imprint of primordial non-Gaussianity on dark matter halo profiles

    Energy Technology Data Exchange (ETDEWEB)

    Dizgah, Azadeh Moradinezhad; Dodelson, Scott; Riotto, Antonio

    2013-09-01

    We study the impact of primordial non-Gaussianity on the density profile of dark matter halos by using the semi-analytical model introduced recently by Dalal {\\it et al.} which relates the peaks of the initial linear density field to the final density profile of dark matter halos. Models with primordial non-Gaussianity typically produce an initial density field that differs from that produced in Gaussian models. We use the path-integral formulation of excursion set theory to calculate the non-Gaussian corrections to the peak profile and derive the statistics of the peaks of non-Gaussian density field. In the context of the semi-analytic model for halo profiles, currently allowed values for primordial non-Gaussianity would increase the shapes of the inner dark matter profiles, but only at the sub-percent level except in the very innermost regions.

  9. On the dependence structure of Gaussian queues

    NARCIS (Netherlands)

    Es-Saghouani, A.; Mandjes, M.R.H.

    2009-01-01

    In this article we study Gaussian queues (that is, queues fed by Gaussian processes, such as fractional Brownian motion (fBm) and the integrated Ornstein-Uhlenbeck (iOU) process), with a focus on the dependence structure of the workload process. The main question is to what extent does the workload

  10. Shedding new light on Gaussian harmonic analysis

    NARCIS (Netherlands)

    Teuwen, J.J.B.

    2016-01-01

    This dissertation consists out of two rather disjoint parts. One part concerns some results on Gaussian harmonic analysis and the other on an optimization problem in optics. In the first part we study the Ornstein–Uhlenbeck process with respect to the Gaussian measure. We focus on two areas. One is

  11. One size doesn't fit all: cross-sectional associations between neighborhood walkability, crime and physical activity depends on age and sex of residents.

    Science.gov (United States)

    Richardson, Andrea S; Troxel, Wendy M; Ghosh-Dastidar, Madhumita B; Beckman, Robin; Hunter, Gerald P; DeSantis, Amy S; Colabianchi, Natalie; Dubowitz, Tamara

    2017-01-19

    Low-income African American adults are disproportionately affected by obesity and are also least likely to engage in recommended levels of physical activity (Flegal et al. JAMA 303(3):235-41, 2010; Tucker et al. Am J Prev Med 40(4):454-61, 2011). Moderate-to-vigorous physical activity (MVPA) is an important factor for weight management and control, as well as for reducing disease risk (Andersen et al. Lancet 368(9532):299-304, 2006; Boreham and Riddoch J Sports Sci 19(12):915-29, 2001; Carson et al. PLoS One 8(8):e71417, 2013). While neighborhood greenspace and walkability have been associated with increased MVPA, evidence also suggests that living in areas with high rates of crime limits MVPA. Few studies have examined to what extent the confluence of neighborhood greenspace, walkability and crime might impact MVPA in low-income African American adults nor how associations may vary by age and sex. In 2013 we collected self-reported data on demographics, functional limitations, objective measures of MVPA (accelerometry), neighborhood greenspace (geographic information system), and walkability (street audit) in 791 predominantly African-American adults (mean age 56 years) living in two United States (U.S.) low-income neighborhoods. We also acquired data from the City of Pittsburgh on all crime events within both neighborhoods. To examine cross-sectional associations of neighborhood-related variables (i.e., neighborhood greenspace, walkability and crime) with MVPA, we used zero-inflated negative binomial regression models. Additionally, we examined potential interactions by age (over 65 years) and sex on relationships between neighborhood variables and MVPA. Overall, residents engaged in very little to no MVPA regardless of where they lived. However, for women, but not men, under the age of 65 years, living in more walkable neighborhoods was associated with more time engaged in MVPA in (β = 0.55, p = 0.007) as compared to their counterparts living in less

  12. Working with neighborhood organizations to promote wildfire preparedness

    Science.gov (United States)

    Holly Johnson Shiralipour; Martha C. Monroe; Michelle Payton

    2006-01-01

    Several government agencies and other natural resource managers have instituted outreach programs to promote wildfire preparedness in wildland-urban interface (WUI) neighborhoods that complement community-wide efforts. To help these programs become more effective, research was undertaken to gain a better understanding of the role that neighbors and neighborhood...

  13. Beyond the Cross-Sectional: Neighborhood Poverty Histories and Preterm Birth

    Science.gov (United States)

    Margerison-Zilko, Claire; Jun, Jina; Marchi, Kristen; Fingar, Kathryn; Braveman, Paula

    2015-01-01

    Objectives. We examined associations between longitudinal neighborhood poverty trajectories and preterm birth (PTB). Methods. Using data from the Neighborhood Change Database (1970–2000) and the American Community Survey (2005–2009), we categorized longitudinal trajectories of poverty for California neighborhoods (i.e., census tracts). Birth data included 23 291 singleton California births from the Maternal and Infant Health Assessment (2003–2009). We estimated associations (adjusted for individual-level covariates) between PTB and longitudinal poverty trajectories and compared these to associations using traditional, cross-sectional measures of poverty. Results. Compared to neighborhoods with long-term low poverty, those with long-term high poverty and those that experienced increasing poverty early in the study period had 41% and 37% increased odds of PTB (95% confidence interval [CI] = 1.18, 1.69 and 1.09, 1.72, respectively). High (compared with low) cross-sectional neighborhood poverty was not associated with PTB (odds ratio = 1.08; 95% CI = 0.91, 1.28). Conclusions. Neighborhood poverty histories may contribute to an understanding of perinatal health and should be considered in future research. PMID:25880941

  14. A Streaming Distance Transform Algorithm for Neighborhood-Sequence Distances

    Directory of Open Access Journals (Sweden)

    Nicolas Normand

    2014-09-01

    Full Text Available We describe an algorithm that computes a “translated” 2D Neighborhood-Sequence Distance Transform (DT using a look up table approach. It requires a single raster scan of the input image and produces one line of output for every line of input. The neighborhood sequence is specified either by providing one period of some integer periodic sequence or by providing the rate of appearance of neighborhoods. The full algorithm optionally derives the regular (centered DT from the “translated” DT, providing the result image on-the-fly, with a minimal delay, before the input image is fully processed. Its efficiency can benefit all applications that use neighborhood- sequence distances, particularly when pipelined processing architectures are involved, or when the size of objects in the source image is limited.

  15. Race, Neighborhood Economic Status, Income Inequality and Mortality.

    Science.gov (United States)

    Mode, Nicolle A; Evans, Michele K; Zonderman, Alan B

    2016-01-01

    Mortality rates in the United States vary based on race, individual economic status and neighborhood. Correlations among these variables in most urban areas have limited what conclusions can be drawn from existing research. Our study employs a unique factorial design of race, sex, age and individual poverty status, measuring time to death as an objective measure of health, and including both neighborhood economic status and income inequality for a sample of middle-aged urban-dwelling adults (N = 3675). At enrollment, African American and White participants lived in 46 unique census tracts in Baltimore, Maryland, which varied in neighborhood economic status and degree of income inequality. A Cox regression model for 9-year mortality identified a three-way interaction among sex, race and individual poverty status (p = 0.03), with African American men living below poverty having the highest mortality. Neighborhood economic status, whether measured by a composite index or simply median household income, was negatively associated with overall mortality (pinequality was associated with mortality through an interaction with individual poverty status (p = 0.04). While racial and economic disparities in mortality are well known, this study suggests that several social conditions associated with health may unequally affect African American men in poverty in the United States. Beyond these individual factors are the influences of neighborhood economic status and income inequality, which may be affected by a history of residential segregation. The significant association of neighborhood economic status and income inequality with mortality beyond the synergistic combination of sex, race and individual poverty status suggests the long-term importance of small area influence on overall mortality.

  16. Representation of Gaussian semimartingales with applications to the covariance function

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas

    2010-01-01

    stationary Gaussian semimartingales and their canonical decomposition. Thirdly, we give a new characterization of the covariance function of Gaussian semimartingales, which enable us to characterize the class of martingales and the processes of bounded variation among the Gaussian semimartingales. We...

  17. The influence of neighborhood socioeconomic status and walkability on TV viewing time.

    Science.gov (United States)

    Coogan, Patricia F; White, Laura F; Evans, Stephen R; Palmer, Julie R; Rosenberg, Lynn

    2012-11-01

    Influences on TV viewing time, which is associated with adverse health outcomes such as obesity and diabetes, need clarification. We assessed the relation of neighborhood socioeconomic status (SES) and walkability with TV viewing time in the Black Women's Health Study, a prospective study of African American women. We created neighborhood SES and walkability scores using data from the U.S. census and other sources. We estimated odds ratios for TV viewing 5+ hours/day compared with 0-1 hours/day for quintiles of neighborhood SES and walkability scores. Neighborhood SES was inversely associated with TV viewing time. The odds ratio for watching 5+ hours/day in the highest compared with the lowest quintile of neighborhood SES was 0.66 (95% CI 0.54-0.81). Neighborhood walkability was not associated with TV viewing time. Neighborhood SES should be considered in devising strategies to combat the high levels of sedentariness prevalent in African American women.

  18. The influencing factors on place attachment in neighborhood of Kampung Melayu

    Science.gov (United States)

    Lestari, W. M.; Sumabrata, J.

    2018-03-01

    Place attachment on neighborhood differs according to place characteristics and person characteristics. By dividing the research area of Kelurahan Kampung Melayu into flood area and non-flood area, this research aims at analyzing place attachment on neighborhood and analyzing factors influencing the place attachment. This research using quantitative approach using Structural Equation Modeling (SEM). Self-administered questionnaires using likert scale were distributed randomly to 400 residents. Result of the research shows that residents tend to have place attachment to their neighborhood. Factors influencing place attachment on residents born in the neighborhood with length of stay 10 years or longer and having house are family factor for residents living in non-flood area and physical factor as well as social factor for residents in flood area. This research concludes that place attachment on neighborhood is formed because dimension of place is interpreted not merely physically but also socially, namely the existence of family ties and social relationship with people in the neighborhood.

  19. Association between neighborhood need and spatial access to food stores and fast food restaurants in neighborhoods of Colonias

    OpenAIRE

    Sharkey, Joseph R; Horel, Scott; Han, Daikwon; Huber, John C

    2009-01-01

    Abstract Objective To determine the extent to which neighborhood needs (socioeconomic deprivation and vehicle availability) are associated with two criteria of food environment access: 1) distance to the nearest food store and fast food restaurant and 2) coverage (number) of food stores and fast food restaurants within a specified network distance of neighborhood areas of colonias, using ground-truthed methods. Methods Data included locational points for 315 food stores and 204 fast food rest...

  20. Parental Perceptions of Neighborhood Effects in Latino Comunas

    Science.gov (United States)

    Horner, Pilar; Sanchez, Ninive; Castillo, Marcela; Delva, Jorge

    2011-01-01

    Objectives To obtain rich information about how adult Latinos living in high-poverty/high-drug use neighborhoods perceive and negotiate their environment. Methods In 2008, thirteen adult caregivers in Santiago, Chile were interviewed with open-ended questions to ascertain beliefs about neighborhood effects and drug use. Analysis Inductive analysis was used to develop the codebook/identify trends. Discussion Residents externalized their understanding of drug use and misuse by invoking the concept of delinquent youth. A typology of their perceptions is offered. Learning more about residents’ circumstances may help focus on needs-based interventions. More research with Latino neighborhoods is needed for culturally-competent models of interventions. PMID:22497879

  1. From Neurons to Neighborhoods: An Update--Workshop Summary

    Science.gov (United States)

    Olson, Steve

    2012-01-01

    "From Neurons to Neighborhoods: An Update: Workshop Summary" is based on the original study "From Neurons to Neighborhoods: Early Childhood Development," which was released in October of 2000. From the time of the original publication's release, much has occurred to cause a fundamental reexamination of the nation's…

  2. Interaction between parenting and neighborhood quality on the risk of adolescent regular smoking.

    Science.gov (United States)

    Wen, Xiaozhong; Shenassa, Edmond D

    2012-03-01

    To conduct the first study to examine potential interaction between parenting style and neighborhood quality on the risk of adolescent regular smoking. We analyzed data from a nationally representative sample of U.S. adolescents (n = 1,213 pairs of adolescents and their parents) who participated in the Panel Study of Income Dynamics during 2002-2003. Regular smoking behavior and parental monitoring level were reported by adolescents. Parenting style (i.e., authoritative, authoritarian, permissive, and uninvolved) was defined by cross-classifying self-reported parental warmth and control. Based on parents' perceived neighborhood quality regarding raising children, neighborhoods were identified as either higher quality or lower quality. Adolescents in lower-quality neighborhoods were more likely to be regular smokers (13.7% vs. 8.5%; adjusted odds ratio [AOR] = 1.93, 95% CI = 1.02-3.65) than those in higher-quality neighborhoods. In lower-quality neighborhoods, adolescents of authoritarian parents (16.9%; AOR = 10.97, 95% CI = 3.36-35.84) were more likely and those of uninvolved parents (20.3%; AOR = 3.47, 95% CI = 0.91-13.17) were marginally more likely to be regular smokers than those of authoritative parents (4.3%). However, among adolescents in higher-quality neighborhoods, parenting style was independent of the risk of regular smoking. There was marginally significant interaction between authoritarian parenting style and neighborhood quality. Parental monitoring was associated with reduced risk of adolescent smoking, regardless of neighborhood quality. There was no interaction between parental monitoring and neighborhood quality. Authoritative parenting is associated with reduced risk of adolescent regular smoking in lower-quality neighborhoods but not in higher-quality neighborhoods. Authoritative parenting style and parental monitoring may buffer adverse influences of low-quality neighborhood.

  3. Scaled unscented transform Gaussian sum filter: Theory and application

    KAUST Repository

    Luo, Xiaodong

    2010-05-01

    In this work we consider the state estimation problem in nonlinear/non-Gaussian systems. We introduce a framework, called the scaled unscented transform Gaussian sum filter (SUT-GSF), which combines two ideas: the scaled unscented Kalman filter (SUKF) based on the concept of scaled unscented transform (SUT) (Julier and Uhlmann (2004) [16]), and the Gaussian mixture model (GMM). The SUT is used to approximate the mean and covariance of a Gaussian random variable which is transformed by a nonlinear function, while the GMM is adopted to approximate the probability density function (pdf) of a random variable through a set of Gaussian distributions. With these two tools, a framework can be set up to assimilate nonlinear systems in a recursive way. Within this framework, one can treat a nonlinear stochastic system as a mixture model of a set of sub-systems, each of which takes the form of a nonlinear system driven by a known Gaussian random process. Then, for each sub-system, one applies the SUKF to estimate the mean and covariance of the underlying Gaussian random variable transformed by the nonlinear governing equations of the sub-system. Incorporating the estimations of the sub-systems into the GMM gives an explicit (approximate) form of the pdf, which can be regarded as a "complete" solution to the state estimation problem, as all of the statistical information of interest can be obtained from the explicit form of the pdf (Arulampalam et al. (2002) [7]). In applications, a potential problem of a Gaussian sum filter is that the number of Gaussian distributions may increase very rapidly. To this end, we also propose an auxiliary algorithm to conduct pdf re-approximation so that the number of Gaussian distributions can be reduced. With the auxiliary algorithm, in principle the SUT-GSF can achieve almost the same computational speed as the SUKF if the SUT-GSF is implemented in parallel. As an example, we will use the SUT-GSF to assimilate a 40-dimensional system due to

  4. Good and Bad Neighborhood Approximations for Outlier Detection Ensembles

    DEFF Research Database (Denmark)

    Kirner, Evelyn; Schubert, Erich; Zimek, Arthur

    2017-01-01

    Outlier detection methods have used approximate neighborhoods in filter-refinement approaches. Outlier detection ensembles have used artificially obfuscated neighborhoods to achieve diverse ensemble members. Here we argue that outlier detection models could be based on approximate neighborhoods...... in the first place, thus gaining in both efficiency and effectiveness. It depends, however, on the type of approximation, as only some seem beneficial for the task of outlier detection, while no (large) benefit can be seen for others. In particular, we argue that space-filling curves are beneficial...

  5. Visible and NIR image fusion using weight-map-guided Laplacian ...

    Indian Academy of Sciences (India)

    Ashish V Vanmali

    fusion perspective, instead of the conventional haze imaging model. The proposed ... Image dehazing; Laplacian–Gaussian pyramid; multi-resolution fusion; visible–NIR image fusion; weight map. 1. .... Tan's [8] work is based on two assumptions: first, images ... responding colour image, since NIR can penetrate through.

  6. Walk Score(TM), Perceived Neighborhood Walkability, and walking in the US.

    Science.gov (United States)

    Tuckel, Peter; Milczarski, William

    2015-03-01

    To investigate both the Walk Score(TM) and a self-reported measure of neighborhood walkability ("Perceived Neighborhood Walkability") as estimators of transport and recreational walking among Americans. The study is based upon a survey of a nationally-representative sample of 1224 American adults. The survey gauged walking for both transport and recreation and included a self-reported measure of neighborhood walkability and each respondent's Walk Score(TM). Binary logistic and linear regression analyses were performed on the data. The Walk Score(TM) is associated with walking for transport, but not recreational walking nor total walking. Perceived Neighborhood Walkability is associated with transport, recreational and total walking. Perceived Neighborhood Walkability captures the experiential nature of walking more than the Walk Score(TM).

  7. Examining the social porosity of environmental features on neighborhood sociability and attachment.

    Directory of Open Access Journals (Sweden)

    John R Hipp

    Full Text Available The local neighborhood forms an integral part of our lives. It provides the context through which social networks are nurtured and the foundation from which a sense of attachment and cohesion with fellow residents can be established. Whereas much of the previous research has examined the role of social and demographic characteristic in relation to the level of neighboring and cohesion, this paper explores whether particular environmental features in the neighborhood affect social porosity. We define social porosity as the degree to which social ties flow over the surface of a neighborhood. The focus of our paper is to examine the extent to which a neighborhood's environmental features impede the level of social porosity present among residents. To do this, we integrate data from the census, topographic databases and a 2010 survey of 4,351 residents from 146 neighborhoods in Australia. The study introduces the concepts of wedges and social holes. The presence of two sources of wedges is measured: rivers and highways. The presence of two sources of social holes is measured: parks and industrial areas. Borrowing from the geography literature, several measures are constructed to capture how these features collectively carve up the physical environment of neighborhoods. We then consider how this influences residents' neighboring behavior, their level of attachment to the neighborhood and their sense of neighborhood cohesion. We find that the distance of a neighborhood to one form of social hole-industrial areas-has a particularly strong negative effect on all three dependent variables. The presence of the other form of social hole-parks-has a weaker negative effect. Neighborhood wedges also impact social interaction. Both the length of a river and the number of highway fragments in a neighborhood has a consistent negative effect on neighboring, attachment and cohesion.

  8. Efficiency of the human observer for detecting a Gaussian signal at a known location in non-Gaussian distributed lumpy backgrounds.

    Science.gov (United States)

    Park, Subok; Gallas, Bradon D; Badano, Aldo; Petrick, Nicholas A; Myers, Kyle J

    2007-04-01

    A previous study [J. Opt. Soc. Am. A22, 3 (2005)] has shown that human efficiency for detecting a Gaussian signal at a known location in non-Gaussian distributed lumpy backgrounds is approximately 4%. This human efficiency is much less than the reported 40% efficiency that has been documented for Gaussian-distributed lumpy backgrounds [J. Opt. Soc. Am. A16, 694 (1999) and J. Opt. Soc. Am. A18, 473 (2001)]. We conducted a psychophysical study with a number of changes, specifically in display-device calibration and data scaling, from the design of the aforementioned study. Human efficiency relative to the ideal observer was found again to be approximately 5%. Our variance analysis indicates that neither scaling nor display made a statistically significant difference in human performance for the task. We conclude that the non-Gaussian distributed lumpy background is a major factor in our low human-efficiency results.

  9. The role of neighborhood income inequality in adolescent aggression and violence.

    Science.gov (United States)

    Pabayo, Roman; Molnar, Beth E; Kawachi, Ichiro

    2014-10-01

    Being a perpetrator or victim of assaults can have detrimental effects on the development and health of adolescents. Area-level income inequality has been suggested to be associated with crime and aggressive behavior. However, most prior research on this association has been ecological. Therefore, the purpose of this investigation was to describe the association between neighborhood-level income inequality and aggression and violence outcomes. Data were collected from a sample of 1,878 adolescents living in 38 neighborhoods participating in the 2008 Boston Youth Survey. We used multilevel logistic regression models to estimate the association between neighborhood income inequality and attacking someone with a weapon, being attacked by someone with a weapon, being physically assaulted, being shown a gun by someone in the neighborhood, shot at by someone in the neighborhood, witnessing someone getting murdered in the past year, and having a close family member or friend murdered. Race and income inequality cross-level interactions were tested. Analyses were stratified by sex. Among nonblack boys, after adjusting for nativity, age, neighborhood-level income, crime, disorder, and proportion of the neighborhood that is black, income inequality was associated with an increased risk for committing acts of aggression and being a victim of violence. Among nonblack girls, those living in neighborhoods with high-income inequality were more likely to witness someone die a violent death in the previous year, in comparison to those in more equal neighborhoods. Income inequality appears to be related to aggression and victimization outcomes among nonblack adolescents living in Boston. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  10. McDonald's restaurants and neighborhood deprivation in Scotland and England.

    Science.gov (United States)

    Cummins, Steven C J; McKay, Laura; MacIntyre, Sally

    2005-11-01

    Features of the local fast food environment have been hypothesized to contribute to the greater prevalence of obesity in deprived neighborhoods. However, few studies have investigated whether fast food outlets are more likely to be found in poorer areas, and those that have are local case studies. In this paper, using national-level data, we examine the association between neighborhood deprivation and the density of McDonald's restaurants in small census areas (neighborhoods) in Scotland and England. Data on population, deprivation, and the location of McDonald's Restaurants were obtained for 38,987 small areas in Scotland and England (6505 "data zones" in Scotland, and 32,482 "super output areas" in England) in January 2005. Measures of McDonald's restaurants per 1000 people for each area were calculated, and areas were divided into quintiles of deprivation. Associations between neighborhood deprivation and outlet density were examined during February 2005, using one-way analysis of variance in Scotland, England, and both countries combined. Statistically significant positive associations were found between neighborhood deprivation and the mean number of McDonald's outlets per 1000 people for Scotland (p<0.001), England (p<0.001), and both countries combined (p<0.001). These associations were broadly linear with greater mean numbers of outlets per 1000 people occurring as deprivation levels increased. Observed associations between presence or absence of fast food outlets and neighborhood deprivation may provide support for environmental explanations for the higher prevalence of obesity in poor neighborhoods.

  11. Cancer mortality disparities among New York City's Upper Manhattan neighborhoods.

    Science.gov (United States)

    Hashim, Dana; Manczuk, Marta; Holcombe, Randall; Lucchini, Roberto; Boffetta, Paolo

    2017-11-01

    The East Harlem (EH), Central Harlem (CH), and Upper East Side (UES) neighborhoods of New York City are geographically contiguous to tertiary medical care, but are characterized by cancer mortality rate disparities. This ecological study aims to disentangle the effects of race and neighborhood on cancer deaths. Mortality-to-incidence ratios were determined using neighborhood-specific data from the New York State Cancer Registry and Vital Records Office (2007-2011). Ecological data on modifiable cancer risk factors from the New York City Community Health Survey (2002-2006) were stratified by sex, age group, race/ethnicity, and neighborhood and modeled against stratified mortality rates to disentangle race/ethnicity and neighborhood using logistic regression. Significant gaps in mortality rates were observed between the UES and both CH and EH across all cancers, favoring UES. Mortality-to-incidence ratios of both CH and EH were similarly elevated in the range of 0.41-0.44 compared with UES (0.26-0.30). After covariate and multivariable adjustment, black race (odds ratio=1.68; 95% confidence interval: 1.46-1.93) and EH residence (odds ratio=1.20; 95% confidence interval: 1.07-1.35) remained significant risk factors in all cancers' combined mortality. Mortality disparities remain among EH, CH, and UES neighborhoods. Both neighborhood and race are significantly associated with cancer mortality, independent of each other. Multivariable adjusted models that include Community Health Survey risk factors show that this mortality gap may be avoidable through community-based public health interventions.

  12. Neighborhood Economic Deprivation and Social Fragmentation: Associations With Children's Sleep.

    Science.gov (United States)

    Bagley, Erika J; Fuller-Rowell, Thomas E; Saini, Ekjyot K; Philbrook, Lauren E; El-Sheikh, Mona

    2016-12-09

    A growing body of work indicates that experiences of neighborhood disadvantage place children at risk for poor sleep. This study aimed to examine how both neighborhood economic deprivation (a measure of poverty) and social fragmentation (an index of instability) are associated with objective measures of the length and quality of children's sleep. Participants were 210 children (54.3% boys) living predominantly in small towns and semirural communities in Alabama. On average children were 11.3 years old (SD = .63); 66.7% of the children were European American and 33.3% were African American. The sample was socioeconomically diverse with 67.9% of the participants living at or below the poverty line and 32.1% from lower-middle-class or middle-class families. Indicators of neighborhood characteristics were derived from the 2012 American Community Survey and composited to create two variables representing neighborhood economic deprivation and social fragmentation. Child sleep period, actual sleep minutes, and efficiency were examined using actigraphy. Higher levels of neighborhood economic deprivation were associated with fewer sleep minutes and poorer sleep efficiency. More neighborhood social fragmentation was also linked with poorer sleep efficiency. Analyses controlled for demographic characteristics, child health, and family socioeconomic status. Findings indicate that living in economically and socially disadvantaged neighborhoods predicts risk for shorter and lower-quality sleep in children. Examination of community context in addition to family and individual characteristics may provide a more comprehensive understanding of the factors shaping child sleep.

  13. Helping Citizens Help Themselves : Neighborhood Improvement Programs and the Impact of Social Networks, Trust, and Norms on Neighborhood-Oriented Forms of Participation

    NARCIS (Netherlands)

    Lelieveldt, H.T.

    2004-01-01

    This article analyzes the relationship between social capital and neighborhood-oriented forms of participation within the context of an innovative Dutch neighborhood improvement program. On the basis of a survey among 307 residents, the author studies the link between three dimensions of social

  14. Limit theorems for functionals of Gaussian vectors

    Institute of Scientific and Technical Information of China (English)

    Hongshuai DAI; Guangjun SHEN; Lingtao KONG

    2017-01-01

    Operator self-similar processes,as an extension of self-similar processes,have been studied extensively.In this work,we study limit theorems for functionals of Gaussian vectors.Under some conditions,we determine that the limit of partial sums of functionals of a stationary Gaussian sequence of random vectors is an operator self-similar process.

  15. Gaussian statistics for palaeomagnetic vectors

    Science.gov (United States)

    Love, J.J.; Constable, C.G.

    2003-01-01

    With the aim of treating the statistics of palaeomagnetic directions and intensities jointly and consistently, we represent the mean and the variance of palaeomagnetic vectors, at a particular site and of a particular polarity, by a probability density function in a Cartesian three-space of orthogonal magnetic-field components consisting of a single (unimoda) non-zero mean, spherically-symmetrical (isotropic) Gaussian function. For palaeomagnetic data of mixed polarities, we consider a bimodal distribution consisting of a pair of such symmetrical Gaussian functions, with equal, but opposite, means and equal variances. For both the Gaussian and bi-Gaussian distributions, and in the spherical three-space of intensity, inclination, and declination, we obtain analytical expressions for the marginal density functions, the cumulative distributions, and the expected values and variances for each spherical coordinate (including the angle with respect to the axis of symmetry of the distributions). The mathematical expressions for the intensity and off-axis angle are closed-form and especially manageable, with the intensity distribution being Rayleigh-Rician. In the limit of small relative vectorial dispersion, the Gaussian (bi-Gaussian) directional distribution approaches a Fisher (Bingham) distribution and the intensity distribution approaches a normal distribution. In the opposite limit of large relative vectorial dispersion, the directional distributions approach a spherically-uniform distribution and the intensity distribution approaches a Maxwell distribution. We quantify biases in estimating the properties of the vector field resulting from the use of simple arithmetic averages, such as estimates of the intensity or the inclination of the mean vector, or the variances of these quantities. With the statistical framework developed here and using the maximum-likelihood method, which gives unbiased estimates in the limit of large data numbers, we demonstrate how to

  16. Gaussian statistics for palaeomagnetic vectors

    Science.gov (United States)

    Love, J. J.; Constable, C. G.

    2003-03-01

    With the aim of treating the statistics of palaeomagnetic directions and intensities jointly and consistently, we represent the mean and the variance of palaeomagnetic vectors, at a particular site and of a particular polarity, by a probability density function in a Cartesian three-space of orthogonal magnetic-field components consisting of a single (unimodal) non-zero mean, spherically-symmetrical (isotropic) Gaussian function. For palaeomagnetic data of mixed polarities, we consider a bimodal distribution consisting of a pair of such symmetrical Gaussian functions, with equal, but opposite, means and equal variances. For both the Gaussian and bi-Gaussian distributions, and in the spherical three-space of intensity, inclination, and declination, we obtain analytical expressions for the marginal density functions, the cumulative distributions, and the expected values and variances for each spherical coordinate (including the angle with respect to the axis of symmetry of the distributions). The mathematical expressions for the intensity and off-axis angle are closed-form and especially manageable, with the intensity distribution being Rayleigh-Rician. In the limit of small relative vectorial dispersion, the Gaussian (bi-Gaussian) directional distribution approaches a Fisher (Bingham) distribution and the intensity distribution approaches a normal distribution. In the opposite limit of large relative vectorial dispersion, the directional distributions approach a spherically-uniform distribution and the intensity distribution approaches a Maxwell distribution. We quantify biases in estimating the properties of the vector field resulting from the use of simple arithmetic averages, such as estimates of the intensity or the inclination of the mean vector, or the variances of these quantities. With the statistical framework developed here and using the maximum-likelihood method, which gives unbiased estimates in the limit of large data numbers, we demonstrate how to

  17. Neighborhood Frequency Effect in Chinese Word Recognition: Evidence from Naming and Lexical Decision

    Science.gov (United States)

    Li, Meng-Feng; Gao, Xin-Yu; Chou, Tai-Li; Wu, Jei-Tun

    2017-01-01

    Neighborhood frequency is a crucial variable to know the nature of word recognition. Different from alphabetic scripts, neighborhood frequency in Chinese is usually confounded by component character frequency and neighborhood size. Three experiments were designed to explore the role of the neighborhood frequency effect in Chinese and the stimuli…

  18. Subgraphs in vertex neighborhoods of K-free graphs

    DEFF Research Database (Denmark)

    Bang-Jensen, J.; Brandt, Stephan

    2004-01-01

    In a K-free graph, the neighborhood of every vertex induces a K-free subgraph. The K-free graphs with the converse property that every induced K-free subgraph is contained in the neighborhood of a vertex are characterized, based on the characterization in the case r = 3 due to Pach [8]....

  19. Consistency relations for sharp inflationary non-Gaussian features

    Energy Technology Data Exchange (ETDEWEB)

    Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Blanco Encalada 2008, Santiago (Chile); Soto, Alex, E-mail: sander.mooij@ing.uchile.cl, E-mail: gpalmaquilod@ing.uchile.cl, E-mail: gpanotop@ing.uchile.cl, E-mail: gatogeno@gmail.com [Departamento de Física, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago (Chile)

    2016-09-01

    If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming from the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.

  20. Consistency relations for sharp inflationary non-Gaussian features

    International Nuclear Information System (INIS)

    Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris; Soto, Alex

    2016-01-01

    If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming from the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.

  1. Neighborhood racial discrimination and the development of major depression.

    Science.gov (United States)

    Russell, Daniel W; Clavél, Frederick D; Cutrona, Carolyn E; Abraham, W Todd; Burzette, Rebecca G

    2018-02-01

    This study examined the impact of neighborhood racial discrimination on the development of major depressive disorder (MDD) in a sample of African American women. Participants were 499 women from Georgia and Iowa with no history of MDD who were followed for 9 to 11 years. Several neighborhood characteristics (community social disorder, community cohesion, and community racism) and individual characteristics (negative life events, financial strain, personal outlook, religious involvement, relationship quality, negative affectivity, and individual experiences of racism) were employed as predictors of whether or not the women met criteria for MDD during this period of time. In a multilevel logistic regression analysis, neighborhood-level discrimination as well as individual-level variables including the number of negative life events, financial strain, and negative affectivity were found to be significant predictors of developing MDD. Analyses of cross-level interactions indicated that the effects of neighborhood-level discrimination were moderated by the quality of individuals' relationships, such that better relationships with others served to lessen the effect of neighborhood discrimination on depression. Implications of these findings for understanding the negative effects of racial discrimination are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  2. Neighborhood, Family and Individual Influences on School Physical Victimization

    Science.gov (United States)

    Brooks-Gunn, Jeanne

    2013-01-01

    Few studies on the correlates of school violence include school and neighborhood influences. We use ecological systems theory and social disorganization theory to simultaneously incorporate neighborhood (e.g., concentrated poverty, residential instability, and immigrant concentration), school, family, and individual predictors of physical school victimization longitudinally among a large socio-economically and ethnically diverse (49% Hispanic; 34% African American) sample of 6 and 9 year olds (49% female) from the Project on Human Development in Chicago Neighborhoods (PHDCN). These children were followed up at Wave II at ages 8 and 11 (n=1425). Results of Hierarchical Generalized Linear Models reveal neighborhood residential instability increases school victimization net of family and individual correlates. Furthermore, cross-level interactions were also supported where residential family mobility has a stronger risk influence in areas of high residential instability. Also, the influence of residential family mobility is decreased in areas with higher levels of immigrant concentration. We also found cross-context connections where parent-to-child aggression in the home is connected to a higher risk of victimization at school. The role of neighborhood and family residential instability on victimization warrants further research. PMID:23263822

  3. ADOLESCENTS’ EXPOSURE TO COMMUNITY VIOLENCE: ARE NEIGHBORHOOD YOUTH ORGANIZATIONS PROTECTIVE?

    OpenAIRE

    Gardner, Margo; Brooks-Gunn, Jeanne

    2009-01-01

    Using data from the Project on Human Development in Chicago Neighborhoods (PHDCN), we identified a significant inverse association between the variety of youth organizations available at the neighborhood level and adolescents’ exposure to community violence. We examined two non-competing explanations for this finding. First, at the individual level, we tested the hypothesis that access to a greater variety of neighborhood youth organizations predicts adolescents’ participation in organized co...

  4. Neighborhood Inequalities in Adverse Pregnancy Outcomes in an Urban Setting in Spain: A Multilevel Approach

    OpenAIRE

    Garcia-Subirats, Irene; Pérez, Glòria; Rodríguez-Sanz, Maica; Muñoz, Dolores Ruiz; Salvador, Joaquín

    2012-01-01

    The aim of the present study was to describe socioeconomic inequalities in low birth weight (LBW), premature birth (PM) and small size for gestational age at birth (SGA) between 2000 and 2005 in Barcelona, Spain, jointly evaluating the effect of mother’s country of origin, and neighborhood of residence socioeconomic level measured using unemployment and educational level. We performed a cross-sectional study of births to mothers aged 12–49 years who were residents in the city of Barcelona in ...

  5. Municipality and Neighborhood Influences on Volunteering in Later Life.

    Science.gov (United States)

    Dury, Sarah; Willems, Jurgen; De Witte, Nico; De Donder, Liesbeth; Buffel, Tine; Verté, Dominique

    2016-06-01

    This article explores the relationships between municipality features and volunteering by older adults. In the literature, strong evidence exists of the influence of place on older people's health. However, the question how neighborhoods and municipalities promote or hinder volunteer participation remains under-explored. Data for the research are derived from the Belgian Aging Studies. We estimate logistic multilevel models for older individuals' engagement in volunteering across 141 municipalities in Belgium (N = 67,144). Analysis shows that neighborhood connectedness, neighborhood satisfaction, home ownership, and presence of services predict voluntary engagement at older ages. The findings support that perceptions and quality of social resources that relate to neighborhoods may be important factors to explain volunteering among older adults. Moreover, the findings suggest that volunteering in later life must be considered within a broader framework. © The Author(s) 2014.

  6. Comparing Fixed and Variable-Width Gaussian Networks

    Czech Academy of Sciences Publication Activity Database

    Kůrková, Věra; Kainen, P.C.

    2014-01-01

    Roč. 57, September (2014), s. 23-28 ISSN 0893-6080 R&D Projects: GA MŠk(CZ) LD13002 Institutional support: RVO:67985807 Keywords : Gaussian radial and kernel networks * Functionally equivalent networks * Universal approximators * Stabilizers defined by Gaussian kernels * Argminima of error functionals Subject RIV: IN - Informatics, Computer Science Impact factor: 2.708, year: 2014

  7. Quality over Quantity: Contribution of Urban Green Space to Neighborhood Satisfaction.

    Science.gov (United States)

    Zhang, Yang; Van den Berg, Agnes E; Van Dijk, Terry; Weitkamp, Gerd

    2017-05-16

    There is increasing evidence that the quality of green space significantly contributes to neighborhood satisfaction and well-being, independent of the mere amount of green space. In this paper, we examined residents' perceptions of the quality and beneficial affordances of green space in relation to objectively assessed accessibility and usability. We used data from a survey in two neighborhoods ( N = 223) of a medium-sized city in the Netherlands, which were similar in the amount of green space and other physical and socio-demographic characteristics, but differed in the availability of accessible and usable green spaces. Results show that residents of the neighborhood with a higher availability of accessible and usable green spaces were more satisfied with their neighborhood. This difference was statistically mediated by the higher level of perceived green space quality. Neighborhood satisfaction was significantly positively related to well-being. However, residents of the two neighborhoods did not differ in self-reported well-being and beneficial affordances of green space. These analyses contribute to a further understanding of how the accessibility and usability of green spaces may increase people's neighborhood satisfaction. It highlights the importance of perceived quality in addition to the amount of green space when examining the beneficial effects of green space.

  8. Neighborhood Characteristics and Disability in Older Adults

    Science.gov (United States)

    Blaney, Shannon; Cerda, Magda; Frye, Victoria; Lovasi, Gina S.; Ompad, Danielle; Rundle, Andrew; Vlahov, David

    2009-01-01

    Objective To characterize the influence of the residential neighborhood of older adults on the prevalence of disability. Methods We combined Census data on disability in older adults living in New York City with environmental information from a comprehensive geospatial database. We used factor analysis to derive dimensions of compositional and physical neighborhood characteristics and linear regression to model their association with levels of disability. Measures of neighborhood collective efficacy were added to these models to explore the impact of the social environment. Results Low neighborhood socioeconomic status, residential instability, living in areas with low proportions of foreign born and high proportions of Black residents, and negative street characteristics were associated with higher prevalence of both “physical” disability and “going outside the home” disability. High crime levels were additionally associated with physical disability, although this relationship disappeared when misdemeanor arrests were removed from the crime variable. Low levels of collective efficacy were associated with more going-outside-the-home disability, with racial/ethnic composition dropping out of this model to be replaced by an interaction term. Conclusion The urban environment may have a substantial impact on whether an older adult with a given level of functional impairment is able to age actively and remain independent. PMID:19181694

  9. Aging in Place in Gentrifying Neighborhoods: Implications for Physical and Mental Health.

    Science.gov (United States)

    Smith, Richard J; Lehning, Amanda J; Kim, Kyeongmo

    2018-01-18

    In the United States, the older adult population and the proportion of neighborhoods experiencing gentrification are both growing. However, there is limited scholarship on the effects of gentrification on older adults, with most work focusing on those who leave rather than stay. This study examines the effects of remaining in a gentrifying neighborhood on older adults' self-rated health and mental health, with particular attention to outcomes for those who are economically vulnerable. Data are from 6,810 community-dwelling respondents in metropolitan areas from the first wave of the National Health & Aging Trends Study combined with the 1970-2010 National Neighborhood Change Database. We estimate the effects of gentrification on self-rated health and mental health separately using a quasi-experimental approach and comparing two methods: matching design and linear regression. Economically vulnerable older adults in gentrifying neighborhoods reported higher self-rated health than economically vulnerable older adults in low-income neighborhoods. Both economically vulnerable and higher-income older adults in gentrifying neighborhoods had more depression and anxiety symptoms than those living in more affluent areas. Higher-income older adults in gentrifying neighborhoods had poorer mental health than their counterparts in low-income neighborhoods. Findings call attention to the complexity of gentrification, and the need for more research examining how the intersection of neighborhood and individual characteristics influences older adults' health. Results reinforce the need for neighborhood-level interventions as well as relocation support to promote health in later life and caution against an overemphasis on aging in place. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Health, Safety and Environment (HSE assessment of neighborhoods: A case study in Tehran Municipality

    Directory of Open Access Journals (Sweden)

    Narmin Hassanzadeh- Rangi

    2014-09-01

    Full Text Available Urbanization is growing rapidly in recent centuries. This phenomenon can cause many changes in various aspects of human life including the economy, education and public health This study was conducted to assess the Health, Safety and Environment (HSE problems in Tehran neighborhoods. A new instrument was developed based on the results of a literature review and formulated during a pilot study. Through cluster sampling, 10 neighborhoods were selected based from 374 neighborhoods of Tehran. Six observers completed observational items during the field studies. Secondary data were used to obtain non-observation characteristics. Standard descriptive statistics were used to compare the HSE characteristics in sampled neighborhoods. Furthermore, control chart was used to as a decision rule to identify specific variation among sampled neighborhoods. Niavaran neighborhood had the best HSE status (52.80%±25.03 whereas Khak Sefid neighborhood had the worst one (20.09%±27.51. Standard deviations of HSE characteristics were high in different parts of a neighborhood. Statistical analysis indicated that significant differences in HSE characteristics exist among sampled neighborhoods. HSE status was in warning situation in both rich and poor neighborhoods. Community-based interventions were suggested as health promotion programs to involve and empower people in neighborhoods.

  11. Coherent mode decomposition using mixed Wigner functions of Hermite-Gaussian beams.

    Science.gov (United States)

    Tanaka, Takashi

    2017-04-15

    A new method of coherent mode decomposition (CMD) is proposed that is based on a Wigner-function representation of Hermite-Gaussian beams. In contrast to the well-known method using the cross spectral density (CSD), it directly determines the mode functions and their weights without solving the eigenvalue problem. This facilitates the CMD of partially coherent light whose Wigner functions (and thus CSDs) are not separable, in which case the conventional CMD requires solving an eigenvalue problem with a large matrix and thus is numerically formidable. An example is shown regarding the CMD of synchrotron radiation, one of the most important applications of the proposed method.

  12. Covariance-Based Measurement Selection Criterion for Gaussian-Based Algorithms

    Directory of Open Access Journals (Sweden)

    Fernando A. Auat Cheein

    2013-01-01

    Full Text Available Process modeling by means of Gaussian-based algorithms often suffers from redundant information which usually increases the estimation computational complexity without significantly improving the estimation performance. In this article, a non-arbitrary measurement selection criterion for Gaussian-based algorithms is proposed. The measurement selection criterion is based on the determination of the most significant measurement from both an estimation convergence perspective and the covariance matrix associated with the measurement. The selection criterion is independent from the nature of the measured variable. This criterion is used in conjunction with three Gaussian-based algorithms: the EIF (Extended Information Filter, the EKF (Extended Kalman Filter and the UKF (Unscented Kalman Filter. Nevertheless, the measurement selection criterion shown herein can also be applied to other Gaussian-based algorithms. Although this work is focused on environment modeling, the results shown herein can be applied to other Gaussian-based algorithm implementations. Mathematical descriptions and implementation results that validate the proposal are also included in this work.

  13. Neighborhood deprivation and access to fast-food retailing: a national study.

    Science.gov (United States)

    Pearce, Jamie; Blakely, Tony; Witten, Karen; Bartie, Phil

    2007-05-01

    Obesogenic environments may be an important contextual explanation for the growing obesity epidemic, including its unequal social distribution. The objective of this study was to determine whether geographic access to fast-food outlets varied by neighborhood deprivation and school socioeconomic ranking, and whether any such associations differed to those for access to healthier food outlets. Data were collected on the location of fast-food outlets, supermarkets, and convenience stores across New Zealand. The data were geocoded and geographic information systems used to calculate travel distances from each census meshblock (i.e., neighborhood), and each school, to the closest fast-food outlet. Median travel distances are reported by a census-based index of socioeconomic deprivation for each neighborhood, and by a Ministry of Education measure of socioeconomic circumstances for each school. Analyses were repeated for outlets selling healthy food to allow comparisons. At the national level, statistically significant negative associations were found between neighborhood access to the nearest fast-food outlet and neighborhood deprivation (p<0.001) for both multinational fast-food outlets and locally operated outlets. The travel distances to both types of fast food outlet were at least twice as far in the least socially deprived neighborhoods compared to the most deprived neighborhoods. A similar pattern was found for outlets selling healthy food such as supermarkets and smaller food outlets (p<0.001). These relationships were broadly linear with travel distances tending to be shorter in more-deprived neighborhoods. There is a strong association between neighborhood deprivation and geographic access to fast food outlets in New Zealand, which may contribute to the understanding of environmental causes of obesity. However, outlets potentially selling healthy food (e.g., supermarkets) are patterned by deprivation in a similar way. These findings highlight the importance of

  14. The temporal stability of children's neighborhood experiences: A follow-up from birth to age 15

    Directory of Open Access Journals (Sweden)

    Tom Kleinepier

    2017-06-01

    Full Text Available Background: Despite increasing attention being paid to the temporal dynamics of childhood disadvantage, children's neighborhood characteristics are still frequently measured at a single point in time. Whether such cross-sectional measures serve as reliable proxies for children's long-run neighborhood conditions depends on the stability in children's neighborhood experiences over time. Objective: We investigate stability in children's neighborhood environment over time, focusing on two of the most commonly studied neighborhood socioeconomic conditions: The ethnic composition and mean income of the neighborhood. Methods: Drawing on data from the Dutch population registers, an entire cohort of children born in the Netherlands in 1999 (n=179,166 is followed from birth up until age 15. We use year-to-year correlations in the percentage of non-Western ethnic minorities and the mean logged income in the neighborhood to evaluate the temporal stability of children's neighborhood experiences. Results: Results indicate that children's neighborhood characteristics are more stable over time with regard to ethnic composition than with regard to the mean income. Children who had moved at least once had less stability in neighborhood characteristics than children who never moved. Finally, neighborhood experiences were found to be more stable over time for ethnic minority children, although differences were small with regard to mean income in the neighborhood. Conclusions: We conclude that single point-in-time measurements of neighborhood characteristics are reasonable proxies for the long-run ethnic composition of children's neighborhood environment, but rather noisy proxies for the long-run income status of their neighborhood, particularly for those who moved. Contribution: We examine the temporal stability of children's neighborhood experiences over almost the entire childhood life course in the European context.

  15. The bias of weighted dark matter halos from peak theory

    CERN Document Server

    Verde, Licia; Simpson, Fergus; Alvarez-Gaume, Luis; Heavens, Alan; Matarrese, Sabino

    2014-01-01

    We give an analytical form for the weighted correlation function of peaks in a Gaussian random field. In a cosmological context, this approach strictly describes the formation bias and is the main result here. Nevertheless, we show its validity and applicability to the evolved cosmological density field and halo field, using Gaussian random field realisations and dark matter N-body numerical simulations. Using this result from peak theory we compute the bias of peaks (and dark matter halos) and show that it reproduces results from the simulations at the ${\\mathcal O}(10\\%)$ level. Our analytical formula for the bias predicts a scale-dependent bias with two characteristics: a broad band shape which, however, is most affected by the choice of weighting scheme and evolution bias, and a more robust, narrow feature localised at the BAO scale, an effect that is confirmed in simulations. This scale-dependent bias smooths the BAO feature but, conveniently, does not move it. We provide a simple analytic formula to des...

  16. Impact of neighborhood separation on the spatial reciprocity in the prisoner’s dilemma game

    International Nuclear Information System (INIS)

    Xia, Chengyi; Miao, Qin; Zhang, Juanjuan

    2013-01-01

    Highlights: • We present a novel game model in which interaction and learning neighborhood is not identical. • The separation between interaction and learning neighborhood can largely influence the cooperative behaviors. • Monte Carlo simulations are utilized to verify the evolution of cooperation. • When IN is fixed to be 4, medium-sized LN = 8 is the optimal size to promote the cooperation. • When LN is fixed to be 4, the cooperation can also be highly enhanced when IN > 4. -- Abstract: The evolutionary game theory is a very powerful tool to understand the collective cooperation behavior in many real-world systems. In the spatial game model, the payoff is often first obtained within a specific neighborhood (i.e., interaction neighborhood) and then the focal player imitates or learns the behavior of a randomly selected one inside another neighborhood which is named after the learning neighborhood. However, most studies often assume that the interaction neighborhood is identical with the learning neighborhood. Beyond this assumption, we present a spatial prisoner’s dilemma game model to discuss the impact of separation between interaction neighborhood and learning neighborhood on the cooperative behaviors among players on the square lattice. Extensive numerical simulations demonstrate that separating the interaction neighborhood from the learning neighborhood can dramatically affect the density of cooperators (ρ C ) in the population at the stationary state. In particular, compared to the standard case, we find that the medium-sized learning (interaction) neighborhood allows the cooperators to thrive and substantially favors the evolution of cooperation and ρ C can be greatly elevated when the interaction (learning) neighborhood is fixed, that is, too little or much information is not beneficial for players to make the contributions for the collective cooperation. Current results are conducive to further analyzing and understanding the emergence of

  17. A Neighborhood Story

    Science.gov (United States)

    Gerrish, Michael

    2009-01-01

    Blue collar doesn't have to mean drab and dull. At least, not to Troy, New York, historian Mike Esposito, who is a member of a neighborhood revitalization movement seeking to celebrate the people and events that brought diversity, prosperity, and vitality to this upstate New York community more than 100 years ago. Esposito and others invited…

  18. Loss of Trust in the Neighborhood: The Experience of Older African Americans in Detroit.

    Science.gov (United States)

    Fritz, Heather; Cutchin, Malcolm P; Cummins, Emily R

    2018-02-19

    Although evidence suggests that neighborhood conditions are related to stress and health, the processes connecting neighborhood conditions and stress for older minorities is little explored. The purpose of this analysis is to contribute new insights into this issue. We conducted a qualitative analysis as part of a larger mixed methods study of 100 African Americans aged 55 and older living in neighborhoods of varying quality in Detroit, Michigan. A subsample of (n = 20) older adults took photographs of bothersome aspects of their neighborhoods and participated in in-depth photo-elicitation interviews. Data were analyzed using a grounded theory approach. 'Loss of trust in the neighborhood' emerged as the core category to explain how older African Americans in our sample experienced neighborhood stressors in their daily lives. Loss of trust in physical, social, and institutional dimensions of the neighborhood contributed to the core category. The life course of neighborhoods and the trust placed in them appears to be intimately connected to the well-being of older African Americans. We therefore hypothesize that a fundamental pathway through which neighborhood stressors are experienced for older African Americans in U.S. 'Rust Belt' cities is the multifaceted loss of trust in the neighborhood.

  19. Perceived neighborhood characteristics predict severity and emotional response to daily stressors.

    Science.gov (United States)

    Scott, Stacey B; Munoz, Elizabeth; Mogle, Jacqueline A; Gamaldo, Alyssa A; Smyth, Joshua M; Almeida, David M; Sliwinski, Martin J

    2018-03-01

    Neighborhood characteristics may influence health and well-being outcomes through stressors in daily life. This study tested whether a varied set of perceived characteristics of neighborhood (i.e., social cohesion, safety, aesthetic quality, violence) predicted stressor frequency and severity as well as negative emotional responses to stressors. We predicted greater reported cohesion and safety and less violence would be associated with less frequent stressor exposure and severity and less intense negative affect following stressors; we conducted subsequent tests of neighborhood aesthetic quality as a predictor. Participants (n = 233, age 25-65 years) were residents in a socio-economically, racially, and ethnically diverse zip code in Bronx, New York, most who participated in the Effects of Stress on Cognitive Aging, Physiology and Emotion study between 2012 and 2013. They provided demographic information and neighborhood ratings, then participated in the EMA protocol in which they completed brief smartphone surveys of current negative affect and stressor exposure, severity, and recency, five times daily for 14 days. No coded neighborhood characteristic was related to the frequency of stressors. Individuals who reported greater neighborhood violence, however, rated their stressors as more severe. Individuals rating their neighborhood lower in safety or aesthetic quality, or higher in violence, had greater negative affect following stressors. Even among people living within the same zip code, individual differences in perceptions of neighborhood predict how stressful they appraised stressors in daily life to be and how much negative affect they reported following stressors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Gaussian Process-Mixture Conditional Heteroscedasticity.

    Science.gov (United States)

    Platanios, Emmanouil A; Chatzis, Sotirios P

    2014-05-01

    Generalized autoregressive conditional heteroscedasticity (GARCH) models have long been considered as one of the most successful families of approaches for volatility modeling in financial return series. In this paper, we propose an alternative approach based on methodologies widely used in the field of statistical machine learning. Specifically, we propose a novel nonparametric Bayesian mixture of Gaussian process regression models, each component of which models the noise variance process that contaminates the observed data as a separate latent Gaussian process driven by the observed data. This way, we essentially obtain a Gaussian process-mixture conditional heteroscedasticity (GPMCH) model for volatility modeling in financial return series. We impose a nonparametric prior with power-law nature over the distribution of the model mixture components, namely the Pitman-Yor process prior, to allow for better capturing modeled data distributions with heavy tails and skewness. Finally, we provide a copula-based approach for obtaining a predictive posterior for the covariances over the asset returns modeled by means of a postulated GPMCH model. We evaluate the efficacy of our approach in a number of benchmark scenarios, and compare its performance to state-of-the-art methodologies.

  1. ECG Denoising Using Marginalized Particle Extended Kalman Filter With an Automatic Particle Weighting Strategy.

    Science.gov (United States)

    Hesar, Hamed Danandeh; Mohebbi, Maryam

    2017-05-01

    In this paper, a model-based Bayesian filtering framework called the "marginalized particle-extended Kalman filter (MP-EKF) algorithm" is proposed for electrocardiogram (ECG) denoising. This algorithm does not have the extended Kalman filter (EKF) shortcoming in handling non-Gaussian nonstationary situations because of its nonlinear framework. In addition, it has less computational complexity compared with particle filter. This filter improves ECG denoising performance by implementing marginalized particle filter framework while reducing its computational complexity using EKF framework. An automatic particle weighting strategy is also proposed here that controls the reliance of our framework to the acquired measurements. We evaluated the proposed filter on several normal ECGs selected from MIT-BIH normal sinus rhythm database. To do so, artificial white Gaussian and colored noises as well as nonstationary real muscle artifact (MA) noise over a range of low SNRs from 10 to -5 dB were added to these normal ECG segments. The benchmark methods were the EKF and extended Kalman smoother (EKS) algorithms which are the first model-based Bayesian algorithms introduced in the field of ECG denoising. From SNR viewpoint, the experiments showed that in the presence of Gaussian white noise, the proposed framework outperforms the EKF and EKS algorithms in lower input SNRs where the measurements and state model are not reliable. Owing to its nonlinear framework and particle weighting strategy, the proposed algorithm attained better results at all input SNRs in non-Gaussian nonstationary situations (such as presence of pink noise, brown noise, and real MA). In addition, the impact of the proposed filtering method on the distortion of diagnostic features of the ECG was investigated and compared with EKF/EKS methods using an ECG diagnostic distortion measure called the "Multi-Scale Entropy Based Weighted Distortion Measure" or MSEWPRD. The results revealed that our proposed

  2. Resonant non-Gaussianity with equilateral properties

    International Nuclear Information System (INIS)

    Gwyn, Rhiannon; Rummel, Markus

    2012-11-01

    We discuss the effect of superimposing multiple sources of resonant non-Gaussianity, which arise for instance in models of axion inflation. The resulting sum of oscillating shape contributions can be used to ''Fourier synthesize'' different non-oscillating shapes in the bispectrum. As an example we reproduce an approximately equilateral shape from the superposition of O(10) oscillatory contributions with resonant shape. This implies a possible degeneracy between the equilateral-type non-Gaussianity typical of models with non-canonical kinetic terms, such as DBI inflation, and an equilateral-type shape arising from a superposition of resonant-type contributions in theories with canonical kinetic terms. The absence of oscillations in the 2-point function together with the structure of the resonant N-point functions, imply that detection of equilateral non-Gaussianity at a level greater than the PLANCK sensitivity of f NL ∝O(5) will rule out a resonant origin. We comment on the questions arising from possible embeddings of this idea in a string theory setting.

  3. Non-Gaussian conductivity fluctuations in semiconductors

    International Nuclear Information System (INIS)

    Melkonyan, S.V.

    2010-01-01

    A theoretical study is presented on the statistical properties of conductivity fluctuations caused by concentration and mobility fluctuations of the current carriers. It is established that mobility fluctuations result from random deviations in the thermal equilibrium distribution of the carriers. It is shown that mobility fluctuations have generation-recombination and shot components which do not satisfy the requirements of the central limit theorem, in contrast to the current carrier's concentration fluctuation and intraband component of the mobility fluctuation. It is shown that in general the mobility fluctuation consist of thermal (or intraband) Gaussian and non-thermal (or generation-recombination, shot, etc.) non-Gaussian components. The analyses of theoretical results and experimental data from literature show that the statistical properties of mobility fluctuation and of 1/f-noise fully coincide. The deviation from Gaussian statistics of the mobility or 1/f fluctuations goes hand in hand with the magnitude of non-thermal noise (generation-recombination, shot, burst, pulse noises, etc.).

  4. Legendre Duality of Spherical and Gaussian Spin Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Genovese, Giuseppe, E-mail: giuseppe.genovese@math.uzh.ch [Universität Zürich, Institut für Mathematik (Switzerland); Tantari, Daniele, E-mail: daniele.tantari@sns.it [Scuola Normale Superiore di Pisa, Centro Ennio de Giorgi (Italy)

    2015-12-15

    The classical result of concentration of the Gaussian measure on the sphere in the limit of large dimension induces a natural duality between Gaussian and spherical models of spin glass. We analyse the Legendre variational structure linking the free energies of these two systems, in the spirit of the equivalence of ensembles of statistical mechanics. Our analysis, combined with the previous work (Barra et al., J. Phys. A: Math. Theor. 47, 155002, 2014), shows that such models are replica symmetric. Lastly, we briefly discuss an application of our result to the study of the Gaussian Hopfield model.

  5. Legendre Duality of Spherical and Gaussian Spin Glasses

    International Nuclear Information System (INIS)

    Genovese, Giuseppe; Tantari, Daniele

    2015-01-01

    The classical result of concentration of the Gaussian measure on the sphere in the limit of large dimension induces a natural duality between Gaussian and spherical models of spin glass. We analyse the Legendre variational structure linking the free energies of these two systems, in the spirit of the equivalence of ensembles of statistical mechanics. Our analysis, combined with the previous work (Barra et al., J. Phys. A: Math. Theor. 47, 155002, 2014), shows that such models are replica symmetric. Lastly, we briefly discuss an application of our result to the study of the Gaussian Hopfield model

  6. Methods to characterize non-Gaussian noise in TAMA

    International Nuclear Information System (INIS)

    Ando, Masaki; Arai, K; Takahashi, R; Tatsumi, D; Beyersdorf, P; Kawamura, S; Miyoki, S; Mio, N; Moriwaki, S; Numata, K; Kanda, N; Aso, Y; Fujimoto, M-K; Tsubono, K; Kuroda, K

    2003-01-01

    We present a data characterization method for the main output signal of the interferometric gravitational-wave detector, in particular targeting at effective detection of burst gravitational waves from stellar core collapse. The time scale of non-Gaussian events is evaluated in this method, and events with longer time scale than real signals are rejected as non-Gaussian noises. As a result of data analysis using 1000 h of real data with the interferometric gravitational-wave detector TAMA300, the false-alarm rate was improved 10 3 times with this non-Gaussian noise evaluation and rejection method

  7. One size doesn’t fit all: cross-sectional associations between neighborhood walkability, crime and physical activity depends on age and sex of residents

    Directory of Open Access Journals (Sweden)

    Andrea S. Richardson

    2017-01-01

    Full Text Available Abstract Background Low-income African American adults are disproportionately affected by obesity and are also least likely to engage in recommended levels of physical activity (Flegal et al. JAMA 303(3:235-41, 2010; Tucker et al. Am J Prev Med 40(4:454-61, 2011. Moderate-to-vigorous physical activity (MVPA is an important factor for weight management and control, as well as for reducing disease risk (Andersen et al. Lancet 368(9532:299-304, 2006; Boreham and Riddoch J Sports Sci 19(12:915-29, 2001; Carson et al. PLoS One 8(8:e71417, 2013. While neighborhood greenspace and walkability have been associated with increased MVPA, evidence also suggests that living in areas with high rates of crime limits MVPA. Few studies have examined to what extent the confluence of neighborhood greenspace, walkability and crime might impact MVPA in low-income African American adults nor how associations may vary by age and sex. Methods In 2013 we collected self-reported data on demographics, functional limitations, objective measures of MVPA (accelerometry, neighborhood greenspace (geographic information system, and walkability (street audit in 791 predominantly African-American adults (mean age 56 years living in two United States (U.S. low-income neighborhoods. We also acquired data from the City of Pittsburgh on all crime events within both neighborhoods. Exposure: To examine cross-sectional associations of neighborhood-related variables (i.e., neighborhood greenspace, walkability and crime with MVPA, we used zero-inflated negative binomial regression models. Additionally, we examined potential interactions by age (over 65 years and sex on relationships between neighborhood variables and MVPA. Results Overall, residents engaged in very little to no MVPA regardless of where they lived. However, for women, but not men, under the age of 65 years, living in more walkable neighborhoods was associated with more time engaged in MVPA in (β = 0.55, p = 0

  8. Statistical-mechanics analysis of Gaussian labeled-unlabeled classification problems

    International Nuclear Information System (INIS)

    Tanaka, Toshiyuki

    2013-01-01

    The labeled-unlabeled classification problem in semi-supervised learning is studied via statistical-mechanics approach. We analytically investigate performance of a learner with an equal-weight mixture of two symmetrically-located Gaussians, performing posterior mean estimation of the parameter vector on the basis of a dataset consisting of labeled and unlabeled data generated from the same probability model as that assumed by the learner. Under the assumption of replica symmetry, we have analytically obtained a set of saddle-point equations, which allows us to numerically evaluate performance of the learner. On the basis of the analytical result we have observed interesting phenomena, in particular the coexistence of good and bad solutions, which may happen when the number of unlabeled data is relatively large compared with that of labeled data

  9. Perception of neighborhood crime and drugs increases cardiometabolic risk in Chilean adolescents

    Science.gov (United States)

    Martinez, Suzanna M; Blanco, Estela; Delva, Jorge; Burrows, Raquel; Reyes, Marcela; Lozoff, Betsy; Gahagan, Sheila

    2013-01-01

    Purpose Studies report an association between neighborhood risk and both obesity and cardiometabolic risk factors (CMR) among adolescents. Here we describe the effect of perceived neighborhood risk on adiposity and CMR among Chilean adolescents. Methods Participants were 523 low- to middle-income Chilean adolescents. We assessed neighborhood risk in early adolescence, adiposity in childhood and in early and later adolescence, and blood pressure and fasting glucose in later adolescence. Neighborhood risk profiles were estimated using latent profile analysis (LPA) and based on reported perceptions of crime and drug sales/use. Using linear and logistic regression, we examined the effect of neighborhood risk on adiposity and CMR. Results Mean age in early and later adolescence was 14 and 17 years, respectively. Participants were 52% male, with a mean BMI z-score of 0.67, and 8% met criteria for the metabolic syndrome. LPA identified two neighborhood profiles: 61% low risk and 39% high risk. In later adolescence, being in the high risk profile predicted a higher BMI z-score, waist-to-height ratio, and fat mass index (p-values Chilean neighborhoods with high crime and drugs, targeted public health interventions and policies for youth could be beneficial. PMID:24411818

  10. Durham Neighborhood Compass Block Groups

    Data.gov (United States)

    City and County of Durham, North Carolina — The Durham Neighborhood Compass is a quantitative indicators project with qualitative values, integrating data from local government, the Census Bureau and other...

  11. Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents.

    Science.gov (United States)

    Lenhart, Clare M; Wiemken, Andrew; Hanlon, Alexandra; Perkett, Mackenzie; Patterson, Freda

    2017-09-18

    A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students. Using cross-sectional, weighted data from the 2015 Pennsylvania (USA) State and Philadelphia city Youth Risk Behavior Survey, multivariable logistic regression modeling was used to examine the association between perceived neighborhood safety, and physical activity levels and recreational screen-based sedentary behavior time respectively, while controlling for potential confounders. After adjustment for other significant correlates of physical activity, students with low perceived neighborhood safety had a 21% reduced odds of being physically active on 5 or more days of the last week as compared to those who felt safe (p = 0.044). Perceived safety was not related to sedentary behavior; but sports team participation emerged as a strong correlate of low screen-based sedentary behavior (OR = 0.73, p = .002). These data add to a growing body of work demonstrating the importance of perceived safety with physical activity levels in youth. Sports team participation may be a viable target to reduce screen-based sedentary time.

  12. Perceived neighborhood safety related to physical activity but not recreational screen-based sedentary behavior in adolescents

    Directory of Open Access Journals (Sweden)

    Clare M. Lenhart

    2017-09-01

    Full Text Available Abstract Background A growing proportion of adolescents have poor cardiovascular health behaviors, including low levels of physical activity and high levels of sedentary behavior, thus increasing the likelihood of poor heart health in later years. This study tested the hypothesis that low perceived neighborhood safety would be associated with low levels of physical activity and high levels of recreational sedentary behavior in high-school students. Methods Using cross-sectional, weighted data from the 2015 Pennsylvania (USA State and Philadelphia city Youth Risk Behavior Survey, multivariable logistic regression modeling was used to examine the association between perceived neighborhood safety, and physical activity levels and recreational screen-based sedentary behavior time respectively, while controlling for potential confounders. Results After adjustment for other significant correlates of physical activity, students with low perceived neighborhood safety had a 21% reduced odds of being physically active on 5 or more days of the last week as compared to those who felt safe (p = 0.044. Perceived safety was not related to sedentary behavior; but sports team participation emerged as a strong correlate of low screen-based sedentary behavior (OR = 0.73, p = .002. Conclusion These data add to a growing body of work demonstrating the importance of perceived safety with physical activity levels in youth. Sports team participation may be a viable target to reduce screen-based sedentary time.

  13. Scalable Gaussian Processes and the search for exoplanets

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Gaussian Processes are a class of non-parametric models that are often used to model stochastic behavior in time series or spatial data. A major limitation for the application of these models to large datasets is the computational cost. The cost of a single evaluation of the model likelihood scales as the third power of the number of data points. In the search for transiting exoplanets, the datasets of interest have tens of thousands to millions of measurements with uneven sampling, rendering naive application of a Gaussian Process model impractical. To attack this problem, we have developed robust approximate methods for Gaussian Process regression that can be applied at this scale. I will describe the general problem of Gaussian Process regression and offer several applicable use cases. Finally, I will present our work on scaling this model to the exciting field of exoplanet discovery and introduce a well-tested open source implementation of these new methods.

  14. Neighborhood Poverty and Maternal Fears of Children's Outdoor Play

    Science.gov (United States)

    Kimbro, Rachel Tolbert; Schachter, Ariela

    2011-01-01

    Investigating children's outdoor play unites scholarship on neighborhoods, parental perceptions of safety, and children's health. Utilizing the Fragile Families and Child Well-being Study (N = 3,448), we examine mothers' fear of their 5-year-old children playing outdoors, testing associations with neighborhood social characteristics, city-level…

  15. Adolescent Physical Activity: Moderation of Individual Factors by Neighborhood Environment.

    Science.gov (United States)

    D'Angelo, Heather; Fowler, Stephanie L; Nebeling, Linda C; Oh, April Y

    2017-06-01

    Less than a third of U.S. adolescents meet federal physical activity (PA) guidelines. Understanding correlates of PA at multiple levels of the Social Ecological Model could improve PA interventions among youth. This study examines (1) associations between factors across the Social Ecological Model including psychosocial factors, perceived neighborhood physical and social environment characteristics, and adolescent moderate to vigorous PA (MVPA) and (2) whether perceived neighborhood characteristics moderate associations between psychosocial factors and MVPA. A national sample of adolescents (aged 12-17 years) in the 2014 Family Life, Activity, Sun, Health, and Eating Study was used to examine associations between psychosocial characteristics, perceived neighborhood social and physical characteristics, and self-reported weekly minutes of MVPA. Analyses were conducted in 2015. Interaction terms between psychosocial and neighborhood variables were added to multiple linear regression models to examine moderation hypotheses. Significant two-way interactions revealed that neighborhoods with features perceived as supportive of PA strengthened several psychosocial-MVPA associations. The positive associations between MVPA and friend norms, friend support, and attitudes were strengthened for adolescents living in neighborhoods with high versus low PA resource availability (all p<0.05). Furthermore, the association between controlled and autonomous motivation and MVPA was strengthened under conditions of shops/stores near (versus distant from) adolescents' homes (p<0.05). The association between some psychosocial factors and adolescent MVPA may be environment dependent. Neighborhood physical and social environments supportive of PA are important to consider when developing targeted PA interventions and may strengthen the association between psychosocial-level factors and adolescent MVPA. Copyright © 2017 American Journal of Preventive Medicine. All rights reserved.

  16. Bringing urban governance back in: Neighborhood conflicts and depression.

    Science.gov (United States)

    Fu, Qiang

    2018-01-01

    Urban governance and its impact on contentious politics have received remarkably little attention in existing studies on mental health. Drawing on a measure of neighborhood conflicts developed in a survey of thirty-nine urban neighborhoods in Guangzhou, China, this article investigates the potential link between urban governance and mental health. Net of sociodemographic, relational, and environmental measures, it finds that among residents' conflicts with different entities of urban governance, only those with local/grassroots governments are significantly associated with more depressive symptoms. Moreover, these subgroups of government-oriented conflicts associated with more depressive symptoms are related to neighborhood planning and communal properties, reflecting a dilemma in the Chinese model of urban governance. By offering a relational interpretation of neighborhood conflicts, this study not only challenges the previous view that community building in China improves mental health, but calls attention to the significance of urban governance in research on mental health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Realistic continuous-variable quantum teleportation with non-Gaussian resources

    International Nuclear Information System (INIS)

    Dell'Anno, F.; De Siena, S.; Illuminati, F.

    2010-01-01

    We present a comprehensive investigation of nonideal continuous-variable quantum teleportation implemented with entangled non-Gaussian resources. We discuss in a unified framework the main decoherence mechanisms, including imperfect Bell measurements and propagation of optical fields in lossy fibers, applying the formalism of the characteristic function. By exploiting appropriate displacement strategies, we compute analytically the success probability of teleportation for input coherent states and two classes of non-Gaussian entangled resources: two-mode squeezed Bell-like states (that include as particular cases photon-added and photon-subtracted de-Gaussified states), and two-mode squeezed catlike states. We discuss the optimization procedure on the free parameters of the non-Gaussian resources at fixed values of the squeezing and of the experimental quantities determining the inefficiencies of the nonideal protocol. It is found that non-Gaussian resources enhance significantly the efficiency of teleportation and are more robust against decoherence than the corresponding Gaussian ones. Partial information on the alphabet of input states allows further significant improvement in the performance of the nonideal teleportation protocol.

  18. Generation of Quasi-Gaussian Pulses Based on Correlation Techniques

    Directory of Open Access Journals (Sweden)

    POHOATA, S.

    2012-02-01

    Full Text Available The Gaussian pulses have been mostly used within communications, where some applications can be emphasized: mobile telephony (GSM, where GMSK signals are used, as well as the UWB communications, where short-period pulses based on Gaussian waveform are generated. Since the Gaussian function signifies a theoretical concept, which cannot be accomplished from the physical point of view, this should be expressed by using various functions, able to determine physical implementations. New techniques of generating the Gaussian pulse responses of good precision are approached, proposed and researched in this paper. The second and third order derivatives with regard to the Gaussian pulse response are accurately generated. The third order derivates is composed of four individual rectangular pulses of fixed amplitudes, being easily to be generated by standard techniques. In order to generate pulses able to satisfy the spectral mask requirements, an adequate filter is necessary to be applied. This paper emphasizes a comparative analysis based on the relative error and the energy spectra of the proposed pulses.

  19. Neighborhood differences in social capital: a compositional artifact or a contextual construct?

    Science.gov (United States)

    Subramanian, S V; Lochner, Kimberly A; Kawachi, Ichiro

    2003-03-01

    Assessment of social capital at the neighborhood level is often based on aggregating individual perceptions of trust and reciprocity. Individual perceptions, meanwhile, are influenced through a range of individual attributes. This paper examines the socioeconomic and demographic attributes that systematically correlate with individual perception of social capital and determines the extent to which such attributes account for neighborhood differences in social capital. Using improved multilevel modeling procedures, we ascertain the extent to which differences in social capital perception can be ascribed to true neighborhood-level variations. The analysis is based on the 1994-95 Community Survey of the Project on Human Development in Chicago Neighborhoods (PHDCN). The response measure is based on survey respondent's perceptions of whether people in their neighborhood can be trusted. The results suggest that even after accounting for individual demographic (age, sex, race, marital status) and socioeconomic characteristics (income, education), significant neighborhood differences remain in individual perceptions of trust, substantiating the notion of social capital as a true contextual construct.

  20. Bayes factor between Student t and Gaussian mixed models within an animal breeding context

    Directory of Open Access Journals (Sweden)

    García-Cortés Luis

    2008-07-01

    Full Text Available Abstract The implementation of Student t mixed models in animal breeding has been suggested as a useful statistical tool to effectively mute the impact of preferential treatment or other sources of outliers in field data. Nevertheless, these additional sources of variation are undeclared and we do not know whether a Student t mixed model is required or if a standard, and less parameterized, Gaussian mixed model would be sufficient to serve the intended purpose. Within this context, our aim was to develop the Bayes factor between two nested models that only differed in a bounded variable in order to easily compare a Student t and a Gaussian mixed model. It is important to highlight that the Student t density converges to a Gaussian process when degrees of freedom tend to infinity. The twomodels can then be viewed as nested models that differ in terms of degrees of freedom. The Bayes factor can be easily calculated from the output of a Markov chain Monte Carlo sampling of the complex model (Student t mixed model. The performance of this Bayes factor was tested under simulation and on a real dataset, using the deviation information criterion (DIC as the standard reference criterion. The two statistical tools showed similar trends along the parameter space, although the Bayes factor appeared to be the more conservative. There was considerable evidence favoring the Student t mixed model for data sets simulated under Student t processes with limited degrees of freedom, and moderate advantages associated with using the Gaussian mixed model when working with datasets simulated with 50 or more degrees of freedom. For the analysis of real data (weight of Pietrain pigs at six months, both the Bayes factor and DIC slightly favored the Student t mixed model, with there being a reduced incidence of outlier individuals in this population.

  1. Do Sleep and Psychological Distress Mediate the Association Between Neighborhood Factors and Pain?

    Science.gov (United States)

    Brooks Holliday, Stephanie; Dubowitz, Tamara; Ghosh-Dastidar, Bonnie; Beckman, Robin; Buysse, Daniel; Hale, Lauren; Buman, Matthew; Troxel, Wendy

    2018-05-14

    Pain affects millions of American adults. However, individuals from socioeconomically disadvantaged groups experience higher rates of pain, and individuals from racial/ethnic minorities report greater pain severity and pain-related disability. Some studies find an association between neighborhood socioeconomic status and pain. The present study aimed to further understand the association between neighborhood disadvantage and pain, including the role of objective (e.g., crime rates) and subjective neighborhood characteristics (e.g., perceived safety, neighborhood satisfaction), and to examine sleep and psychological distress as potential mediators of these associations. The sample included 820 participants from two predominantly African American socioeconomically disadvantaged neighborhoods. Trained data collectors interviewed participants on a number of self-report measures, and objective neighborhood characteristics were obtained from city crime data and street segment audits. Subjective characteristics, specifically perceived infrastructure and perceived safety, were associated with pain. Based on bootstrapped regression models, sleep efficiency and psychological distress were tested as mediators of the association between these neighborhood factors and pain. Results of mediation testing indicated that psychological distress served as a significant mediator. Though sleep efficiency was not a mediator, it had a significant independent association with pain. Understanding the contribution of sleep problems and psychological distress to pain among at-risk individuals living in disadvantaged neighborhoods is important to identifying ways that individual- and neighborhood-level interventions may be leveraged to reduce pain-related disparities.

  2. The impact of childhood neighborhood disadvantage on adult joblessness and income.

    Science.gov (United States)

    Alvarado, Steven Elías

    2018-02-01

    Research on residential inequality focuses heavily on adult economic outcomes as crucial components of the intergenerational transmission of poverty. Yet, empirical evidence on whether youth neighborhoods have a lasting impact on adult economic outcomes at the national level is scarce. Further, we know little about how youth neighborhood effects on adult economic outcomes manifest. This study uses 26 years (14 waves) of restricted panel data from the NLSY79 and the NLSY Children and Young Adults cohorts - data that have never been used to analyze long-term neighborhood effects - to examine whether youth neighborhood disadvantage impacts adult economic outcomes through sensitive years in childhood, teen socialization, duration effects, or cumulative effects. Sibling fixed effects models that net out unobserved effects of shared family characteristics suggest that youth neighborhood disadvantage increases joblessness and reduces income in adulthood. However, exposure across specific developmental stages of youth does not appear to act as a significant moderator while sustained exposure yields pernicious effects on adult economic outcomes. Moreover, these results are robust to alternative variable specifications and cousin fixed effects that net out potentially unobserved confounders, such as the inheritance of neighborhood disadvantage across three generations. Copyright © 2017. Published by Elsevier Inc.

  3. The Challenge of Parenting Girls in Neighborhoods of Different Perceived Quality

    Directory of Open Access Journals (Sweden)

    Lia Ahonen

    2014-08-01

    Full Text Available It is well-known that disadvantaged neighborhoods, as officially identified through census data, harbor higher numbers of delinquent individuals than advantaged neighborhoods. What is much less known is whether parents’ perception of the neighborhood problems predicts low parental engagement with their girls and, ultimately, how this is related to girls’ delinquency, including violence. This paper elucidates these issues by examining data from the Pittsburgh Girls Study, including parent-report of neighborhood problems and level of parental engagement and official records and girl-reported delinquency at ages 15, 16, and 17. Results showed higher stability over time for neighborhood problems and parental engagement than girls’ delinquency. Parents’ perception of their neighborhood affected the extent to which parents engaged in their girls’ lives, but low parental engagement did not predict girls being charged for offending at age 15, 16 or 17. These results were largely replicated for girls’ self-reported delinquency with the exception that low parental engagement at age 16 was predictive of the frequency of girls’ self-reported delinquency at age 17 as well. The results, because of their implications for screening and early interventions, are relevant to policy makers as well as practitioners.

  4. The effect of neighborhood context on children's academic achievement in China: Exploring mediating mechanisms.

    Science.gov (United States)

    Lei, Lei

    2018-05-01

    Along with the economic reforms, rapid urbanization, and the growth of a free land market, Chinese cities witness new forms of neighborhood poverty and increasing residential segregation by social class, migration status, and housing tenure. But little is known about the consequences of the growing social-spatial differentiation for children's educational achievement in China. Using national-scale survey data from the China Family Panel Studies in 2010, this study examines the relationship between neighborhood socioeconomic status (SES) and children's test scores in urban China, and explores the mechanisms through which neighborhood environment is associated with children's academic achievement. The results show that neighborhood SES is positively associated with children's verbal and math test scores after accounting for myriad individual and family characteristics. The relationship between neighborhood SES and test scores is partially explained by neighborhood educational institutions and collective socialization. Peer contagion, neighborhood social organization, or neighborhood physical environment do not explain this relationship. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Ghettoizing outdoor advertising: disadvantage and ad panel density in black neighborhoods.

    Science.gov (United States)

    Kwate, Naa Oyo A; Lee, Tammy H

    2007-01-01

    This study investigated correlates of outdoor advertising panel density in predominantly African American neighborhoods in New York City. Research shows that black neighborhoods have more outdoor advertising space than white neighborhoods, and these spaces disproportionately market alcohol and tobacco advertisements. Thus, understanding the factors associated with outdoor advertising panel density has important implications for public health. We linked 2000 census data with property data at the census block group level to investigate two neighborhood-level determinants of ad density: income level and physical decay. Results showed that block groups were exposed to an average of four ad spaces per 1,000 residents and that vacant lot square footage was a significant positive predictor of ad density. An inverse relationship between median household income and ad density did not reach significance, suggesting that relative affluence did not protect black neighborhoods from being targeted for outdoor advertisements.

  6. Computed tomography perfusion imaging denoising using Gaussian process regression

    International Nuclear Information System (INIS)

    Zhu Fan; Gonzalez, David Rodriguez; Atkinson, Malcolm; Carpenter, Trevor; Wardlaw, Joanna

    2012-01-01

    Brain perfusion weighted images acquired using dynamic contrast studies have an important clinical role in acute stroke diagnosis and treatment decisions. However, computed tomography (CT) images suffer from low contrast-to-noise ratios (CNR) as a consequence of the limitation of the exposure to radiation of the patient. As a consequence, the developments of methods for improving the CNR are valuable. The majority of existing approaches for denoising CT images are optimized for 3D (spatial) information, including spatial decimation (spatially weighted mean filters) and techniques based on wavelet and curvelet transforms. However, perfusion imaging data is 4D as it also contains temporal information. Our approach using Gaussian process regression (GPR), which takes advantage of the temporal information, to reduce the noise level. Over the entire image, GPR gains a 99% CNR improvement over the raw images and also improves the quality of haemodynamic maps allowing a better identification of edges and detailed information. At the level of individual voxel, GPR provides a stable baseline, helps us to identify key parameters from tissue time-concentration curves and reduces the oscillations in the curve. GPR is superior to the comparable techniques used in this study. (note)

  7. Coherence of the vortex Bessel-Gaussian beam in turbulent atmosphere

    Science.gov (United States)

    Lukin, Igor P.

    2017-11-01

    In this paper the theoretical research of coherent properties of the vortex Bessel-Gaussian optical beams propagating in turbulent atmosphere are developed. The approach to the analysis of this problem is based on the analytical solution of the equation for the transverse second-order mutual coherence function of a field of optical radiation. The behavior of integral scale of coherence degree of vortex Bessel-Gaussian optical beams depending on parameters of an optical beam and characteristics of turbulent atmosphere is particularly considered. It is shown that the integral scale of coherence degree of a vortex Bessel-Gaussian optical beam essentially depends on value of a topological charge of a vortex optical beam. With increase in a topological charge of a vortex Bessel-Gaussian optical beam the value of integral scale of coherence degree of a vortex Bessel-Gaussian optical beam are decreased.

  8. Fitting the Fractional Polynomial Model to Non-Gaussian Longitudinal Data

    Directory of Open Access Journals (Sweden)

    Ji Hoon Ryoo

    2017-08-01

    Full Text Available As in cross sectional studies, longitudinal studies involve non-Gaussian data such as binomial, Poisson, gamma, and inverse-Gaussian distributions, and multivariate exponential families. A number of statistical tools have thus been developed to deal with non-Gaussian longitudinal data, including analytic techniques to estimate parameters in both fixed and random effects models. However, as yet growth modeling with non-Gaussian data is somewhat limited when considering the transformed expectation of the response via a linear predictor as a functional form of explanatory variables. In this study, we introduce a fractional polynomial model (FPM that can be applied to model non-linear growth with non-Gaussian longitudinal data and demonstrate its use by fitting two empirical binary and count data models. The results clearly show the efficiency and flexibility of the FPM for such applications.

  9. GaussianCpG: a Gaussian model for detection of CpG island in human genome sequences.

    Science.gov (United States)

    Yu, Ning; Guo, Xuan; Zelikovsky, Alexander; Pan, Yi

    2017-05-24

    As crucial markers in identifying biological elements and processes in mammalian genomes, CpG islands (CGI) play important roles in DNA methylation, gene regulation, epigenetic inheritance, gene mutation, chromosome inactivation and nuclesome retention. The generally accepted criteria of CGI rely on: (a) %G+C content is ≥ 50%, (b) the ratio of the observed CpG content and the expected CpG content is ≥ 0.6, and (c) the general length of CGI is greater than 200 nucleotides. Most existing computational methods for the prediction of CpG island are programmed on these rules. However, many experimentally verified CpG islands deviate from these artificial criteria. Experiments indicate that in many cases %G+C is human genome. We analyze the energy distribution over genomic primary structure for each CpG site and adopt the parameters from statistics of Human genome. The evaluation results show that the new model can predict CpG islands efficiently by balancing both sensitivity and specificity over known human CGI data sets. Compared with other models, GaussianCpG can achieve better performance in CGI detection. Our Gaussian model aims to simplify the complex interaction between nucleotides. The model is computed not by the linear statistical method but by the Gaussian energy distribution and accumulation. The parameters of Gaussian function are not arbitrarily designated but deliberately chosen by optimizing the biological statistics. By using the pseudopotential analysis on CpG islands, the novel model is validated on both the real and artificial data sets.

  10. Transient Properties of a Bistable System with Delay Time Driven by Non-Gaussian and Gaussian Noises: Mean First-Passage Time

    International Nuclear Information System (INIS)

    Li Dongxi; Xu Wei; Guo Yongfeng; Li Gaojie

    2008-01-01

    The mean first-passage time of a bistable system with time-delayed feedback driven by multiplicative non-Gaussian noise and additive Gaussian white noise is investigated. Firstly, the non-Markov process is reduced to the Markov process through a path-integral approach; Secondly, the approximate Fokker-Planck equation is obtained by applying the unified coloured noise approximation, the small time delay approximation and the Novikov Theorem. The functional analysis and simplification are employed to obtain the approximate expressions of MFPT. The effects of non-Gaussian parameter (measures deviation from Gaussian character) r, the delay time τ, the noise correlation time τ 0 , the intensities D and α of noise on the MFPT are discussed. It is found that the escape time could be reduced by increasing the delay time τ, the noise correlation time τ 0 , or by reducing the intensities D and α. As far as we know, this is the first time to consider the effect of delay time on the mean first-passage time in the stochastic dynamical system

  11. Neighborhood, Socioeconomic, and Racial Influence on Chronic Pain.

    Science.gov (United States)

    Maly, Angelika; Vallerand, April Hazard

    2018-02-01

    The purpose of this review is to highlight the neighborhood, socioeconomic, and racial influences on chronic pain. Negative influences on the experience of chronic pain are explored and defined as any adverse stressor common in low socioeconomic, urban neighborhoods that potentially contributes to health disparity in African Americans experiencing chronic pain. The multifactorial influences on chronic pain disparity in African Americans are explored and expounded upon in this review of existing evidence. Databases used for the search included CINAHL, PubMed, and PsycArticles. The experience of chronic pain is multifaceted, existing with multiple comorbidities and lasting consequences. To improve the burden of chronic pain requires a multifactorial assessment that considers neighborhood risk factors, emphasis on environmental stressors, limitations to support networks, barriers to physical activity, and access to primary care providers with whom communication is open and without bias. A comprehensive assessment of barriers will aid in the development of interventions that reach beyond the physical factors of chronic pain, also considering the psychosocial barriers to improving the burden of chronic pain in African Americans living in impoverished urban neighborhoods. Copyright © 2017 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  12. Perceived neighborhood social resources as determinants of prosocial behavior in early adolescence.

    Science.gov (United States)

    Lenzi, Michela; Vieno, Alessio; Perkins, Douglas D; Pastore, Massimiliano; Santinello, Massimo; Mazzardis, Sonia

    2012-09-01

    The present study aims to develop an integrative model that links neighborhood behavioral opportunities and social resources (neighborhood cohesion, neighborhood friendship and neighborhood attachment) to prosocial (sharing, helping, empathic) behavior in early adolescence, taking into account the potential mediating role of perceived support of friends. Path analysis was used to test the proposed theoretical model in a sample of 1,145 Italian early adolescents (6th through 8th graders). More perceived opportunities and social resources in the neighborhood are related to higher levels of adolescent prosocial behavior, and this relationship is partially mediated by perceived social support from friends. The results offer promising implications for future research and intervention programs that aim to modify social systems to improve child and adolescent social competencies.

  13. Planning and Partnerships for the Renewal of Urban Neighborhoods

    Science.gov (United States)

    Sterrett, Stephen A.

    2009-01-01

    Urban universities are a key resource for municipal government, businesses, community organizations, and citizens to foster partnerships for successful renewal of distressed urban neighborhoods. From its experience over the past decade, the Ohio State University has created a successful model for engagement with its neighborhoods and the City of…

  14. Generating Realistic Labelled, Weighted Random Graphs

    Directory of Open Access Journals (Sweden)

    Michael Charles Davis

    2015-12-01

    Full Text Available Generative algorithms for random graphs have yielded insights into the structure and evolution of real-world networks. Most networks exhibit a well-known set of properties, such as heavy-tailed degree distributions, clustering and community formation. Usually, random graph models consider only structural information, but many real-world networks also have labelled vertices and weighted edges. In this paper, we present a generative model for random graphs with discrete vertex labels and numeric edge weights. The weights are represented as a set of Beta Mixture Models (BMMs with an arbitrary number of mixtures, which are learned from real-world networks. We propose a Bayesian Variational Inference (VI approach, which yields an accurate estimation while keeping computation times tractable. We compare our approach to state-of-the-art random labelled graph generators and an earlier approach based on Gaussian Mixture Models (GMMs. Our results allow us to draw conclusions about the contribution of vertex labels and edge weights to graph structure.

  15. Feasibility study on the least square method for fitting non-Gaussian noise data

    Science.gov (United States)

    Xu, Wei; Chen, Wen; Liang, Yingjie

    2018-02-01

    This study is to investigate the feasibility of least square method in fitting non-Gaussian noise data. We add different levels of the two typical non-Gaussian noises, Lévy and stretched Gaussian noises, to exact value of the selected functions including linear equations, polynomial and exponential equations, and the maximum absolute and the mean square errors are calculated for the different cases. Lévy and stretched Gaussian distributions have many applications in fractional and fractal calculus. It is observed that the non-Gaussian noises are less accurately fitted than the Gaussian noise, but the stretched Gaussian cases appear to perform better than the Lévy noise cases. It is stressed that the least-squares method is inapplicable to the non-Gaussian noise cases when the noise level is larger than 5%.

  16. Neighborhood socioeconomic status, sleep duration and napping in middle-to-old aged US men and women.

    Science.gov (United States)

    Xiao, Qian; Hale, Lauren

    2018-04-25

    Earlier studies have linked neighborhood disadvantage with poor sleep outcomes. However, little is known about the association between changes in one's neighborhood over time and night sleep and napping. In over 300,000 middle-to-old aged Americans, we examined neighborhood socioeconomic status (SES) and change in neighborhood SES in relation to nocturnal sleep duration and napping. Nocturnal sleep duration and daytime napping were self-reported at baseline (1995-1996). Participants also reported baseline residential addresses, which were linked to US censuses. We derived a neighborhood SES index using census variables and calculated the baseline level and change (1990-2000) in neighborhood SES. Multinomial logistic regression was used to estimate the associations between neighborhood SES over time and nocturnal sleep and napping. Lower baseline neighborhood SES was associated short sleep, long sleep and napping. When compared with the highest quintile of neighborhood SES, the lowest was associated with 46% and 72% increase in relative risk (RR) of reporting very short (nap in men and women, respectively. Moreover, a decrease in neighborhood SES was associated with higher RR of reporting very short sleep in women; while an improvement in neighborhood SES was associated with an increase in RR of long sleep in men. Neighborhood disadvantage and worsening neighborhood conditions were associated with unhealthy sleep behaviors. These results reinforce a growing literature on the potential importance of neighborhood context for understanding sleep health.

  17. Coincidence Imaging and interference with coherent Gaussian beams

    Institute of Scientific and Technical Information of China (English)

    CAI Yang-jian; ZHU Shi-yao

    2006-01-01

    we present a theoretical study of coincidence imaging and interference with coherent Gaussian beams The equations for the coincidence image formation and interference fringes are derived,from which it is clear that the imaging is due to the corresponding focusing in the two paths .The quality and visibility of the images and fringes can be high simultaneously.The nature of the coincidence imaging and interference between quantum entangled photon pairs and coherent Gaussian beams are different .The coincidence image with coherent Gaussian beams is due to intensity-intensity correspondence,a classical nature,while that with entangled photon pairs is due to the amplitude correlation a quantum nature.

  18. Neighborhood Effects in a Behavioral Randomized Controlled Trial

    OpenAIRE

    Pruitt, Sandi L.; Leonard, Tammy; Murdoch, James; Hughes, Amy; McQueen, Amy; Gupta, Samir

    2014-01-01

    Randomized controlled trials (RCTs) of interventions intended to modify health behaviors may be influenced by neighborhood effects which can impede unbiased estimation of intervention effects. Examining a RCT designed to increase colorectal cancer (CRC) screening (N=5,628), we found statistically significant neighborhood effects: average CRC test use among neighboring study participants was significantly and positively associated with individual patient’s CRC test use. This potentially import...

  19. The Synergy of Family and Neighborhood on Rural Dating Violence Victimization.

    Science.gov (United States)

    Foshee, Vangie A; Chang, Ling-Yin; McNaughton Reyes, H Luz; Chen, May S; Ennett, Susan T

    2015-09-01

    Rural adolescents are at high risk for dating violence victimization (DVV), which has serious negative consequences. Understanding more about the conditions that increase DVV risk for rural adolescents is needed to inform prevention efforts. In response to calls for examining the influence of upper levels of the social ecology on adolescent dating violence, this study examined whether associations between the family context and physical DVV were conditioned by the characteristics of the neighborhoods in which the family resided. Data were from a multi-wave longitudinal study of 3,236 rural adolescents nested in 65 block groups, which defined neighborhoods. Data were collected between 2003 and 2005. Multilevel growth curve modeling was conducted in 2014 to test hypothesized synergistic effects of the family and neighborhood on trajectories of physical DVV from grade 8 to 12. Low parental closeness was a DVV risk in residentially stable (pFamily aggression was a DVV risk, regardless of neighborhood characteristics (p=0.001). Low parental monitoring and rule setting were not DVV risks and their effects were not moderated by neighborhood characteristics. Neighborhood ethnic heterogeneity was significantly (pviolence were not associated with DVV. None of the effects varied by sex of the adolescent, across time (grade), or by the combination of sex and time. Findings demonstrate the importance of considering the family and neighborhood, and particularly their synergistic effects in efforts to prevent adolescent DVV. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  20. Neighborhood and family intersections: prospective implications for Mexican American adolescents' mental health.

    Science.gov (United States)

    White, Rebecca M B; Roosa, Mark W; Zeiders, Katharine H

    2012-10-01

    We present an integrated model for understanding Mexican American youth mental health within family, neighborhood, and cultural contexts. We combined two common perspectives on neighborhood effects to hypothesize that (a) parents' perceptions of neighborhood risk would negatively impact their children's mental health by disrupting key parenting and family processes, and (b) objective neighborhood risk would alter the effect parent and family processes had on youth mental health. We further incorporated a cultural perspective to hypothesize that an ethnic minority group's culture-specific values may support parents to successfully confront neighborhood risk. We provided a conservative test of the integrated model by simultaneously examining three parenting and family process variables: maternal warmth, maternal harsh parenting, and family cohesion. The hypothesized model was estimated prospectively in a diverse, community-based sample of Mexican American adolescents and their mothers (N = 749) living in the southwestern United States. Support for specific elements of the hypothesized model varied depending on the parenting or family process variable examined. For family cohesion results were consistent with the combined neighborhood perspectives. The effects of maternal warmth on youth mental health were altered by objective neighborhood risk. For harsh parenting, results were somewhat consistent with the cultural perspective. The value of the integrated model for research on the impacts of family, neighborhood, and cultural contexts on youth mental health are discussed, as are implications for preventive interventions for Mexican American families and youth. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  1. Neighborhood and Family Intersections: Prospective Implications for Mexican American Adolescents’ Mental Health

    Science.gov (United States)

    White, Rebecca M. B.; Roosa, Mark W.; Zeiders, Katharine H.

    2012-01-01

    We present an integrated model for understanding Mexican American youth mental health within family, neighborhood, and cultural contexts. We combined two common perspectives on neighborhood effects to hypothesize that (a) parents’ perceptions of neighborhood risk would negatively impact their children’s mental health by disrupting key parenting and family processes, and (b) objective neighborhood risk would alter the effect parent and family processes had on youth mental health. We further incorporated a cultural perspective to hypothesize that an ethnic minority group’s culture-specific values may support parents to successfully confront neighborhood risk. We provided a conservative test of the integrated model by simultaneously examining three parenting and family process variables: maternal warmth, maternal harsh parenting, and family cohesion. The hypothesized model was estimated prospectively in a diverse, community-based sample of Mexican American adolescents and their mothers (N = 749) living in the Southwestern, U.S. Support for specific elements of the hypothesized model varied depending on the parenting or family process variable examined. For family cohesion results were consistent with the combined neighborhood perspectives. The effects of maternal warmth on youth mental health were altered by objective neighborhood risk. For harsh parenting results were somewhat consistent with the cultural perspective. The value of the integrated model for research on the impacts of family, neighborhood, and cultural contexts on youth mental health are discussed, as are implications for preventive interventions for Mexican American families and youth. PMID:22866932

  2. Reacting to Neighborhood Cues?

    DEFF Research Database (Denmark)

    Danckert, Bolette; Dinesen, Peter Thisted; Sønderskov, Kim Mannemar

    2017-01-01

    is founded on politically sophisticated individuals having a greater comprehension of news and other mass-mediated sources, which makes them less likely to rely on neighborhood cues as sources of information relevant for political attitudes. Based on a unique panel data set with fine-grained information...

  3. Relationship of corporal punishment and antisocial behavior by neighborhood.

    Science.gov (United States)

    Grogan-Kaylor, Andrew

    2005-10-01

    To examine the relationship of corporal punishment with children's behavior problems while accounting for neighborhood context and while using stronger statistical methods than previous literature in this area, and to examine whether different levels of corporal punishment have different effects in different neighborhood contexts. Longitudinal cohort study. General community. 1943 mother-child pairs from the National Longitudinal Survey of Youth. Internalizing and externalizing behavior problem scales of the Behavior Problems Index. Parental use of corporal punishment was associated with a 0.71 increase (Pcorporal punishment and children's externalizing behavior problems was not dependent on neighborhood context. The research found no discernible relationship between corporal punishment and internalizing behavior problems.

  4. EDITORIAL: Non-linear and non-Gaussian cosmological perturbations Non-linear and non-Gaussian cosmological perturbations

    Science.gov (United States)

    Sasaki, Misao; Wands, David

    2010-06-01

    In recent years there has been a resurgence of interest in the study of non-linear perturbations of cosmological models. This has been the result of both theoretical developments and observational advances. New theoretical challenges arise at second and higher order due to mode coupling and the need to develop new gauge-invariant variables beyond first order. In particular, non-linear interactions lead to deviations from a Gaussian distribution of primordial perturbations even if initial vacuum fluctuations are exactly Gaussian. These non-Gaussianities provide an important probe of models for the origin of structure in the very early universe. We now have a detailed picture of the primordial distribution of matter from surveys of the cosmic microwave background, notably NASA's WMAP satellite. The situation will continue to improve with future data from the ESA Planck satellite launched in 2009. To fully exploit these data cosmologists need to extend non-linear cosmological perturbation theory beyond the linear theory that has previously been sufficient on cosmological scales. Another recent development has been the realization that large-scale structure, revealed in high-redshift galaxy surveys, could also be sensitive to non-linearities in the primordial curvature perturbation. This focus section brings together a collection of invited papers which explore several topical issues in this subject. We hope it will be of interest to theoretical physicists and astrophysicists alike interested in understanding and interpreting recent developments in cosmological perturbation theory and models of the early universe. Of course it is only an incomplete snapshot of a rapidly developing field and we hope the reader will be inspired to read further work on the subject and, perhaps, fill in some of the missing pieces. This focus section is dedicated to the memory of Lev Kofman (1957-2009), an enthusiastic pioneer of inflationary cosmology and non-Gaussian perturbations.

  5. Perception of neighborhood safety and reported childhood lifetime asthma in the United States (U.S.: a study based on a national survey.

    Directory of Open Access Journals (Sweden)

    S V Subramanian

    2009-06-01

    Full Text Available Recent studies have emphasized the role of psychosocial stressors as a determinant of asthma, and neighborhoods can be a potential source of such stressors. We investigated the association between parental perception of neighborhood safety and reported lifetime asthma among children.Data for the study came from the 2003-04 National Survey of Children Health (NSCH; a nationally representative cross-sectional sample of children aged 0-17 years. Demographic, socioeconomic and behavioral covariates were included in the study. Models were estimated after taking account of weighting and complex survey design. Parental report of whether the child has ever been diagnosed with asthma by a physician was used to define the outcome. Parental report of perception of neighborhood safety was the main exposure. In unadjusted models, the odds ratio (OR for reporting asthma associated with living in neighborhoods that were perceived to be sometimes or never safe was 1.36 (95% confidence intervals [CI] 1.21, 1.53 compared to living in neighborhoods that were perceived to be always safe. Adjusting for covariates including exposure to second hand tobacco smoke, mother's self-rated health, child's physical activity and television viewing attenuated this association (OR 1.25, 95% CI 1.08, 1.43. In adjusted models, the increased odds ratio for reporting asthma was also higher among those who perceived neighborhoods as being usually safe (OR 1.15 95% CI 1.06, 1.26, as compared to always safe, suggestive of a dose-response relationship, with the differentials for usually safe and never safe being statistically significant (p = 0.009.Psychosocial stressors may be important risk factors that may impact the pathogenesis of asthma and/or contribute to asthma morbidity by triggering exacerbations through neuroimmunologic mechanisms, as well as social mechanisms.

  6. Integral momenta of vortex Bessel-Gaussian beams in turbulent atmosphere.

    Science.gov (United States)

    Lukin, Igor P

    2016-04-20

    The orbital angular momentum of vortex Bessel-Gaussian beams propagating in turbulent atmosphere is studied theoretically. The field of an optical beam is determined through the solution of the paraxial wave equation for a randomly inhomogeneous medium with fluctuations of the refraction index of the turbulent atmosphere. Peculiarities in the behavior of the total power of the vortex Bessel-Gaussian beam at the receiver (or transmitter) are examined. The dependence of the total power of the vortex Bessel-Gaussian beam on optical beam parameters, namely, the transverse wave number of optical radiation, amplitude factor radius, and, especially, topological charge of the optical beam, is analyzed in detail. It turns out that the mean value of the orbital angular momentum of the vortex Bessel-Gaussian beam remains constant during propagation in the turbulent atmosphere. It is shown that the variance of fluctuations of the orbital angular momentum of the vortex Bessel-Gaussian beam propagating in turbulent atmosphere calculated with the "mean-intensity" approximation is equal to zero identically. Thus, it is possible to declare confidently that the variance of fluctuations of the orbital angular momentum of the vortex Bessel-Gaussian beam in turbulent atmosphere is not very large.

  7. Health selection into neighborhoods among patients enrolled in a clinical trial

    Directory of Open Access Journals (Sweden)

    Mariana C. Arcaya

    2017-12-01

    Full Text Available Health selection into neighborhoods may contribute to geographic health disparities. We demonstrate the potential for clinical trial data to help clarify the causal role of health on locational attainment. We used data from the 20-year United Kingdom Prospective Diabetes Study (UKPDS to explore whether random assignment to intensive blood-glucose control therapy, which improved long-term health outcomes after median 10 years follow-up, subsequently affected what neighborhoods patients lived in. We extracted postcode-level deprivation indices for the 2710 surviving participants of UKPDS living in England at study end in 1996/1997. We observed small neighborhood advantages in the intensive versus conventional therapy group, although these differences were not statistically significant. This analysis failed to show conclusive evidence of health selection into neighborhoods, but data suggest the hypothesis may be worthy of exploration in other clinical trials or in a meta-analysis. Keywords: Neighborhoods, Self-selection, Health, Equity, Socioeconomic status

  8. Ultrawide Bandwidth Receiver Based on a Multivariate Generalized Gaussian Distribution

    KAUST Repository

    Ahmed, Qasim Zeeshan

    2015-04-01

    Multivariate generalized Gaussian density (MGGD) is used to approximate the multiple access interference (MAI) and additive white Gaussian noise in pulse-based ultrawide bandwidth (UWB) system. The MGGD probability density function (pdf) is shown to be a better approximation of a UWB system as compared to multivariate Gaussian, multivariate Laplacian and multivariate Gaussian-Laplacian mixture (GLM). The similarity between the simulated and the approximated pdf is measured with the help of modified Kullback-Leibler distance (KLD). It is also shown that MGGD has the smallest KLD as compared to Gaussian, Laplacian and GLM densities. A receiver based on the principles of minimum bit error rate is designed for the MGGD pdf. As the requirement is stringent, the adaptive implementation of the receiver is also carried out in this paper. Training sequence of the desired user is the only requirement when implementing the detector adaptively. © 2002-2012 IEEE.

  9. Living alone and depression: the modifying role of the perceived neighborhood environment.

    Science.gov (United States)

    Stahl, Sarah T; Beach, Scott R; Musa, Donald; Schulz, Richard

    2017-10-01

    Older adults who live alone are more likely to report feelings of depression than those who live with a spouse or other family members. This study examines the effects of residential status and perceived neighborhood characteristics on depression in middle-aged and older adults. This study is based on a probability sample of 1049 adults aged 55-98 years (M = 69 years) residing in Allegheny County, Pittsburgh, PA, USA in 2014. Thirty percent of participants reported living alone. We tested a multivariate model using living alone (vs. living with a family member or others) and perceived neighborhood physical and social quality as predictors of depressive symptomatology while controlling for age, sex, race, education, and disability. Living alone (compared to living with a family member) was associated with elevated levels of depressive symptomatology. However, perceptions of neighborhood social quality moderated this association. Living alone was more highly associated with depression when the perceived social quality of the neighborhood was low. Neighborhood social quality was not associated with depression among older adults who lived with a family member. Perceptions of neighborhood physical quality were not significantly associated with depression. Perceptions of good neighborhood social quality is important for adults who live alone, in terms of fewer symptoms of depression.

  10. Neighborhood-Level Poverty at Menarche and Prepregnancy Obesity in African-American Women.

    Science.gov (United States)

    Cassidy-Bushrow, Andrea E; Peters, Rosalind M; Burmeister, Charlotte; Bielak, Lawrence F; Johnson, Dayna A

    2016-01-01

    Introduction. Menarche is a critical time point in a woman's reproductive system development; exposures at menarche may influence maternal health. Living in a poorer neighborhood is associated with adult obesity; however, little is known if neighborhood factors at menarche are associated with prepregnancy obesity. Methods. We examined the association of neighborhood-level poverty at menarche with prepregnancy body mass index category in 144 pregnant African-American women. Address at menarche was geocoded to census tract (closest to year of menarche); neighborhood-level poverty was defined as the proportion of residents living under the federal poverty level. Cumulative logistic regression was used to examine the association of neighborhood-level poverty at menarche, in quartiles, with categorical prepregnancy BMI. Results. Before pregnancy, 59 (41%) women were obese. Compared to women in the lowest neighborhood-level poverty quartile, women in the highest quartile had 2.9 [1.2, 6.9] times higher odds of prepregnancy obesity; this was slightly attenuated after adjusting for age, marital status, education, and parity (odds ratio: 2.3 [0.9, 6.3]). Conclusions. Living in a higher poverty neighborhood at menarche is associated with prepregnancy obesity in African-American women. Future studies are needed to better understand the role of exposures in menarche on health in pregnancy.

  11. WE-E-213CD-02: Gaussian Weighted Multi-Atlas Based Segmentation for Head and Neck Radiotherapy Planning.

    Science.gov (United States)

    Peroni, M; Sharp, G C; Golland, P; Baroni, G

    2012-06-01

    To develop a multi-atlas segmentation strategy for IMRT head and neck therapy planning. The method was tested on thirty-one head and neck simulation CTs, without demographic or pathology pre-clustering. We compare Fixed Number (FN) and Thresholding (TH) selection (based on normalized mutual information ranking) of the atlases to be included for current patient segmentation. Next step is a pairwise demons Deformable Registration (DR) onto current patient CT. DR was extended to automatically compensate for patient different field of view. Propagated labels are combined according to a Gaussian Weighted (GW) fusion rule, adapted to poor soft tissues contrast. Agreement with manual segmentation was quantified in terms of Dice Similarity Coefficient (DSC). Selection methods, number of atlases used, as well as GW, average and majority voting fusion were discriminated by means of Friedman Test (a=5%). Experimental tuning of the algorithm parameters was performed on five patients, deriving an optimal configuration for each structure. DSC reduction was not significant when ten or more atlases are selected, whereas DSC for single most similar atlas selection is 10% lower in median. DSC of FN selection rule were significantly higher for most structures. Tubular structures may benefit from computing average contour rather than looking at the singular voxel contribution, whereas the best performing strategy for all other structures was GW. When half database is selected, final median DSC were 0.86, 0.80, 0.51, 0.81, 0.69 and 0.79 for mandible, spine, optical nerves, eyes, parotids and brainstem respectively. We developed an efficient algorithm for multiatlas based segmentation of planning CT volumes, based on DR and GW. FN selection of database atlases is foreseen to increase computational efficiency. The absence of clinical pre-clustering and specific imaging protocol on database subjects makes the results closer to real clinical application. "Progetto Roberto Rocca" funded by

  12. Changes in Neighborhood Poverty from 1990 to 2000 and Youth's Problem Behaviors

    Science.gov (United States)

    Leventhal, Tama; Brooks-Gunn, Jeanne

    2011-01-01

    This study used data from the Project on Human Development in Chicago Neighborhoods, a multilevel, longitudinal study of children sampled from 80 diverse neighborhoods, to explore associations among changes in neighborhood poverty from 1990 to 2000 and changes in youth's internalizing problems and property and violent offenses over 6 years (N =…

  13. Exploring the evolution of node neighborhoods in Dynamic Networks

    Science.gov (United States)

    Orman, Günce Keziban; Labatut, Vincent; Naskali, Ahmet Teoman

    2017-09-01

    Dynamic Networks are a popular way of modeling and studying the behavior of evolving systems. However, their analysis constitutes a relatively recent subfield of Network Science, and the number of available tools is consequently much smaller than for static networks. In this work, we propose a method specifically designed to take advantage of the longitudinal nature of dynamic networks. It characterizes each individual node by studying the evolution of its direct neighborhood, based on the assumption that the way this neighborhood changes reflects the role and position of the node in the whole network. For this purpose, we define the concept of neighborhood event, which corresponds to the various transformations such groups of nodes can undergo, and describe an algorithm for detecting such events. We demonstrate the interest of our method on three real-world networks: DBLP, LastFM and Enron. We apply frequent pattern mining to extract meaningful information from temporal sequences of neighborhood events. This results in the identification of behavioral trends emerging in the whole network, as well as the individual characterization of specific nodes. We also perform a cluster analysis, which reveals that, in all three networks, one can distinguish two types of nodes exhibiting different behaviors: a very small group of active nodes, whose neighborhood undergo diverse and frequent events, and a very large group of stable nodes.

  14. Neighborhood Deprivation and Childhood Asthma Outcomes, Accounting for Insurance Coverage.

    Science.gov (United States)

    Nkoy, Flory L; Stone, Bryan L; Knighton, Andrew J; Fassl, Bernhard A; Johnson, Joseph M; Maloney, Christopher G; Savitz, Lucy A

    2018-01-09

    Collecting social determinants data is challenging. We assigned patients a neighborhood-level social determinant measure, the area of deprivation index (ADI), by using census data. We then assessed the association between neighborhood deprivation and asthma hospitalization outcomes and tested the influence of insurance coverage. A retrospective cohort study of children 2 to 17 years old admitted for asthma at 8 hospitals. An administrative database was used to collect patient data, including hospitalization outcomes and neighborhood deprivation status (ADI scores), which were grouped into quintiles (ADI 1, the least deprived neighborhoods; ADI 5, the most deprived neighborhoods). We used multivariable models, adjusting for covariates, to assess the associations and added a neighborhood deprivation status and insurance coverage interaction term. A total of 2270 children (median age 5 years; 40.6% girls) were admitted for asthma. We noted that higher ADI quintiles were associated with greater length of stay, higher cost, and more asthma readmissions ( P < .05 for most quintiles). Having public insurance was independently associated with greater length of stay (β: 1.171; 95% confidence interval [CI]: 1.117-1.228; P < .001), higher cost (β: 1.147; 95% CI: 1.093-1.203; P < .001), and higher readmission odds (odds ratio: 1.81; 95% CI: 1.46-2.24; P < .001). There was a significant deprivation-insurance effect modification, with public insurance associated with worse outcomes and private insurance with better outcomes across ADI quintiles ( P < .05 for most combinations). Neighborhood-level ADI measure is associated with asthma hospitalization outcomes. However, insurance coverage modifies this relationship and needs to be considered when using the ADI to identify and address health care disparities. Copyright © 2018 by the American Academy of Pediatrics.

  15. Neighborhood socioeconomic deprivation characteristics in child (0-18 years) health studies: a review.

    Science.gov (United States)

    van Vuuren, C Leontine; Reijneveld, Sijmen A; van der Wal, Marcel F; Verhoeff, Arnoud P

    2014-09-01

    Growing up in socioeconomically deprived neighborhoods has been shown to have negative health effects on children. However, the most recent review on which measures are used to investigate the association between neighborhood characteristics and child (0-18 year) health included studies only until 2004. Insight into more recent research is needed for the further development of these measures. To review neighborhood socioeconomic deprivation characteristics used in recent studies investigating the relationship between neighborhood socioeconomic deprivation and child health. Sensitive search in MEDLINE, Embase, PsycINFO, Sociological Abstracts databases (2004-2013). Ultimately, 19 studies were included. We found ten neighborhood socioeconomic deprivation constructs, of which income/wealth, employment, and education were most frequently used. The choice for neighborhood characteristics seemed independent of the health outcome and in most cases was not based on a specific theoretical background or earlier work. Studies vary regarding study designs, measures and outcomes. Researchers should clearly specify their choice of neighborhood socioeconomic deprivation characteristics; preferably, these should be theory-based and used consistently. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Neighborhood Environment and Self-Rated Health Among Urban Older Adults

    Directory of Open Access Journals (Sweden)

    Arlesia Mathis PhD

    2015-09-01

    Full Text Available Objective: This study examines associations between neighborhood environment and self-rated health (SRH among urban older adults. Method: We selected 217 individuals aged 65+ living in a de-industrialized Midwestern city who answered questions on the 2009 Speak to Your Health survey. The relationship between neighborhood environment and SRH was analyzed using regression models. Neighborhood variables included social support and participation, perceived racism, and crime. Additional models included actual crime indices to compare differences between perceived and actual crime. Results: Seniors who have poor SRH are 21% more likely to report fear of crime than seniors with excellent SRH ( p = .01. Additional analyses revealed Black seniors are 7% less likely to participate in social activities ( p = .005 and 4% more likely to report experiencing racism ( p < .001. Discussion: More than 80% of older adults live in urban areas. By 2030, older adults will account for 20% of the U.S. population. Given the increasing numbers of older adults living in urban neighborhoods, studies such as this one are important. Mitigating environmental influences in the neighborhood that are associated with poor SRH may allow urban older adults to maintain health and reduce disability.

  17. Relative entropy as a measure of entanglement for Gaussian states

    Institute of Scientific and Technical Information of China (English)

    Lu Huai-Xin; Zhao Bo

    2006-01-01

    In this paper, we derive an explicit analytic expression of the relative entropy between two general Gaussian states. In the restriction of the set for Gaussian states and with the help of relative entropy formula and Peres-Simon separability criterion, one can conveniently obtain the relative entropy entanglement for Gaussian states. As an example,the relative entanglement for a two-mode squeezed thermal state has been obtained.

  18. Neighborhood Contexts and Marijuana Use Among Urban Dwelling Emerging Adult Men.

    Science.gov (United States)

    Taggart, Tamara; Brown, Andre L; Kershaw, Trace

    2018-01-01

    Neighborhoods are key socio-environmental contexts for marijuana use during emerging adulthood. This study examined the relationships between neighborhood context, traditional masculine norms (status, toughness, and anti-femininity), and marijuana use among 119 majority African American emerging adult men in a small urban community. Poisson regression models were used to determine the associations between neighborhood problems, social cohesion, and marijuana use. Moderator effects were examined to determine if masculinities modified these associations. Neighborhood problems and social cohesion were positively associated with marijuana use. Men who had a lower endorsement of some traditional masculine norms had greater marijuana use compared to men with a higher endorsement of these norms. These findings have implications for intervention strategies and policies.

  19. Investigating the relationship between neighborhood experiences and psychiatric distress for individuals with serious mental illness.

    Science.gov (United States)

    Kloos, Bret; Townley, Greg

    2011-03-01

    The present study examined the relationships between how research participants experienced their neighborhood, their neighborhood social climate, and psychological well-being. Participants (n = 525) were residents of supported housing programs who used mental health services at one of 17 community mental health centers in South Carolina. Hierarchical regression and mediation analyses were employed to answer research questions. Results suggest that neighbor relations, perceptions of neighborhood safety, and neighborhood satisfaction were significantly associated with perceptions of neighborhood social climate; and neighborhood social climate accounted for a significant amount of the variance in psychiatric distress. Of particular interest, perceptions of neighborhood social climate fully mediated the relationship between the specific reported neighborhood experiences and psychiatric distress. These findings have implications for interventions and policy aimed at promoting integration of individuals with serious mental illness into community settings.

  20. Self-assembled structures of Gaussian nematic particles.

    Science.gov (United States)

    Nikoubashman, Arash; Likos, Christos N

    2010-03-17

    We investigate the stable crystalline configurations of a nematic liquid crystal made of soft parallel ellipsoidal particles interacting via a repulsive, anisotropic Gaussian potential. For this purpose, we use genetic algorithms (GA) in order to predict all relevant and possible solid phase candidates into which this fluid can freeze. Subsequently we present and discuss the emerging novel structures and the resulting zero-temperature phase diagram of this system. The latter features a variety of crystalline arrangements, in which the elongated Gaussian particles in general do not align with any one of the high-symmetry crystallographic directions, a compromise arising from the interplay and competition between anisotropic repulsions and crystal ordering. Only at very strong degrees of elongation does a tendency of the Gaussian nematics to align with the longest axis of the elementary unit cell emerge.

  1. Gaussian quadrature rules for C 1 quintic splines with uniform knot vectors

    KAUST Repository

    Bartoň, Michael

    2017-03-21

    We provide explicit quadrature rules for spaces of C1C1 quintic splines with uniform knot sequences over finite domains. The quadrature nodes and weights are derived via an explicit recursion that avoids numerical solvers. Each rule is optimal, that is, requires the minimal number of nodes, for a given function space. For each of nn subintervals, generically, only two nodes are required which reduces the evaluation cost by 2/32/3 when compared to the classical Gaussian quadrature for polynomials over each knot span. Numerical experiments show fast convergence, as nn grows, to the “two-third” quadrature rule of Hughes et al. (2010) for infinite domains.

  2. Gaussian quadrature rules for C 1 quintic splines with uniform knot vectors

    KAUST Repository

    Barton, Michael; Ait-Haddou, Rachid; Calo, Victor Manuel

    2017-01-01

    We provide explicit quadrature rules for spaces of C1C1 quintic splines with uniform knot sequences over finite domains. The quadrature nodes and weights are derived via an explicit recursion that avoids numerical solvers. Each rule is optimal, that is, requires the minimal number of nodes, for a given function space. For each of nn subintervals, generically, only two nodes are required which reduces the evaluation cost by 2/32/3 when compared to the classical Gaussian quadrature for polynomials over each knot span. Numerical experiments show fast convergence, as nn grows, to the “two-third” quadrature rule of Hughes et al. (2010) for infinite domains.

  3. Neighborhood perceptions and hypertension among low-income black women: a qualitative study

    Directory of Open Access Journals (Sweden)

    Maliyhah Al-Bayan

    2016-10-01

    Full Text Available Abstract Background The majority of studies examining the role of neighborhoods and hypertension-related outcomes have been quantitative in nature and very few studies have examined specific disadvantaged populations, including low-income housing residents. The objective of this study was to use qualitative interviews to explore low-income Black women’s perceptions of their neighborhoods and to understand how those perceptions may affect their health, especially as it relates to blood pressure. Methods Seventeen Black female participants, living in public housing communities in New York City, completed one semi-structured, audiotaped interview in July of 2014. All interviews were transcribed, coded, and analyzed for emerging themes using N’Vivo 10 software. Results Three major themes emerged: (1 social connectedness, (2 stress factors, and (3 availability of food options. For example, factors that caused stress varied throughout the study population. Sources of stress included family members, employment, and uncleanliness within the neighborhood. Many participants attributed their stress to personal issues, such as lack of employment and relationships. In addition, the general consensus among many participants was that there should be a greater density of healthy food options in their neighborhoods. Some believed that the pricing of fresh foods in the neighborhoods should better reflect the financial status of the residents in the community. Conclusions Various neighborhood influences, including neighborhood disorder and lack of healthy food options, are factors that appear to increase Black women’s risk of developing high blood pressure. Implications of this research include the need to develop interventions that promote good neighborhood infrastructure (e.g. healthy food stores to encourage good nutrition habits and well-lit walking paths to encourage daily exercise, in addition to interventions that increase hypertension awareness in

  4. Resonant non-Gaussianity with equilateral properties

    Energy Technology Data Exchange (ETDEWEB)

    Gwyn, Rhiannon [Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Potsdam (Germany); Rummel, Markus [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Westphal, Alexander [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-11-15

    We discuss the effect of superimposing multiple sources of resonant non-Gaussianity, which arise for instance in models of axion inflation. The resulting sum of oscillating shape contributions can be used to ''Fourier synthesize'' different non-oscillating shapes in the bispectrum. As an example we reproduce an approximately equilateral shape from the superposition of O(10) oscillatory contributions with resonant shape. This implies a possible degeneracy between the equilateral-type non-Gaussianity typical of models with non-canonical kinetic terms, such as DBI inflation, and an equilateral-type shape arising from a superposition of resonant-type contributions in theories with canonical kinetic terms. The absence of oscillations in the 2-point function together with the structure of the resonant N-point functions, imply that detection of equilateral non-Gaussianity at a level greater than the PLANCK sensitivity of f{sub NL} {proportional_to}O(5) will rule out a resonant origin. We comment on the questions arising from possible embeddings of this idea in a string theory setting.

  5. Unitarily localizable entanglement of Gaussian states

    International Nuclear Information System (INIS)

    Serafini, Alessio; Adesso, Gerardo; Illuminati, Fabrizio

    2005-01-01

    We consider generic (mxn)-mode bipartitions of continuous-variable systems, and study the associated bisymmetric multimode Gaussian states. They are defined as (m+n)-mode Gaussian states invariant under local mode permutations on the m-mode and n-mode subsystems. We prove that such states are equivalent, under local unitary transformations, to the tensor product of a two-mode state and of m+n-2 uncorrelated single-mode states. The entanglement between the m-mode and the n-mode blocks can then be completely concentrated on a single pair of modes by means of local unitary operations alone. This result allows us to prove that the PPT (positivity of the partial transpose) condition is necessary and sufficient for the separability of (m+n)-mode bisymmetric Gaussian states. We determine exactly their negativity and identify a subset of bisymmetric states whose multimode entanglement of formation can be computed analytically. We consider explicit examples of pure and mixed bisymmetric states and study their entanglement scaling with the number of modes

  6. Neighborhood walkability and walking behavior: the moderating role of action orientation.

    Science.gov (United States)

    Friederichs, Stijn A H; Kremers, Stef P J; Lechner, Lilian; de Vries, Nanne K

    2013-05-01

    In promoting physical activity, it is important to gain insight into environmental factors that facilitate or hinder physical activity and factors that may influence this environment-behavior relationship. As the personality factor of action orientation reflects an individual's capacity to regulate behavior it may act as a moderator in the environment-behavior relationship. The current study addressed the relationship between neighborhood walkability and walking behavior and the influence of action orientation on this relationship. Three hundred and forty-seven Dutch inhabitants [mean age 43.1 (SD 17.1)] completed a web based questionnaire assessing demographic variables, neighborhood walkability (Neighborhood Environment Walkability Scale), variables of the Theory of Planned Behavior, action orientation, and walking behavior. The results show that high levels of neighborhood walkability are positively associated with walking behavior and that this influence is largely unmediated by cognitive processes. A positive influence of neighborhood walkability on walking behavior was identified in the action-oriented subpopulation, whereas in the state-oriented part of the population, this influence was absent. The findings suggest that the influence of neighborhood environment on walking behavior has a relatively large unconscious, automatic component. In addition, the results suggest that the walkability-walking relationship is moderated by action orientation.

  7. Children's active free play in local neighborhoods: a behavioral mapping study.

    Science.gov (United States)

    Veitch, J; Salmon, J; Ball, K

    2008-10-01

    Many Australian children are more sedentary than they should be, and almost one in five are currently overweight or obese. Some children may face difficulties finding opportunities to be active, having poor access to safe public open spaces or having low independent mobility limiting their access to places to play. This study aimed to examine children's access to places in their neighborhood for active free play and how these vary by age, sex and socioeconomic status (SES). Behavioral maps of the local neighborhood were completed by children (8-12 years) from five primary schools across different areas of Melbourne. Children living in low SES outer-urban neighborhoods had to travel greater distances to access local parks compared with those in inner-urban mid and high SES areas. One-third (32%) of children reported an independent mobility range of <100 m from home. In conclusion, for some children opportunities to engage in active free play in the local neighborhood may be limited due to lack of parks in close proximity to home and restricted independent mobility. It is important to collaborate with local governments, urban planners and community groups to improve access to neighborhood parks and to promote a sense of neighborhood safety.

  8. Neighborhood fast food restaurants and fast food consumption: a national study.

    Science.gov (United States)

    Richardson, Andrea S; Boone-Heinonen, Janne; Popkin, Barry M; Gordon-Larsen, Penny

    2011-07-08

    Recent studies suggest that neighborhood fast food restaurant availability is related to greater obesity, yet few studies have investigated whether neighborhood fast food restaurant availability promotes fast food consumption. Our aim was to estimate the effect of neighborhood fast food availability on frequency of fast food consumption in a national sample of young adults, a population at high risk for obesity. We used national data from U.S. young adults enrolled in wave III (2001-02; ages 18-28) of the National Longitudinal Study of Adolescent Health (n = 13,150). Urbanicity-stratified multivariate negative binomial regression models were used to examine cross-sectional associations between neighborhood fast food availability and individual-level self-reported fast food consumption frequency, controlling for individual and neighborhood characteristics. In adjusted analysis, fast food availability was not associated with weekly frequency of fast food consumption in non-urban or low- or high-density urban areas. Policies aiming to reduce neighborhood availability as a means to reduce fast food consumption among young adults may be unsuccessful. Consideration of fast food outlets near school or workplace locations, factors specific to more or less urban settings, and the role of individual lifestyle attitudes and preferences are needed in future research.

  9. Neighborhood fast food restaurants and fast food consumption: A national study

    Directory of Open Access Journals (Sweden)

    Gordon-Larsen Penny

    2011-07-01

    Full Text Available Abstract Background Recent studies suggest that neighborhood fast food restaurant availability is related to greater obesity, yet few studies have investigated whether neighborhood fast food restaurant availability promotes fast food consumption. Our aim was to estimate the effect of neighborhood fast food availability on frequency of fast food consumption in a national sample of young adults, a population at high risk for obesity. Methods We used national data from U.S. young adults enrolled in wave III (2001-02; ages 18-28 of the National Longitudinal Study of Adolescent Health (n = 13,150. Urbanicity-stratified multivariate negative binomial regression models were used to examine cross-sectional associations between neighborhood fast food availability and individual-level self-reported fast food consumption frequency, controlling for individual and neighborhood characteristics. Results In adjusted analysis, fast food availability was not associated with weekly frequency of fast food consumption in non-urban or low- or high-density urban areas. Conclusions Policies aiming to reduce neighborhood availability as a means to reduce fast food consumption among young adults may be unsuccessful. Consideration of fast food outlets near school or workplace locations, factors specific to more or less urban settings, and the role of individual lifestyle attitudes and preferences are needed in future research.

  10. The characteristics of Chinese orthographic neighborhood size effect for developing readers.

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    Full Text Available Orthographic neighborhood size (N size effect in Chinese character naming has been studied in adults. In the present study, we aimed to explore the developmental characteristics of Chinese N size effect. One hundred and seventeen students (40 from the 3(rd grade with mean age of 9 years; 40 from the 5(th grade with mean age of 11 years; 37 from the 7(th grade with mean age of 13 years were recruited in the study. A naming task of Chinese characters was adopted to elucidate N-size- effect development. Reaction times and error rates were recorded. Results showed that children in the 3(rd grade named characters from large neighborhoods faster than named those from small neighborhoods, revealing a facilitatory N size effect; the 5(th graders showed null N size effect; while the 7(th graders showed an inhibitory N size effect, with longer reaction times for the characters from large neighborhoods than for those from small neighborhoods. The change from facilitation to inhibition of neighborhood size effect across grades suggested the transition from broadly tuned to finely tuned lexical representation in reading development, and the possible inhibition from higher frequency neighbors for higher graders.

  11. Sports participation, perceived neighborhood safety, and individual cognitions: how do they interact?

    Directory of Open Access Journals (Sweden)

    Mackenbach Johan P

    2011-07-01

    Full Text Available Abstract Background Little is known about the interaction between individual and environmental determinants of physical activity, although this may be important information for the development of effective interventions. The goal of this paper is to investigate whether perceived neighborhood safety modifies associations between individual cognitions and sports participation. Methods Cross-sectional data were obtained from residents (age 25-75 of 87 neighborhoods in the city of Eindhoven, who participated in the Dutch GLOBE study in 2004 (N = 2474. We used multilevel logistic regression to analyze the interactions between perceived neighborhood safety and individual cognitions (attitude, self-efficacy, social influence, and intention on sports participation (yes/no. Results In its association with sports participation, perceived neighborhood safety interacted significantly with self-efficacy and attitude (p Conclusions Associations between individual cognitions and sports participation depend on neighborhood circumstances, such as perceived neighborhood safety. Interventions to promote sports participation in adults should take the interaction between environmental and individual characteristics into account. More research is needed to find out the causal pathways in individual-environment interactions.

  12. Watch out for the neighborhood trap !A case study on parental perceptions of and strategies to counter risks for children in a disadvantaged neighborhood

    NARCIS (Netherlands)

    Pinkster, F.M.; Droogleever Fortuijn, J.

    2009-01-01

    Neighborhood is seen as one of the many social contexts that shape children's cognitive, emotional and social development. However, the neighborhood context does not simply 'imprint' itself on children, but can be mediated or moderated by other social contexts, in particular the family context

  13. Social capital across urban neighborhoods: A comparison of self-report and observational data

    NARCIS (Netherlands)

    Hill, J.M.; Jobling, R.; Pollet, T.V.; Nettle, D.

    2014-01-01

    Previous self-report survey research has demonstrated significant variation in social trust and neighborhood social ties between two neighborhoods of contrasting socioeconomic fortunes within the same English city. Residents in a deprived neighborhood reported that they trusted their neighbors less

  14. Participation of the Neighborhood Representatives (Mukhtars into Managerial Activities in Local Level: Burdur Case

    Directory of Open Access Journals (Sweden)

    Mustafa LAMBA

    2017-05-01

    Full Text Available Neighborhood representatives (mukhtars are the nearest administrative units to citizens in local level. It is required to take advantage of that the neighborhood representatives know their districts and residents better than central and local government authorities. In addition, it will be appropriate to the principles of subsidiarity and the European Charter of Local Self Government to determine problems and demands of neighborhoods by their representatives. It is necessary to maintain communication channels and keep close relations with neighborhood representatives by local governments to use that advantage efficiently. It is aimed in this study to determine the participation level of neighborhood representatives into managerial activities in local level. For that purpose, the neighborhood representatives in the center of Burdur province are included in the research. According to the findings, it has been determined that the neighborhood representatives have participated into various activities without experiencing any difficulty, and they have been informed about the services regarding to their neighborhoods, and they have kept close relationship with central and local administrations, and most of them could communicate with local authorities directly. Therefore, it has been concluded that the neighborhood representatives have been influential enough in decision-making mechanisms in local level in Burdur.

  15. A wavelet-based Gaussian method for energy dispersive X-ray fluorescence spectrum

    Directory of Open Access Journals (Sweden)

    Pan Liu

    2017-05-01

    Full Text Available This paper presents a wavelet-based Gaussian method (WGM for the peak intensity estimation of energy dispersive X-ray fluorescence (EDXRF. The relationship between the parameters of Gaussian curve and the wavelet coefficients of Gaussian peak point is firstly established based on the Mexican hat wavelet. It is found that the Gaussian parameters can be accurately calculated by any two wavelet coefficients at the peak point which has to be known. This fact leads to a local Gaussian estimation method for spectral peaks, which estimates the Gaussian parameters based on the detail wavelet coefficients of Gaussian peak point. The proposed method is tested via simulated and measured spectra from an energy X-ray spectrometer, and compared with some existing methods. The results prove that the proposed method can directly estimate the peak intensity of EDXRF free from the background information, and also effectively distinguish overlap peaks in EDXRF spectrum.

  16. Stable Lévy motion with inverse Gaussian subordinator

    Science.gov (United States)

    Kumar, A.; Wyłomańska, A.; Gajda, J.

    2017-09-01

    In this paper we study the stable Lévy motion subordinated by the so-called inverse Gaussian process. This process extends the well known normal inverse Gaussian (NIG) process introduced by Barndorff-Nielsen, which arises by subordinating ordinary Brownian motion (with drift) with inverse Gaussian process. The NIG process found many interesting applications, especially in financial data description. We discuss here the main features of the introduced subordinated process, such as distributional properties, existence of fractional order moments and asymptotic tail behavior. We show the connection of the process with continuous time random walk. Further, the governing fractional partial differential equations for the probability density function is also obtained. Moreover, we discuss the asymptotic distribution of sample mean square displacement, the main tool in detection of anomalous diffusion phenomena (Metzler et al., 2014). In order to apply the stable Lévy motion time-changed by inverse Gaussian subordinator we propose a step-by-step procedure of parameters estimation. At the end, we show how the examined process can be useful to model financial time series.

  17. DISTANCES TO FOUR SOLAR NEIGHBORHOOD ECLIPSING BINARIES FROM ABSOLUTE FLUXES

    International Nuclear Information System (INIS)

    Wilson, R. E.; Van Hamme, W.

    2009-01-01

    Eclipsing binary (EB)-based distances are estimated for four solar neighborhood EBs by means of the Direct Distance Estimation (DDE) algorithm. Results are part of a project to map the solar neighborhood EBs in three dimensions, independently of parallaxes, and provide statistical comparisons between EB and parallax distances. Apart from judgments on adopted temperature and interstellar extinction, DDE's simultaneous light-velocity solutions are essentially objective and work as well for semidetached (SD) and overcontact binaries as for detached systems. Here, we analyze two detached and two SD binaries, all double lined. RS Chamaeleontis is a pre-main-sequence (MS), detached EB with weak δ Scuti variations. WW Aurigae is detached and uncomplicated, except for having high metallicity. RZ Cassiopeiae is SD and has very clear δ Scuti variations and several peculiarities. R Canis Majoris (R CMa) is an apparently simple but historically problematic SD system, also with weak δ Scuti variations. Discussions include solution rules and strategies, weighting, convergence, and third light problems. So far there is no indication of systematic band dependence among the derived distances, so the adopted band-calibration ratios seem consistent. Agreement of EB-based and parallax distances is typically within the overlapped uncertainties, with minor exceptions. We also suggest an explanation for the long-standing undermassiveness problem of R CMa's hotter component, in terms of a fortuitous combination of low metallicity and evolution slightly beyond the MS.

  18. Controllable gaussian-qubit interface for extremal quantum state engineering.

    Science.gov (United States)

    Adesso, Gerardo; Campbell, Steve; Illuminati, Fabrizio; Paternostro, Mauro

    2010-06-18

    We study state engineering through bilinear interactions between two remote qubits and two-mode gaussian light fields. The attainable two-qubit states span the entire physically allowed region in the entanglement-versus-global-purity plane. Two-mode gaussian states with maximal entanglement at fixed global and marginal entropies produce maximally entangled two-qubit states in the corresponding entropic diagram. We show that a small set of parameters characterizing extremally entangled two-mode gaussian states is sufficient to control the engineering of extremally entangled two-qubit states, which can be realized in realistic matter-light scenarios.

  19. Neighborhood fast food restaurants and fast food consumption: A national study

    OpenAIRE

    Richardson, Andrea S; Boone-Heinonen, Janne; Popkin, Barry M; Gordon-Larsen, Penny

    2011-01-01

    Abstract Background Recent studies suggest that neighborhood fast food restaurant availability is related to greater obesity, yet few studies have investigated whether neighborhood fast food restaurant availability promotes fast food consumption. Our aim was to estimate the effect of neighborhood fast food availability on frequency of fast food consumption in a national sample of young adults, a population at high risk for obesity. Methods We used national data from U.S. young adults enrolled...

  20. Primordial non-Gaussian features from DBI Galileon inflation

    International Nuclear Information System (INIS)

    Choudhury, Sayantan; Pal, Supratik

    2015-01-01

    We have studied primordial non-Gaussian features of a model of potential-driven single field DBI Galileon inflation. We have computed the bispectrum from the three-point correlation function considering all possible cross correlations between the scalar and tensor modes of the proposed setup. Further, we have computed the trispectrum from a four-point correlation function considering the contribution from contact interaction, and scalar and graviton exchange diagrams in the in-in picture. Finally we have obtained the non-Gaussian consistency conditions from the four-point correlator, which results in partial violation of the Suyama-Yamaguchi four-point consistency relation. This further leads to the conclusion that sufficient primordial non-Gaussianities can be obtained from DBI Galileon inflation. (orig.)