Capturing the two dimensions of residential segregation at the neighborhood level for health research

Two conceptual and methodological foundations of segregation studies are that (i) segregation involves more than one group, and (ii) segregation measures need to quantify how different population groups are distributed across space. Therefore, percentage of population belonging to a group is not an appropriate measure of segregation because it does not describe how populations are spread across different areal units or neighborhoods. In principle, evenness and isolation are the two distinct dimensions of segregation that capture the spatial patterns of population groups. To portray people’s daily environment more accurately, segregation measures need to account for the spatial relationships between areal units and to reflect the situations at the neighborhood scale. For these reasons, the use of local spatial entropy-based diversity index (SHi) and local spatial isolation index (Si) to capture the evenness and isolation dimensions of segregation, respectively, are preferable. However, these two local spatial segregation indexes have rarely been incorporated into health research. Rather ineffective and insufficient segregation measures have been used in previous studies. Hence, this paper empirically demonstrates how the two measures can reflect the two distinct dimensions of segregation at the neighborhood level, and argues conceptually and set the stage for their future use to effectively and meaningfully examine the relationships between residential segregation and health.published_or_final_versio

Mapping American community survey data

Maps are a frequently used tool to portray the Census Bureau’s data and highlight spatial patterns that provide context and significance for the characteristics displayed. Maps provide visually what tables and other graphics cannot: a picture of the data, their distribution over geographic areas, and a means for interpreting the data shown by color, symbology, or explanation provided as annotations or as part of the map legend. The value of maps in enhancing an understanding of census data is well established as demonstrated by their frequent use in the media following the release of census data products. Mapping census data is common throughout government, academia, and the private sector. Casual users of maps of statistical data may not look past what is interesting visually to analyze the underlying data that a map depicts. However, that does not absolve the mapmaker of the responsibility for informing users of the statistical qualities associated with the mapped values. The Census Bureau set new standards for communicating the statistical qualities of estimates from the American Community Survey (ACS) by including information on the level of sampling error (specifically, margins of error) associated with every ACS estimate. Now, efforts are underway to develop an operational tool that will make it possible for geographic information systems (GIS) users to communicate this information through map products as well.published_or_final_versio

Fast and robust generation of city scale urban ground plan

Since the introduction of the concept of Digital Earth, almost every major international city has been re-constructed in the virtual world. A large volume of geometric models describing urban objects has become freely available in public domain via software like Google Earth. Although mostly created for visualization, these urban models can benefit many applications beyond visualization including video games, city scale evacuation plan, traffic simulation and earth phenomenon simulations. However, these urban models are mostly loosely structured and implicitly defined and require tedious manual preparation that usually take weeks if not months before they can be used. In this paper, we present a framework that produces well-defined ground plans from these urban models, an important step in the preparation process. Designing algorithms that can robustly and efficiently handle unstructured urban models at city scale is the main technical challenge. In this work, we show both theoretically and empirically that our method is resolution complete, efficient and numerically stable. Based on our review of the related work, we believe this is the first work that attempts to create urban ground plans automatically from 3D architectural meshes at city level. With the goal of providing greater benefit beyond visualization from this large volume of urban models, our initial results are encouraging.published_or_final_versio

Impacts of Scale on Geographic Analysis of Health Data: An Example of Obesity Prevalence

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A Semi-analytical Model for Remote Sensing Retrieval of Suspended Sediment Concentration in the Gulf of Bohai, China

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Determination Of The Effective Anisotropy Constant Of Cofe2o4 Nanoparticles Through The T-dependence Of The Coercive Field

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We present a systematic study of the coercive field of CoFe2O4-SiO2 nanocomposites. The samples were prepared via the sol-gel method by using the Tetraethyl Orthosilicate as starting reagent. Results of X-ray diffraction, transmission electron microscopy, and X-ray fluorescence confirm the dispersion of the magnetic nanoparticles inside the silica matrix. In addition, the shift in the maximum of Zero-Field-Cooled curves observed by varying the weight ratio of CoFe2O4 nanoparticles to the precursor of silica is consistent with the increasing of average interparticle distances. Because our samples present a particle size distribution, we have used a generalized model which takes account such parameter to fit the experimental data of coercive field extracted from the magnetization curves as a function of applied field. Unlike most of the coercive field results reported in the literature for this material, the use of this model provided a successful description of the temperature dependence of the coercive field of CoFe2O4 nanoparticles in a wide temperature range. Surprisingly, we have observed the decreasing of the nanoparticles anisotropy constant in comparison to the bulk value expected for the material. We believe that this can be interpreted as due to both the migration of the Co2+ from octahedral to tetrahedral sites. (C) 2016 AIP Publishing LLC.119CAPESCNPqFAPITECCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Quantifying beliefs regarding telehealth: Development of the Whole Systems Demonstrator Service User Technology Acceptability Questionnaire

Introduction: Telehealth (TH) is a potential solution to the increased incidence of chronic illness in an ageing population. The extent to which older people and users with chronic conditions accept and adhere to using assistive technologies is a potential barrier to mainstreaming the service. This study reports the development and validation of the Whole Systems Demonstrator (WSD) Service User Technology Acceptability Questionnaire (SUTAQ). / Methods: Questionnaires measuring the acceptability of TH, quality of life, well-being and psychological processes were completed by 478 users of TH. The 22 acceptability items were subject to principal components analysis (PCA) to determine sub-scales. Scale scores, relationships between scales and other patient-reported outcome measures (PROMs), and group differences on scales were utilised to check the reliability and validity of the measure. / Results: PCAs of SUTAQ items produced six TH acceptability scales: enhanced care, increased accessibility, privacy and discomfort, care personnel concerns, kit as substitution and satisfaction. Significant correlations within these beliefs and between these scales and additional PROMs were coherent, and the SUTAQ sub-scales were able to predict those more likely to refuse TH. / Discussion: The SUTAQ is an instrument that can be used to measure user beliefs about the acceptability of TH, and has the ability to discriminate between groups and predict individual differences in beliefs and behaviour. Measuring acceptability beliefs of TH users can provide valuable information to direct and target provision of services to increase uptake and maintain use of TH

The Threshold Bias Model: A Mathematical Model for the Nomothetic Approach of Suicide

Comparative and predictive analyses of suicide data from different countries are difficult to perform due to varying approaches and the lack of comparative parameters.A simple model (the Threshold Bias Model) was tested for comparative and predictive analyses of suicide rates by age. The model comprises of a six parameter distribution that was applied to the USA suicide rates by age for the years 2001 and 2002. Posteriorly, linear extrapolations are performed of the parameter values previously obtained for these years in order to estimate the values corresponding to the year 2003. The calculated distributions agreed reasonably well with the aggregate data. The model was also used to determine the age above which suicide rates become statistically observable in USA, Brazil and Sri Lanka.The Threshold Bias Model has considerable potential applications in demographic studies of suicide. Moreover, since the model can be used to predict the evolution of suicide rates based on information extracted from past data, it will be of great interest to suicidologists and other researchers in the field of mental health

Seismic reflection images of a near-axis melt sill within the lower crust at the Juan de Fuca ridge

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature 460 (2009): 89-93, doi:10.1038/nature08095.The oceanic crust extends over two thirds of the Earth’s solid surface and is generated along mid-ocean ridges from melts derived from the upwelling mantle. The upper and mid crust are constructed by dyking and seafloor eruptions originating from magma accumulated in mid-crustal lenses at the spreading axis, but the style of accretion of the lower oceanic crust is actively debated. Models based on geological and petrological data from ophiolites propose that the lower oceanic crust is accreted from melt sills intruded at multiple levels between the Moho transition zone (MTZ) and the mid-crustal lens, consistent with geophysical studies that suggest the presence of melt within the lower crust. However, seismic images of molten sills within the lower crust have been elusive. To date only seismic reflections from mid-crustal melt lenses and sills within the MTZ have been described, suggesting that melt is efficiently transported through the lower crust. Here we report deep crustal seismic reflections off the southern Juan de Fuca Ridge that we interpret as originating from a molten sill presently accreting the lower oceanic crust. The sill sits 5-6 km beneath the seafloor and 850-900 m above the MTZ, and it is located 1.4-3.2 km off thespreading axis. Our results provide evidence for the existence of low permeability barriers to melt migration within the lower section of modern oceanic crust forming at intermediate-to-fast spreading rates, as inferred from ophiolite studies.This research was supported by grants form the US NSF