WorldWideScience

Sample records for methods population based

  1. Population based ranking of frameless CT-MRI registration methods

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    Opposits, Gabor; Kis, Sandor A.; Tron, Lajos; Emri, Miklos [Debrecen Univ. (Hungary). Dept. of Nuclear Medicine; Berenyi, Ervin [Debrecen Univ. (Hungary). Dept. of Biomedical Laboratory and Imaging Science; Takacs, Endre [Rotating Gamma Ltd., Debrecen (Hungary); Dobai, Jozsef G.; Bognar, Laszlo [Debrecen Univ., Medical Center (Hungary). Dept. of Neurosurgery; Szuecs, Bernadett [ScanoMed Ltd., Debrecen (Hungary)

    2015-07-01

    Clinical practice often requires simultaneous information obtained by two different imaging modalities. Registration algorithms are commonly used for this purpose. Automated procedures are very helpful in cases when the same kind of registration has to be performed on images of a high number of subjects. Radiotherapists would prefer to use the best automated method to assist therapy planning, however there are not accepted procedures for ranking the different registration algorithms. We were interested in developing a method to measure the population level performance of CT-MRI registration algorithms by a parameter of values in the [0,1] interval. Pairs of CT and MRI images were collected from 1051 subjects. Results of an automated registration were corrected manually until a radiologist and a neurosurgeon expert both accepted the result as good. This way 1051 registered MRI images were produced by the same pair of experts to be used as gold standards for the evaluation of the performance of other registration algorithms. Pearson correlation coefficient, mutual information, normalized mutual information, Kullback-Leibler divergence, L{sub 1} norm and square L{sub 2} norm (dis)similarity measures were tested for sensitivity to indicate the extent of (dis)similarity of a pair of individual mismatched images. The square Hellinger distance proved suitable to grade the performance of registration algorithms at population level providing the developers with a valuable tool to rank algorithms. The developed procedure provides an objective method to find the registration algorithm performing the best on the population level out of newly constructed or available preselected ones.

  2. Consequences of population topology for studying gene flow using link-based landscape genetic methods.

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    van Strien, Maarten J

    2017-07-01

    Many landscape genetic studies aim to determine the effect of landscape on gene flow between populations. These studies frequently employ link-based methods that relate pairwise measures of historical gene flow to measures of the landscape and the geographical distance between populations. However, apart from landscape and distance, there is a third important factor that can influence historical gene flow, that is, population topology (i.e., the arrangement of populations throughout a landscape). As the population topology is determined in part by the landscape configuration, I argue that it should play a more prominent role in landscape genetics. Making use of existing literature and theoretical examples, I discuss how population topology can influence results in landscape genetic studies and how it can be taken into account to improve the accuracy of these results. In support of my arguments, I have performed a literature review of landscape genetic studies published during the first half of 2015 as well as several computer simulations of gene flow between populations. First, I argue why one should carefully consider which population pairs should be included in link-based analyses. Second, I discuss several ways in which the population topology can be incorporated in response and explanatory variables. Third, I outline why it is important to sample populations in such a way that a good representation of the population topology is obtained. Fourth, I discuss how statistical testing for link-based approaches could be influenced by the population topology. I conclude the article with six recommendations geared toward better incorporating population topology in link-based landscape genetic studies.

  3. An Improved Real-Coded Population-Based Extremal Optimization Method for Continuous Unconstrained Optimization Problems

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    Guo-Qiang Zeng

    2014-01-01

    Full Text Available As a novel evolutionary optimization method, extremal optimization (EO has been successfully applied to a variety of combinatorial optimization problems. However, the applications of EO in continuous optimization problems are relatively rare. This paper proposes an improved real-coded population-based EO method (IRPEO for continuous unconstrained optimization problems. The key operations of IRPEO include generation of real-coded random initial population, evaluation of individual and population fitness, selection of bad elements according to power-law probability distribution, generation of new population based on uniform random mutation, and updating the population by accepting the new population unconditionally. The experimental results on 10 benchmark test functions with the dimension N=30 have shown that IRPEO is competitive or even better than the recently reported various genetic algorithm (GA versions with different mutation operations in terms of simplicity, effectiveness, and efficiency. Furthermore, the superiority of IRPEO to other evolutionary algorithms such as original population-based EO, particle swarm optimization (PSO, and the hybrid PSO-EO is also demonstrated by the experimental results on some benchmark functions.

  4. The evaluation of a population based diffusion tensor image atlas using a ground truth method

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    Van Hecke, Wim; Leemans, Alexander; D'Agostino, Emiliano; De Backer, Steve; Vandervliet, Evert; Parizel, Paul M.; Sijbers, Jan

    2008-03-01

    Purpose: Voxel based morphometry (VBM) is increasingly being used to detect diffusion tensor (DT) image abnormalities in patients for different pathologies. An important requisite for these VBM studies is the use of a high-dimensional, non-rigid coregistration technique, which is able to align both the spatial and the orientational information. Recent studies furthermore indicate that high-dimensional DT information should be included during coregistration for an optimal alignment. In this context, a population based DTI atlas is created that preserves the orientational DT information robustly and contains a minimal bias towards any specific individual data set. Methods: A ground truth evaluation method is developed using a single subject DT image that is deformed with 20 deformation fields. Thereafter, an atlas is constructed based on these 20 resulting images. Thereby, the non-rigid coregistration algorithm is based on a viscous fluid model and on mutual information. The fractional anisotropy (FA) maps as well as the DT elements are used as DT image information during the coregistration algorithm, in order to minimize the orientational alignment inaccuracies. Results: The population based DT atlas is compared with the ground truth image using accuracy and precision measures of spatial and orientational dependent metrics. Results indicate that the population based atlas preserves the orientational information in a robust way. Conclusion: A subject independent population based DT atlas is constructed and evaluated with a ground truth method. This atlas contains all available orientational information and can be used in future VBM studies as a reference system.

  5. Methods of Suicide among Cancer Patients: A Nationwide Population-Based Study

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    Chung, Kuo-Hsuan; Lin, Herng-Ching

    2010-01-01

    A 3-year nationwide population-based data set was used to explore methods of suicide (violent vs. nonviolent) and possible contributing factors among cancer patients in Taiwan. A total of 1,065 cancer inpatients who committed suicide were included as our study sample. The regression shows that those who had genitourinary cancer were 0.55 times (p…

  6. Comparing methods of targeting obesity interventions in populations: An agent-based simulation.

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    Beheshti, Rahmatollah; Jalalpour, Mehdi; Glass, Thomas A

    2017-12-01

    Social networks as well as neighborhood environments have been shown to effect obesity-related behaviors including energy intake and physical activity. Accordingly, harnessing social networks to improve targeting of obesity interventions may be promising to the extent this leads to social multiplier effects and wider diffusion of intervention impact on populations. However, the literature evaluating network-based interventions has been inconsistent. Computational methods like agent-based models (ABM) provide researchers with tools to experiment in a simulated environment. We develop an ABM to compare conventional targeting methods (random selection, based on individual obesity risk, and vulnerable areas) with network-based targeting methods. We adapt a previously published and validated model of network diffusion of obesity-related behavior. We then build social networks among agents using a more realistic approach. We calibrate our model first against national-level data. Our results show that network-based targeting may lead to greater population impact. We also present a new targeting method that outperforms other methods in terms of intervention effectiveness at the population level.

  7. Method for mapping population-based case-control studies: an application using generalized additive models

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    Aschengrau Ann

    2006-06-01

    Full Text Available Abstract Background Mapping spatial distributions of disease occurrence and risk can serve as a useful tool for identifying exposures of public health concern. Disease registry data are often mapped by town or county of diagnosis and contain limited data on covariates. These maps often possess poor spatial resolution, the potential for spatial confounding, and the inability to consider latency. Population-based case-control studies can provide detailed information on residential history and covariates. Results Generalized additive models (GAMs provide a useful framework for mapping point-based epidemiologic data. Smoothing on location while controlling for covariates produces adjusted maps. We generate maps of odds ratios using the entire study area as a reference. We smooth using a locally weighted regression smoother (loess, a method that combines the advantages of nearest neighbor and kernel methods. We choose an optimal degree of smoothing by minimizing Akaike's Information Criterion. We use a deviance-based test to assess the overall importance of location in the model and pointwise permutation tests to locate regions of significantly increased or decreased risk. The method is illustrated with synthetic data and data from a population-based case-control study, using S-Plus and ArcView software. Conclusion Our goal is to develop practical methods for mapping population-based case-control and cohort studies. The method described here performs well for our synthetic data, reproducing important features of the data and adequately controlling the covariate. When applied to the population-based case-control data set, the method suggests spatial confounding and identifies statistically significant areas of increased and decreased odds ratios.

  8. Validity and feasibility of a satellite imagery-based method for rapid estimation of displaced populations.

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    Checchi, Francesco; Stewart, Barclay T; Palmer, Jennifer J; Grundy, Chris

    2013-01-23

    Estimating the size of forcibly displaced populations is key to documenting their plight and allocating sufficient resources to their assistance, but is often not done, particularly during the acute phase of displacement, due to methodological challenges and inaccessibility. In this study, we explored the potential use of very high resolution satellite imagery to remotely estimate forcibly displaced populations. Our method consisted of multiplying (i) manual counts of assumed residential structures on a satellite image and (ii) estimates of the mean number of people per structure (structure occupancy) obtained from publicly available reports. We computed population estimates for 11 sites in Bangladesh, Chad, Democratic Republic of Congo, Ethiopia, Haiti, Kenya and Mozambique (six refugee camps, three internally displaced persons' camps and two urban neighbourhoods with a mixture of residents and displaced) ranging in population from 1,969 to 90,547, and compared these to "gold standard" reference population figures from census or other robust methods. Structure counts by independent analysts were reasonably consistent. Between one and 11 occupancy reports were available per site and most of these reported people per household rather than per structure. The imagery-based method had a precision relative to reference population figures of layout. For each site, estimates were produced in 2-5 working person-days. In settings with clearly distinguishable individual structures, the remote, imagery-based method had reasonable accuracy for the purposes of rapid estimation, was simple and quick to implement, and would likely perform better in more current application. However, it may have insurmountable limitations in settings featuring connected buildings or shelters, a complex pattern of roofs and multi-level buildings. Based on these results, we discuss possible ways forward for the method's development.

  9. Use of various contraceptive methods and time of conception in a community-based population.

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    Kaplan, Boris; Nahum, Ravit; Yairi, Yael; Hirsch, Michael; Pardo, Josef; Yogev, Yariv; Orvieto, Raoul

    2005-11-01

    To investigate the association between method of contraception and time to conception in a normal community-based population. Prospective, cross-sectional, survey. Large comprehensive ambulatory women's health center. One thousand pregnant women at their first prenatal obstetrics visit were asked to complete a self-report questionnaire. The return to fertility was analyzed by type of contraceptive method, duration of use, and other sociodemographic variables. Response rate was 80% (n=798). Mean age of the patients was 29.9+/-5 years. Seventy-five percent had used a contraceptive before trying to conceive: 80% oral contraceptives, 8% intrauterine device, and 7% barrier methods. Eighty-six percent conceived spontaneously. Contraceptive users had a significantly higher conception rate than nonusers in the first 3 months from their first attempt at pregnancy. Type of contraception was significantly correlated with time to conception. Pregnancy rates within 6 months of the first attempt was 60% for oral contraceptive users compared to 70 and 81% for the intrauterine device and barrier method groups, respectively. There was no correlation between time to conception and parity or duration of contraceptive use. Other factors found to be significantly related to time to conception were older age of both partners and higher body mass index. Contraception use before a planned pregnancy does not appear to affect ease of conception. Type of method used, although not duration of use, may influence the time required to conceive.

  10. Differential estimates of southern flying squirrel (Glaucomys volans) population structure based on capture method

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    Kevin S. Laves; Susan C. Loeb

    2005-01-01

    It is commonly assumed that population estimates derived from trapping small mammals are accurate and unbiased or that estimates derived from different capture methods are comparable. We captured southern flying squirrels (Glaucmrtys volam) using two methods to study their effect on red-cockaded woodpecker (Picoides bumah) reproductive success. Southern flying...

  11. Adaptive list sequential sampling method for population-based observational studies

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    Hof, Michel H.; Ravelli, Anita C. J.; Zwinderman, Aeilko H.

    2014-01-01

    In population-based observational studies, non-participation and delayed response to the invitation to participate are complications that often arise during the recruitment of a sample. When both are not properly dealt with, the composition of the sample can be different from the desired

  12. Population-based cancer survival in the United States: Data, quality control, and statistical methods.

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    Allemani, Claudia; Harewood, Rhea; Johnson, Christopher J; Carreira, Helena; Spika, Devon; Bonaventure, Audrey; Ward, Kevin; Weir, Hannah K; Coleman, Michel P

    2017-12-15

    Robust comparisons of population-based cancer survival estimates require tight adherence to the study protocol, standardized quality control, appropriate life tables of background mortality, and centralized analysis. The CONCORD program established worldwide surveillance of population-based cancer survival in 2015, analyzing individual data on 26 million patients (including 10 million US patients) diagnosed between 1995 and 2009 with 1 of 10 common malignancies. In this Cancer supplement, we analyzed data from 37 state cancer registries that participated in the second cycle of the CONCORD program (CONCORD-2), covering approximately 80% of the US population. Data quality checks were performed in 3 consecutive phases: protocol adherence, exclusions, and editorial checks. One-, 3-, and 5-year age-standardized net survival was estimated using the Pohar Perme estimator and state- and race-specific life tables of all-cause mortality for each year. The cohort approach was adopted for patients diagnosed between 2001 and 2003, and the complete approach for patients diagnosed between 2004 and 2009. Articles in this supplement report population coverage, data quality indicators, and age-standardized 5-year net survival by state, race, and stage at diagnosis. Examples of tables, bar charts, and funnel plots are provided in this article. Population-based cancer survival is a key measure of the overall effectiveness of services in providing equitable health care. The high quality of US cancer registry data, 80% population coverage, and use of an unbiased net survival estimator ensure that the survival trends reported in this supplement are robustly comparable by race and state. The results can be used by policymakers to identify and address inequities in cancer survival in each state and for the United States nationally. Cancer 2017;123:4982-93. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Published 2017. This article is a U

  13. A two-stage cluster sampling method using gridded population data, a GIS, and Google EarthTM imagery in a population-based mortality survey in Iraq

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    Galway LP

    2012-04-01

    Full Text Available Abstract Background Mortality estimates can measure and monitor the impacts of conflict on a population, guide humanitarian efforts, and help to better understand the public health impacts of conflict. Vital statistics registration and surveillance systems are rarely functional in conflict settings, posing a challenge of estimating mortality using retrospective population-based surveys. Results We present a two-stage cluster sampling method for application in population-based mortality surveys. The sampling method utilizes gridded population data and a geographic information system (GIS to select clusters in the first sampling stage and Google Earth TM imagery and sampling grids to select households in the second sampling stage. The sampling method is implemented in a household mortality study in Iraq in 2011. Factors affecting feasibility and methodological quality are described. Conclusion Sampling is a challenge in retrospective population-based mortality studies and alternatives that improve on the conventional approaches are needed. The sampling strategy presented here was designed to generate a representative sample of the Iraqi population while reducing the potential for bias and considering the context specific challenges of the study setting. This sampling strategy, or variations on it, are adaptable and should be considered and tested in other conflict settings.

  14. A new method for studying population genetics of cyst nematodes based on Pool-Seq and genomewide allele frequency analysis.

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    Mimee, Benjamin; Duceppe, Marc-Olivier; Véronneau, Pierre-Yves; Lafond-Lapalme, Joël; Jean, Martine; Belzile, François; Bélair, Guy

    2015-11-01

    Cyst nematodes are important agricultural pests responsible for billions of dollars of losses each year. Plant resistance is the most effective management tool, but it requires a close monitoring of population genetics. Current technologies for pathotyping and genotyping cyst nematodes are time-consuming, expensive and imprecise. In this study, we capitalized on the reproduction mode of cyst nematodes to develop a simple population genetic analysis pipeline based on genotyping-by-sequencing and Pool-Seq. This method yielded thousands of SNPs and allowed us to study the relationships between populations of different origins or pathotypes. Validation of the method on well-characterized populations also demonstrated that it was a powerful and accurate tool for population genetics. The genomewide allele frequencies of 23 populations of golden nematode, from nine countries and representing the five known pathotypes, were compared. A clear separation of the pathotypes and fine genetic relationships between and among global populations were obtained using this method. In addition to being powerful, this tool has proven to be very time- and cost-efficient and could be applied to other cyst nematode species. © 2015 Her Majesty the Queen in Right of Canada Molecular Ecology Resources © 2015 John Wiley & Sons Ltd Reproduced with the permission of the Minister of Agriculture and Agri-food.

  15. Childhood disability in Malawi: a population based assessment using the key informant method.

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    Tataryn, Myroslava; Polack, Sarah; Chokotho, Linda; Mulwafu, Wakisa; Kayange, Petros; Banks, Lena Morgon; Noe, Christiane; Lavy, Chris; Kuper, Hannah

    2017-11-28

    Epidemiological data on childhood disability are lacking in Low and Middle Income countries (LMICs) such as Malawi, hampering effective service planning and advocacy. The Key Informant Method (KIM) is an innovative, cost-effective method for generating population data on the prevalence and causes of impairment in children. The aim of this study was to use the Key Informant Method to estimate the prevalence of moderate/severe, hearing, vision and physical impairments, intellectual impairments and epilepsy in children in two districts in Malawi and to estimate the associated need for rehabilitation and other services. Five hundred key informants (KIs) were trained to identify children in their communities who may have the impairment types included in this study. Identified children were invited to attend a screening camp where they underwent assessment by medical professionals for moderate/severe hearing, vision and physical impairments, intellectual impairments and epilepsy. Approximately 15,000 children were identified by KIs as potentially having an impairment of whom 7220 (48%) attended a screening camp. The estimated prevalence of impairments/epilepsy was 17.3/1000 children (95% CI: 16.9-17.7). Physical impairment (39%) was the commonest impairment type followed by hearing impairment (27%), intellectual impairment (26%), epilepsy (22%) and vision impairment (4%). Approximately 2100 children per million population could benefit from physiotherapy and occupational therapy and 300 per million are in need of a wheelchair. An estimated 1800 children per million population have hearing impairment caused by conditions that could be prevented or treated through basic primary ear care. Corneal opacity was the leading cause of vision impairment. Only 50% of children with suspected epilepsy were receiving medication. The majority (73%) of children were attending school, but attendance varied by impairment type and was lowest among children with multiple impairments (38

  16. A Comparison of Internet-Based Participant Recruitment Methods: Engaging the Hidden Population of Cannabis Users in Research

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    Elizabeth Clare Temple

    2011-01-01

    Full Text Available While a growing number of researchers are embracing Internet-based data collection methods, the adoption of Internet-based recruitment methods has been relatively slow. This may be because little is known regarding the relative strengths and weaknesses of different methods of Internet-based participant recruitment, nor how these different recruitment strategies impact on the data collected. These issues are addressed in this article with reference to a study comparing the effectiveness of three Internet-based strategies in recruiting cannabis users for an online study. Consideration of the recruitment data leads us to recommend that researchers use multipronged Internet-based recruitment campaigns with appropriately detailed recruitment messages tailored to the population of interest and located carefully to ensure they reach the intended audience. Further, we suggest that building rapport directly with potential participants, or utilising derived rapport and implicit endorsements, is an important aspect of successful Internet-based participant recruitment strategies.

  17. Statistical Methods for Population Genetic Inference Based on Low-Depth Sequencing Data from Modern and Ancient DNA

    DEFF Research Database (Denmark)

    Korneliussen, Thorfinn Sand

    Due to the recent advances in DNA sequencing technology genomic data are being generated at an unprecedented rate and we are gaining access to entire genomes at population level. The technology does, however, not give direct access to the genetic variation and the many levels of preprocessing...... that is required before being able to make inferences from the data introduces multiple levels of uncertainty, especially for low-depth data. Therefore methods that take into account the inherent uncertainty are needed for being able to make robust inferences in the downstream analysis of such data. This poses...... a problem for a range of key summary statistics within populations genetics where existing methods are based on the assumption that the true genotypes are known. Motivated by this I present: 1) a new method for the estimation of relatedness between pairs of individuals, 2) a new method for estimating...

  18. Feeding methods, sleep arrangement, and infant sleep patterns: a Chinese population-based study.

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    Huang, Xiao-Na; Wang, Hui-Shan; Chang, Jen-Jen; Wang, Lin-Hong; Liu, Xi-Cheng; Jiang, Jing-Xiong; An, Lin

    2016-02-01

    Findings from prior research into the effect of feeding methods on infant sleep are inconsistent. The objectives of this study were to examine infants' sleep patterns by feeding methods and sleep arrangement from birth to eight months old. This longitudinal cohort study enrolled 524 pregnant women at 34-41 weeks of gestation and their infants after delivery in 2006 and followed up until eight months postpartum. The study subjects were recruited from nine women and children hospitals in nine cities in China (Beijing, Chongqing, Wuhan, Changsha, Nanning, Xiamen, Xi'an, Jinan, and Hailin). Participating infants were followed up weekly during the first month and monthly from the second to the eighth month after birth. Twenty-four hour sleep diaries recording infants' sleeping and feeding methods were administered based on caregiver's self-report. Multivariable mixed growth curve models were fitted to estimate the effects of feeding methods and sleep arrangement on infants' sleep patterns over time, controlling for maternal and paternal age, maternal and paternal education level, household income, supplementation of complementary food, and infant birth weight and length. Exclusively formula fed infants had the greatest sleep percentage/24 h, followed by exclusively breast milk fed infants and partially breast milk fed infants (Psleep percentage and night waking frequency between exclusively formula and exclusively breast milk fed infants weakened over time as infants developed. In addition, compared to infants with bed-sharing sleep arrangement, those with room sharing sleep arrangement had greater daytime and 24-hour infant sleep percentage, whereas those with sleeping alone sleep arrangement had greater nighttime sleep percentage. Our data based on caregiver's self-report suggested that partial breastfeeding and bed-sharing may be associated with less sleep in infants. Health care professionals need to work with parents of newborns to develop coping strategies that

  19. ANFIS Based Time Series Prediction Method of Bank Cash Flow Optimized by Adaptive Population Activity PSO Algorithm

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    Jie-Sheng Wang

    2015-06-01

    Full Text Available In order to improve the accuracy and real-time of all kinds of information in the cash business, and solve the problem which accuracy and stability is not high of the data linkage between cash inventory forecasting and cash management information in the commercial bank, a hybrid learning algorithm is proposed based on adaptive population activity particle swarm optimization (APAPSO algorithm combined with the least squares method (LMS to optimize the adaptive network-based fuzzy inference system (ANFIS model parameters. Through the introduction of metric function of population diversity to ensure the diversity of population and adaptive changes in inertia weight and learning factors, the optimization ability of the particle swarm optimization (PSO algorithm is improved, which avoids the premature convergence problem of the PSO algorithm. The simulation comparison experiments are carried out with BP-LMS algorithm and standard PSO-LMS by adopting real commercial banks’ cash flow data to verify the effectiveness of the proposed time series prediction of bank cash flow based on improved PSO-ANFIS optimization method. Simulation results show that the optimization speed is faster and the prediction accuracy is higher.

  20. A community-based mixed methods approach to developing behavioural health interventions among indigenous adolescent populations

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    Tingey, L.L.

    2016-01-01

    Native American and indigenous populations experience the greatest behavioural health disparities in the world. A constellation of factors impacting Native American Tribes contributes to high rates and co-morbidity of mental health disorders, substance use and sexually transmitted infection (STI),

  1. Methods and background characteristics of the TOHNN study: a population-based study of oral health conditions in northern Norway

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    Holde, Gro Eirin; Oscarson, Nils; Tillberg, Anders; Marstrander, Peter; Jönsson, Birgitta

    2016-01-01

    Objectives The aim of the Tromstannen – Oral Health in Northern Norway (TOHNN) study was to investigate oral health and dental-related diseases in an adult population. This article provides an overview of the background of the study and a description of the sample characteristics and methods employed in data collection. Study design Cross-sectional population-based study including a questionnaire and clinical dental examination. Methods A randomly selected sample of 2,909 individuals (20–79 years old) drawn from the population register was invited to participate in the study. The data were collected between October 2013 and November 2014 in Troms County in northern Norway. The questionnaire focused on oral health-related behaviours and attitudes, oral health-related quality of life, sense of coherence, dental anxiety and symptoms from the temporomandibular joint. The dental examinations, including radiographs, were conducted by 11 dental teams in 5 dental offices. The examination comprised of registration of dental caries, full mouth periodontal status, temporomandibular disorders, mucosal lesions and height and weight. The participants were grouped by age (20–34, 35–49, 50–64 and 65–79) and ethnicity (Norwegian, Sámi, other European and other world). Results From the original sample of 2,909 individuals, 1,986 (68.3%) people participated, of whom 1,019 (51.3%) were women. The highest attendance rate was among women 20–34 years old (80.3%) and the lowest in the oldest age group of women (55.4%). There was no difference in response rate between rural and urban areas. There was a positive correlation between population size and household gross income (p population in Troms County. Due to the high participation rate, generalization both nationally and to the circumpolar area ought to be possible. PMID:26900910

  2. IDENTIFYING HIGH-RISK POPULATIONS OF TUBERCULOSIS USING ENVIRONMENTAL FACTORS AND GIS BASED MULTI-CRITERIA DECISION MAKING METHOD

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    A. R. Abdul Rasam

    2016-09-01

    Full Text Available Development of an innovative method to enhance the detection of tuberculosis (TB in Malaysia is the latest agenda of the Ministry of Health. Therefore, a geographical information system (GIS based index model is proposed as an alternative method for defining potential high-risk areas of local TB cases at Section U19, Shah Alam. It is adopted a spatial multi-criteria decision making (MCDM method for ranking environmental risk factors of the disease in a standardised five-score scale. Scale 1 and 5 illustrate the lowest and the highest risk of the TB spread respectively, while scale from 3 to 5 is included as a potential risk level. These standardised scale values are then combined with expert normalised weights (0 to 1 to calculate the overall index values and produce a TB ranked map using a GIS overlay analysis and weighted linear combination. It is discovered that 71.43% of the Section is potential as TB high risk areas particularly at urban and densely populated settings. This predictive result is also reliable with the current real cases in 2015 by 76.00% accuracy. A GIS based MCDM method has demonstrated analytical capabilities in targeting high-risk spots and TB surveillance monitoring system of the country, but the result could be strengthened by applying other uncertainty assessment method.

  3. Regression toward the mean – a detection method for unknown population mean based on Mee and Chua's algorithm

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    Lüdtke Rainer

    2008-08-01

    Full Text Available Abstract Background Regression to the mean (RTM occurs in situations of repeated measurements when extreme values are followed by measurements in the same subjects that are closer to the mean of the basic population. In uncontrolled studies such changes are likely to be interpreted as a real treatment effect. Methods Several statistical approaches have been developed to analyse such situations, including the algorithm of Mee and Chua which assumes a known population mean μ. We extend this approach to a situation where μ is unknown and suggest to vary it systematically over a range of reasonable values. Using differential calculus we provide formulas to estimate the range of μ where treatment effects are likely to occur when RTM is present. Results We successfully applied our method to three real world examples denoting situations when (a no treatment effect can be confirmed regardless which μ is true, (b when a treatment effect must be assumed independent from the true μ and (c in the appraisal of results of uncontrolled studies. Conclusion Our method can be used to separate the wheat from the chaff in situations, when one has to interpret the results of uncontrolled studies. In meta-analysis, health-technology reports or systematic reviews this approach may be helpful to clarify the evidence given from uncontrolled observational studies.

  4. Nasopharyngeal Epstein-Barr Virus Load: An Efficient Supplementary Method for Population-Based Nasopharyngeal Carcinoma Screening.

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    Yufeng Chen

    Full Text Available Serological detection of Epstein-Barr virus (EBV antibodies is frequently used in nasopharyngeal carcinoma (NPC mass screening. However, the large number of seropositive subjects who require close follow-up is still a big burden. The present study aimed to detect the nasopharyngeal EBV load in a high-risk population seropositive for antibodies against EBV, as well as to examine whether assay for nasopharyngeal EBV DNA load might reduce the number of high-risk subjects for follow-up and improve early detection of NPC. A prospective and population-based cohort study was conducted in southern China from 2006 through 2013. Among 22,186 participants, 1045 subjects with serum immunoglobulin A (IgA antibodies against viral capsid antigen (VCA titers ≥ 1:5 were defined as high-risk group, and were then followed-up for NPC occurrence. Qualified nasopharyngeal swab specimens were available from 905 participants and used for quantitative PCR assay. Our study revealed that 89% (802/905 subjects showed positive EBV DNA in nasopharyngeal swab. The nasopharyngeal EBV load in females was higher than that in males. The nasopharyngeal EBV load increased with increasing serum VCA/IgA titers. Eight cases of newly diagnosed NPC showed an extremely elevated EBV load, and 87.5% (7 of 8 patients were early-stage NPCs. The EBV loads of 8 NPCs were significantly higher than those of 897 NPC-free subjects (mean, 2.8 × 10(6 copies/swab [range 4.8 × 10(4-1.1 × 10(8] vs. 5.6 × 10(3 [range 0-3.8 × 10(6]. Using mean EBV load in NPC-free population plus two standard deviations as cut-off value, a higher diagnostic performance was obtained for EBV load test than serum VCA/IgA test (area under ROC, 0.980 vs 0.895. In conclusion, in a prospective and population-based study we demonstrated that an additional assay of EBV load in the nasopharynx among high-risk individuals may reduce the number of subjects needed to be closely followed up and could serve as part of a NPC

  5. The population genomics of archaeological transition in west Iberia: Investigation of ancient substructure using imputation and haplotype-based methods.

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    Rui Martiniano

    2017-07-01

    Full Text Available We analyse new genomic data (0.05-2.95x from 14 ancient individuals from Portugal distributed from the Middle Neolithic (4200-3500 BC to the Middle Bronze Age (1740-1430 BC and impute genomewide diploid genotypes in these together with published ancient Eurasians. While discontinuity is evident in the transition to agriculture across the region, sensitive haplotype-based analyses suggest a significant degree of local hunter-gatherer contribution to later Iberian Neolithic populations. A more subtle genetic influx is also apparent in the Bronze Age, detectable from analyses including haplotype sharing with both ancient and modern genomes, D-statistics and Y-chromosome lineages. However, the limited nature of this introgression contrasts with the major Steppe migration turnovers within third Millennium northern Europe and echoes the survival of non-Indo-European language in Iberia. Changes in genomic estimates of individual height across Europe are also associated with these major cultural transitions, and ancestral components continue to correlate with modern differences in stature.

  6. A phantom based method for deriving typical patient doses from measurements of dose-area product on populations of patients

    International Nuclear Information System (INIS)

    Chapple, C.-L.; Broadhead, D.A.

    1995-01-01

    One of the chief sources of uncertainty in the comparison of patient dosimetry data is the influence of patient size on dose. Dose has been shown to relate closely to the equivalent diameter of the patient. This concept has been used to derive a prospective, phantom based method for determining size correction factors for measurements of dose-area product. The derivation of the size correction factor has been demonstrated mathematically, and the appropriate factor determined for a number of different X-ray sets. The use of phantom measurements enables the effect of patient size to be isolated from other factors influencing patient dose. The derived factors agree well with those determined retrospectively from patient dose survey data. Size correction factors have been applied to the results of a large scale patient dose survey, and this approach has been compared with the method of selecting patients according to their weight. For large samples of data, mean dose-area product values are independent of the analysis method used. The chief advantage of using size correction factors is that it allows all patient data to be included in a survey, whereas patient selection has been shown to exclude approximately half of all patients. (author)

  7. Maternal and fetal characteristics affect discrepancies between pregnancy-dating methods: a population-based cross-sectional register study.

    Science.gov (United States)

    Kullinger, Merit; Wesström, Jan; Kieler, Helle; Skalkidou, Alkistis

    2017-01-01

    Gestational age is estimated by ultrasound using fetal size as a proxy for age, although variance in early growth affects reliability. The aim of this study was to identify characteristics associated with discrepancies between last menstrual period-based (EDD-LMP) and ultrasound-based (EDD-US) estimated delivery dates. We identified all singleton births (n = 1 201 679) recorded in the Swedish Medical Birth Register in 1995-2010, to assess the association between maternal/fetal characteristics and large negative and large positive discrepancies (EDD-LMP earlier than EDD-US and 10th percentile in the discrepancy distribution vs. EDD-LMP later than EDD-US and 90th percentile). Analyses were adjusted for age, parity, height, body mass index, smoking, and employment status. Women with a body mass index >40 kg/m 2 had the highest odds for large negative discrepancies (-9 to -20 days) [odds ratio (OR) 2.16, 95% CI 2.01-2.33]. Other factors associated with large negative discrepancies were: diabetes, young maternal age, multiparity, body mass index between 30 and 39.9 kg/m 2 or +1 SD), and unemployment. Several maternal and fetal characteristics were associated with discrepancies between dating methods. Systematic associations of discrepancies with maternal height, fetal sex, and partly obesity, may reflect an influence on the precision of the ultrasound estimate due to variance in early growth. © 2016 The Authors. Acta Obstetricia et Gynecologica Scandinavica published by John Wiley & Sons Ltd on behalf of Nordic Federation of Societies of Obstetrics and Gynecology (NFOG).

  8. High coffee consumption and different brewing methods in relation to postmenopausal endometrial cancer risk in the Norwegian women and cancer study: a population-based prospective study.

    Science.gov (United States)

    Gavrilyuk, Oxana; Braaten, Tonje; Skeie, Guri; Weiderpass, Elisabete; Dumeaux, Vanessa; Lund, Eiliv

    2014-03-25

    Coffee and its compounds have been proposed to inhibit endometrial carcinogenesis. Studies in the Norwegian population can be especially interesting due to the high coffee consumption and increasing incidence of endometrial cancer in the country. A total of 97 926 postmenopausal Norwegian women from the population-based prospective Norwegian Women and Cancer (NOWAC) Study, were included in the present analysis. We evaluated the general association between total coffee consumption and endometrial cancer risk as well as the possible impact of brewing method. Multivariate Cox regression analysis was used to estimate risks, and heterogeneity tests were performed to compare brewing methods. During an average of 10.9 years of follow-up, 462 incident endometrial cancer cases were identified. After multivariate adjustment, significant risk reduction was found among participants who drank ≥8 cups/day of coffee with a hazard ratio of 0.52 (95% confidence interval, CI 0.34-0.79). However, we did not observe a significant dose-response relationship. No significant heterogeneity in risk was found when comparing filtered and boiled coffee brewing methods. A reduction in endometrial cancer risk was observed in subgroup analyses among participants who drank ≥8 cups/day and had a body mass index ≥25 kg/m2, and in current smokers. These data suggest that in this population with high coffee consumption, endometrial cancer risk decreases in women consuming ≥8 cups/day, independent of brewing method.

  9. A dynamic activity-based population modelling approach to evaluate exposure to air pollution: Methods and application to a Dutch urban area

    International Nuclear Information System (INIS)

    Beckx, Carolien; Int Panis, Luc; Arentze, Theo; Janssens, Davy; Torfs, Rudi; Broekx, Steven; Wets, Geert

    2009-01-01

    Recent air quality studies have highlighted that important differences in pollutant concentrations can occur over the day and between different locations. Traditional exposure analyses, however, assume that people are only exposed to pollution at their place of residence. Activity-based models, which recently have emerged from the field of transportation research, offer a technique to micro-simulate activity patterns of a population with a high resolution in space and time. Due to their characteristics, this model can be applied to establish a dynamic exposure assessment to air pollution. This paper presents a new exposure methodology, using a micro-simulator of activity-travel behaviour, to develop a dynamic exposure assessment. The methodology is applied to a Dutch urban area to demonstrate the advantages of the approach for exposure analysis. The results for the exposure to PM 10 and PM 2.5 , air pollutants considered as hazardous for human health, reveal large differences between the static and the dynamic approach, mainly due to an underestimation of the number of hours spent in the urban region by the static method. We can conclude that this dynamic population modelling approach is an important improvement over traditional methods and offers a new and more sensitive way for estimating population exposure to air pollution. In the light of the new European directive, aimed at reducing the exposure of the population to PM 2.5 , this new approach contributes to a much more accurate exposure assessment that helps evaluate policies to reduce public exposure to air pollution

  10. Data-driven drug safety signal detection methods in pharmacovigilance using electronic primary care records: A population based study

    Directory of Open Access Journals (Sweden)

    Shang-Ming Zhou

    2017-04-01

    Data-driven analytic methods are a valuable aid to signal detection of ADEs from large electronic health records for drug safety monitoring. This study finds the methods can detect known ADE and so could potentially be used to detect unknown ADE.

  11. Connecting the Invisible Dots: Network-Based Methods to Reach a Hidden Population at Risk for Suicide

    Science.gov (United States)

    Duberstein, Paul R; Tu, Xin; Tang, Wan; Lu, Naiji; Homan, Christopher M

    2009-01-01

    Young lesbian, gay, and bisexual (young LGB) individuals report higher rates of suicide ideation and attempts from their late teens through early twenties. Their high rate of Internet use suggests that online social networks offer a novel opportunity to reach them. This study explores online social networks as a venue for prevention research targeting young LGB. An automated data collection program was used to map the social connections between LGB self-identified individuals between 16 and 24 years old participating in an online social network. We then completed a descriptive analysis of the structural characteristics known to affect diffusion within such networks. Finally, we conducted Monte Carlo simulations of peer-driven diffusion of a hypothetical preventive intervention within the observed network under varying starting conditions. We mapped a network of 100,014 young LGB. The mean age was 20.4 years. The mean nodal degree was 137.5, representing an exponential degree distribution ranging from 1 through 4,309. Monte Carlo simulations revealed that a peer-driven preventive intervention ultimately reached final sample sizes of up to 18,409 individuals. The network’s structure is consistent with other social networks in terms of the underlying degree distribution. Such networks are typically formed dynamically through a process of preferential attachment. This implies that some individuals could be more important to target to facilitate the diffusion of interventions. However, in terms of determining the success of an intervention targeting this population, our simulation results suggest that varying the number of peers that can be recruited is more important than increasing the number of randomly-selected starting individuals. This has implications for intervention design. Given the potential to access this previously isolated population, this novel approach represents a promising new frontier in suicide prevention and other research areas. PMID:19540641

  12. Trends and regional variations in provision of contraception methods in a commercially insured population in the United States based on nationally proposed measures.

    Science.gov (United States)

    Law, A; Yu, J S; Wang, W; Lin, J; Lynen, R

    2017-09-01

    Three measures to assess the provision of effective contraception methods among reproductive-aged women have recently been endorsed for national public reporting. Based on these measures, this study examined real-world trends and regional variations of contraceptive provision in a commercially insured population in the United States. Women 15-44years old with continuous enrollment in each year from 2005 to 2014 were identified from a commercial claims database. In accordance with the proposed measures, percentages of women (a) provided most effective or moderately effective (MEME) methods of contraception and (b) provided a long-acting reversible contraceptive (LARC) method were calculated in two populations: women at risk for unintended pregnancy and women who had a live birth within 3 and 60days of delivery. During the 10-year period, the percentages of women at risk for unintended pregnancy provided MEME contraceptive methods increased among 15-20-year-olds (24.5%-35.9%) and 21-44-year-olds (26.2%-31.5%), and those provided a LARC method also increased among 15-20-year-olds (0.1%-2.4%) and 21-44-year-olds (0.8%-3.9%). Provision of LARC methods increased most in the North Central and West among both age groups of women. Provision of MEME contraceptives and LARC methods to women who had a live birth within 60days postpartum also increased across age groups and regions. This assessment indicates an overall trend of increasing provision of MEME contraceptive methods in the commercial sector, albeit with age group and regional variations. If implemented, these proposed measures may have impacts on health plan contraceptive access policy. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Efficiency of two-phase methods with focus on a planned population-based case-control study on air pollution and stroke

    Directory of Open Access Journals (Sweden)

    Strömberg Ulf

    2007-11-01

    Full Text Available Abstract Background We plan to conduct a case-control study to investigate whether exposure to nitrogen dioxide (NO2 increases the risk of stroke. In case-control studies, selective participation can lead to bias and loss of efficiency. A two-phase design can reduce bias and improve efficiency by combining information on the non-participating subjects with information from the participating subjects. In our planned study, we will have access to individual disease status and data on NO2 exposure on group (area level for a large population sample of Scania, southern Sweden. A smaller sub-sample will be selected to the second phase for individual-level assessment on exposure and covariables. In this paper, we simulate a case-control study based on our planned study. We develop a two-phase method for this study and compare the performance of our method with the performance of other two-phase methods. Methods A two-phase case-control study was simulated with a varying number of first- and second-phase subjects. Estimation methods: Method 1: Effect estimation with second-phase data only. Method 2: Effect estimation by adjusting the first-phase estimate with the difference between the adjusted and unadjusted second-phase estimate. The first-phase estimate is based on individual disease status and residential address for all study subjects that are linked to register data on NO2-exposure for each geographical area. Method 3: Effect estimation by using the expectation-maximization (EM algorithm without taking area-level register data on exposure into account. Method 4: Effect estimation by using the EM algorithm and incorporating group-level register data on NO2-exposure. Results The simulated scenarios were such that, unbiased or marginally biased ( Conclusion In the setting described here, method 4 had the best performance in order to improve efficiency, while adjusting for varying participation rates across areas.

  14. A Method to Estimate the Size and Characteristics of HIV-positive Populations Using an Individual-based Stochastic Simulation Model

    DEFF Research Database (Denmark)

    Nakagawa, Fumiyo; van Sighem, Ard; Thiebaut, Rodolphe

    2016-01-01

    % plausibility range: 39,900-45,560) men who have sex with men were estimated to be living with HIV in the UK, of whom 10,400 (6,160-17,350) were undiagnosed. There were an estimated 3,210 (1,730-5,350) infections per year on average between 2010 and 2013. Sixty-two percent of the total HIV-positive population......It is important not only to collect epidemiologic data on HIV but to also fully utilize such information to understand the epidemic over time and to help inform and monitor the impact of policies and interventions. We describe and apply a novel method to estimate the size and characteristics of HIV-positive...... populations. The method was applied to data on men who have sex with men living in the UK and to a pseudo dataset to assess performance for different data availability. The individual-based simulation model was calibrated using an approximate Bayesian computation-based approach. In 2013, 48,310 (90...

  15. Gastroesophageal Reflux Disease: A Population Based Study

    OpenAIRE

    Nwokediuko, Sylvester

    2009-01-01

    Background The prevalence of gastroesophageal reflux disease varies in different parts of the world. There are no population based studies in Nigeria. The main objectives of this study were to determine the prevalence and risk factors for gastroesophageal reflux disease in a population of Nigerian medical students. Methods The Carlsson-Dent questionnaire was administered to medical students in the clinical phase of their training at the University of Nigeria, Enugu Campus. Some putative risk ...

  16. Acceptable risk of contact allergy in the general population assessed by CE-DUR--a method to detect and categorize contact allergy epidemics based on patient data

    DEFF Research Database (Denmark)

    Thyssen, Jacob Pontoppidan; Menné, Torkil; Schnuch, Axel

    2009-01-01

    of persons eligible for patch testing each year based on patch test sales data. A reverse CE-DUR was performed to make delineations between the 10-year prevalence of contact allergy in the general population and the corresponding theoretical prevalences of contact allergy observed among patients...

  17. Access to Difficult-to-reach Population Subgroups: A Family Midwife Based Home Visiting Service for Implementing Nutrition-related Preventive Activities - A Mixed Methods Explorative Study

    Directory of Open Access Journals (Sweden)

    Helena Walz

    2015-08-01

    Full Text Available Health and social inequality are tightly linked and still pose an important public health problem. However, vulnerable and disadvantaged populations are difficult to reach for health-related interventions. Given the long-lasting effects of an adverse, particular nutrition-related, intrauterine and neonatal environment on health development (perinatal programming, an early and easy access is essential for sustainable interventions. The goal of this explorative study was therefore to elucidate whether an existing access of family midwives (FMs to families in need of support could be an option to implement effective public health and nutrition interventions. To that end three research objectives were formulated: (1 to determine whether a discernible impact of home visits by FMs can be described; (2 to identify subgroups among these families in need of more specific interventions; (3 to determine how relevant nutrition-related topics are for both FMs and the supported families. For addressing these objectives a mixed methods design was used: Routine documentation data from 295 families visited by a family midwife (FM were analyzed (secondary analysis, and structured expert interviews with FMs were conducted and analyzed. Study reporting followed the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology statement. Based on the FMs reports, a significant improvement (p < 0.001 regarding psycho-social variables could be determined after the home visits. Single mothers, however, seemed to benefit less from the FMs service compared to their counterparts (p = 0.015. Nutritional counseling was demanded by 89% of the families during the home visits. In addition, nutrition-related topics were reported in the interviews to be of high interest to both families and the FMs. Based on the obtained results it is concluded that FMs home visits offer a promising access to vulnerable and disadvantaged families for implementing nutrition

  18. A New Subspecies Identification and Population Study of the Asian Small-Clawed Otter (Aonyx cinereus in Malay Peninsula and Southern Thailand Based on Fecal DNA Method

    Directory of Open Access Journals (Sweden)

    M. K. A. Rosli

    2014-01-01

    Full Text Available Three species of otter can be found throughout Malay Peninsula: Aonyx cinereus, Lutra sumatrana, and Lutrogale perspicillata. In this study, we focused on the A. cinereus population that ranges from the southern and the east coast to the northern regions of Malay Peninsula up to southern Thailand to review the relationships between the populations based on the mitochondrial D-loop region. Forty-eight samples from six populations were recognized as Johor, Perak, Terengganu, Kelantan, Ranong, and Thale Noi. Among the 48 samples, 33 were identified as A. cinereus, seven as L. sumatrana, and eight as L. perspicillata. Phylogenetically, two subclades formed for A. cinereus. The first subclade grouped all Malay Peninsula samples except for samples from Kelantan, and the second subclade grouped Kelantan samples with Thai sample. Genetic distance analysis supported the close relationships between Thai and Kelantan samples compared to the samples from Terengganu and the other Malaysian states. A minimum-spanning network showed that Kelantan and Thailand formed a haplogroup distinct from the other populations. Our results show that Thai subspecies A. cinereus may have migrated to Kelantan from Thai mainland. We also suggest the classification of a new subspecies from Malay Peninsula, the small-clawed otter named A. cinereus kecilensis.

  19. A new subspecies identification and population study of the Asian small-clawed otter (Aonyx cinereus) in Malay Peninsula and southern Thailand based on fecal DNA method.

    Science.gov (United States)

    Rosli, M K A; Syed-Shabthar, S M F; Abdul-Patah, P; Abdul-Samad, Z; Abdul, S N; Burhanuddin, M N; Zulkifli, N A; Shukor, M N; Budsabong, K; Changtragoon, S; Sekiguchi, T; Sasaki, H; Md-Zain, B M

    2014-01-01

    Three species of otter can be found throughout Malay Peninsula: Aonyx cinereus, Lutra sumatrana, and Lutrogale perspicillata. In this study, we focused on the A. cinereus population that ranges from the southern and the east coast to the northern regions of Malay Peninsula up to southern Thailand to review the relationships between the populations based on the mitochondrial D-loop region. Forty-eight samples from six populations were recognized as Johor, Perak, Terengganu, Kelantan, Ranong, and Thale Noi. Among the 48 samples, 33 were identified as A. cinereus, seven as L. sumatrana, and eight as L. perspicillata. Phylogenetically, two subclades formed for A. cinereus. The first subclade grouped all Malay Peninsula samples except for samples from Kelantan, and the second subclade grouped Kelantan samples with Thai sample. Genetic distance analysis supported the close relationships between Thai and Kelantan samples compared to the samples from Terengganu and the other Malaysian states. A minimum-spanning network showed that Kelantan and Thailand formed a haplogroup distinct from the other populations. Our results show that Thai subspecies A. cinereus may have migrated to Kelantan from Thai mainland. We also suggest the classification of a new subspecies from Malay Peninsula, the small-clawed otter named A. cinereus kecilensis.

  20. Comparison of gene-based rare variant association mapping methods for quantitative traits in a bovine population with complex familial relationships.

    Science.gov (United States)

    Zhang, Qianqian; Guldbrandtsen, Bernt; Calus, Mario P L; Lund, Mogens Sandø; Sahana, Goutam

    2016-08-17

    There is growing interest in the role of rare variants in the variation of complex traits due to increasing evidence that rare variants are associated with quantitative traits. However, association methods that are commonly used for mapping common variants are not effective to map rare variants. Besides, livestock populations have large half-sib families and the occurrence of rare variants may be confounded with family structure, which makes it difficult to disentangle their effects from family mean effects. We compared the power of methods that are commonly applied in human genetics to map rare variants in cattle using whole-genome sequence data and simulated phenotypes. We also studied the power of mapping rare variants using linear mixed models (LMM), which are the method of choice to account for both family relationships and population structure in cattle. We observed that the power of the LMM approach was low for mapping a rare variant (defined as those that have frequencies lower than 0.01) with a moderate effect (5 to 8 % of phenotypic variance explained by multiple rare variants that vary from 5 to 21 in number) contributing to a QTL with a sample size of 1000. In contrast, across the scenarios studied, statistical methods that are specialized for mapping rare variants increased power regardless of whether multiple rare variants or a single rare variant underlie a QTL. Different methods for combining rare variants in the test single nucleotide polymorphism set resulted in similar power irrespective of the proportion of total genetic variance explained by the QTL. However, when the QTL variance is very small (only 0.1 % of the total genetic variance), these specialized methods for mapping rare variants and LMM generally had no power to map the variants within a gene with sample sizes of 1000 or 5000. We observed that the methods that combine multiple rare variants within a gene into a meta-variant generally had greater power to map rare variants compared

  1. Search for heavy metals in specified groups of Bangladesh population. Part of a coordinated programme on nuclear-based methods for analysis of pollutants in human hair

    International Nuclear Information System (INIS)

    Mozammel Husain, M.

    1979-12-01

    Hair analysis is increasingly used as a method for assaying and monitoring human exposure to potentially toxic trace elements. More than 100 scalp hair samples were collected from an adult population in Bangladesh; a normalised protocol of sample collection and sample washing recommended by IAEA was used. Samples were charred, homogenised into powder and analysed by the PIXE technique using a 3 MeV Van de Graaf accelerator X-ray spectroscopy. Twelve elements (K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr, and Pb) were surveyed. Medians, arithmetic and geometric means and their respective uncertainties are reported. A comparison of these data with those reported in literature is given

  2. Population-based screening versus case detection.

    Directory of Open Access Journals (Sweden)

    Thomas Ravi

    2002-01-01

    Full Text Available India has a large burden of blindness and population-based screening is a strategy commonly employed to detect disease and prevent morbidity. However, not all diseases are amenable to screening. This communication examines the issue of "population-based screening" versus "case detection" in the Indian scenario. Using the example of glaucoma, it demonstrates that given the poor infrastructure, for a "rare" disease, case detection is more effective than population-based screening.

  3. Use of the SSLP-based method for detection of rare apomictic events in a sexual AtSERK1 transgenic Arabidopsis population

    NARCIS (Netherlands)

    Kantama, L.; Lambert, J.M.; Hu, H.; Jong, de H.; Vries, de S.C.; Russinova, E.

    2006-01-01

    Here we present a screening method to evaluate the potential of genes to transfer aspects of apomixis into sexual crop plants. Based on the assumption that an apomictic progeny is an exact genetic replica of the mother plant we employed a set of single sequence length polymorphism (SSLP) markers to

  4. Population-based contracting (population health): part II.

    Science.gov (United States)

    Jacofsky, D J

    2017-11-01

    Modern healthcare contracting is shifting the responsibility for improving quality, enhancing community health and controlling the total cost of care for patient populations from payers to providers. Population-based contracting involves capitated risk taken across an entire population, such that any included services within the contract are paid for by the risk-bearing entity throughout the term of the agreement. Under such contracts, a risk-bearing entity, which may be a provider group, a hospital or another payer, administers the contract and assumes risk for contractually defined services. These contracts can be structured in various ways, from professional fee capitation to full global per member per month diagnosis-based risk. The entity contracting with the payer must have downstream network contracts to provide the care and facilities that it has agreed to provide. Population health is a very powerful model to reduce waste and costs. It requires a deep understanding of the nuances of such contracting and the appropriate infrastructure to manage both networks and risk. Cite this article: Bone Joint J 2017;99-B:1431-4. ©2017 The British Editorial Society of Bone & Joint Surgery.

  5. Representativeness in population-based studies

    DEFF Research Database (Denmark)

    Drivsholm, Thomas Bo; Eplov, Lene Falgaard; Davidsen, Michael

    2006-01-01

    Decreasing rates of participation in population-based studies increasingly challenge the interpretation of study results, in both analytic and descriptive epidemiology. Consequently, estimates of possible differences between participants and non-participants are increasingly important...... for the interpretation of study results and generalization to the background population....

  6. Emerging chronic non-communicable diseases in rural communities of Northern Ethiopia: evidence using population-based verbal autopsy method in Kilite Awlaelo surveillance site.

    Science.gov (United States)

    Weldearegawi, Berhe; Ashebir, Yemane; Gebeye, Ejigu; Gebregziabiher, Tesfay; Yohannes, Mekonnen; Mussa, Seid; Berhe, Haftu; Abebe, Zerihun

    2013-12-01

    In countries where most deaths are outside health institutions and medical certification of death is absent, verbal autopsy (VA) method is used to estimate population level causes of death. VA data were collected by trained lay interviewers for 409 deaths in the surveillance site. Two physicians independently assigned cause of death using the International Classification of Diseases manual. In general, infectious and parasitic diseases accounted for 35.9% of death, external causes 15.9%, diseases of the circulatory system 13.4% and perinatal causes 12.5% of total deaths. Mortalities attributed to maternal causes and malnutrition were low, 0.2 and 1.5%, respectively. Causes of death varied by age category. About 22.1, 12.6 and 8.4% of all deaths of under 5-year-old children were due to bacterial sepsis of the newborn, acute lower respiratory infections such as neonatal pneumonia and prematurity including respiratory distress, respectively. For 5-15-year-old children, accidental drowning and submersion, accounting for 34.4% of all deaths in this age category, and accidental fall, accounting for 18.8%, were leading causes of death. Among 15-49-year-old adults, HIV/AIDS (16.3%) and tuberculosis (12.8%) were commonest causes of death, whereas tuberculosis and cerebrovascular diseases were major killers of those aged 50 years and above. In the rural district, mortality due to chronic non-communicable diseases was very high. The observed magnitude of death from chronic non-communicable disease is unlikely to be unique to this district. Thus, formulation of chronic disease prevention and control strategies is recommended.

  7. Comparación de cinco métodos para estimar la prevalencia de diabetes mellitus en estudios de base poblacional Comparison of five methods for estimating the prevalence of diabetes mellitus in population-based studies

    Directory of Open Access Journals (Sweden)

    Nicanor R. S. Pinto

    1997-10-01

    detectar los casos de diabetes mellitus previamente diagnosticados y se recomienda su uso para evaluaciones o planeamiento de servicios de salud. La medición de glucemia en ayunas (M3 como método exclusivo no reportó ventajas sobre el cuestionario individual (M2. Entre los métodos combinados o múltiples, la glucemia en ayunas junto con el cuestionario individual (M4 fue eficiente en relación con M5, que incorpora la glucemia a las 2 horas después de la ingestión de una sobrecarga oral de glucosa.To aid in the search for more practical and reliable methods for use in population-based studies of diabetes mellitus, this article compares five ways of estimating prevalence rates. The analysis was performed on secondary data from a cross-sectional study of a cluster sample of the adult population in nine state capitals in Brazil. The original study was carried out from 1986 to 1988. The 21 846 participants were classified as diabetic or not diabetic by five different methods: household questionnaires administered to the entire sample population (M1; individual questionnaires administered to the selected population (M2; measurement of fasting glucose levels in capillary blood, with levels > or = 120 mg/dL as the cutoff (M3; individual questionnaire and fasting capillary blood glucose > or = 120 mg/dL (M4; and individual questionnaire plus fasting capillary blood glucose > or = 200 mg/dL and capillary glucose 2 hours after oral glucose loading > or = 200 mg/dL (M5. Agreement between the methods was determined by comparison of the rates obtained and use of the kappa coefficient. The age-adjusted prevalence rates of diabetes varied according to the method used. Values obtained with M1 were lower than those indicated by M2; M3 values were higher than M2 values, except in the age group 60-69 years; and with M5 the rates were higher than with M4, except among persons 30-39 years old. With regard to the age-adjusted rates found by the various methods, M1 detected 84% of the M2

  8. Nationwide and population-based prescription patterns in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh

    2016-01-01

    OBJECTIVES: The aim of the present study was to describe prescription patterns and changes in these patterns over the last decade for patients diagnosed with bipolar disorder in mental healthcare, using population-based and nationwide data, and to relate the findings to recommendations from...... international guidelines. METHODS: A population-based, nationwide study was carried out. It included register-based longitudinal data on all patients with a first-ever contact with mental healthcare with a diagnosis of mania/bipolar disorder from the entire Danish population, and all prescription data...

  9. Variations in suicide method and in suicide occurrence by season and day of the week in Russia and the Nenets Autonomous Okrug, Northwestern Russia: a retrospective population-based mortality study.

    Science.gov (United States)

    Sumarokov, Yury A; Brenn, Tormod; Kudryavtsev, Alexander V; Nilssen, Odd

    2015-09-23

    Suicide is an important world health issue, especially in territories inhabited by indigenous people. This investigated differences in suicide rates, suicide methods, and suicide occurrence by month and day of the week among the indigenous and non-indigenous populations of the Nenets Autonomous Okrug (NAO) and to compare the findings from the NAO with national Russian statistics. In this retrospective population-based mortality study we investigated all suicides that occurred in the NAO in 2002-2012 (N = 252). Suicide method and the month and day of the week suicide occurred was taken from autopsy reports and disaggregated by ethnic group (indigenous and non-indigenous) and sex. Data from the NAO were then compared with national data from the Russian Federal Statistics Service (Rosstat). Hanging was the most common suicide method in the NAO in both indigenous and non-indigenous populations. The proportion of suicides by hanging among males was lower in the NAO than in national data (69.3 vs 86.2 %), but the inverse was true for females (86.5 vs 74.9 %). Suicide by firearm and by cutting was significantly higher among the indigenous population in the NAO when compared with national data. Peaks in suicide occurrence were observed in May and September in the NAO, whereas national data showed only one peak in May. Suicide occurrence in the indigenous population of the NAO was highest in April, while the non-indigenous population showed peaks in May and September. Suicide occurrence in the NAO was highest on Fridays; in national data this occurrence was highest on Mondays. We showed different relative frequencies of suicide by hanging, cutting, and firearm, as well as different suicide occurrence by month and day of the week in the NAO compared with Russia as a whole. These results can be used to plan suicide prevention activities in the Russian Arctic.

  10. Design and methods of a population-based natural history study of cervical neoplasia in a rural province of Costa Rica: the Guanacaste Project

    Directory of Open Access Journals (Sweden)

    Herrero Rolando

    1997-01-01

    Full Text Available This paper reports on the enrollment phase of a population-based natural history study of cervical neoplasia in Guanacaste, a rural province of Costa Rica with consistently high rates of invasive cervical cancer. The main goals of the study are to investigate the role of human papillomavirus (HPV infection and its co-factors in the etiology of high-grade cervical neoplasia, and to evaluate new cervical cancer screening technologies. To begin, a random sample of censal segments was selected and enumeration of all resident women 18 years of age and over was conducted with the aid of outreach workers of the Costa Rican Ministry of Health. Of the 10 738 women who were eligible to participate, 10 049 (93.6% were interviewed after giving written informed consent. After the interview on cervical cancer risk factors was administered, a pelvic examination was performed on those women who reported previous sexual activity. The pelvic examination included a vaginal pH determination and collection of cervical cells for cytologic diagnosis using three different techniques. Additional cervical cells were collected for determination of the presence and amount of DNA from 16 different types of HPV, and two photographic images of the cervix were taken and interpreted offsite by an expert colposcopist. Finally, blood samples were collected for immunologic and micronutrient assays. Women with any abnormal cytologic diagnosis or a positive Cervigram, as well as a sample of the whole group, were referred for colposcopy, and biopsies were taken when lesions were observed. The enrollment screening will serve as the basis for a prevalent case-control study, and the members of the cohort free from serious disease will be followed actively, at intervals of no more than a year, to study the natural history of HPV infection and the origins of high-grade squamous intraepithelial lesions (HSIL. Details of the field operation are outlined, with particular reference to the

  11. Geometry-based populated chessboard recognition

    Science.gov (United States)

    Xie, Youye; Tang, Gongguo; Hoff, William

    2018-04-01

    Chessboards are commonly used to calibrate cameras, and many robust methods have been developed to recognize the unoccupied boards. However, when the chessboard is populated with chess pieces, such as during an actual game, the problem of recognizing the board is much harder. Challenges include occlusion caused by the chess pieces, the presence of outlier lines and low viewing angles of the chessboard. In this paper, we present a novel approach to address the above challenges and recognize the chessboard. The Canny edge detector and Hough transform are used to capture all possible lines in the scene. The k-means clustering and a k-nearest-neighbors inspired algorithm are applied to cluster and reject the outlier lines based on their Euclidean distances to the nearest neighbors in a scaled Hough transform space. Finally, based on prior knowledge of the chessboard structure, a geometric constraint is used to find the correspondences between image lines and the lines on the chessboard through the homography transformation. The proposed algorithm works for a wide range of the operating angles and achieves high accuracy in experiments.

  12. Statistical methods for detecting and comparing periodic data and their application to the nycthemeral rhythm of bodily harm: A population based study

    LENUS (Irish Health Repository)

    Stroebel, Armin M

    2010-11-08

    Abstract Background Animals, including humans, exhibit a variety of biological rhythms. This article describes a method for the detection and simultaneous comparison of multiple nycthemeral rhythms. Methods A statistical method for detecting periodic patterns in time-related data via harmonic regression is described. The method is particularly capable of detecting nycthemeral rhythms in medical data. Additionally a method for simultaneously comparing two or more periodic patterns is described, which derives from the analysis of variance (ANOVA). This method statistically confirms or rejects equality of periodic patterns. Mathematical descriptions of the detecting method and the comparing method are displayed. Results Nycthemeral rhythms of incidents of bodily harm in Middle Franconia are analyzed in order to demonstrate both methods. Every day of the week showed a significant nycthemeral rhythm of bodily harm. These seven patterns of the week were compared to each other revealing only two different nycthemeral rhythms, one for Friday and Saturday and one for the other weekdays.

  13. The potential impact of a social redistribution of specific risk factors on socioeconomic inequalities in mortality: Illustration of a method based on population attributable fractions

    NARCIS (Netherlands)

    R. Hoffmann (Rasmus); T.A. Eikemo (Terje); I. Kulhánová (Ivana); E. Dahl; P. Deboosere (Patrick); D. Dźurov́ (Dagmar); H. van Oyen (Herman); J. Rychtanŕikov́ (Jitka); B.H. Strand; J.P. Mackenbach (Johan)

    2013-01-01

    textabstractBackground: Socioeconomic differences in health are a major challenge for public health. However, realistic estimates to what extent they are modifiable are scarce. This problem can be met through the systematic application of the population attributable fraction (PAF) to socioeconomic

  14. Attribute-Based Methods

    Science.gov (United States)

    Thomas P. Holmes; Wiktor L. Adamowicz

    2003-01-01

    Stated preference methods of environmental valuation have been used by economists for decades where behavioral data have limitations. The contingent valuation method (Chapter 5) is the oldest stated preference approach, and hundreds of contingent valuation studies have been conducted. More recently, and especially over the last decade, a class of stated preference...

  15. Detailed methods of two home-based vegetable gardening intervention trials to improve diet, physical activity, and quality of life in two different populations of cancer survivors.

    Science.gov (United States)

    Cases, Mallory G; Frugé, Andrew D; De Los Santos, Jennifer F; Locher, Julie L; Cantor, Alan B; Smith, Kerry P; Glover, Tony A; Cohen, Harvey J; Daniel, Michael; Morrow, Casey D; Moellering, Douglas R; Demark-Wahnefried, Wendy

    2016-09-01

    Cancer survivors suffer from long-term adverse effects that reduce health-related quality of life (QOL) and physical functioning, creating an urgent need to develop effective, durable, and disseminable interventions. Harvest for Health, a home-based vegetable gardening intervention, holds promise for these domains. This report describes the methods and recruitment experiences from two randomized controlled feasibility trials that employ a waitlist-controlled design. Delivered in partnership with Cooperative Extension Master Gardeners, this intervention provides one-on-one mentorship of cancer survivors in planning and maintaining three seasonal vegetable gardens over 12months. The primary aim is to determine intervention feasibility and acceptability; secondary aims are to explore effects on objective and subjective measures of diet, physical activity and function, and QOL and examine participant factors associated with potential effects. One trial is conducted exclusively among 82 female breast cancer survivors residing in the Birmingham, AL metropolitan area (BBCS); another broadly throughout Alabama among 46 older cancer survivors aged >60 (ASCS). Response rates were 32.6% (BBCS) and 52.3% (ASCS). Both trials exceeded 80% of their accrual target. Leading reasons for ineligibility were removal of >10 lymph nodes (lymphedema risk factor), lack of physician approval, and unwillingness to be randomized to the waitlist. To date, recruitment and implementation of Harvest for Health appears feasible. Although both studies encountered recruitment challenges, lessons learned can inform future larger-scale studies. Vegetable gardening interventions are of interest to cancer survivors and may provide opportunities to gain life skills leading to improvements in overall health and QOL. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. New methods for sampling sparse populations

    Science.gov (United States)

    Anna Ringvall

    2007-01-01

    To improve surveys of sparse objects, methods that use auxiliary information have been suggested. Guided transect sampling uses prior information, e.g., from aerial photographs, for the layout of survey strips. Instead of being laid out straight, the strips will wind between potentially more interesting areas. 3P sampling (probability proportional to prediction) uses...

  17. The potential impact of a social redistribution of specific risk factors on socioeconomic inequalities in mortality: illustration of a method based on population attributable fractions.

    Science.gov (United States)

    Hoffmann, Rasmus; Eikemo, Terje Andreas; Kulhánová, Ivana; Dahl, Espen; Deboosere, Patrick; Dzúrová, Dagmar; van Oyen, Herman; Rychtaríková, Jitka; Strand, Bjørn Heine; Mackenbach, Johan P

    2013-01-01

    Socioeconomic differences in health are a major challenge for public health. However, realistic estimates to what extent they are modifiable are scarce. This problem can be met through the systematic application of the population attributable fraction (PAF) to socioeconomic health inequalities. The authors used cause-specific mortality data by educational level from Belgium, Norway and Czech Republic and data on the prevalence of smoking, alcohol, lack of physical activity and high body mass index from national health surveys. Information on the impact of these risk factors on mortality comes from the epidemiological literature. The authors calculated PAFs to quantify the impact on socioeconomic health inequalities of a social redistribution of risk factors. The authors developed an Excel tool covering a wide range of possible scenarios and the authors compare the results of the PAF approach with a conventional regression. In a scenario where the whole population gets the risk factor prevalence currently seen among the highly educated inequalities in mortality can be reduced substantially. According to the illustrative results, the reduction of inequality for all risk factors combined varies between 26% among Czech men and 94% among Norwegian men. Smoking has the highest impact for both genders, and physical activity has more impact among women. After discussing the underlying assumptions of the PAF, the authors concluded that the approach is promising for estimating the extent to which health inequalities can be potentially reduced by interventions on specific risk factors. This reduction is likely to differ substantially between countries, risk factors and genders.

  18. Population based reference intervals for common blood ...

    African Journals Online (AJOL)

    Population based reference intervals for common blood haematological and biochemical parameters in the Akuapem north district. K.A Koram, M.M Addae, J.C Ocran, S Adu-amankwah, W.O Rogers, F.K Nkrumah ...

  19. Comparison of gene-based rare variant association mapping methods for quantitative traits in a bovine population with complex familial relationships

    NARCIS (Netherlands)

    Zhang, Qianqian; Guldbrandtsen, Bernt; Calus, Mario P.L.; Lund, Mogens Sandø; Sahana, Goutam

    2016-01-01

    Background: There is growing interest in the role of rare variants in the variation of complex traits due to increasing evidence that rare variants are associated with quantitative traits. However, association methods that are commonly used for mapping common variants are not effective to map

  20. Costs of detection bias in index-based population monitoring

    Science.gov (United States)

    Moore, C.T.; Kendall, W.L.

    2004-01-01

    Managers of wildlife populations commonly rely on indirect, count-based measures of the population in making decisions regarding conservation, harvest, or control. The main appeal in the use of such counts is their low material expense compared to methods that directly measure the population. However, their correct use rests on the rarely-tested but often-assumed premise that they proportionately reflect population size, i.e., that they constitute a population index. This study investigates forest management for the endangered Red-cockaded Woodpecker (Picoides borealis) and the Wood Thrush (Hylocichla mustelina) at the Piedmont National Wildlife Refuge in central Georgia, U.S.A. Optimal decision policies for a joint species objective were derived for two alternative models of Wood Thrush population dynamics. Policies were simulated under scenarios of unbiasedness, consistent negative bias, and habitat-dependent negative bias in observed Wood Thrush densities. Differences in simulation outcomes between biased and unbiased detection scenarios indicated the expected loss in resource objectives (here, forest habitat and birds) through decision-making based on biased population counts. Given the models and objective function used in our analysis, expected losses were as great as 11%, a degree of loss perhaps not trivial for applications such as endangered species management. Our analysis demonstrates that costs of uncertainty about the relationship between the population and its observation can be measured in units of the resource, costs which may offset apparent savings achieved by collecting uncorrected population counts.

  1. Economic costs of minor depression: a population-based study.

    NARCIS (Netherlands)

    Cuijpers, P.; Smit, H.F.E.; Oostenbrink, J.; de Graaf, R.; ten Have, M.; Beekman, A.T.F.

    2007-01-01

    Objective: Although the clinical relevance of minor depression has been demonstrated in many studies, the economic costs are not well explored. In this study, we examine the economic costs of minor depression. Method: In a large-scale, population-based study in the Netherlands (n = 5504) the costs

  2. Economic costs of minor depression: a population-based study

    NARCIS (Netherlands)

    Cuijpers, P.; Smit, H.F.E.; Oostenbrink, J.; Graaf, de R.; Have, M. ten; Beekman, A.T.F.

    2006-01-01

    Objective: Although the clinical relevance of minor depression has been demonstrated in many studies, the economic costs are not well explored. In this study, we examine the economic costs of minor depression. Method: In a large-scale, population-based study in the Netherlands (n ¼ 5504) the costs

  3. Economic costs of minor depression: a population-based study

    NARCIS (Netherlands)

    Cuijpers, P.; Smit, H.F.E.; Oostenbrink, J.; de Graaf, R.; ten Have, M.; Beekman, A.T.F.

    2006-01-01

    Objective: Although the clinical relevance of minor depression has been demonstrated in many studies, the economic costs are not well explored. In this study, we examine the economic costs of minor depression. Method: In a large-scale, population-based study in the Netherlands (n = 5504) the costs

  4. Economic costs of social phobia: a population-based study.

    NARCIS (Netherlands)

    Acarturk, C.; Smit, H.F.E.; de Graaf, R.; van Straten, A.; ten Have, M.; Cuijpers, P.

    2009-01-01

    Background: Information about the economic costs of social phobia is scant. In this study, we examine the economic costs of social phobia and subthreshold social phobia. Methods: Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) which is a population-based

  5. Internet-based data inclusion in a population-based European collaborative follow-up study of inflammatory bowel disease patients: description of methods used and analysis of factors influencing response rates.

    Science.gov (United States)

    Wolters, Frank L; van Zeijl, Gilbert; Sijbrandij, Jildou; Wessels, Frederik; O'Morain, Colm; Limonard, Charles; Russel, Maurice G; Stockbrugger, Reinhold W

    2005-12-07

    To describe an Internet-based data acquisition facility for a European 10-year clinical follow-up study project of a population-based cohort of inflammatory bowel disease (IBD) patients and to investigate the influence of demographic and disease related patient characteristics on response rates. Thirteen years ago, the European Collaborative study group of IBD (EC-IBD) initiated a population-based prospective inception cohort of 2 201 uniformly diagnosed IBD patients within 20 well-described geographical areas in 11 European countries and Israel. For the 10-year follow-up of this cohort, an electronic patient questionnaire (ePQ) and electronic physician per patient follow-up form (ePpPFU) were designed as two separate data collecting instruments and made available through an Internet-based website. Independent demographic and clinical determinants of ePQ participation were analyzed using multivariate logistic regression. In 958 (316 CD and 642 UC) out of a total number of 1 505 (64%) available IBD patients, originating from 13 participating centers from nine different countries, both ePQ and ePpPFU were completed. Patients older than 40 years at ePQ completion (OR: 1.53 (95%CI: 1.14-2.05)) and those with active disease during the 3 mo previous to ePQ completion (OR: 3.32 (95%CI: 1.57-7.03)) were significantly more likely to respond. An Internet-based data acquisition tool appeared successful in sustaining a unique Western-European and Israelian multi-center 10-year clinical follow-up study project in patients afflicted with IBD.

  6. Population Estimation with Mark and Recapture Method Program

    International Nuclear Information System (INIS)

    Limohpasmanee, W.; Kaewchoung, W.

    1998-01-01

    Population estimation is the important information which required for the insect control planning especially the controlling with SIT. Moreover, It can be used to evaluate the efficiency of controlling method. Due to the complexity of calculation, the population estimation with mark and recapture methods were not used widely. So that, this program is developed with Qbasic on the purpose to make it accuracy and easier. The program evaluation consists with 6 methods; follow Seber's, Jolly-seber's, Jackson's Ito's, Hamada's and Yamamura's methods. The results are compared with the original methods, found that they are accuracy and more easier to applied

  7. Febrile seizures: a population-based study

    Directory of Open Access Journals (Sweden)

    Juliane S. Dalbem

    2015-11-01

    Full Text Available Objectives: To determine the prevalence of benign febrile seizures of childhood and describe the clinical and epidemiological profile of this population. Methods: This was a population-based, cross-sectional study, carried out in the city of Barra do Bugres, MT, Brazil, from August 2012 to August 2013. Data were collected in two phases. In the first phase, a questionnaire that was previously validated in another Brazilian study was used to identify suspected cases of seizures. In the second phase, a neurological evaluation was performed to confirm diagnosis. Results: The prevalence was 6.4/1000 inhabitants (95% CI: 3.8–10.1. There was no difference between genders. Simple febrile seizures were found in 88.8% of cases. A family history of febrile seizures in first-degree relatives and history of epilepsy was present in 33.3% and 11.1% of patients, respectively. Conclusions: The prevalence of febrile seizures in Midwestern Brazil was lower than that found in other Brazilian regions, probably due to the inclusion only of febrile seizures with motor manifestations and differences in socioeconomic factors among the evaluated areas. Resumo: Objetivos: Estabelecer a prevalência das crises febris e descrever o perfil clínico e epidemiológico dessa população. Métodos: Estudo transversal de base populacional realizado na cidade de Barra do Bugres (MT, no período de agosto de 2012 a agosto de 2013. Os dados foram coletados em duas etapas. Na primeira fase utilizamos um questionário validado previamente em outro estudo brasileiro, para identificação de casos suspeitos de crises epilépticas. Na segunda etapa realizamos a avaliação neuroclínica para confirmação diagnóstica. Resultados: A prevalência de crise febril foi de 6,4/1000 habitantes (IC95% 3,8; 10,1. Não houve diferença entre os sexos. As crises febris simples foram encontradas em 88,8% dos casos. A história familiar de crise febril e epilepsia em parentes de 1° grau esteve

  8. Methods in Logic Based Control

    DEFF Research Database (Denmark)

    Christensen, Georg Kronborg

    1999-01-01

    Desing and theory of Logic Based Control systems.Boolean Algebra, Karnaugh Map, Quine McClusky's algorithm. Sequential control design. Logic Based Control Method, Cascade Control Method. Implementation techniques: relay, pneumatic, TTL/CMOS,PAL and PLC- and Soft_PLC implementation. PLC...

  9. Measuring populism: comparing two methods of content analysis

    NARCIS (Netherlands)

    Rooduijn, M.; Pauwels, T.

    2011-01-01

    The measurement of populism - particularly over time and space - has received only scarce attention. In this research note two different ways to measure populism are compared: a classical content analysis and a computer-based content analysis. An analysis of political parties in the United Kingdom,

  10. Activity based costing (ABC Method

    Directory of Open Access Journals (Sweden)

    Prof. Ph.D. Saveta Tudorache

    2008-05-01

    Full Text Available In the present paper the need and advantages are presented of using the Activity BasedCosting method, need arising from the need of solving the information pertinence issue. This issue has occurreddue to the limitation of classic methods in this field, limitation also reflected by the disadvantages ofsuch classic methods in establishing complete costs.

  11. Reliability of different mark-recapture methods for population size estimation tested against reference population sizes constructed from field data.

    Directory of Open Access Journals (Sweden)

    Annegret Grimm

    Full Text Available Reliable estimates of population size are fundamental in many ecological studies and biodiversity conservation. Selecting appropriate methods to estimate abundance is often very difficult, especially if data are scarce. Most studies concerning the reliability of different estimators used simulation data based on assumptions about capture variability that do not necessarily reflect conditions in natural populations. Here, we used data from an intensively studied closed population of the arboreal gecko Gehyra variegata to construct reference population sizes for assessing twelve different population size estimators in terms of bias, precision, accuracy, and their 95%-confidence intervals. Two of the reference populations reflect natural biological entities, whereas the other reference populations reflect artificial subsets of the population. Since individual heterogeneity was assumed, we tested modifications of the Lincoln-Petersen estimator, a set of models in programs MARK and CARE-2, and a truncated geometric distribution. Ranking of methods was similar across criteria. Models accounting for individual heterogeneity performed best in all assessment criteria. For populations from heterogeneous habitats without obvious covariates explaining individual heterogeneity, we recommend using the moment estimator or the interpolated jackknife estimator (both implemented in CAPTURE/MARK. If data for capture frequencies are substantial, we recommend the sample coverage or the estimating equation (both models implemented in CARE-2. Depending on the distribution of catchabilities, our proposed multiple Lincoln-Petersen and a truncated geometric distribution obtained comparably good results. The former usually resulted in a minimum population size and the latter can be recommended when there is a long tail of low capture probabilities. Models with covariates and mixture models performed poorly. Our approach identified suitable methods and extended options to

  12. Are rapid population estimates accurate? A field trial of two different assessment methods.

    Science.gov (United States)

    Grais, Rebecca F; Coulombier, Denis; Ampuero, Julia; Lucas, Marcelino E S; Barretto, Avertino T; Jacquier, Guy; Diaz, Francisco; Balandine, Serge; Mahoudeau, Claude; Brown, Vincent

    2006-09-01

    Emergencies resulting in large-scale displacement often lead to populations resettling in areas where basic health services and sanitation are unavailable. To plan relief-related activities quickly, rapid population size estimates are needed. The currently recommended Quadrat method estimates total population by extrapolating the average population size living in square blocks of known area to the total site surface. An alternative approach, the T-Square, provides a population estimate based on analysis of the spatial distribution of housing units taken throughout a site. We field tested both methods and validated the results against a census in Esturro Bairro, Beira, Mozambique. Compared to the census (population: 9,479), the T-Square yielded a better population estimate (9,523) than the Quadrat method (7,681; 95% confidence interval: 6,160-9,201), but was more difficult for field survey teams to implement. Although applicable only to similar sites, several general conclusions can be drawn for emergency planning.

  13. Male Contraception: Research, New Methods, and Implications for Marginalized Populations.

    Science.gov (United States)

    Plana, Olivia

    2017-07-01

    The majority of research on contraception has focused on manipulating the female reproductive system. Recent studies have identified novel contraceptives for males, including hormonal- and nonhormonal-based therapeutics. Although these new contraceptives are still undergoing clinical trials, their development and potential future use in society necessitate serious consideration of their implications for reproductive health. Through my analysis of the research conducted on male contraception over time and the current therapeutics available, it is clear that male contraception has the potential to shift societal gender dynamics and provide males with greater control over their own reproduction. This article also identifies the implications of these novel contraceptives for marginalized populations, especially men of color and men of lower socioeconomic positions. To overcome barriers to contraception among these populations, public policy efforts are needed in order to motivate the development of programs that facilitate coverage of these new male contraceptives by health plans and to increase their availability to underserved communities. Health care providers will be responsible for educating patients about these novel male contraception options and the need to continue using existing methods (e.g., condoms) in order to prevent sexually transmitted infections. This article analyzes the research conducted on male contraception and identifies the implications of these novel therapeutics for marginalized groups of men in the United States to identify the interventions that will be necessary to help ensure that all men have access to these promising scientific innovations.

  14. Individual based population inference using tagging data

    DEFF Research Database (Denmark)

    Pedersen, Martin Wæver; Thygesen, Uffe Høgsbro; Baktoft, Henrik

    A hierarchical framework for simultaneous analysis of multiple related individual datasets is presented. The approach is very similar to mixed effects modelling as known from statistical theory. The model used at the individual level is, in principle, irrelevant as long as a maximum likelihood...... estimate and its uncertainty (Hessian) can be computed. The individual model used in this text is a hidden Markov model. A simulation study concerning a two-dimensional biased random walk is examined to verify the consistency of the hierarchical estimation framework. In addition, a study based on acoustic...... telemetry data from pike illustrates how the framework can identify individuals that deviate from the remaining population....

  15. Development and evaluation of a new method for sampling and monitoring the symphylid population in pineapple

    OpenAIRE

    Soler, A.; Gaude, J. M.; Marie-Alphonsine, P. A.; Vinatier, F.; Dole, B.; Govindin, J. C.; Fournier, P.; Quénéhervé, Patrick

    2011-01-01

    BACKGROUND: Symphylids (Hanseniella sp.) are polyphagous soilborne parasites. Today, symphylid populations on pineapple are monitored by observing root symptoms and the presence of symphylids at the bottom of basal leaves. The authors developed a reliable method with a bait and trap device to monitor symphylid populations in pineapple or fallow crops. The spatial distribution of the symphylid populations was evaluated using the variance/mean ratios and spatial analyses based on Moran's and Ge...

  16. Mapping population-based structural connectomes.

    Science.gov (United States)

    Zhang, Zhengwu; Descoteaux, Maxime; Zhang, Jingwen; Girard, Gabriel; Chamberland, Maxime; Dunson, David; Srivastava, Anuj; Zhu, Hongtu

    2018-05-15

    Advances in understanding the structural connectomes of human brain require improved approaches for the construction, comparison and integration of high-dimensional whole-brain tractography data from a large number of individuals. This article develops a population-based structural connectome (PSC) mapping framework to address these challenges. PSC simultaneously characterizes a large number of white matter bundles within and across different subjects by registering different subjects' brains based on coarse cortical parcellations, compressing the bundles of each connection, and extracting novel connection weights. A robust tractography algorithm and streamline post-processing techniques, including dilation of gray matter regions, streamline cutting, and outlier streamline removal are applied to improve the robustness of the extracted structural connectomes. The developed PSC framework can be used to reproducibly extract binary networks, weighted networks and streamline-based brain connectomes. We apply the PSC to Human Connectome Project data to illustrate its application in characterizing normal variations and heritability of structural connectomes in healthy subjects. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. DYNAMICS OF Cercospora zeina POPULATIONS IN MAIZE-BASED ...

    African Journals Online (AJOL)

    ACSS

    DYNAMICS OFCercospora zeina POPULATIONS IN MAIZE-BASED AGRO- ..... Population differentiation of Cercospora zeina in three districts of Uganda based on analysis of molecular variance ..... interactions: The example of the Erysiphe.

  18. Ambit determination method in estimating rice plant population density

    Directory of Open Access Journals (Sweden)

    Abu Bakar, B.,

    2017-11-01

    Full Text Available Rice plant population density is a key indicator in determining the crop setting and fertilizer application rate. It is therefore essential that the population density is monitored to ensure that a correct crop management decision is taken. The conventional method of determining plant population is by manually counting the total number of rice plant tillers in a 25 cm x 25 cm square frame. Sampling is done by randomly choosing several different locations within a plot to perform tiller counting. This sampling method is time consuming, labour intensive and costly. An alternative fast estimating method was developed to overcome this issue. The method relies on measuring the outer circumference or ambit of the contained rice plants in a 25 cm x 25 cm square frame to determine the number of tillers within that square frame. Data samples of rice variety MR219 were collected from rice plots in the Muda granary area, Sungai Limau Dalam, Kedah. The data were taken at 50 days and 70 days after seeding (DAS. A total of 100 data samples were collected for each sampling day. A good correlation was obtained for the variety of 50 DAS and 70 DAS. The model was then verified by taking 100 samples with the latching strap for 50 DAS and 70 DAS. As a result, this technique can be used as a fast, economical and practical alternative to manual tiller counting. The technique can potentially be used in the development of an electronic sensing system to estimate paddy plant population density.

  19. Methods for calculating population dose from atmospheric dispersion of radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, B L; Jow, H N; Lee, I S [Pittsburgh Univ., PA (USA)

    1978-06-01

    Curves are computed from which population dose (man-rem) due to dispersal of radioactivity from a point source can be calculated in the gaussian plume model by simple multiplication, and methods of using them and their limitations are considered. Illustrative examples are presented.

  20. Bacterial population in traditional sourdough evaluated by molecular methods

    NARCIS (Netherlands)

    Randazzo, C.L.; Heilig, G.H.J.; Restuccia, C.; Giudici, P.; Caggia, C.

    2005-01-01

    Aims: To study the microbial communities in artisanal sourdoughs, manufactured by traditional procedure in different areas of Sicily, and to evaluate the lactic acid bacteria (LAB) population by classical and culture-independent approaches. Methods and Results: Forty-five LAB isolates were

  1. Stochastic weighted particle methods for population balance equations

    International Nuclear Information System (INIS)

    Patterson, Robert I.A.; Wagner, Wolfgang; Kraft, Markus

    2011-01-01

    Highlights: → Weight transfer functions for Monte Carlo simulation of coagulation. → Efficient support for single-particle growth processes. → Comparisons to analytic solutions and soot formation problems. → Better numerical accuracy for less common particles. - Abstract: A class of coagulation weight transfer functions is constructed, each member of which leads to a stochastic particle algorithm for the numerical treatment of population balance equations. These algorithms are based on systems of weighted computational particles and the weight transfer functions are constructed such that the number of computational particles does not change during coagulation events. The algorithms also facilitate the simulation of physical processes that change single particles, such as growth, or other surface reactions. Four members of the algorithm family have been numerically validated by comparison to analytic solutions to simple problems. Numerical experiments have been performed for complex laminar premixed flame systems in which members of the class of stochastic weighted particle methods were compared to each other and to a direct simulation algorithm. Two of the weighted algorithms have been shown to offer performance advantages over the direct simulation algorithm in situations where interest is focused on the larger particles in a system. The extent of this advantage depends on the particular system and on the quantities of interest.

  2. QTL mapping for combining ability in different population-based ...

    Indian Academy of Sciences (India)

    2013-12-13

    Dec 13, 2013 ... ability and for geneticists to research the genetic basis of combining ability. [Li L., Sun C., ... population-based NCII designs by a simulation study. J. Genet. ... combining ability could also be applied to other population- based NCII ... was to estimate how different base populations, sample sizes, heritability ...

  3. Entropy-based benchmarking methods

    NARCIS (Netherlands)

    Temurshoev, Umed

    2012-01-01

    We argue that benchmarking sign-volatile series should be based on the principle of movement and sign preservation, which states that a bench-marked series should reproduce the movement and signs in the original series. We show that the widely used variants of Denton (1971) method and the growth

  4. Comparison of association mapping methods in a complex pedigreed population

    DEFF Research Database (Denmark)

    Sahana, Goutam; Guldbrandtsen, Bernt; Janss, Luc

    2010-01-01

    to collect SNP signals in intervals, to avoid the scattering of a QTL signal over multiple neighboring SNPs. Methods not accounting for genetic background (full pedigree information) performed worse, and methods using haplotypes were considerably worse with a high false-positive rate, probably due...... to the presence of low-frequency haplotypes. It was necessary to account for full relationships among individuals to avoid excess false discovery. Although the methods were tested on a cattle pedigree, the results are applicable to any population with a complex pedigree structure...

  5. Georeferenced Population Datasets of Mexico (GEO-MEX): Raster Based GIS Coverage of Mexican Population

    Data.gov (United States)

    National Aeronautics and Space Administration — The Raster Based GIS Coverage of Mexican Population is a gridded coverage (1 x 1 km) of Mexican population. The data were converted from vector into raster. The...

  6. Population control methods in stochastic extinction and outbreak scenarios.

    Directory of Open Access Journals (Sweden)

    Juan Segura

    Full Text Available Adaptive limiter control (ALC and adaptive threshold harvesting (ATH are two related control methods that have been shown to stabilize fluctuating populations. Large variations in population abundance can threaten the constancy and the persistence stability of ecological populations, which may impede the success and efficiency of managing natural resources. Here, we consider population models that include biological mechanisms characteristic for causing extinctions on the one hand and pest outbreaks on the other hand. These models include Allee effects and the impact of natural enemies (as is typical of forest defoliating insects. We study the impacts of noise and different levels of biological parameters in three extinction and two outbreak scenarios. Our results show that ALC and ATH have an effect on extinction and outbreak risks only for sufficiently large control intensities. Moreover, there is a clear disparity between the two control methods: in the extinction scenarios, ALC can be effective and ATH can be counterproductive, whereas in the outbreak scenarios the situation is reversed, with ATH being effective and ALC being potentially counterproductive.

  7. Population control methods in stochastic extinction and outbreak scenarios.

    Science.gov (United States)

    Segura, Juan; Hilker, Frank M; Franco, Daniel

    2017-01-01

    Adaptive limiter control (ALC) and adaptive threshold harvesting (ATH) are two related control methods that have been shown to stabilize fluctuating populations. Large variations in population abundance can threaten the constancy and the persistence stability of ecological populations, which may impede the success and efficiency of managing natural resources. Here, we consider population models that include biological mechanisms characteristic for causing extinctions on the one hand and pest outbreaks on the other hand. These models include Allee effects and the impact of natural enemies (as is typical of forest defoliating insects). We study the impacts of noise and different levels of biological parameters in three extinction and two outbreak scenarios. Our results show that ALC and ATH have an effect on extinction and outbreak risks only for sufficiently large control intensities. Moreover, there is a clear disparity between the two control methods: in the extinction scenarios, ALC can be effective and ATH can be counterproductive, whereas in the outbreak scenarios the situation is reversed, with ATH being effective and ALC being potentially counterproductive.

  8. A General Method for QTL Mapping in Multiple Related Populations Derived from Multiple Parents

    Directory of Open Access Journals (Sweden)

    Yan AO

    2009-03-01

    Full Text Available It's well known that incorporating some existing populations derived from multiple parents may improve QTL mapping and QTL-based breeding programs. However, no general maximum likelihood method has been available for this strategy. Based on the QTL mapping in multiple related populations derived from two parents, a maximum likelihood estimation method was proposed, which can incorporate several populations derived from three or more parents and also can be used to handle different mating designs. Taking a circle design as an example, we conducted simulation studies to study the effect of QTL heritability and sample size upon the proposed method. The results showed that under the same heritability, enhanced power of QTL detection and more precise and accurate estimation of parameters could be obtained when three F2 populations were jointly analyzed, compared with the joint analysis of any two F2 populations. Higher heritability, especially with larger sample sizes, would increase the ability of QTL detection and improve the estimation of parameters. Potential advantages of the method are as follows: firstly, the existing results of QTL mapping in single population can be compared and integrated with each other with the proposed method, therefore the ability of QTL detection and precision of QTL mapping can be improved. Secondly, owing to multiple alleles in multiple parents, the method can exploit gene resource more adequately, which will lay an important genetic groundwork for plant improvement.

  9. Estimation of the size of the female sex worker population in Rwanda using three different methods.

    Science.gov (United States)

    Mutagoma, Mwumvaneza; Kayitesi, Catherine; Gwiza, Aimé; Ruton, Hinda; Koleros, Andrew; Gupta, Neil; Balisanga, Helene; Riedel, David J; Nsanzimana, Sabin

    2015-10-01

    HIV prevalence is disproportionately high among female sex workers compared to the general population. Many African countries lack useful data on the size of female sex worker populations to inform national HIV programmes. A female sex worker size estimation exercise using three different venue-based methodologies was conducted among female sex workers in all provinces of Rwanda in August 2010. The female sex worker national population size was estimated using capture-recapture and enumeration methods, and the multiplier method was used to estimate the size of the female sex worker population in Kigali. A structured questionnaire was also used to supplement the data. The estimated number of female sex workers by the capture-recapture method was 3205 (95% confidence interval: 2998-3412). The female sex worker size was estimated at 3348 using the enumeration method. In Kigali, the female sex worker size was estimated at 2253 (95% confidence interval: 1916-2524) using the multiplier method. Nearly 80% of all female sex workers in Rwanda were found to be based in the capital, Kigali. This study provided a first-time estimate of the female sex worker population size in Rwanda using capture-recapture, enumeration, and multiplier methods. The capture-recapture and enumeration methods provided similar estimates of female sex worker in Rwanda. Combination of such size estimation methods is feasible and productive in low-resource settings and should be considered vital to inform national HIV programmes. © The Author(s) 2015.

  10. A Population-Based Clinical Trial of Irinotecan and Carboplatin

    Directory of Open Access Journals (Sweden)

    Derick Lau

    2009-01-01

    Full Text Available Purpose. Phase I trials of anticancer drugs are commonly conducted using the method of modified Fibonacci. We have developed a population-based design for phase I trials of combining anticancer drugs such as irinotecan and carboplatin. Patients and Methods. Intrapatient dose escalation of irinotecan and carboplatin was performed according to a predetermined schema to reach individual dose-limiting toxicity (DLT in 50 patients with solid tumors refractory to previous chemotherapy. The individual toxicity-limiting dose levels were analyzed for normal distribution using the method of Ryan-Joiner and subsequently used to determine a population-based maximum tolerated dose (pMTD. For comparison, a simulation study was performed using the method of modified Fibonacci. Results. The most common dose-limiting toxicities (DLTs included neutropenia (58%, thrombocytopenia (16%, and diarrhea (8%. The frequency of individual toxicity-limiting dose levels of 50 patients approximated a normal distribution. The dose levels associated with individual limiting toxicities ranged from level 1 (irinotecan 100 mg/m2 and carboplatin AUC = 4 mg/mL x min to level 8 (irinotecan 350 mg/m2 and carboplatin AUC = 6. The pMTD was determined to be dose level 3 (150 mg/m2 for irinotecan and AUC = 5 for carboplatin. In contrast, the MTD was determined to be dose level 4 (200 mg/m2 for irinotecan and AUC 5 for carboplatin by modified-Fibonacci simulation. Conclusions. The population-based design of phase I trial allows optimization of dose intensity and derivation of a pMTD. The pMTD has been applied in phase II trial of irinotecan and carboplatin in patients with small-cell lung cancer.

  11. Age- and Gender-Based Populations

    Science.gov (United States)

    ... population increases the risks of cognitive decline and suicide. About 25% of older adults have some type of mental health problem, such as a mood disorder not associated with normal aging. Older adults with ...

  12. Activity – based costing method

    Directory of Open Access Journals (Sweden)

    Èuchranová Katarína

    2001-06-01

    Full Text Available Activity based costing is a method of identifying and tracking the operating costs directly associated with processing items. It is the practice of focusing on some unit of output, such as a purchase order or an assembled automobile and attempting to determine its total as precisely as poccible based on the fixed and variable costs of the inputs.You use ABC to identify, quantify and analyze the various cost drivers (such as labor, materials, administrative overhead, rework. and to determine which ones are candidates for reduction.A processes any activity that accepts inputs, adds value to these inputs for customers and produces outputs for these customers. The customer may be either internal or external to the organization. Every activity within an organization comprimes one or more processes. Inputs, controls and resources are all supplied to the process.A process owner is the person responsible for performing and or controlling the activity.The direction of cost through their contact to partial activity and processes is a new modern theme today. Beginning of this method is connected with very important changes in the firm processes.ABC method is a instrument , that bring a competitive advantages for the firm.

  13. Regression Discontinuity Designs Based on Population Thresholds

    DEFF Research Database (Denmark)

    Eggers, Andrew C.; Freier, Ronny; Grembi, Veronica

    In many countries, important features of municipal government (such as the electoral system, mayors' salaries, and the number of councillors) depend on whether the municipality is above or below arbitrary population thresholds. Several papers have used a regression discontinuity design (RDD...

  14. An alternative method for assessing early mortality in contemporary populations.

    Science.gov (United States)

    Wiley, A S; Pike, I L

    1998-11-01

    Biological anthropologists are interested in a population's early mortality rates for a variety of reasons. Early mortality (infant or juvenile) is of obvious importance to those interested in demography, but early mortality statistics are useful for life history analysis, paleodemography, and human adaptability studies, among others. In general, the form of mortality statistics is derived from demography, where chronological age is the gold standard for statistical calculation and comparison. However, there are numerous problems associated with the collection, analysis, and interpretation of early mortality statistics based on age, particularly for anthropological research, which is often conducted in small or non-calendrical-age numerate populations. The infant mortality rate (IMR), for example, is notoriously difficult to determine in populations where accurate accounting of age is not routine, and yet it is widely used in demography, public health, medicine, and social science research. Here we offer an alternative to age-based early mortality statistics that makes use of human biologists' interest in, and skill at, assessing human growth and development. Our proposal is to use developmental stages of juveniles instead of relying exclusively on age as the basis for mortality statistics. Death or survival according to a developmental stage (such as crawling or weaning) may provide more accurate data that are also more closely related to the cause of death. Developmental stages have the added advantage of putting infants and children back at the center of the discussion of early mortality by focusing on their activities in relation to their environment. A case study from the Turkana population of Kenya illustrates the use of developmental stages in describing early mortality.

  15. Lattice Boltzmann method with the cell-population equilibrium

    International Nuclear Information System (INIS)

    Zhou Xiaoyang; Cheng Bing; Shi Baochang

    2008-01-01

    The central problem of the lattice Boltzmann method (LBM) is to construct a discrete equilibrium. In this paper, a multi-speed 1D cell-model of Boltzmann equation is proposed, in which the cell-population equilibrium, a direct non-negative approximation to the continuous Maxwellian distribution, plays an important part. By applying the explicit one-order Chapman–Enskog distribution, the model reduces the transportation and collision, two basic evolution steps in LBM, to the transportation of the non-equilibrium distribution. Furthermore, 1D dam-break problem is performed and the numerical results agree well with the analytic solutions

  16. Population-based treatment and outcomes of Stage I uterine serous carcinoma

    NARCIS (Netherlands)

    Putten, L.J.M. van der; Hoskins, P.; Tinker, A.; Lim, P.; Aquino-Parsons, C.; Kwon, J.S.

    2014-01-01

    OBJECTIVE: Uterine serous carcinoma (USC) is a rare type of endometrial cancer that often recurs in patients with Stage I disease. Our objective was to evaluate treatment and outcomes in Stage I USC in the context of a population-based study. METHODS: This was a population-based retrospective cohort

  17. Cardiovascular Disease Risk in a Large, Population-Based Cohort of Breast Cancer Survivors

    NARCIS (Netherlands)

    Boekel, Naomi B.; Schaapveld, Michael; Gietema, Jourik A.; Russell, Nicola S.; Poortmans, Philip; Theuws, Jacqueline C. M.; Schinagl, Dominic A. X.; Rietveld, Derek H. F.; Versteegh, Michel I. M.; Visser, Otto; Rutgers, Emiel J. T.; Aleman, Berthe M. P.; van Leeuwen, Flora E.

    2016-01-01

    Purpose: To conduct a large, population-based study on cardiovascular disease (CVD) in breast cancer (BC) survivors treated in 1989 or later. Methods and Materials: A large, population-based cohort comprising 70,230 surgically treated stage I to III BC patients diagnosed before age 75 years between

  18. Model-based estimation of finite population total in stratified sampling

    African Journals Online (AJOL)

    The work presented in this paper concerns the estimation of finite population total under model – based framework. Nonparametric regression approach as a method of estimating finite population total is explored. The asymptotic properties of the estimators based on nonparametric regression are also developed under ...

  19. Development and evaluation of a new method for sampling and monitoring the symphylid population in pineapple.

    Science.gov (United States)

    Soler, Alain; Gaude, Jean-Marie; Marie-Alphonsine, Paul-Alex; Vinatier, Fabrice; Dole, Bernard; Govindin, Jean-Claude; Fournier, Patrick; Queneherve, Patrick

    2011-09-01

    Symphylids (Hanseniella sp.) are polyphagous soilborne parasites. Today, symphylid populations on pineapple are monitored by observing root symptoms and the presence of symphylids at the bottom of basal leaves. The authors developed a reliable method with a bait and trap device to monitor symphylid populations in pineapple or fallow crops. The spatial distribution of the symphylid populations was evaluated using the variance/mean ratios and spatial analyses based on Moran's and Geary's indices. The method has been tested to monitor symphylid populations at different developmental stages of pineapple. Adding potato baits to the soil samples increased the trapping efficiency of symphylids when compared with 'soil only' and 'bait only' methods. The handling of the samples is also facilitated by the new device. Results showed that the vertical distribution of symphylids may be uniform deeply inside the soil profile under pineapple, up to 50 cm. Results showed that symphylid populations are highly aggregated, showing a spot area about 4-6 m wide for their development. The new method allows better and easier evaluation of symphylid populations. It may be very useful in the evaluation of new IPM methods to control symphylids under pineapple. Copyright © 2011 Society of Chemical Industry.

  20. Population-based absolute risk estimation with survey data

    Science.gov (United States)

    Kovalchik, Stephanie A.; Pfeiffer, Ruth M.

    2013-01-01

    Absolute risk is the probability that a cause-specific event occurs in a given time interval in the presence of competing events. We present methods to estimate population-based absolute risk from a complex survey cohort that can accommodate multiple exposure-specific competing risks. The hazard function for each event type consists of an individualized relative risk multiplied by a baseline hazard function, which is modeled nonparametrically or parametrically with a piecewise exponential model. An influence method is used to derive a Taylor-linearized variance estimate for the absolute risk estimates. We introduce novel measures of the cause-specific influences that can guide modeling choices for the competing event components of the model. To illustrate our methodology, we build and validate cause-specific absolute risk models for cardiovascular and cancer deaths using data from the National Health and Nutrition Examination Survey. Our applications demonstrate the usefulness of survey-based risk prediction models for predicting health outcomes and quantifying the potential impact of disease prevention programs at the population level. PMID:23686614

  1. DNA-based methods of geochemical prospecting

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, Matthew [Mill Valley, CA

    2011-12-06

    The present invention relates to methods for performing surveys of the genetic diversity of a population. The invention also relates to methods for performing genetic analyses of a population. The invention further relates to methods for the creation of databases comprising the survey information and the databases created by these methods. The invention also relates to methods for analyzing the information to correlate the presence of nucleic acid markers with desired parameters in a sample. These methods have application in the fields of geochemical exploration, agriculture, bioremediation, environmental analysis, clinical microbiology, forensic science and medicine.

  2. Bayesian data analysis in population ecology: motivations, methods, and benefits

    Science.gov (United States)

    Dorazio, Robert

    2016-01-01

    During the 20th century ecologists largely relied on the frequentist system of inference for the analysis of their data. However, in the past few decades ecologists have become increasingly interested in the use of Bayesian methods of data analysis. In this article I provide guidance to ecologists who would like to decide whether Bayesian methods can be used to improve their conclusions and predictions. I begin by providing a concise summary of Bayesian methods of analysis, including a comparison of differences between Bayesian and frequentist approaches to inference when using hierarchical models. Next I provide a list of problems where Bayesian methods of analysis may arguably be preferred over frequentist methods. These problems are usually encountered in analyses based on hierarchical models of data. I describe the essentials required for applying modern methods of Bayesian computation, and I use real-world examples to illustrate these methods. I conclude by summarizing what I perceive to be the main strengths and weaknesses of using Bayesian methods to solve ecological inference problems.

  3. Discontinuous Galerkin finite element method for solving population density functions of cortical pyramidal and thalamic neuronal populations.

    Science.gov (United States)

    Huang, Chih-Hsu; Lin, Chou-Ching K; Ju, Ming-Shaung

    2015-02-01

    Compared with the Monte Carlo method, the population density method is efficient for modeling collective dynamics of neuronal populations in human brain. In this method, a population density function describes the probabilistic distribution of states of all neurons in the population and it is governed by a hyperbolic partial differential equation. In the past, the problem was mainly solved by using the finite difference method. In a previous study, a continuous Galerkin finite element method was found better than the finite difference method for solving the hyperbolic partial differential equation; however, the population density function often has discontinuity and both methods suffer from a numerical stability problem. The goal of this study is to improve the numerical stability of the solution using discontinuous Galerkin finite element method. To test the performance of the new approach, interaction of a population of cortical pyramidal neurons and a population of thalamic neurons was simulated. The numerical results showed good agreement between results of discontinuous Galerkin finite element and Monte Carlo methods. The convergence and accuracy of the solutions are excellent. The numerical stability problem could be resolved using the discontinuous Galerkin finite element method which has total-variation-diminishing property. The efficient approach will be employed to simulate the electroencephalogram or dynamics of thalamocortical network which involves three populations, namely, thalamic reticular neurons, thalamocortical neurons and cortical pyramidal neurons. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Comparison of Three Plot Selection Methods for Estimating Change in Temporally Variable, Spatially Clustered Populations.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, William L. [Bonneville Power Administration, Portland, OR (US). Environment, Fish and Wildlife

    2001-07-01

    Monitoring population numbers is important for assessing trends and meeting various legislative mandates. However, sampling across time introduces a temporal aspect to survey design in addition to the spatial one. For instance, a sample that is initially representative may lose this attribute if there is a shift in numbers and/or spatial distribution in the underlying population that is not reflected in later sampled plots. Plot selection methods that account for this temporal variability will produce the best trend estimates. Consequently, I used simulation to compare bias and relative precision of estimates of population change among stratified and unstratified sampling designs based on permanent, temporary, and partial replacement plots under varying levels of spatial clustering, density, and temporal shifting of populations. Permanent plots produced more precise estimates of change than temporary plots across all factors. Further, permanent plots performed better than partial replacement plots except for high density (5 and 10 individuals per plot) and 25% - 50% shifts in the population. Stratified designs always produced less precise estimates of population change for all three plot selection methods, and often produced biased change estimates and greatly inflated variance estimates under sampling with partial replacement. Hence, stratification that remains fixed across time should be avoided when monitoring populations that are likely to exhibit large changes in numbers and/or spatial distribution during the study period. Key words: bias; change estimation; monitoring; permanent plots; relative precision; sampling with partial replacement; temporary plots.

  5. Error baseline rates of five sample preparation methods used to characterize RNA virus populations.

    Directory of Open Access Journals (Sweden)

    Jeffrey R Kugelman

    Full Text Available Individual RNA viruses typically occur as populations of genomes that differ slightly from each other due to mutations introduced by the error-prone viral polymerase. Understanding the variability of RNA virus genome populations is critical for understanding virus evolution because individual mutant genomes may gain evolutionary selective advantages and give rise to dominant subpopulations, possibly even leading to the emergence of viruses resistant to medical countermeasures. Reverse transcription of virus genome populations followed by next-generation sequencing is the only available method to characterize variation for RNA viruses. However, both steps may lead to the introduction of artificial mutations, thereby skewing the data. To better understand how such errors are introduced during sample preparation, we determined and compared error baseline rates of five different sample preparation methods by analyzing in vitro transcribed Ebola virus RNA from an artificial plasmid-based system. These methods included: shotgun sequencing from plasmid DNA or in vitro transcribed RNA as a basic "no amplification" method, amplicon sequencing from the plasmid DNA or in vitro transcribed RNA as a "targeted" amplification method, sequence-independent single-primer amplification (SISPA as a "random" amplification method, rolling circle reverse transcription sequencing (CirSeq as an advanced "no amplification" method, and Illumina TruSeq RNA Access as a "targeted" enrichment method. The measured error frequencies indicate that RNA Access offers the best tradeoff between sensitivity and sample preparation error (1.4-5 of all compared methods.

  6. AMOVA-based clustering of population genetic data

    NARCIS (Netherlands)

    Meirmans, P.G.

    2012-01-01

    Determining the genetic structure of populations is becoming an increasingly important aspect of genetic studies. One of the most frequently used methods is the calculation of F-statistics using an Analysis of Molecular Variance (AMOVA). However, this has the drawback that the population hierarchy

  7. Bacterial population in traditional sourdough evaluated by molecular methods.

    Science.gov (United States)

    Randazzo, C L; Heilig, H; Restuccia, C; Giudici, P; Caggia, C

    2005-01-01

    To study the microbial communities in artisanal sourdoughs, manufactured by traditional procedure in different areas of Sicily, and to evaluate the lactic acid bacteria (LAB) population by classical and culture-independent approaches. Forty-five LAB isolates were identified both by phenotypic and molecular methods. The restriction fragment length polymorphism and 16S ribosomal DNA gene sequencing gave evidence of a variety of species with the dominance of Lactobacillus sanfranciscensis and Lactobacillus pentosus, in all sourdoughs tested. Culture-independent method, such as denaturing gradient gel electrophoresis (DGGE) of the V6-V8 regions of the 16S rDNA, was applied for microbial community fingerprint. The DGGE profiles revealed the dominance of L. sanfranciscensis species. In addition, Lactobacillus-specific primers were used to amplify the V1-V3 regions of the 16S rDNA. DGGE profiles flourished the dominance of L. sanfranciscensis and Lactobacillus fermentum in the traditional sourdoughs, and revealed that the closely related species Lactobacillus kimchii and Lactobacillus alimentarius were not discriminated. Lactobacillus-specific PCR-DGGE analysis is a rapid tool for rapid detection of Lactobacillus species in artisanal sourdough. This study reports a characterization of Lactobacillus isolates from artisanal sourdoughs and highlights the value of DGGE approach to detect uncultivable Lactobacillus species.

  8. Use and misuse of mixed methods in population oral health research: A scoping review.

    Science.gov (United States)

    Gupta, A; Keuskamp, D

    2018-05-30

    Despite the known benefits of a mixed methods approach in health research, little is known of its use in the field of population oral health. To map the extent of literature using a mixed methods approach to examine population oral health outcomes. For a comprehensive search of all the available literature published in the English language, databases including PubMed, Dentistry and Oral Sciences Source (DOSS), CINAHL, Web of Science and EMBASE (including Medline) were searched using a range of keywords from inception to October 2017. Only peer-reviewed, population-based studies of oral health outcomes conducted among non-institutionalised participants and using mixed methods were considered eligible for inclusion. Only nine studies met the inclusion criteria and were included in the review. The most frequent oral health outcome investigated was caries experience. However, most studies lacked a theoretical rationale or framework for using mixed methods, or supporting the use of qualitative data. Concurrent triangulation with a convergent design was the most commonly used mixed methods typology for integrating quantitative and qualitative data. The tools used to collect quantitative and qualitative data were mostly limited to surveys and interviews. With growing complexity recognised in the determinants of oral disease, future studies addressing population oral health outcomes are likely to benefit from the use of mixed methods. Explicit consideration of theoretical framework and methodology will strengthen those investigations. Copyright© 2018 Dennis Barber Ltd.

  9. Demographic Models for Projecting Population and Migration: Methods for African Historical Analysis

    Directory of Open Access Journals (Sweden)

    Patrick Manning

    2015-08-01

    Full Text Available This study presents methods for projecting population and migration over time in cases were empirical data are missing or undependable. The methods are useful for cases in which the researcher has details of population size and structure for a limited period of time (most obviously, the end point, with scattered evidence on other times. It enables estimation of population size, including its structure in age, sex, and status, either forward or backward in time. The program keeps track of all the details. The calculated data can be reported or sampled and compared to empirical findings at various times and places to expected values based on other procedures of estimation. The application of these general methods that is developed here is the projection of African populations backwards in time from 1950, since 1950 is the first date for which consistently strong demographic estimates are available for national-level populations all over the African continent. The models give particular attention to migration through enslavement, which was highly important in Africa from 1650 to 1900. Details include a sensitivity analysis showing relative significance of input variables and techniques for calibrating various dimensions of the projection with each other. These same methods may be applicable to quite different historical situations, as long as the data conform in structure to those considered here.

  10. Chapter 11. Community analysis-based methods

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Y.; Wu, C.H.; Andersen, G.L.; Holden, P.A.

    2010-05-01

    Microbial communities are each a composite of populations whose presence and relative abundance in water or other environmental samples are a direct manifestation of environmental conditions, including the introduction of microbe-rich fecal material and factors promoting persistence of the microbes therein. As shown by culture-independent methods, different animal-host fecal microbial communities appear distinctive, suggesting that their community profiles can be used to differentiate fecal samples and to potentially reveal the presence of host fecal material in environmental waters. Cross-comparisons of microbial communities from different hosts also reveal relative abundances of genetic groups that can be used to distinguish sources. In increasing order of their information richness, several community analysis methods hold promise for MST applications: phospholipid fatty acid (PLFA) analysis, denaturing gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism (TRFLP), cloning/sequencing, and PhyloChip. Specific case studies involving TRFLP and PhyloChip approaches demonstrate the ability of community-based analyses of contaminated waters to confirm a diagnosis of water quality based on host-specific marker(s). The success of community-based MST for comprehensively confirming fecal sources relies extensively upon using appropriate multivariate statistical approaches. While community-based MST is still under evaluation and development as a primary diagnostic tool, results presented herein demonstrate its promise. Coupled with its inherently comprehensive ability to capture an unprecedented amount of microbiological data that is relevant to water quality, the tools for microbial community analysis are increasingly accessible, and community-based approaches have unparalleled potential for translation into rapid, perhaps real-time, monitoring platforms.

  11. Population-based study on use of chemotherapy in men with castration resistant prostate cancer

    OpenAIRE

    Lissbrant, Ingela Franck; Garmo, Hans; Widmark, Anders; Stattin, P?r

    2013-01-01

    Background. Chemotherapy prolongs life and relieves symptoms in men with castration resistant prostate cancer (CRPC). There is limited information on a population level on the use of chemotherapy for CRPC. Material and methods. To assess the use of chemotherapy in men with CRPC we conducted a register-based nationwide population-based study in Prostate Cancer data Base Sweden (PCBaSe) and a nationwide in-patient drug register (SALT database) between May 2009 and December 2010. We assumed that...

  12. GIS-based poverty and population distribution analysis in China

    Science.gov (United States)

    Cui, Jing; Wang, Yingjie; Yan, Hong

    2009-07-01

    Geographically, poverty status is not only related with social-economic factors but also strongly affected by geographical environment. In the paper, GIS-based poverty and population distribution analysis method is introduced for revealing their regional differences. More than 100000 poor villages and 592 national key poor counties are chosen for the analysis. The results show that poverty distribution tends to concentrate in most of west China and mountainous rural areas of mid China. Furthermore, the fifth census data are overlaid to those poor areas in order to gain its internal diversity of social-economic characteristics. By overlaying poverty related social-economic parameters, such as sex ratio, illiteracy, education level, percentage of ethnic minorities, family composition, finding shows that poverty distribution is strongly correlated with high illiteracy rate, high percentage minorities, and larger family member.

  13. Childhood blindness in India: a population based perspective

    Science.gov (United States)

    Dandona, R; Dandona, L

    2003-01-01

    Aim: To estimate the prevalence and causes of blindness in children in the southern Indian state of Andhra Pradesh. Methods: These data were obtained as part of two population based studies in which 6935 children ≤15 years of age participated. Blindness was defined as presenting distance visual acuity <6/60 in the better eye. Results: The prevalence of childhood blindness was 0.17% (95% confidence interval 0.09 to 0.30). Treatable refractive error caused 33.3% of the blindness, followed by 16.6% due to preventable causes (8.3% each due to vitamin A deficiency and amblyopia after cataract surgery). The major causes of the remaining blindness included congenital eye anomalies (16.7%) and retinal degeneration (16.7%). Conclusion: In the context of Vision 2020, the priorities for action to reduce childhood blindness in India are refractive error, cataract related amblyopia, and corneal diseases. PMID:12598433

  14. A population-based prospective study of optic neuritis

    DEFF Research Database (Denmark)

    Soelberg, K; Jarius, S; Skejoe, Hanne Pernille Bro

    2017-01-01

    BACKGROUND: Optic neuritis (ON) is often associated with multiple sclerosis (MS). Early diagnosis is critical to optimal patient management. OBJECTIVE: To estimate the incidence of acute ON and the rates of conversion to MS and antibody-mediated ON. METHOD: Population-based prospective study......-specific incidence was 3.28 (2.44-4.31) per 100,000 person years, 2.02 for men and 4.57 for women. At follow-up, 20 patients met the diagnostic criteria for MS, MRI lesions disseminated in space and time in 17/20 patients. AQP4-IgG was detected in none, MOG-IgG was detected in two patients. CONCLUSION...

  15. Harmonising measures of knee and hip osteoarthritis in population-based cohort studies

    DEFF Research Database (Denmark)

    Leyland, K M; Gates, L S; Nevitt, M

    2018-01-01

    OBJECTIVE: Population-based osteoarthritis (OA) cohorts provide vital data on risk factors and outcomes of OA, however the methods to define OA vary between cohorts. We aimed to provide recommendations for combining knee and hip OA data in extant and future population cohort studies, in order to ...

  16. Epidemiology of Haemophilus influenzae bacteremia: A multi-national population-based assessment

    DEFF Research Database (Denmark)

    Laupland, Kevin B; Schønheyder, Henrik C; Østergaard, Christian

    2011-01-01

    OBJECTIVES: Haemophilus influenzae is an important cause of invasive infection but contemporary data in non-selected populations is limited. METHODS: Population-based surveillance for Haemophilus influenzae bacteremia was conducted in seven regions in Australia, Canada, and Denmark during 2000-20...

  17. PINP: a new method of tagging neuronal populations for identification during in vivo electrophysiological recording.

    Directory of Open Access Journals (Sweden)

    Susana Q Lima

    Full Text Available Neural circuits are exquisitely organized, consisting of many different neuronal subpopulations. However, it is difficult to assess the functional roles of these subpopulations using conventional extracellular recording techniques because these techniques do not easily distinguish spikes from different neuronal populations. To overcome this limitation, we have developed PINP (Photostimulation-assisted Identification of Neuronal Populations, a method of tagging neuronal populations for identification during in vivo electrophysiological recording. The method is based on expressing the light-activated channel channelrhodopsin-2 (ChR2 to restricted neuronal subpopulations. ChR2-tagged neurons can be detected electrophysiologically in vivo since illumination of these neurons with a brief flash of blue light triggers a short latency reliable action potential. We demonstrate the feasibility of this technique by expressing ChR2 in distinct populations of cortical neurons using two different strategies. First, we labeled a subpopulation of cortical neurons-mainly fast-spiking interneurons-by using adeno-associated virus (AAV to deliver ChR2 in a transgenic mouse line in which the expression of Cre recombinase was driven by the parvalbumin promoter. Second, we labeled subpopulations of excitatory neurons in the rat auditory cortex with ChR2 based on projection target by using herpes simplex virus 1 (HSV1, which is efficiently taken up by axons and transported retrogradely; we find that this latter population responds to acoustic stimulation differently from unlabeled neurons. Tagging neurons is a novel application of ChR2, used in this case to monitor activity instead of manipulating it. PINP can be readily extended to other populations of genetically identifiable neurons, and will provide a useful method for probing the functional role of different neuronal populations in vivo.

  18. A nodal method based on matrix-response method

    International Nuclear Information System (INIS)

    Rocamora Junior, F.D.; Menezes, A.

    1982-01-01

    A nodal method based in the matrix-response method, is presented, and its application to spatial gradient problems, such as those that exist in fast reactors, near the core - blanket interface, is investigated. (E.G.) [pt

  19. Searching for rigour in the reporting of mixed methods population health research: a methodological review.

    Science.gov (United States)

    Brown, K M; Elliott, S J; Leatherdale, S T; Robertson-Wilson, J

    2015-12-01

    The environments in which population health interventions occur shape both their implementation and outcomes. Hence, when evaluating these interventions, we must explore both intervention content and context. Mixed methods (integrating quantitative and qualitative methods) provide this opportunity. However, although criteria exist for establishing rigour in quantitative and qualitative research, there is poor consensus regarding rigour in mixed methods. Using the empirical example of school-based obesity interventions, this methodological review examined how mixed methods have been used and reported, and how rigour has been addressed. Twenty-three peer-reviewed mixed methods studies were identified through a systematic search of five databases and appraised using the guidelines for Good Reporting of a Mixed Methods Study. In general, more detailed description of data collection and analysis, integration, inferences and justifying the use of mixed methods is needed. Additionally, improved reporting of methodological rigour is required. This review calls for increased discussion of practical techniques for establishing rigour in mixed methods research, beyond those for quantitative and qualitative criteria individually. A guide for reporting mixed methods research in population health should be developed to improve the reporting quality of mixed methods studies. Through improved reporting, mixed methods can provide strong evidence to inform policy and practice. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Interim Feed The Future Population Based Assessment of Cambodia

    Data.gov (United States)

    US Agency for International Development — This is the interim population based survey of Feed the Future in Cambodia for 2015. The data is split into survey modules. Modules A through C includes location...

  1. Development of a Population Balance Model of a pharmaceutical drying process and testing of solution methods

    DEFF Research Database (Denmark)

    Mortier, Séverine Thérèse F.C.; Gernaey, Krist; De Beer, Thomas

    2013-01-01

    Drying is frequently used in the production of pharmaceutical tablets. Simulation-based control strategy development for such a drying process requires a detailed model. First, the drying of wet granules is modelled using a Population Balance Model. A growth term based on a reduced model was used......, which describes the decrease of the moisture content, to follow the moisture content distribution for a batch of granules. Secondly, different solution methods for solving the PBM are compared. The effect of grid size (discretization methods) is analyzed in terms of accuracy and calculation time. All...

  2. [Bases and methods of suturing].

    Science.gov (United States)

    Vogt, P M; Altintas, M A; Radtke, C; Meyer-Marcotty, M

    2009-05-01

    If pharmaceutic modulation of scar formation does not improve the quality of the healing process over conventional healing, the surgeon must rely on personal skill and experience. Therefore a profound knowledge of wound healing based on experimental and clinical studies supplemented by postsurgical means of scar management and basic techniques of planning incisions, careful tissue handling, and thorough knowledge of suturing remain the most important ways to avoid abnormal scarring. This review summarizes the current experimental and clinical bases of surgical scar management.

  3. Managing incidental findings in population based biobank research

    Directory of Open Access Journals (Sweden)

    Berge Solberg

    2012-04-01

    Full Text Available With the introduction of whole genome sequencing in medical research, the debate on how to handle incidental findings is becoming omnipresent. Much of the literature on the topic so far, seems to defend the researcher’s duty to inform, the participant’s right to know combined with a thorough informed consent in order to protect and secure high ethical standards in research. In this paper, we argue that this ethical response to incidental findings and whole genome sequencing is appropriate in a clinical context, in what we call therapeutic research. However, we further argue, that it is rather inappropriate in basic research, like the research going on in public health oriented population based biobanks. Our argument is based on two premises: First, in population based biobank research the duties and rights involved are radically different from a clinical based setting. Second, to introduce the ethical framework from the clinical setting into population based basic research, is not only wrong, but it may lead to unethical consequences. A Norwegian population based biobank and the research-ethical debate in Norway on the regulation of whole genome sequencing is used as an illustrative case to demonstrate the pitfalls when approaching the debate on incidental findings in population based biobank research.

  4. A statistical method for testing epidemiological results, as applied to the Hanford worker population

    International Nuclear Information System (INIS)

    Brodsky, A.

    1979-01-01

    Some recent reports of Mancuso, Stewart and Kneale claim findings of radiation-produced cancer in the Hanford worker population. These claims are based on statistical computations that use small differences in accumulated exposures between groups dying of cancer and groups dying of other causes; actual mortality and longevity were not reported. This paper presents a statistical method for evaluation of actual mortality and longevity longitudinally over time, as applied in a primary analysis of the mortality experience of the Hanford worker population. Although available, this method was not utilized in the Mancuso-Stewart-Kneale paper. The author's preliminary longitudinal analysis shows that the gross mortality experience of persons employed at Hanford during 1943-70 interval did not differ significantly from that of certain controls, when both employees and controls were selected from families with two or more offspring and comparison were matched by age, sex, race and year of entry into employment. This result is consistent with findings reported by Sanders (Health Phys. vol.35, 521-538, 1978). The method utilizes an approximate chi-square (1 D.F.) statistic for testing population subgroup comparisons, as well as the cumulation of chi-squares (1 D.F.) for testing the overall result of a particular type of comparison. The method is available for computer testing of the Hanford mortality data, and could also be adapted to morbidity or other population studies. (author)

  5. Based on Penalty Function Method

    Directory of Open Access Journals (Sweden)

    Ishaq Baba

    2015-01-01

    Full Text Available The dual response surface for simultaneously optimizing the mean and variance models as separate functions suffers some deficiencies in handling the tradeoffs between bias and variance components of mean squared error (MSE. In this paper, the accuracy of the predicted response is given a serious attention in the determination of the optimum setting conditions. We consider four different objective functions for the dual response surface optimization approach. The essence of the proposed method is to reduce the influence of variance of the predicted response by minimizing the variability relative to the quality characteristics of interest and at the same time achieving the specific target output. The basic idea is to convert the constraint optimization function into an unconstraint problem by adding the constraint to the original objective function. Numerical examples and simulations study are carried out to compare performance of the proposed method with some existing procedures. Numerical results show that the performance of the proposed method is encouraging and has exhibited clear improvement over the existing approaches.

  6. COMPANY VALUATION METHODS BASED ON PATRIMONY

    Directory of Open Access Journals (Sweden)

    SUCIU GHEORGHE

    2013-02-01

    Full Text Available The methods used for the company valuation can be divided into 3 main groups: methods based on patrimony,methods based on financial performance, methods based both on patrimony and on performance. The companyvaluation methods based on patrimony are implemented taking into account the balance sheet or the financialstatement. The financial statement refers to that type of balance in which the assets are arranged according to liquidity,and the liabilities according to their financial maturity date. The patrimonial methods are based on the principle thatthe value of the company equals that of the patrimony it owns. From a legal point of view, the patrimony refers to allthe rights and obligations of a company. The valuation of companies based on their financial performance can be donein 3 ways: the return value, the yield value, the present value of the cash flows. The mixed methods depend both onpatrimony and on financial performance or can make use of other methods.

  7. Scleroderma prevalence: demographic variations in a population-based sample.

    Science.gov (United States)

    Bernatsky, S; Joseph, L; Pineau, C A; Belisle, P; Hudson, M; Clarke, A E

    2009-03-15

    To estimate the prevalence of systemic sclerosis (SSc) using population-based administrative data, and to assess the sensitivity of case ascertainment approaches. We ascertained SSc cases from Quebec physician billing and hospitalization databases (covering approximately 7.5 million individuals). Three case definition algorithms were compared, and statistical methods accounting for imperfect case ascertainment were used to estimate SSc prevalence and case ascertainment sensitivity. A hierarchical Bayesian latent class regression model that accounted for possible between-test dependence conditional on disease status estimated the effect of patient characteristics on SSc prevalence and the sensitivity of the 3 ascertainment algorithms. Accounting for error inherent in both the billing and the hospitalization data, we estimated SSc prevalence in 2003 at 74.4 cases per 100,000 women (95% credible interval [95% CrI] 69.3-79.7) and 13.3 cases per 100,000 men (95% CrI 11.1-16.1). Prevalence was higher for older individuals, particularly in urban women (161.2 cases per 100,000, 95% CrI 148.6-175.0). Prevalence was lowest in young men (in rural areas, as low as 2.8 cases per 100,000, 95% CrI 1.4-4.8). In general, no single algorithm was very sensitive, with point estimates for sensitivity ranging from 20-73%. We found marked differences in SSc prevalence according to age, sex, and region. In general, no single case ascertainment approach was very sensitive for SSc. Therefore, using data from multiple sources, with adjustment for the imperfect nature of each, is an important strategy in population-based studies of SSc and similar conditions.

  8. Estimating glomerular filtration rate in a population-based study

    Directory of Open Access Journals (Sweden)

    Anoop Shankar

    2010-07-01

    Full Text Available Anoop Shankar1, Kristine E Lee2, Barbara EK Klein2, Paul Muntner3, Peter C Brazy4, Karen J Cruickshanks2,5, F Javier Nieto5, Lorraine G Danforth2, Carla R Schubert2,5, Michael Y Tsai6, Ronald Klein21Department of Community Medicine, West Virginia University School of Medicine, Morgantown, WV, USA; 2Department of Ophthalmology and Visual Sciences, 4Department of Medicine, 5Department of Population Health Sciences, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA; 3Department of Community Medicine, Mount Sinai School of Medicine, NY, USA; 6Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USABackground: Glomerular filtration rate (GFR-estimating equations are used to determine the prevalence of chronic kidney disease (CKD in population-based studies. However, it has been suggested that since the commonly used GFR equations were originally developed from samples of patients with CKD, they underestimate GFR in healthy populations. Few studies have made side-by-side comparisons of the effect of various estimating equations on the prevalence estimates of CKD in a general population sample.Patients and methods: We examined a population-based sample comprising adults from Wisconsin (age, 43–86 years; 56% women. We compared the prevalence of CKD, defined as a GFR of <60 mL/min per 1.73 m2 estimated from serum creatinine, by applying various commonly used equations including the modification of diet in renal disease (MDRD equation, Cockcroft–Gault (CG equation, and the Mayo equation. We compared the performance of these equations against the CKD definition of cystatin C >1.23 mg/L.Results: We found that the prevalence of CKD varied widely among different GFR equations. Although the prevalence of CKD was 17.2% with the MDRD equation and 16.5% with the CG equation, it was only 4.8% with the Mayo equation. Only 24% of those identified to have GFR in the range of 50–59 mL/min per 1

  9. A comparison of methods for calculating population exposure estimates of daily weather for health research

    Directory of Open Access Journals (Sweden)

    Dear Keith BG

    2006-09-01

    Full Text Available Abstract Background To explain the possible effects of exposure to weather conditions on population health outcomes, weather data need to be calculated at a level in space and time that is appropriate for the health data. There are various ways of estimating exposure values from raw data collected at weather stations but the rationale for using one technique rather than another; the significance of the difference in the values obtained; and the effect these have on a research question are factors often not explicitly considered. In this study we compare different techniques for allocating weather data observations to small geographical areas and different options for weighting averages of these observations when calculating estimates of daily precipitation and temperature for Australian Postal Areas. Options that weight observations based on distance from population centroids and population size are more computationally intensive but give estimates that conceptually are more closely related to the experience of the population. Results Options based on values derived from sites internal to postal areas, or from nearest neighbour sites – that is, using proximity polygons around weather stations intersected with postal areas – tended to include fewer stations' observations in their estimates, and missing values were common. Options based on observations from stations within 50 kilometres radius of centroids and weighting of data by distance from centroids gave more complete estimates. Using the geographic centroid of the postal area gave estimates that differed slightly from the population weighted centroids and the population weighted average of sub-unit estimates. Conclusion To calculate daily weather exposure values for analysis of health outcome data for small areas, the use of data from weather stations internal to the area only, or from neighbouring weather stations (allocated by the use of proximity polygons, is too limited. The most

  10. Anxiety disorders in young people: a population-based study

    Directory of Open Access Journals (Sweden)

    Thaíse Campos Mondin

    2013-12-01

    Full Text Available Objective: To assess the prevalence of anxiety disorders and associated factors in young adults. Methods: Cross-sectional population-based study of individuals between the ages of 18 and 24 years randomly selected from 89 census-based sectors to ensure an adequate sample size. Household selection within the sectors was performed according to a systematic sampling process. Anxiety disorders were assessed using the Mini International Neuropsychiatric Interview (MINI. The final sample comprised 1,560 young adults. Results: Of the participants who were diagnosed with anxiety disorders, 12.3% had agoraphobia, 9.7% had generalised anxiety disorder, 4.0% had social phobia, 3.3% had obsessive-compulsive disorder, 2.5% had panic disorder, and 2.1% had post-traumatic stress disorder; only 23.8% had received any previous treatment. Anxiety disorders were associated with sex, socioeconomic status, psychiatric problems in parents, alcohol abuse, and tobacco use. Conclusions: The identification of factors associated with anxiety disorders in young people enables us to develop intervention strategies. Anxiety disorders are not only highly prevalent but are also associated with significant functional impairment, significant reductions in quality of life, lower productivity, and higher rates of comorbidities.

  11. Constructing stage-structured matrix population models from life tables: comparison of methods

    Directory of Open Access Journals (Sweden)

    Masami Fujiwara

    2017-10-01

    for discounting the rate, was the best approach. However, stage-structured models performed poorly in estimating generation time, regardless of the methods used for constructing the models. Based on the results, we recommend using an age-structured matrix population model or the Euler-Lotka equation for calculating λ and generation time when life table data are available. Then, these age-structured vital rates can be converted into a stage-structured model for further analyses.

  12. Methods of estimating population exposures from Plowshare applications

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, S V; Rohwer, P S [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1969-07-01

    When estimating doses to populations it is necessary to divide the total population into groups that have parameters of similar type and magnitude in order to identify critical population groups. Age groups constitute the most basic and generally useful way of dividing the total population for estimating dose. Models for estimating dose, particularly the internal dose from inhalation and ingestion of radioactivity, should be written as a function of age. The importance of considering age-dependency is emphasized by the fact that some of the internal dose parameters change by much as a factor of ten for some radionuclides when comparing a one year old with an adult. A computer code called INREM has been written which can consider all internal dose parameters as a function of age. The major imitation in using this computer code for all radionuclides is the paucity of age-dependent input data for many radionuclides. Tritium, iodine, cesium, and strontium have been studied in detail with INREM and the results and interpretations are discussed. Another code, EXREM, computes the external dose rates and cumulative doses from both beta particles and gamma photons from submersion in a radioactive cloud, submersion in contaminated water and exposure above a contaminated land surface. This code can consider up to 25 Plowshare detonations and a variety of combinations for calculating doses and dose rates in relation to a detonation schedule. The importance of using both INREM and EXREM to estimate the total dose to a population group is stressed. (author)

  13. Methods of estimating population exposures from Plowshare applications

    International Nuclear Information System (INIS)

    Kaye, S.V.; Rohwer, P.S.

    1969-01-01

    When estimating doses to populations it is necessary to divide the total population into groups that have parameters of similar type and magnitude in order to identify critical population groups. Age groups constitute the most basic and generally useful way of dividing the total population for estimating dose. Models for estimating dose, particularly the internal dose from inhalation and ingestion of radioactivity, should be written as a function of age. The importance of considering age-dependency is emphasized by the fact that some of the internal dose parameters change by much as a factor of ten for some radionuclides when comparing a one year old with an adult. A computer code called INREM has been written which can consider all internal dose parameters as a function of age. The major imitation in using this computer code for all radionuclides is the paucity of age-dependent input data for many radionuclides. Tritium, iodine, cesium, and strontium have been studied in detail with INREM and the results and interpretations are discussed. Another code, EXREM, computes the external dose rates and cumulative doses from both beta particles and gamma photons from submersion in a radioactive cloud, submersion in contaminated water and exposure above a contaminated land surface. This code can consider up to 25 Plowshare detonations and a variety of combinations for calculating doses and dose rates in relation to a detonation schedule. The importance of using both INREM and EXREM to estimate the total dose to a population group is stressed. (author)

  14. Error baseline rates of five sample preparation methods used to characterize RNA virus populations

    Science.gov (United States)

    Kugelman, Jeffrey R.; Wiley, Michael R.; Nagle, Elyse R.; Reyes, Daniel; Pfeffer, Brad P.; Kuhn, Jens H.; Sanchez-Lockhart, Mariano; Palacios, Gustavo F.

    2017-01-01

    Individual RNA viruses typically occur as populations of genomes that differ slightly from each other due to mutations introduced by the error-prone viral polymerase. Understanding the variability of RNA virus genome populations is critical for understanding virus evolution because individual mutant genomes may gain evolutionary selective advantages and give rise to dominant subpopulations, possibly even leading to the emergence of viruses resistant to medical countermeasures. Reverse transcription of virus genome populations followed by next-generation sequencing is the only available method to characterize variation for RNA viruses. However, both steps may lead to the introduction of artificial mutations, thereby skewing the data. To better understand how such errors are introduced during sample preparation, we determined and compared error baseline rates of five different sample preparation methods by analyzing in vitro transcribed Ebola virus RNA from an artificial plasmid-based system. These methods included: shotgun sequencing from plasmid DNA or in vitro transcribed RNA as a basic “no amplification” method, amplicon sequencing from the plasmid DNA or in vitro transcribed RNA as a “targeted” amplification method, sequence-independent single-primer amplification (SISPA) as a “random” amplification method, rolling circle reverse transcription sequencing (CirSeq) as an advanced “no amplification” method, and Illumina TruSeq RNA Access as a “targeted” enrichment method. The measured error frequencies indicate that RNA Access offers the best tradeoff between sensitivity and sample preparation error (1.4−5) of all compared methods. PMID:28182717

  15. Population-based assessment of heartburn in urban Black Americans.

    Science.gov (United States)

    Friedenberg, F K; Makipour, K; Palit, A; Shah, S; Vanar, V; Richter, J E

    2013-08-01

    Prevalence data for heartburn in the urban Black American community is lacking. In order to estimate prevalence for this community, we analyzed data from an ongoing cohort study in progress at our hospital. Comprehensive interviews allowed for exploration of factors associated with heartburn. Complex, stratified sampling design was the method used. Survey invitations are hand-delivered to random blocks in a single zip code tabulation area. One member per eligible household is invited to complete a computer-based survey. Heartburn was defined as ≥ 3 days/week of symptoms as defined by the Montreal Definition and Classification of gastroesophageal reflux disease. Scaling and weighting factors were utilized to estimate population level prevalence. Multivariate logistic regression was used to identify independent predictor variables for heartburn. Enrolled 379 participants corresponding to a weighted sample size of 22,409 (20,888-23,930) citizens. Demographic characteristics of the sample closely matched those of the entire targeted population. Overall, the weighted prevalence of heartburn ≥ 3 times per week was 17.6% (16.4-18.8%). Variables independently associated with heartburn were body mass index, daily caloric and fat intake, diabetes mellitus (odds ratio = 2.95; 2.59-3.36), cigarette smoking, and alcohol consumption (odds ratio = 2.55; 2.25-2.89). Factors inversely associated included illicit drug use and increased physical activity. Waist : hip ratio showed no relationship. The prevalence of heartburn ≥ 3 times per week is high in the Black American community. Adverse lifestyle behaviors showed particularly important associations. Our study needs to be replicated in other communities with similar demographics. © 2012 Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

  16. Population structure of Angiostrongylus cantonensis (Nematoda: Metastrongylidae) in Thailand based on PCR-RAPD markers.

    Science.gov (United States)

    Thaenkham, Urusa; Pakdee, Wallop; Nuamtanong, Supaporn; Maipanich, Wanna; Pubampen, Somchit; Sa-Nguankiat, Surapol; Komalamisra, Chalit

    2012-05-01

    Angiostrongylus cantonensis is the causative agent of angiostrongyliasis, which is widely distributed throughout the world. It can specifically infect many species of intermediate and definitive hosts. This study examined the genetic differentiation and population structure using the RAPD-PCR method of parasites obtained from 8 different geographical areas of Thailand. Based on 8 primers, high levels of genetic diversity and low levels of gene flow among populations were found. Using genetic distance and neighbor-joining dendrogram methods, A. cantonensis in Thailand could be divided into two groups with statistically significant genetic differentiation of the two populations. However, genotypic variations and haplotype relationships need to be further elucidated using other markers.

  17. Recurrent bacteraemia: A 10-year regional population-based study of clinical and microbiological risk factors

    DEFF Research Database (Denmark)

    Jensen, U.S.; Knudsen, J.D.; Andersen, Christian Østergaard

    2010-01-01

    Background: A population-based nested case-control study was conducted in order to characterize patient factors and microbial species associated with recurrent bacteraemia. Methods: All patients with bacteraemia in a Danish region during 1996-2006 were investigated. Recurrence was defined based o...

  18. Controlling Japanese barberry: Alternative methods and impact on tick populations

    Science.gov (United States)

    Jeffrey S. Ward; Scott C. Williams; Thomas E. Worthley

    2011-01-01

    Japanese barberry (Berberis thunbergii) is classified as invasive in 20 states and four Canadian provinces. It is also established in another 11 states. In addition to forming dense thickets that can inhibit forest regeneration and native herbaceous plant populations, barberry understories can harbor greatly enhanced levels of blacklegged ticks (

  19. Population and antenatal-based HIV prevalence estimates in a high contracepting female population in rural South Africa

    Directory of Open Access Journals (Sweden)

    Barnighausen Till

    2007-07-01

    Full Text Available Abstract Background To present and compare population-based and antenatal-care (ANC sentinel surveillance HIV prevalence estimates among women in a rural South African population where both provision of ANC services and family planning is prevalent and fertility is declining. With a need, in such settings, to understand how to appropriately adjust ANC sentinel surveillance estimates to represent HIV prevalence in general populations, and with evidence of possible biases inherent to both surveillance systems, we explore differences between the two systems. There is particular emphasis on unrepresentative selection of ANC clinics and unrepresentative testing in the population. Methods HIV sero-prevalence amongst blood samples collected from women consenting to test during the 2005 annual longitudinal population-based serological survey was compared to anonymous unlinked HIV sero-prevalence amongst women attending antenatal care (ANC first visits in six clinics (January to May 2005. Both surveillance systems were conducted as part of the Africa Centre Demographic Information System. Results Population-based HIV prevalence estimates for all women (25.2% and pregnant women (23.7% were significantly lower than that for ANC attendees (37.7%. A large proportion of women attending urban or peri-urban clinics would be predicted to be resident within rural areas. Although overall estimates remained significantly different, presenting and standardising estimates by age and location (clinic for ANC-based estimates and individual-residence for population-based estimates made some group-specific estimates from the two surveillance systems more predictive of one another. Conclusion It is likely that where ANC coverage and contraceptive use is widespread and fertility is low, population-based surveillance under-estimates HIV prevalence due to unrepresentative testing by age, residence and also probably by HIV status, and that ANC sentinel surveillance over

  20. Probability Sampling Method for a Hidden Population Using Respondent-Driven Sampling: Simulation for Cancer Survivors.

    Science.gov (United States)

    Jung, Minsoo

    2015-01-01

    When there is no sampling frame within a certain group or the group is concerned that making its population public would bring social stigma, we say the population is hidden. It is difficult to approach this kind of population survey-methodologically because the response rate is low and its members are not quite honest with their responses when probability sampling is used. The only alternative known to address the problems caused by previous methods such as snowball sampling is respondent-driven sampling (RDS), which was developed by Heckathorn and his colleagues. RDS is based on a Markov chain, and uses the social network information of the respondent. This characteristic allows for probability sampling when we survey a hidden population. We verified through computer simulation whether RDS can be used on a hidden population of cancer survivors. According to the simulation results of this thesis, the chain-referral sampling of RDS tends to minimize as the sample gets bigger, and it becomes stabilized as the wave progresses. Therefore, it shows that the final sample information can be completely independent from the initial seeds if a certain level of sample size is secured even if the initial seeds were selected through convenient sampling. Thus, RDS can be considered as an alternative which can improve upon both key informant sampling and ethnographic surveys, and it needs to be utilized for various cases domestically as well.

  1. Calcium intake by adolescents: a population-based health survey

    Directory of Open Access Journals (Sweden)

    Daniela de Assumpção

    2016-06-01

    Full Text Available Abstract Objective To analyze calcium intake in adolescents according to sociodemographic variables, health-related behaviors, morbidities, and body mass index. Methods This was a cross-sectional population-based study, with a two-stage cluster sampling that used data from a survey conducted in Campinas, São Paulo, Brazil, between 2008 and 2009. Food intake was assessed using a 24-hour dietary recall. The study included 913 adolescents aged 10-19 years. Results Average nutrient intake was significantly lower in the segment with lower education of the head of the family and lower per capita family income, in individuals from other cities or states, those who consumed fruit less than four times a week, those who did not drink milk daily, those who were smokers, and those who reported the occurrence of headaches and dizziness. Higher mean calcium intake was found in individuals that slept less than seven hours a day. The prevalence of calcium intake below the recommendation was 88.6% (95% CI: 85.4-91.2. Conclusion The results alert to an insufficient calcium intake and suggest that certain subgroups of adolescents need specific strategies to increase the intake of this nutrient.

  2. Incidence of symptomatic osteochondritis dissecans lesions of the knee : A population-based study in Olmsted County

    NARCIS (Netherlands)

    Pareek, A.; Sanders, T. L.; Wu, I. T.; Larson, D. R.; Saris, D. B.F.; Krych, A.J.

    2017-01-01

    Objective: To (1) define population-based incidence of knee Osteochondritis dissecans (OCD) lesions using the population of Olmsted County, (2) examine trends over time, and (3) evaluate rate of surgical management over time. Method: Study population included 302 individuals who were diagnosed with

  3. Population-based prevention of influenza in Dutch general practice

    NARCIS (Netherlands)

    Hak, E; Hermens, R P; van Essen, G A; Kuyvenhoven, M M; de Melker, R A

    BACKGROUND: Although the effectiveness of influenza vaccination in high-risk groups has been proven, vaccine coverage continues to be less than 50% in The Netherlands. To improve vaccination rates, data on the organizational factors, which should be targeted in population-based prevention of

  4. Individual based model of slug population and spatial dynamics

    NARCIS (Netherlands)

    Choi, Y.H.; Bohan, D.A.; Potting, R.P.J.; Semenov, M.A.; Glen, D.M.

    2006-01-01

    The slug, Deroceras reticulatum, is one of the most important pests of agricultural and horticultural crops in UK and Europe. In this paper, a spatially explicit individual based model (IbM) is developed to study the dynamics of a population of D. reticulatum. The IbM establishes a virtual field

  5. Hepatoblastoma incidence in Taiwan: A population-based study

    Directory of Open Access Journals (Sweden)

    Giun-Yi Hung

    2018-06-01

    Full Text Available Background: The incidence of hepatoblastoma is not well known in Taiwan. The goal of this study was to investigate the incidence rates of hepatoblastoma by age and sex. Methods: The data of patients with hepatoblastoma diagnosed from 1995 to 2012 were obtained from the population-based Taiwan Cancer Registry. Incidence rates of hepatoblastoma according to sex and age were analyzed. This study employed the published methods of International Agency for Research on Cancer to calculate the age-standardized incidence rates (ASIRs, standard errors, 95% confidence intervals (CIs, and standardized incidence rate ratios (SIRRs. Results: In total, 211 patients were diagnosed with hepatoblastoma during the 18-year study period. The ASIR was 0.76 per million person-years. Hepatoblastoma was predominantly diagnosed in children (n = 184, 87.2%. By contrast, adolescents/adults (n = 10, 4.7% and elderly people (n = 17, 8.1% were rarely affected. The incidence peaked at ages 0–4 years with corresponding ASIR of 7.3 per million person-years. A significant male predilection was only found in children and elderly people, with male-to-female SIRRs of 1.23 and 1.89, respectively. During 1995–2012, the overall incidence of hepatoblastoma significantly increased only in children (annual percent change: 7.4%, 95% CI 3.9%–11.1%, p < 0.05 and specifically in boys (annual percent change: 6.5%, 95% CI 1.9%–11.2%, p < 0.05. Conclusion: Only 27 patients aged ≥ 15 years with hepatoblastoma were identified in this study, the existence of adult hepatoblastoma still requires novel molecular tools to elucidate. The association between the upward trend of hepatoblastoma incidence in boys and increased survival of prematurity in Taiwan warrants further investigations. Keywords: Hepatoblastoma, Incidence, Taiwan

  6. Neighborhood deprivation is strongly associated with participation in a population-based health check

    DEFF Research Database (Denmark)

    Bender, Anne Mette; Kawachi, Ichiro; Jørgensen, Torben

    2015-01-01

    BACKGROUND: We sought to examine whether neighborhood deprivation is associated with participation in a large population-based health check. Such analyses will help answer the question whether health checks, which are designed to meet the needs of residents in deprived neighborhoods, may increase...... participation and prove to be more effective in preventing disease. In Europe, no study has previously looked at the association between neighborhood deprivation and participation in a population-based health check. METHODS: The study population comprised 12,768 persons invited for a health check including...... screening for ischemic heart disease and lifestyle counseling. The study population was randomly drawn from a population of 179,097 persons living in 73 neighborhoods in Denmark. Data on neighborhood deprivation (percentage with basic education, with low income and not in work) and individual socioeconomic...

  7. Gaussian process-based Bayesian nonparametric inference of population size trajectories from gene genealogies.

    Science.gov (United States)

    Palacios, Julia A; Minin, Vladimir N

    2013-03-01

    Changes in population size influence genetic diversity of the population and, as a result, leave a signature of these changes in individual genomes in the population. We are interested in the inverse problem of reconstructing past population dynamics from genomic data. We start with a standard framework based on the coalescent, a stochastic process that generates genealogies connecting randomly sampled individuals from the population of interest. These genealogies serve as a glue between the population demographic history and genomic sequences. It turns out that only the times of genealogical lineage coalescences contain information about population size dynamics. Viewing these coalescent times as a point process, estimating population size trajectories is equivalent to estimating a conditional intensity of this point process. Therefore, our inverse problem is similar to estimating an inhomogeneous Poisson process intensity function. We demonstrate how recent advances in Gaussian process-based nonparametric inference for Poisson processes can be extended to Bayesian nonparametric estimation of population size dynamics under the coalescent. We compare our Gaussian process (GP) approach to one of the state-of-the-art Gaussian Markov random field (GMRF) methods for estimating population trajectories. Using simulated data, we demonstrate that our method has better accuracy and precision. Next, we analyze two genealogies reconstructed from real sequences of hepatitis C and human Influenza A viruses. In both cases, we recover more believed aspects of the viral demographic histories than the GMRF approach. We also find that our GP method produces more reasonable uncertainty estimates than the GMRF method. Copyright © 2013, The International Biometric Society.

  8. GIS-Based Population Model Applied to Nevada Transportation Routes

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.

    1999-01-01

    Recently, a model based on geographic information system (GIS) processing of US Census Block data has made high-resolution population analysis for transportation risk analysis technically and economically feasible. Population density bordering each kilometer of a route may be tabulated with specific route sections falling into each of three categories (Rural, Suburban or Urban) identified for separate risk analysis. In addition to the improvement in resolution of Urban areas along a route, the model provides a statistically-based correction to population densities in Rural and Suburban areas where Census Block dimensions may greatly exceed the 800-meter scale of interest. A semi-automated application of the GIS model to a subset of routes in Nevada (related to the Yucca Mountain project) are presented, and the results compared to previous models including a model based on published Census and other data. These comparisons demonstrate that meaningful improvement in accuracy and specificity of transportation risk analyses is dependent on correspondingly accurate and geographically-specific population density data

  9. Nose profile morphology and accuracy study of nose profile estimation method in Scottish subadult and Indonesian adult populations.

    Science.gov (United States)

    Sarilita, Erli; Rynn, Christopher; Mossey, Peter A; Black, Sue; Oscandar, Fahmi

    2018-05-01

    This study investigated nose profile morphology and its relationship to the skull in Scottish subadult and Indonesian adult populations, with the aim of improving the accuracy of forensic craniofacial reconstruction. Samples of 86 lateral head cephalograms from Dundee Dental School (mean age, 11.8 years) and 335 lateral head cephalograms from the Universitas Padjadjaran Dental Hospital, Bandung, Indonesia (mean age 24.2 years), were measured. The method of nose profile estimation based on skull morphology previously proposed by Rynn and colleagues in 2010 (FSMP 6:20-34) was tested in this study. Following this method, three nasal aperture-related craniometrics and six nose profile dimensions were measured from the cephalograms. To assess the accuracy of the method, six nose profile dimensions were estimated from the three craniometric parameters using the published method and then compared to the actual nose profile dimensions.In the Scottish subadult population, no sexual dimorphism was evident in the measured dimensions. In contrast, sexual dimorphism of the Indonesian adult population was evident in all craniometric and nose profile dimensions; notably, males exhibited statistically significant larger values than females. The published method by Rynn and colleagues (FSMP 6:20-34, 2010) performed better in the Scottish subadult population (mean difference of maximum, 2.35 mm) compared to the Indonesian adult population (mean difference of maximum, 5.42 mm in males and 4.89 mm in females).In addition, regression formulae were derived to estimate nose profile dimensions based on the craniometric measurements for the Indonesian adult population. The published method is not sufficiently accurate for use on the Indonesian population, so the derived method should be used. The accuracy of the published method by Rynn and colleagues (FSMP 6:20-34, 2010) was sufficiently reliable to be applied in Scottish subadult population.

  10. Population-based reference values for bone mineral density in young men

    DEFF Research Database (Denmark)

    Høiberg, M; Nielsen, Torben Leo; Wraae, K

    2007-01-01

    -energy X-ray absorptiometry (DXA) equipment. METHODS: The aim of the present study was 1) to establish population-based reference values for BMD in young men and 2) to study subgroups based on variables with suspected impact on bone metabolism. We included 783 young Caucasian men aged 20 to 30 years...... in the Odense Androgen Study (OAS). RESULTS: Peak BMD was attained within the third decade. Obesity (BMI > 30 kg/m2) was associated with higher BMD. Abuse of anabolic steroids as well as chronic illness was associated with lower BMD. Our population-based reference values for BMD of the total hip (1.078 +/- 0...

  11. Transgender Population Size in the United States: a Meta-Regression of Population-Based Probability Samples

    Science.gov (United States)

    Sevelius, Jae M.

    2017-01-01

    Background. Transgender individuals have a gender identity that differs from the sex they were assigned at birth. The population size of transgender individuals in the United States is not well-known, in part because official records, including the US Census, do not include data on gender identity. Population surveys today more often collect transgender-inclusive gender-identity data, and secular trends in culture and the media have created a somewhat more favorable environment for transgender people. Objectives. To estimate the current population size of transgender individuals in the United States and evaluate any trend over time. Search methods. In June and July 2016, we searched PubMed, Cumulative Index to Nursing and Allied Health Literature, and Web of Science for national surveys, as well as “gray” literature, through an Internet search. We limited the search to 2006 through 2016. Selection criteria. We selected population-based surveys that used probability sampling and included self-reported transgender-identity data. Data collection and analysis. We used random-effects meta-analysis to pool eligible surveys and used meta-regression to address our hypothesis that the transgender population size estimate would increase over time. We used subsample and leave-one-out analysis to assess for bias. Main results. Our meta-regression model, based on 12 surveys covering 2007 to 2015, explained 62.5% of model heterogeneity, with a significant effect for each unit increase in survey year (F = 17.122; df = 1,10; b = 0.026%; P = .002). Extrapolating these results to 2016 suggested a current US population size of 390 adults per 100 000, or almost 1 million adults nationally. This estimate may be more indicative for younger adults, who represented more than 50% of the respondents in our analysis. Authors’ conclusions. Future national surveys are likely to observe higher numbers of transgender people. The large variety in questions used to ask

  12. Quality is the key for emerging issues of population-based colonoscopy screening

    Directory of Open Access Journals (Sweden)

    Jin Young Yoon

    2018-01-01

    Full Text Available Colonoscopy is currently regarded as the gold standard and preferred method of screening for colorectal cancer (CRC. However, the benefit of colonoscopy screening may be blunted by low participation rates in population-based screening programs. Harmful effects of population-based colonoscopy screening may include complications induced by colonoscopy itself and by sedation, psychosocial distress, potential over-diagnosis, and socioeconomic burden. In addition, harmful effects of colonoscopy may increase with age and comorbidities. As the risk of adverse events in population-based colonoscopy screening may offset the benefit, the adverse events should be managed and monitored. To adopt population-based colonoscopy screening, consensus on the risks and benefits should be developed, focusing on potential harm, patient preference, socioeconomic considerations, and quality improvement of colonoscopy, as well as efficacy for CRC prevention. As suboptimal colonoscopy quality is a major pitfall of population-based screening, adequate training and regulation of screening colonoscopists should be the first step in minimizing variations in quality. Gastroenterologists should promote quality improvement, auditing, and training for colonoscopy in a population-based screening program.

  13. A nodal method based on the response-matrix method

    International Nuclear Information System (INIS)

    Cunha Menezes Filho, A. da; Rocamora Junior, F.D.

    1983-02-01

    A nodal approach based on the Response-Matrix method is presented with the purpose of investigating the possibility of mixing two different allocations in the same problem. It is found that the use of allocation of albedo combined with allocation of direct reflection produces good results for homogeneous fast reactor configurations. (Author) [pt

  14. Population size estimation of men who have sex with men through the network scale-up method in Japan.

    Directory of Open Access Journals (Sweden)

    Satoshi Ezoe

    Full Text Available BACKGROUND: Men who have sex with men (MSM are one of the groups most at risk for HIV infection in Japan. However, size estimates of MSM populations have not been conducted with sufficient frequency and rigor because of the difficulty, high cost and stigma associated with reaching such populations. This study examined an innovative and simple method for estimating the size of the MSM population in Japan. We combined an internet survey with the network scale-up method, a social network method for estimating the size of hard-to-reach populations, for the first time in Japan. METHODS AND FINDINGS: An internet survey was conducted among 1,500 internet users who registered with a nationwide internet-research agency. The survey participants were asked how many members of particular groups with known population sizes (firepersons, police officers, and military personnel they knew as acquaintances. The participants were also asked to identify the number of their acquaintances whom they understood to be MSM. Using these survey results with the network scale-up method, the personal network size and MSM population size were estimated. The personal network size was estimated to be 363.5 regardless of the sex of the acquaintances and 174.0 for only male acquaintances. The estimated MSM prevalence among the total male population in Japan was 0.0402% without adjustment, and 2.87% after adjusting for the transmission error of MSM. CONCLUSIONS: The estimated personal network size and MSM prevalence seen in this study were comparable to those from previous survey results based on the direct-estimation method. Estimating population sizes through combining an internet survey with the network scale-up method appeared to be an effective method from the perspectives of rapidity, simplicity, and low cost as compared with more-conventional methods.

  15. Stochastic weighted particle methods for population balance equations with coagulation, fragmentation and spatial inhomogeneity

    International Nuclear Information System (INIS)

    Lee, Kok Foong; Patterson, Robert I.A.; Wagner, Wolfgang; Kraft, Markus

    2015-01-01

    Graphical abstract: -- Highlights: •Problems concerning multi-compartment population balance equations are studied. •A class of fragmentation weight transfer functions is presented. •Three stochastic weighted algorithms are compared against the direct simulation algorithm. •The numerical errors of the stochastic solutions are assessed as a function of fragmentation rate. •The algorithms are applied to a multi-dimensional granulation model. -- Abstract: This paper introduces stochastic weighted particle algorithms for the solution of multi-compartment population balance equations. In particular, it presents a class of fragmentation weight transfer functions which are constructed such that the number of computational particles stays constant during fragmentation events. The weight transfer functions are constructed based on systems of weighted computational particles and each of it leads to a stochastic particle algorithm for the numerical treatment of population balance equations. Besides fragmentation, the algorithms also consider physical processes such as coagulation and the exchange of mass with the surroundings. The numerical properties of the algorithms are compared to the direct simulation algorithm and an existing method for the fragmentation of weighted particles. It is found that the new algorithms show better numerical performance over the two existing methods especially for systems with significant amount of large particles and high fragmentation rates.

  16. Comparative performance of different stochastic methods to simulate drug exposure and variability in a population.

    Science.gov (United States)

    Tam, Vincent H; Kabbara, Samer

    2006-10-01

    Monte Carlo simulations (MCSs) are increasingly being used to predict the pharmacokinetic variability of antimicrobials in a population. However, various MCS approaches may differ in the accuracy of the predictions. We compared the performance of 3 different MCS approaches using a data set with known parameter values and dispersion. Ten concentration-time profiles were randomly generated and used to determine the best-fit parameter estimates. Three MCS methods were subsequently used to simulate the AUC(0-infinity) of the population, using the central tendency and dispersion of the following in the subject sample: 1) K and V; 2) clearance and V; 3) AUC(0-infinity). In each scenario, 10000 subject simulations were performed. Compared to true AUC(0-infinity) of the population, mean biases by various methods were 1) 58.4, 2) 380.7, and 3) 12.5 mg h L(-1), respectively. Our results suggest that the most realistic MCS approach appeared to be based on the variability of AUC(0-infinity) in the subject sample.

  17. [Use of psychoactive substances and contraceptive methods by the Brazilian urban population, 2005].

    Science.gov (United States)

    Bastos, Francisco I; Cunha, Cynthia B; Bertoni, Neilane

    2008-06-01

    To analyze the relationship between utilization patterns for condoms and other contraceptive methods and the consumption of alcohol and drugs. Exploratory study based on data from a probabilistic sample of 5,040 interviewees aged 16 to 65 years living in large urban regions of Brazil in 2005. The data were collected by means of questionnaires. The chi-square automatic interaction classification tree technique was used to study the use of condoms among interviewees of both sexes and other contraceptive methods among women, at the time of the last vaginal sexual intercourse. Among young and middle-aged adults of both sexes and young men in stable relationships, condom use was less frequent among those who said they used psychoactive substances (alcohol and/or illegal drugs). The possible modulating effect of psychoactive substances on contraceptive practices among mature women seems to be more straightforward, compared to the more subtle effects observed among younger women, for whom the different social classes they belonged to seemed to play a more important role. Despite the limitations resulting from an exploratory study, the fact that this was a representative sample of the urban population of Brazil and not from vulnerable populations, reinforces the need to implement integrated public policies directed towards the general population, with regard to preventing drug consumption, alcohol abuse, sexually transmitted infections, HIV/AIDS and unwanted pregnancy and promoting sexual and reproductive health.

  18. Stochastic weighted particle methods for population balance equations with coagulation, fragmentation and spatial inhomogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kok Foong [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom); Patterson, Robert I.A.; Wagner, Wolfgang [Weierstrass Institute for Applied Analysis and Stochastics, Mohrenstraße 39, 10117 Berlin (Germany); Kraft, Markus, E-mail: mk306@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA (United Kingdom); School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459 (Singapore)

    2015-12-15

    Graphical abstract: -- Highlights: •Problems concerning multi-compartment population balance equations are studied. •A class of fragmentation weight transfer functions is presented. •Three stochastic weighted algorithms are compared against the direct simulation algorithm. •The numerical errors of the stochastic solutions are assessed as a function of fragmentation rate. •The algorithms are applied to a multi-dimensional granulation model. -- Abstract: This paper introduces stochastic weighted particle algorithms for the solution of multi-compartment population balance equations. In particular, it presents a class of fragmentation weight transfer functions which are constructed such that the number of computational particles stays constant during fragmentation events. The weight transfer functions are constructed based on systems of weighted computational particles and each of it leads to a stochastic particle algorithm for the numerical treatment of population balance equations. Besides fragmentation, the algorithms also consider physical processes such as coagulation and the exchange of mass with the surroundings. The numerical properties of the algorithms are compared to the direct simulation algorithm and an existing method for the fragmentation of weighted particles. It is found that the new algorithms show better numerical performance over the two existing methods especially for systems with significant amount of large particles and high fragmentation rates.

  19. Assessment of military population-based psychological resilience programs.

    Science.gov (United States)

    Morgan, Brenda J; Bibb, Sandra C Garmon

    2011-09-01

    Active duty service members' (ADSMs) seemingly poor adaptability to traumatic stressors is a risk to force health. Enhancing the psychological resilience of ADSMs has become a key focus of Department of Defense (DoD) leaders and the numbers of military programs for enhancing psychological resilience have increased. The purpose of this article is to describe the results of an assessment conducted to determine comprehensiveness of current psychological resilience building programs that target ADSMs. A modified six-step, population-based needs assessment was used to evaluate resilience programs designed to meet the psychological needs of the ADSM population. The assessment results revealed a gap in published literature regarding program outcomes. DoD leaders may benefit from targeted predictive research that assesses program effectiveness outcomes. The necessity of including preventive, evidence-based interventions in new programs, such as positive emotion interventions shown to enhance psychological resilience in civilian samples, is also recommended.

  20. Lack of Population Structure in Coriander Populations Based on SDS (Seed Storage Protein Page Analysis

    Directory of Open Access Journals (Sweden)

    Gülsüm Yaldiz

    2016-08-01

    Full Text Available Genetic variation is prerequisite for plant breeding. Nothing information existed in the literature for available diversity of Coriander accession in Turkey. Plant breeding activities are negligible in Turkey. So in order to start effective plant breeding program in Turkey, information on the available genetic diversity is viable. Therefore we planned to study the genetic variation and population structure of 29 Coriander accessions by seed storage protein (SDS. SDS analysis elaborated the lack of population structure and genetic bottleneck in the Coriander accessions in Turkey. Based on the results of this study, it was clear that sampling strategy was not appropriate and plant introduction should be made from different sources and diverse genotypes should be used as parents to initialize the effective Turkish Coriander breeding program.

  1. Genetic diversity of Iranian honey bee (Apis mellifera meda Skorikow, 1829) populations based on ISSR markers.

    Science.gov (United States)

    Rahimi, A; Mirmoayedi, A; Kahrizi, D; Zarei, L; Jamali, S

    2016-04-30

    Honey bee is one of the most important insects considering its role in agriculture,ecology and economy as a whole. In this study, the genetic diversity of different Iranian honey bee populations was evaluated using inter simple sequence repeat (ISSR) markers. During May to September 2014, 108 young worker honey bees were collected from six different populations in 30 different geoclimatic locations from Golestan, Mazendaran, Guilan, West Azerbaijan, East Azerbaijan, Ardebil provinces of Iran. DNA was extracted from the worker honey bees. The quality and quantity of extracted DNA were measured. A set of ten primers were screened with the laboratory populations of honey bees. The number of fragments produced in the different honey bee populations varied from 3 to 10, varying within 150 to 1500 bp. The used ten ISSR primers generated 40 polymorphic fragments, and the average heterozygosity for each primer was 0.266. Maximum numbers of bands were recorded for primer A1. A dendrogram based on the Unweighted Pair Group Method with Arithmetic mean (UPGMA) method generated two sub-clusters. Honey bee populations of Golestan, Mazendaran, Guilan provinces were located in the first group. The second group included honey bee populations of Ardebil, West Azerbaijan, East Azerbaijan provinces, but this group showed a close relationship with other populations. The results showed obviously the ability of the ISSR marker technique to detect the genetic diversity among the honey bee populations.

  2. Population Estimation in Singapore Based on Remote Sensing and Open Data

    Science.gov (United States)

    Guo, H.; Cao, K.; Wang, P.

    2017-09-01

    Population estimation statistics are widely used in government, commercial and educational sectors for a variety of purposes. With growing emphases on real-time and detailed population information, data users nowadays have switched from traditional census data to more technology-based data source such as LiDAR point cloud and High-Resolution Satellite Imagery. Nevertheless, such data are costly and periodically unavailable. In this paper, the authors use West Coast District, Singapore as a case study to investigate the applicability and effectiveness of using satellite image from Google Earth for extraction of building footprint and population estimation. At the same time, volunteered geographic information (VGI) is also utilized as ancillary data for building footprint extraction. Open data such as Open Street Map OSM could be employed to enhance the extraction process. In view of challenges in building shadow extraction, this paper discusses several methods including buffer, mask and shape index to improve accuracy. It also illustrates population estimation methods based on building height and number of floor estimates. The results show that the accuracy level of housing unit method on population estimation can reach 92.5 %, which is remarkably accurate. This paper thus provides insights into techniques for building extraction and fine-scale population estimation, which will benefit users such as urban planners in terms of policymaking and urban planning of Singapore.

  3. POPULATION ESTIMATION IN SINGAPORE BASED ON REMOTE SENSING AND OPEN DATA

    Directory of Open Access Journals (Sweden)

    H. Guo

    2017-09-01

    Full Text Available Population estimation statistics are widely used in government, commercial and educational sectors for a variety of purposes. With growing emphases on real-time and detailed population information, data users nowadays have switched from traditional census data to more technology-based data source such as LiDAR point cloud and High-Resolution Satellite Imagery. Nevertheless, such data are costly and periodically unavailable. In this paper, the authors use West Coast District, Singapore as a case study to investigate the applicability and effectiveness of using satellite image from Google Earth for extraction of building footprint and population estimation. At the same time, volunteered geographic information (VGI is also utilized as ancillary data for building footprint extraction. Open data such as Open Street Map(OSM)could be employed to enhance the extraction process. In view of challenges in building shadow extraction, this paper discusses several methods including buffer, mask and shape index to improve accuracy. It also illustrates population estimation methods based on building height and number of floor estimates. The results show that the accuracy level of housing unit method on population estimation can reach 92.5 %, which is remarkably accurate. This paper thus provides insights into techniques for building extraction and fine-scale population estimation, which will benefit users such as urban planners in terms of policymaking and urban planning of Singapore.

  4. Reference man models based on normal data from human populations

    International Nuclear Information System (INIS)

    Tanaka, Gi-ichiro; Kawamura, Hisao

    2000-01-01

    Quantitative description of the physical, and metabolic parameters of the human body is the very basic for internal dosimetry. Compilation of anatomical and other types of data Asian populations for internal (and external) dosimetry is of grate significance because of the potential spread of nuclear energy use in the Asian region and the major contribution of the region to the world population (about 58%). It has been observed that some differences exist for habitat, race, body sizes and pattern of food consumption. In the early stage of revision of ICRP Reference man by the Task Group, Characteristics of the human body of non-European populations received considerable attention as well as those of the European populations of different sexes and ages. In this context, an IAEA-RCA Co-ordinated Research Program on Compilation of Anatomical, Physiological and Metabolic Characteristics for a Reference Asian Man endorsed. In later stages of reference Man revision, anatomical data for Asians was discusses together with those of European populations, presumably due to ICRP's decision of unanimous use of the Reference Man for radiation protection. Reference man models for adults and 15, 10, 5, 1, 0 year-old males and females of Asian populations were developed for use in internal and external dosimetry. Based on the concept of ICRP Reference Man (Publication 23), the reference values were derived from the normal organ mass data for Japanese and statistical data on the physique and nutrition of Japanese and Chinese. Also incorporated were variations in physical measurements, as observed in the above mentioned IAEA-RCA Co-ordinated Research Program. The work was partly carried out within the activities of the ICRP Task Group on Reference Man. The weight of the skeleton was adjusted following the revised values in Publication 70. This paper will report basic shared and non-shared characteristics of Reference Man' for Asians and ICRP Reference Man. (author)

  5. A UK population-based study of the relationship between mental disorder and victimisation

    NARCIS (Netherlands)

    Hart, C.; Vet, R. de; Moran, P.; Hatch, S.L.; Dean, K.

    2012-01-01

    PURPOSE: To establish the prevalence of victimisation in a UK population-based sample and to investigate the association between mental disorder and victimisation in both cross-sectional and prospective manner, whilst adjusting for potential confounds. METHODS: Data from the National Child

  6. Epidemiology of multiple congenital anomalies in Europe: A EUROCAT population-based registry study

    DEFF Research Database (Denmark)

    Calzolari, Elisa; Barisic, Ingeborg; Loane, Maria

    2014-01-01

    BACKGROUND: This study describes the prevalence, associated anomalies, and demographic characteristics of cases of multiple congenital anomalies (MCA) in 19 population-based European registries (EUROCAT) covering 959,446 births in 2004 and 2010. METHODS: EUROCAT implemented a computer algorithm f...

  7. A review of population-based studies on hypertension in Ghana ...

    African Journals Online (AJOL)

    Background: Hypertension is becoming a common health problem worldwide with increasing life expectancy and increasing prevalence of risk factors. Epidemiological data on hypertension in Ghana is necessary to guide policy and develop effective interventions. Methods: A review of population-based studies on ...

  8. Pneumococcal serotypes and mortality following invasive pneumococcal disease: a population-based cohort study

    DEFF Research Database (Denmark)

    Harboe, Zitta B; Thomsen, Reimar W; Riis, Anders

    2009-01-01

    BACKGROUND: Pneumococcal disease is a leading cause of morbidity and mortality worldwide. The aim of this study was to investigate the association between specific pneumococcal serotypes and mortality from invasive pneumococcal disease (IPD). METHODS AND FINDINGS: In a nationwide population-based...

  9. Color image definition evaluation method based on deep learning method

    Science.gov (United States)

    Liu, Di; Li, YingChun

    2018-01-01

    In order to evaluate different blurring levels of color image and improve the method of image definition evaluation, this paper proposed a method based on the depth learning framework and BP neural network classification model, and presents a non-reference color image clarity evaluation method. Firstly, using VGG16 net as the feature extractor to extract 4,096 dimensions features of the images, then the extracted features and labeled images are employed in BP neural network to train. And finally achieve the color image definition evaluation. The method in this paper are experimented by using images from the CSIQ database. The images are blurred at different levels. There are 4,000 images after the processing. Dividing the 4,000 images into three categories, each category represents a blur level. 300 out of 400 high-dimensional features are trained in VGG16 net and BP neural network, and the rest of 100 samples are tested. The experimental results show that the method can take full advantage of the learning and characterization capability of deep learning. Referring to the current shortcomings of the major existing image clarity evaluation methods, which manually design and extract features. The method in this paper can extract the images features automatically, and has got excellent image quality classification accuracy for the test data set. The accuracy rate is 96%. Moreover, the predicted quality levels of original color images are similar to the perception of the human visual system.

  10. A population-based study of glioblastoma multiforme

    International Nuclear Information System (INIS)

    Paszat, Lawrence; Laperriere, Normand; Groome, Patti; Schulze, Karleen; Mackillop, William; Holowaty, Eric

    2001-01-01

    Purpose: To describe (1) the use of surgery and radiotherapy (RT) in the treatment of patients with glioblastoma (GBM) in Ontario, (2) survival, and (3) proportion of survival time spent in the hospital after diagnosis. Methods and Materials: We performed a population-based cohort study of all Ontario Cancer Registry (OCR) cases of GBM diagnosed between 1982 and 1994. We linked OCR records, hospital files containing surgical procedure codes from the Canadian Institute for Health Information, and province-wide RT records. We studied the odds of treatment using multivariate logistic regression. We expressed the time spent in the hospital as the mean number of days per case, and as a proportion of the interval between diagnosis and death, or 24 months following diagnosis, whichever came first. We used the life-table method and Cox proportional hazards regression to describe survival. Results: The proportion of patients with GBM undergoing any surgery directed at the tumor varied with age (p<0.0001) and region of residence (p<0.0001). The proportion undergoing RT varied with age (p<0.0001), region of residence (p<0.0001), and year of diagnosis (p=0.01). RT dose ≥53.5 Gy varied with age (p<0.0001), region of residence (p<0.0001), and year of diagnosis (p=0.0002). Median survival was 11 months among patients receiving RT and 3 months among those not receiving RT. The percentage of survival time spent in the hospital was similar among those who received from 49.5 to <53.5 Gy, compared to ≥53.5 Gy. Overall survival and the adjusted relative risk of death varied with age and region of residence. Conclusion: We observed practice variation in the treatment of patients with GBM according to age, region of residence, and year of diagnosis. Survival did not increase during the study period. The variation in RT dose between those receiving from 49.5 to <53.5 Gy compared to ≥53.5 Gy was not paralleled by variation in survival between regions where one or the other of the

  11. History based batch method preserving tally means

    International Nuclear Information System (INIS)

    Shim, Hyung Jin; Choi, Sung Hoon

    2012-01-01

    In the Monte Carlo (MC) eigenvalue calculations, the sample variance of a tally mean calculated from its cycle-wise estimates is biased because of the inter-cycle correlations of the fission source distribution (FSD). Recently, we proposed a new real variance estimation method named the history-based batch method in which a MC run is treated as multiple runs with small number of histories per cycle to generate independent tally estimates. In this paper, the history-based batch method based on the weight correction is presented to preserve the tally mean from the original MC run. The effectiveness of the new method is examined for the weakly coupled fissile array problem as a function of the dominance ratio and the batch size, in comparison with other schemes available

  12. Model-Based Method for Sensor Validation

    Science.gov (United States)

    Vatan, Farrokh

    2012-01-01

    Fault detection, diagnosis, and prognosis are essential tasks in the operation of autonomous spacecraft, instruments, and in situ platforms. One of NASA s key mission requirements is robust state estimation. Sensing, using a wide range of sensors and sensor fusion approaches, plays a central role in robust state estimation, and there is a need to diagnose sensor failure as well as component failure. Sensor validation can be considered to be part of the larger effort of improving reliability and safety. The standard methods for solving the sensor validation problem are based on probabilistic analysis of the system, from which the method based on Bayesian networks is most popular. Therefore, these methods can only predict the most probable faulty sensors, which are subject to the initial probabilities defined for the failures. The method developed in this work is based on a model-based approach and provides the faulty sensors (if any), which can be logically inferred from the model of the system and the sensor readings (observations). The method is also more suitable for the systems when it is hard, or even impossible, to find the probability functions of the system. The method starts by a new mathematical description of the problem and develops a very efficient and systematic algorithm for its solution. The method builds on the concepts of analytical redundant relations (ARRs).

  13. Modelling population distribution using remote sensing imagery and location-based data

    Science.gov (United States)

    Song, J.; Prishchepov, A. V.

    2017-12-01

    Detailed spatial distribution of population density is essential for city studies such as urban planning, environmental pollution and city emergency, even estimate pressure on the environment and human exposure and risks to health. However, most of the researches used census data as the detailed dynamic population distribution are difficult to acquire, especially in microscale research. This research describes a method using remote sensing imagery and location-based data to model population distribution at the function zone level. Firstly, urban functional zones within a city were mapped by high-resolution remote sensing images and POIs. The workflow of functional zones extraction includes five parts: (1) Urban land use classification. (2) Segmenting images in built-up area. (3) Identification of functional segments by POIs. (4) Identification of functional blocks by functional segmentation and weight coefficients. (5) Assessing accuracy by validation points. The result showed as Fig.1. Secondly, we applied ordinary least square and geographically weighted regression to assess spatial nonstationary relationship between light digital number (DN) and population density of sampling points. The two methods were employed to predict the population distribution over the research area. The R²of GWR model were in the order of 0.7 and typically showed significant variations over the region than traditional OLS model. The result showed as Fig.2.Validation with sampling points of population density demonstrated that the result predicted by the GWR model correlated well with light value. The result showed as Fig.3. Results showed: (1) Population density is not linear correlated with light brightness using global model. (2) VIIRS night-time light data could estimate population density integrating functional zones at city level. (3) GWR is a robust model to map population distribution, the adjusted R2 of corresponding GWR models were higher than the optimal OLS models

  14. Wealth Inequality and Mental Disability Among the Chinese Population: A Population Based Study

    Science.gov (United States)

    Wang, Zhenjie; Du, Wei; Pang, Lihua; Zhang, Lei; Chen, Gong; Zheng, Xiaoying

    2015-01-01

    In the study described herein, we investigated and explored the association between wealth inequality and the risk of mental disability in the Chinese population. We used nationally represented, population-based data from the second China National Sample Survey on Disability, conducted in 2006. A total of 1,724,398 study subjects between the ages of 15 and 64, including 10,095 subjects with mental disability only, were used for the analysis. Wealth status was estimated by a wealth index that was derived from a principal component analysis of 10 household assets and four other variables related to wealth. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) for mental disability for each category, with the lowest quintile category as the referent. Confounding variables under consideration were age, gender, residence area, marital status, ethnicity, education, current employment status, household size, house type, homeownership and living arrangement. The distribution of various types and severities of mental disability differed significantly by wealth index category in the present population. Wealth index category had a positive association with mild mental disability (p for trend wealth index category had a significant, inverse association with mental disability when all severities of mental disability were taken into consideration. This study’s results suggest that wealth is a significant factor in the distribution of mental disability and it might have different influences on various types and severities of mental disability. PMID:26492258

  15. Wealth Inequality and Mental Disability Among the Chinese Population: A Population Based Study.

    Science.gov (United States)

    Wang, Zhenjie; Du, Wei; Pang, Lihua; Zhang, Lei; Chen, Gong; Zheng, Xiaoying

    2015-10-19

    In the study described herein, we investigated and explored the association between wealth inequality and the risk of mental disability in the Chinese population. We used nationally represented, population-based data from the second China National Sample Survey on Disability, conducted in 2006. A total of 1,724,398 study subjects between the ages of 15 and 64, including 10,095 subjects with mental disability only, were used for the analysis. Wealth status was estimated by a wealth index that was derived from a principal component analysis of 10 household assets and four other variables related to wealth. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) for mental disability for each category, with the lowest quintile category as the referent. Confounding variables under consideration were age, gender, residence area, marital status, ethnicity, education, current employment status, household size, house type, homeownership and living arrangement. The distribution of various types and severities of mental disability differed significantly by wealth index category in the present population. Wealth index category had a positive association with mild mental disability (p for trend disability (p for trend disability when all severities of mental disability were taken into consideration. This study's results suggest that wealth is a significant factor in the distribution of mental disability and it might have different influences on various types and severities of mental disability.

  16. Evolutionary game theory using agent-based methods.

    Science.gov (United States)

    Adami, Christoph; Schossau, Jory; Hintze, Arend

    2016-12-01

    Evolutionary game theory is a successful mathematical framework geared towards understanding the selective pressures that affect the evolution of the strategies of agents engaged in interactions with potential conflicts. While a mathematical treatment of the costs and benefits of decisions can predict the optimal strategy in simple settings, more realistic settings such as finite populations, non-vanishing mutations rates, stochastic decisions, communication between agents, and spatial interactions, require agent-based methods where each agent is modeled as an individual, carries its own genes that determine its decisions, and where the evolutionary outcome can only be ascertained by evolving the population of agents forward in time. While highlighting standard mathematical results, we compare those to agent-based methods that can go beyond the limitations of equations and simulate the complexity of heterogeneous populations and an ever-changing set of interactors. We conclude that agent-based methods can predict evolutionary outcomes where purely mathematical treatments cannot tread (for example in the weak selection-strong mutation limit), but that mathematics is crucial to validate the computational simulations. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Population-based strategies to control manufacturing epidemics.

    Science.gov (United States)

    Gorini, Giuseppe

    2017-01-01

    "The multinational corporations producing tobacco, alcohol, soft drinks, and processed foods have a role of vectors in the increase of chronic diseases, so that one can speak of manufacturing epidemics. The main aim of this paper is to conduct a literature review on different approaches in population-based interventions to stem the rise in consumption of unhealthy products. Different approaches were found: • command-and-control regulations: the route is definitely more advanced for tobacco with the implementation of an international treaty, which requires 180 ratifying states to implement a series of tobacco control policies. Similar regulations have been partially adopted to reduce alcohol use and to increase taxes of sugar-sweetened beverages; • multinational corporations in few Countries can voluntarily adopt recommendations on media campaigns and on labelling of soft drinks and processed foods; • in order to reduce salt in foods, many Countries developed voluntary agreements with industries with monitoring systems to assess compliance. Population-based interventions to try to align the interests of multinational corporations with those of public health are described in literature: • the "Health Footprint" programme; • the performance-based regulation which could oblige industry to take responsibility to reduce the harmful consequences of the use of their unhealthy commodities; • the price-cap regulation, usually applied to the utilities sector, would set a cap on the price of the tobacco industry, raising the tobacco taxes by 500 million euros per year. In order to reduce the burden of chronic disease, one of the objectives of the Italian National Prevention Plan, a working group including non-governmental organizations and experts in communication, social marketing, and lifestyles should be organized by the Ministry of Health in order to identify which population-based interventions could be implemented in Italy in next years to stem the rise of

  18. Spectrum estimation method based on marginal spectrum

    International Nuclear Information System (INIS)

    Cai Jianhua; Hu Weiwen; Wang Xianchun

    2011-01-01

    FFT method can not meet the basic requirements of power spectrum for non-stationary signal and short signal. A new spectrum estimation method based on marginal spectrum from Hilbert-Huang transform (HHT) was proposed. The procession of obtaining marginal spectrum in HHT method was given and the linear property of marginal spectrum was demonstrated. Compared with the FFT method, the physical meaning and the frequency resolution of marginal spectrum were further analyzed. Then the Hilbert spectrum estimation algorithm was discussed in detail, and the simulation results were given at last. The theory and simulation shows that under the condition of short data signal and non-stationary signal, the frequency resolution and estimation precision of HHT method is better than that of FFT method. (authors)

  19. Accurate and fast methods to estimate the population mutation rate from error prone sequences

    Directory of Open Access Journals (Sweden)

    Miyamoto Michael M

    2009-08-01

    Full Text Available Abstract Background The population mutation rate (θ remains one of the most fundamental parameters in genetics, ecology, and evolutionary biology. However, its accurate estimation can be seriously compromised when working with error prone data such as expressed sequence tags, low coverage draft sequences, and other such unfinished products. This study is premised on the simple idea that a random sequence error due to a chance accident during data collection or recording will be distributed within a population dataset as a singleton (i.e., as a polymorphic site where one sampled sequence exhibits a unique base relative to the common nucleotide of the others. Thus, one can avoid these random errors by ignoring the singletons within a dataset. Results This strategy is implemented under an infinite sites model that focuses on only the internal branches of the sample genealogy where a shared polymorphism can arise (i.e., a variable site where each alternative base is represented by at least two sequences. This approach is first used to derive independently the same new Watterson and Tajima estimators of θ, as recently reported by Achaz 1 for error prone sequences. It is then used to modify the recent, full, maximum-likelihood model of Knudsen and Miyamoto 2, which incorporates various factors for experimental error and design with those for coalescence and mutation. These new methods are all accurate and fast according to evolutionary simulations and analyses of a real complex population dataset for the California seahare. Conclusion In light of these results, we recommend the use of these three new methods for the determination of θ from error prone sequences. In particular, we advocate the new maximum likelihood model as a starting point for the further development of more complex coalescent/mutation models that also account for experimental error and design.

  20. Residual Motion and Duty Time in Respiratory Gating Radiotherapy Using Individualized or Population-Based Windows

    International Nuclear Information System (INIS)

    Fuji, Hiroshi; Asada, Yoshihiro; Numano, Masumi; Yamashita, Haruo; Nishimura, Tetsuo; Hashimoto, Takayuki; Harada, Hideyuki; Asakura, Hirofumi; Murayama, Shigeyuki

    2009-01-01

    Purpose: The efficiency and precision of respiratory gated radiation therapy for tumors is affected by variations in respiration-induced tumor motion. We evaluated the use of individualized and population-based parameters for such treatment. Methods and Materials: External respiratory signal records and images of respiration-induced tumor motion were obtained from 42 patients undergoing respiratory gated radiation therapy for liver tumors. Gating window widths were calculated for each patient, with 2, 4, and 10 mm of residual motion, and the mean was defined as the population-based window width. Residual motions based on population-based and predefined window widths were compared. Duty times based on whole treatment sessions, at various window levels, were calculated. The window level giving the longest duty time was defined as the individualized most efficient level (MEL). MELs were also calculated based on the first 10 breathing cycles. The duty times for population-based MELs (defined as mean MELs) and individualized MELs were compared. Results: Tracks of respiration-induced tumor motion ranged from 3 to 50 mm. Half of the patients had larger actual residual motions than the assigned residual motions. Duty times were greater when based on individualized, rather than population-based, window widths. The MELs established during whole treatment sessions for 2 mm and 4 mm of residual motion gave significantly increased duty times, whereas those calculated using the first 10 breathing cycles showed only marginal increases. Conclusions: Using individualized window widths and levels provided more precise and efficient respiratory gated radiation therapy. However, methods for predicting individualized window levels before treatment remain to be explored.

  1. Interchange Recognition Method Based on CNN

    Directory of Open Access Journals (Sweden)

    HE Haiwei

    2018-03-01

    Full Text Available The identification and classification of interchange structures in OSM data can provide important information for the construction of multi-scale model, navigation and location services, congestion analysis, etc. The traditional method of interchange identification relies on the low-level characteristics of artificial design, and cannot distinguish the complex interchange structure with interference section effectively. In this paper, a new method based on convolutional neural network for identification of the interchange is proposed. The method combines vector data with raster image, and uses neural network to learn the fuzzy characteristics of the interchange, and classifies the complex interchange structure in OSM. Experiments show that this method has strong anti-interference, and has achieved good results in the classification of complex interchange shape, and there is room for further improvement with the expansion of the case base and the optimization of neural network model.

  2. Cyberbullying among Finnish adolescents – a population-based study

    Directory of Open Access Journals (Sweden)

    Lindfors Pirjo L

    2012-11-01

    Full Text Available Abstract Background Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Methods Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey. The respondents could answer via the internet or paper questionnaire. Results The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%; and being a victim was slightly more common than being a bully (11% vs. 9%. Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Conclusions Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying

  3. Cyberbullying among Finnish adolescents – a population-based study

    Science.gov (United States)

    2012-01-01

    Background Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Methods Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey). The respondents could answer via the internet or paper questionnaire. Results The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%); and being a victim was slightly more common than being a bully (11% vs. 9%). Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Conclusions Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying exposure differed between

  4. Automation of GIS-Based Population Data-Collection for Transportation Risk Analysis

    International Nuclear Information System (INIS)

    MILLS, G. SCOTT; NEUHAUSER, SIEGLINDE

    1999-01-01

    Estimation of the potential radiological risks associated with highway transport of radioactive materials (RAM) requires input data describing population densities adjacent to all portions of the route to be traveled. Previously, aggregated risks for entire multi-state routes were adequately estimated from population data with low geographic resolution. Current demands for geographically-specific risk estimates require similar increases in resolution of population density adjacent to route segments. With the advent of commercial geographic information systems (GISs) and databases describing highways, U.S. Census Blocks, and other information that is geographically distributed, it became feasible to determine and tabulate population characteristics along transportation routes with 1-kilometer resolution. This report describes an automated method of collecting population data adjacent to route segments (for calculation of incident-free doses) based on a commercial GIS. It also describes a statistical method of resolving remaining resolution issues, and an adaptation of the automation method to collection of data on population under a hypothetical plume of contamination resulting from a potential transportation accident

  5. Recommendation advertising method based on behavior retargeting

    Science.gov (United States)

    Zhao, Yao; YIN, Xin-Chun; CHEN, Zhi-Min

    2011-10-01

    Online advertising has become an important business in e-commerce. Ad recommended algorithms are the most critical part in recommendation systems. We propose a recommendation advertising method based on behavior retargeting which can avoid leakage click of advertising due to objective reasons and can observe the changes of the user's interest in time. Experiments show that our new method can have a significant effect and can be further to apply to online system.

  6. Personnel Selection Based on Fuzzy Methods

    Directory of Open Access Journals (Sweden)

    Lourdes Cañós

    2011-03-01

    Full Text Available The decisions of managers regarding the selection of staff strongly determine the success of the company. A correct choice of employees is a source of competitive advantage. We propose a fuzzy method for staff selection, based on competence management and the comparison with the valuation that the company considers the best in each competence (ideal candidate. Our method is based on the Hamming distance and a Matching Level Index. The algorithms, implemented in the software StaffDesigner, allow us to rank the candidates, even when the competences of the ideal candidate have been evaluated only in part. Our approach is applied in a numerical example.

  7. Comparison between ARIMA and DES Methods of Forecasting Population for Housing Demand in Johor

    OpenAIRE

    Alias Ahmad Rizal; Zainun Noor Yasmin; Abdul Rahman Ismail

    2016-01-01

    Forecasting accuracy is a primary criterion in selecting appropriate method of prediction. Even though there are various methods of forecasting however not all of these methods are able to predict with good accuracy. This paper presents an evaluation of two methods of population forecasting for housing demand. These methods are Autoregressive Integrated Moving Average (ARIMA) and Double Exponential Smoothing (DES). Both of the methods are principally adopting univariate time series analysis w...

  8. Detecting population recovery using gametic disequilibrium-based effective population size estimates

    Science.gov (United States)

    David A. Tallmon; Robin S. Waples; Dave Gregovich; Michael K. Schwartz

    2012-01-01

    Recovering populations often must meet specific growth rate or abundance targets before their legal status can be changed from endangered or threatened. While the efficacy, power, and performance of population metrics to infer trends in declining populations has received considerable attention, how these same metrics perform when populations are increasing is less...

  9. A spray based method for biofilm removal

    NARCIS (Netherlands)

    Cense, A.W.

    2005-01-01

    Biofilm growth on human teeth is the cause of oral diseases such as caries (tooth decay), gingivitis (inflammation of the gums) and periodontitis (inflammation of the tooth bone). In this thesis, a water based cleaning method is designed for removal of oral biofilms, or dental plaque. The first part

  10. Arts-Based Methods in Education

    DEFF Research Database (Denmark)

    Chemi, Tatiana; Du, Xiangyun

    2017-01-01

    This chapter introduces the field of arts-based methods in education with a general theoretical perspective, reviewing the journey of learning in connection to the arts, and the contribution of the arts to societies from an educational perspective. Also presented is the rationale and structure...

  11. Application of the backstepping method to the prediction of increase or decrease of infected population.

    Science.gov (United States)

    Kuniya, Toshikazu; Sano, Hideki

    2016-05-10

    In mathematical epidemiology, age-structured epidemic models have usually been formulated as the boundary-value problems of the partial differential equations. On the other hand, in engineering, the backstepping method has recently been developed and widely studied by many authors. Using the backstepping method, we obtained a boundary feedback control which plays the role of the threshold criteria for the prediction of increase or decrease of newly infected population. Under an assumption that the period of infectiousness is same for all infected individuals (that is, the recovery rate is given by the Dirac delta function multiplied by a sufficiently large positive constant), the prediction method is simplified to the comparison of the numbers of reported cases at the current and previous time steps. Our prediction method was applied to the reported cases per sentinel of influenza in Japan from 2006 to 2015 and its accuracy was 0.81 (404 correct predictions to the total 500 predictions). It was higher than that of the ARIMA models with different orders of the autoregressive part, differencing and moving-average process. In addition, a proposed method for the estimation of the number of reported cases, which is consistent with our prediction method, was better than that of the best-fitted ARIMA model ARIMA(1,1,0) in the sense of mean square error. Our prediction method based on the backstepping method can be simplified to the comparison of the numbers of reported cases of the current and previous time steps. In spite of its simplicity, it can provide a good prediction for the spread of influenza in Japan.

  12. Young adults' trajectories of Ecstasy use: a population based study.

    Science.gov (United States)

    Smirnov, Andrew; Najman, Jake M; Hayatbakhsh, Reza; Plotnikova, Maria; Wells, Helene; Legosz, Margot; Kemp, Robert

    2013-11-01

    Young adults' Ecstasy use trajectories have important implications for individual and population-level consequences of Ecstasy use, but little relevant research has been conducted. This study prospectively examines Ecstasy trajectories in a population-based sample. Data are from the Natural History Study of Drug Use, a retrospective/prospective cohort study conducted in Australia. Population screening identified a probability sample of Ecstasy users aged 19-23 years. Complete data for 30 months of follow-up, comprising 4 time intervals, were available for 297 participants (88.4% of sample). Trajectories were derived using cluster analysis based on recent Ecstasy use at each interval. Trajectory predictors were examined using a generalized ordered logit model and included Ecstasy dependence (World Mental Health Composite International Diagnostic Instrument), psychological distress (Hospital Anxiety Depression Scale), aggression (Young Adult Self Report) and contextual factors (e.g. attendance at electronic/dance music events). Three Ecstasy trajectories were identified (low, intermediate and high use). At its peak, the high-use trajectory involved 1-2 days Ecstasy use per week. Decreasing frequency of use was observed for intermediate and high-use trajectories from 12 months, independently of market factors. Intermediate and high-use trajectory membership was predicted by past Ecstasy consumption (>70 pills) and attendance at electronic/dance music events. High-use trajectory members were unlikely to have used Ecstasy for more than 3 years and tended to report consistently positive subjective effects at baseline. Given the social context and temporal course of Ecstasy use, Ecstasy trajectories might be better understood in terms of instrumental rather than addictive drug use patterns. © 2013 Elsevier Ltd. All rights reserved.

  13. Computer Animation Based on Particle Methods

    Directory of Open Access Journals (Sweden)

    Rafal Wcislo

    1999-01-01

    Full Text Available The paper presents the main issues of a computer animation of a set of elastic macroscopic objects based on the particle method. The main assumption of the generated animations is to achieve very realistic movements in a scene observed on the computer display. The objects (solid bodies interact mechanically with each other, The movements and deformations of solids are calculated using the particle method. Phenomena connected with the behaviour of solids in the gravitational field, their defomtations caused by collisions and interactions with the optional liquid medium are simulated. The simulation ofthe liquid is performed using the cellular automata method. The paper presents both simulation schemes (particle method and cellular automata rules an the method of combining them in the single animation program. ln order to speed up the execution of the program the parallel version based on the network of workstation was developed. The paper describes the methods of the parallelization and it considers problems of load-balancing, collision detection, process synchronization and distributed control of the animation.

  14. ObStruct: a method to objectively analyse factors driving population structure using Bayesian ancestry profiles.

    Directory of Open Access Journals (Sweden)

    Velimir Gayevskiy

    Full Text Available Bayesian inference methods are extensively used to detect the presence of population structure given genetic data. The primary output of software implementing these methods are ancestry profiles of sampled individuals. While these profiles robustly partition the data into subgroups, currently there is no objective method to determine whether the fixed factor of interest (e.g. geographic origin correlates with inferred subgroups or not, and if so, which populations are driving this correlation. We present ObStruct, a novel tool to objectively analyse the nature of structure revealed in Bayesian ancestry profiles using established statistical methods. ObStruct evaluates the extent of structural similarity between sampled and inferred populations, tests the significance of population differentiation, provides information on the contribution of sampled and inferred populations to the observed structure and crucially determines whether the predetermined factor of interest correlates with inferred population structure. Analyses of simulated and experimental data highlight ObStruct's ability to objectively assess the nature of structure in populations. We show the method is capable of capturing an increase in the level of structure with increasing time since divergence between simulated populations. Further, we applied the method to a highly structured dataset of 1,484 humans from seven continents and a less structured dataset of 179 Saccharomyces cerevisiae from three regions in New Zealand. Our results show that ObStruct provides an objective metric to classify the degree, drivers and significance of inferred structure, as well as providing novel insights into the relationships between sampled populations, and adds a final step to the pipeline for population structure analyses.

  15. An evaluation of the methods of determining excited state population distributions from sputtering sources

    International Nuclear Information System (INIS)

    Snowdon, K.J.; Andresen, B.; Veje, E.

    1978-01-01

    The method of calculating relative initial level populations of excited states of sputtered atoms is developed in principle and compared with those in current use. The reason that the latter, although mathematically different, have generally led to similar population distributions is outlined. (Auth.)

  16. Disregarding population specificity: its influence on the sex assessment methods from the tibia

    Czech Academy of Sciences Publication Activity Database

    Kotěrová, A.; Velemínská, J.; Dupej, J.; Brzobohatá, Hana; Pilný, A.; Brůžek, J.

    2017-01-01

    Roč. 131, č. 1 (2017), s. 251-261 ISSN 0937-9827 Institutional support: RVO:67985912 Keywords : forensic anthropology population data * sex determination * tibia * population specificity * discriminant function analysis * GAME method Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology Impact factor: 2.382, year: 2016

  17. Application of homotopy-perturbation method to nonlinear population dynamics models

    International Nuclear Information System (INIS)

    Chowdhury, M.S.H.; Hashim, I.; Abdulaziz, O.

    2007-01-01

    In this Letter, the homotopy-perturbation method (HPM) is employed to derive approximate series solutions of nonlinear population dynamics models. The nonlinear models considered are the multispecies Lotka-Volterra equations. The accuracy of this method is examined by comparison with the available exact and the fourth-order Runge-Kutta method (RK4)

  18. A Population-based Survey of the Prevalence and Types of Glaucoma in Nepal: The Bhaktapur Glaucoma Study

    NARCIS (Netherlands)

    Thapa, S.S.; Paudyal, I.; Khanal, S.; Twyana, S.N.; Paudyal, G.; Gurung, R.; Ruit, S.; van Rens, G.H.M.B.

    2012-01-01

    Objective: To determine the prevalence and types of glaucoma in a Nepalese population. Design: Cross-sectional, population-based survey. Participants: A total of 4800 subjects aged 40 years or older from the Bhaktapur district of Kathmandu valley. Methods: Subjects aged 40 years or older were

  19. Population clustering based on copy number variations detected from next generation sequencing data.

    Science.gov (United States)

    Duan, Junbo; Zhang, Ji-Gang; Wan, Mingxi; Deng, Hong-Wen; Wang, Yu-Ping

    2014-08-01

    Copy number variations (CNVs) can be used as significant bio-markers and next generation sequencing (NGS) provides a high resolution detection of these CNVs. But how to extract features from CNVs and further apply them to genomic studies such as population clustering have become a big challenge. In this paper, we propose a novel method for population clustering based on CNVs from NGS. First, CNVs are extracted from each sample to form a feature matrix. Then, this feature matrix is decomposed into the source matrix and weight matrix with non-negative matrix factorization (NMF). The source matrix consists of common CNVs that are shared by all the samples from the same group, and the weight matrix indicates the corresponding level of CNVs from each sample. Therefore, using NMF of CNVs one can differentiate samples from different ethnic groups, i.e. population clustering. To validate the approach, we applied it to the analysis of both simulation data and two real data set from the 1000 Genomes Project. The results on simulation data demonstrate that the proposed method can recover the true common CNVs with high quality. The results on the first real data analysis show that the proposed method can cluster two family trio with different ancestries into two ethnic groups and the results on the second real data analysis show that the proposed method can be applied to the whole-genome with large sample size consisting of multiple groups. Both results demonstrate the potential of the proposed method for population clustering.

  20. Spike-based population coding and working memory.

    Directory of Open Access Journals (Sweden)

    Martin Boerlin

    2011-02-01

    Full Text Available Compelling behavioral evidence suggests that humans can make optimal decisions despite the uncertainty inherent in perceptual or motor tasks. A key question in neuroscience is how populations of spiking neurons can implement such probabilistic computations. In this article, we develop a comprehensive framework for optimal, spike-based sensory integration and working memory in a dynamic environment. We propose that probability distributions are inferred spike-per-spike in recurrently connected networks of integrate-and-fire neurons. As a result, these networks can combine sensory cues optimally, track the state of a time-varying stimulus and memorize accumulated evidence over periods much longer than the time constant of single neurons. Importantly, we propose that population responses and persistent working memory states represent entire probability distributions and not only single stimulus values. These memories are reflected by sustained, asynchronous patterns of activity which make relevant information available to downstream neurons within their short time window of integration. Model neurons act as predictive encoders, only firing spikes which account for new information that has not yet been signaled. Thus, spike times signal deterministically a prediction error, contrary to rate codes in which spike times are considered to be random samples of an underlying firing rate. As a consequence of this coding scheme, a multitude of spike patterns can reliably encode the same information. This results in weakly correlated, Poisson-like spike trains that are sensitive to initial conditions but robust to even high levels of external neural noise. This spike train variability reproduces the one observed in cortical sensory spike trains, but cannot be equated to noise. On the contrary, it is a consequence of optimal spike-based inference. In contrast, we show that rate-based models perform poorly when implemented with stochastically spiking neurons.

  1. The use of customised versus population-based birthweight standards in predicting perinatal mortality.

    Science.gov (United States)

    Zhang, X; Platt, R W; Cnattingius, S; Joseph, K S; Kramer, M S

    2007-04-01

    The objective of this study was to critically examine potential artifacts and biases underlying the use of 'customised' standards of birthweight for gestational age (GA). Population-based cohort study. Sweden. A total of 782,303 singletons > or =28 weeks of gestation born in 1992-2001 to Nordic mothers with complete data on birthweight; GA; and maternal age, parity, height, and pre-pregnancy weight. We compared perinatal mortality in four groups of infants based on the following classification of small for gestational age (SGA): non-SGA based on either population-based or customised standards (the reference group), SGA based on the population-based standard only, SGA based on the customised standard only, and SGA according to both standards. We used graphical methods to compare GA-specific birthweight cutoffs for SGA using the two standards and also used logistic regression to control for differences in GA and maternal pre-pregnancy body mass index (BMI) in the four groups. Perinatal mortality, including stillbirth and neonatal death. Customisation led to a large artifactual increase in the proportion of SGA infants born preterm. Adjustment for differences in GA and maternal BMI markedly reduced the excess risk among infants classified as SGA by customised standards only. The large increase in perinatal mortality risk among infants classified as SGA based on customised standards is largely an artifact due to inclusion of more preterm births.

  2. Counting hard-to-count populations: the network scale-up method for public health

    Science.gov (United States)

    Bernard, H Russell; Hallett, Tim; Iovita, Alexandrina; Johnsen, Eugene C; Lyerla, Rob; McCarty, Christopher; Mahy, Mary; Salganik, Matthew J; Saliuk, Tetiana; Scutelniciuc, Otilia; Shelley, Gene A; Sirinirund, Petchsri; Weir, Sharon

    2010-01-01

    Estimating sizes of hidden or hard-to-reach populations is an important problem in public health. For example, estimates of the sizes of populations at highest risk for HIV and AIDS are needed for designing, evaluating and allocating funding for treatment and prevention programmes. A promising approach to size estimation, relatively new to public health, is the network scale-up method (NSUM), involving two steps: estimating the personal network size of the members of a random sample of a total population and, with this information, estimating the number of members of a hidden subpopulation of the total population. We describe the method, including two approaches to estimating personal network sizes (summation and known population). We discuss the strengths and weaknesses of each approach and provide examples of international applications of the NSUM in public health. We conclude with recommendations for future research and evaluation. PMID:21106509

  3. Portable atomic frequency standard based on coherent population trapping

    Science.gov (United States)

    Shi, Fan; Yang, Renfu; Nian, Feng; Zhang, Zhenwei; Cui, Yongshun; Zhao, Huan; Wang, Nuanrang; Feng, Keming

    2015-05-01

    In this work, a portable atomic frequency standard based on coherent population trapping is designed and demonstrated. To achieve a portable prototype, in the system, a single transverse mode 795nm VCSEL modulated by a 3.4GHz RF source is used as a pump laser which generates coherent light fields. The pump beams pass through a vapor cell containing atom gas and buffer gas. This vapor cell is surrounded by a magnetic shield and placed inside a solenoid which applies a longitudinal magnetic field to lift the Zeeman energy levels' degeneracy and to separate the resonance signal, which has no first-order magnetic field dependence, from the field-dependent resonances. The electrical control system comprises two control loops. The first one locks the laser wavelength to the minimum of the absorption spectrum; the second one locks the modulation frequency and output standard frequency. Furthermore, we designed the micro physical package and realized the locking of a coherent population trapping atomic frequency standard portable prototype successfully. The short-term frequency stability of the whole system is measured to be 6×10-11 for averaging times of 1s, and reaches 5×10-12 at an averaging time of 1000s.

  4. A New Method for Deriving the Stellar Birth Function of Resolved Stellar Populations.

    Science.gov (United States)

    Gennaro, M.; Tchernyshyov, K.; Brown, T. M.; Gordon, K. D.

    2015-07-01

    We present a new method for deriving the stellar birth function (SBF) of resolved stellar populations. The SBF (stars born per unit mass, time, and metallicity) is the combination of the initial mass function (IMF), the star formation history (SFH), and the metallicity distribution function (MDF). The framework of our analysis is that of Poisson Point Processes (PPPs), a class of statistical models suitable when dealing with points (stars) in a multidimensional space (the measurement space of multiple photometric bands). The theory of PPPs easily accommodates the modeling of measurement errors as well as that of incompleteness. Our method avoids binning stars in the color-magnitude diagram and uses the whole likelihood function for each data point; combining the individual likelihoods allows the computation of the posterior probability for the population's SBF. Within the proposed framework it is possible to include nuisance parameters, such as distance and extinction, by specifying their prior distributions and marginalizing over them. The aim of this paper is to assess the validity of this new approach under a range of assumptions, using only simulated data. Forthcoming work will show applications to real data. Although it has a broad scope of possible applications, we have developed this method to study multi-band Hubble Space Telescope observations of the Milky Way Bulge. Therefore we will focus on simulations with characteristics similar to those of the Galactic Bulge. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at STScI, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  5. Comorbidity profile of poliomyelitis survivors in a Chinese population: a population-based study.

    Science.gov (United States)

    Kang, Jiunn-Horng; Lin, Herng-Ching

    2011-06-01

    Previous reports of comorbid conditions in poliomyelitis survivors mainly focused on some disease categories, such as respiratory diseases, gastrointestinal diseases, psychiatric diseases, neurological diseases and cancer. Data regarding a wide spectrum of medical comorbidities in patients with poliomyelitis is still sparse. This study aimed to investigate and profile the wide range of comorbidities among the survivors of paralytic poliomyelitis in a Chinese population. In total, 2,032 paralytic poliomyelitis patients were selected as the study group and the comparison group consisted of 10,160 randomly selected enrollees. The comorbidities for analysis were based on a modified version of the Elixhauser Comorbidity Index. Conditional logistic regression analyses were computed to investigate the risk of comorbidities for these two groups. As compared to controls, patients with paralytic poliomyelitis had significantly higher prevalence of hypertension, ischemic heart disease, hyperlipidemia, congestive heart failure, cardiac arrhythmias, peripheral vascular disorder, stroke, paralysis, migraines, Parkinson's disease, rheumatoid arthritis, ankylosing spondylitis, pulmonary circulation disorders, chronic pulmonary disease, liver disease, peptic ulcers, hepatitis B or C, deficiency anemias, depression, and lymphoma. Most of the differences are of clinical interest, ORs often being between 2 and 3. No significant difference between poliomyelitis patients and controls was observed in the prevalence of SLE, tuberculosis, alcohol abuse and drug abuse. Our findings demonstrate that survivors of paralytic poliomyelitis in Taiwan are at higher risk of having multiple medical comorbidities although some potential confounding factors including educational level, marital status, obesity and physical activity are not available in our database. The pattern is generally consistent with previous observations from Western populations. Nevertheless, we found several novel associations

  6. New technology-based recruitment methods

    OpenAIRE

    Oksanen, Reija

    2018-01-01

    The transformation that recruitment might encounter due to big data analytics and artificial intelligence (AI) is particularly fascinating which is why this thesis focuses on the changes recruitment processes are and will be facing as new technological solutions are emerging. The aim and main objective of this study is to widen knowledge about new technology-based recruitment methods, focusing on how they are utilized by Finnish recruitment professionals and how the opportunities and risks th...

  7. Long-term response to genomic selection: effects of estimation method and reference population structure for different genetic architectures.

    Science.gov (United States)

    Bastiaansen, John W M; Coster, Albart; Calus, Mario P L; van Arendonk, Johan A M; Bovenhuis, Henk

    2012-01-24

    Genomic selection has become an important tool in the genetic improvement of animals and plants. The objective of this study was to investigate the impacts of breeding value estimation method, reference population structure, and trait genetic architecture, on long-term response to genomic selection without updating marker effects. Three methods were used to estimate genomic breeding values: a BLUP method with relationships estimated from genome-wide markers (GBLUP), a Bayesian method, and a partial least squares regression method (PLSR). A shallow (individuals from one generation) or deep reference population (individuals from five generations) was used with each method. The effects of the different selection approaches were compared under four different genetic architectures for the trait under selection. Selection was based on one of the three genomic breeding values, on pedigree BLUP breeding values, or performed at random. Selection continued for ten generations. Differences in long-term selection response were small. For a genetic architecture with a very small number of three to four quantitative trait loci (QTL), the Bayesian method achieved a response that was 0.05 to 0.1 genetic standard deviation higher than other methods in generation 10. For genetic architectures with approximately 30 to 300 QTL, PLSR (shallow reference) or GBLUP (deep reference) had an average advantage of 0.2 genetic standard deviation over the Bayesian method in generation 10. GBLUP resulted in 0.6% and 0.9% less inbreeding than PLSR and BM and on average a one third smaller reduction of genetic variance. Responses in early generations were greater with the shallow reference population while long-term response was not affected by reference population structure. The ranking of estimation methods was different with than without selection. Under selection, applying GBLUP led to lower inbreeding and a smaller reduction of genetic variance while a similar response to selection was

  8. Screening for type 2 diabetes in a high-risk population: Study design and feasibility of a population-based randomized controlled trial

    NARCIS (Netherlands)

    B. Klijs (Bart); S.J. Otto (Suzie); R.J. Heine (Robert); Y. van der Graaf (Yolanda); J.J. Lous (Jan); H.J. de Koning (Harry)

    2012-01-01

    textabstractBackground: We describe the design and present the results of the first year of a population-based study of screening for type 2 diabetes in individuals at high risk of developing the disease. High risk is defined as having abdominal obesity. Methods. Between 2006 and 2007, 79,142

  9. Screening for type 2 diabetes in a high-risk population: study design and feasibility of a population-based randomized controlled trial

    NARCIS (Netherlands)

    Klijs, B.; Otto, S.J.; Heine, R.J.; van der Graaf, Y.; Lous, J.J.; Koning, H.J.

    2012-01-01

    Background: We describe the design and present the results of the first year of a population-based study of screening for type 2 diabetes in individuals at high risk of developing the disease. High risk is defined as having abdominal obesity. Methods. Between 2006 and 2007, 79,142 inhabitants of two

  10. Application of Holt exponential smoothing and ARIMA method for data population in West Java

    Science.gov (United States)

    Supriatna, A.; Susanti, D.; Hertini, E.

    2017-01-01

    One method of time series that is often used to predict data that contains trend is Holt. Holt method using different parameters used in the original data which aims to smooth the trend value. In addition to Holt, ARIMA method can be used on a wide variety of data including data pattern containing a pattern trend. Data actual of population from 1998-2015 contains the trends so can be solved by Holt and ARIMA method to obtain the prediction value of some periods. The best method is measured by looking at the smallest MAPE and MAE error. The result using Holt method is 47.205.749 populations in 2016, 47.535.324 populations in 2017, and 48.041.672 populations in 2018, with MAPE error is 0,469744 and MAE error is 189.731. While the result using ARIMA method is 46.964.682 populations in 2016, 47.342.189 in 2017, and 47.899.696 in 2018, with MAPE error is 0,4380 and MAE is 176.626.

  11. Outline-based morphometrics, an overlooked method in arthropod studies?

    Science.gov (United States)

    Dujardin, Jean-Pierre; Kaba, D; Solano, P; Dupraz, M; McCoy, K D; Jaramillo-O, N

    2014-12-01

    Modern methods allow a geometric representation of forms, separating size and shape. In entomology, as well as in many other fields involving arthropod studies, shape variation has proved useful for species identification and population characterization. In medical entomology, it has been applied to very specific questions such as population structure, reinfestation of insecticide-treated areas and cryptic species recognition. For shape comparisons, great importance is given to the quality of landmarks in terms of comparability. Two conceptually and statistically separate approaches are: (i) landmark-based morphometrics, based on the relative position of a few anatomical "true" or "traditional" landmarks, and (ii) outline-based morphometrics, which captures the contour of forms through a sequence of close "pseudo-landmarks". Most of the studies on insects of medical, veterinary or economic importance make use of the landmark approach. The present survey makes a case for the outline method, here based on elliptic Fourier analysis. The collection of pseudo-landmarks may require the manual digitization of many points and, for this reason, might appear less attractive. It, however, has the ability to compare homologous organs or structures having no landmarks at all. This strength offers the possibility to study a wider range of anatomical structures and thus, a larger range of arthropods. We present a few examples highlighting its interest for separating close or cryptic species, or characterizing conspecific geographic populations, in a series of different vector organisms. In this simple application, i.e. the recognition of close or cryptic forms, the outline approach provided similar scores as those obtained by the landmark-based approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. A framework for comparative evaluation of dosimetric methods to triage a large population following a radiological event

    International Nuclear Information System (INIS)

    Flood, Ann Barry; Nicolalde, Roberto J.; Demidenko, Eugene; Williams, Benjamin B.; Shapiro, Alla; Wiley, Albert L.; Swartz, Harold M.

    2011-01-01

    Background: To prepare for a possible major radiation disaster involving large numbers of potentially exposed people, it is important to be able to rapidly and accurately triage people for treatment or not, factoring in the likely conditions and available resources. To date, planners have had to create guidelines for triage based on methods for estimating dose that are clinically available and which use evidence extrapolated from unrelated conditions. Current guidelines consequently focus on measuring clinical symptoms (e.g., time-to-vomiting), which may not be subject to the same verification of standard methods and validation processes required for governmental approval processes of new and modified procedures. Biodosimeters under development have not yet been formally approved for this use. Neither set of methods has been tested in settings involving large-scale populations at risk for exposure. Objective: To propose a framework for comparative evaluation of methods for such triage and to evaluate biodosimetric methods that are currently recommended and new methods as they are developed. Methods: We adapt the NIH model of scientific evaluations and sciences needed for effective translational research to apply to biodosimetry for triaging very large populations following a radiation event. We detail criteria for translating basic science about dosimetry into effective multi-stage triage of large populations and illustrate it by analyzing 3 current guidelines and 3 advanced methods for biodosimetry. Conclusions: This framework for evaluating dosimetry in large populations is a useful technique to compare the strengths and weaknesses of different dosimetry methods. It can help policy-makers and planners not only to compare the methods' strengths and weaknesses for their intended use but also to develop an integrated approach to maximize their effectiveness. It also reveals weaknesses in methods that would benefit from further research and evaluation.

  13. A framework for comparative evaluation of dosimetric methods to triage a large population following a radiological event

    Energy Technology Data Exchange (ETDEWEB)

    Flood, Ann Barry, E-mail: Ann.B.Flood@Dartmouth.Edu [Dartmouth Physically Based Biodosimetry Center for Medical Countermeasures Against Radiation (Dart-Dose CMCR), Dartmouth Medical School, Hanover, NH 03768 (United States); Nicolalde, Roberto J., E-mail: Roberto.J.Nicolalde@Dartmouth.Edu [Dartmouth Physically Based Biodosimetry Center for Medical Countermeasures Against Radiation (Dart-Dose CMCR), Dartmouth Medical School, Hanover, NH 03768 (United States); Demidenko, Eugene, E-mail: Eugene.Demidenko@Dartmouth.Edu [Dartmouth Physically Based Biodosimetry Center for Medical Countermeasures Against Radiation (Dart-Dose CMCR), Dartmouth Medical School, Hanover, NH 03768 (United States); Williams, Benjamin B., E-mail: Benjamin.B.Williams@Dartmouth.Edu [Dartmouth Physically Based Biodosimetry Center for Medical Countermeasures Against Radiation (Dart-Dose CMCR), Dartmouth Medical School, Hanover, NH 03768 (United States); Shapiro, Alla, E-mail: Alla.Shapiro@fda.hhs.gov [Food and Drug Administration (FDA), Rockville, MD (United States); Wiley, Albert L., E-mail: Albert.Wiley@orise.orau.gov [Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN (United States); Swartz, Harold M., E-mail: Harold.M.Swartz@Dartmouth.Edu [Dartmouth Physically Based Biodosimetry Center for Medical Countermeasures Against Radiation (Dart-Dose CMCR), Dartmouth Medical School, Hanover, NH 03768 (United States)

    2011-09-15

    Background: To prepare for a possible major radiation disaster involving large numbers of potentially exposed people, it is important to be able to rapidly and accurately triage people for treatment or not, factoring in the likely conditions and available resources. To date, planners have had to create guidelines for triage based on methods for estimating dose that are clinically available and which use evidence extrapolated from unrelated conditions. Current guidelines consequently focus on measuring clinical symptoms (e.g., time-to-vomiting), which may not be subject to the same verification of standard methods and validation processes required for governmental approval processes of new and modified procedures. Biodosimeters under development have not yet been formally approved for this use. Neither set of methods has been tested in settings involving large-scale populations at risk for exposure. Objective: To propose a framework for comparative evaluation of methods for such triage and to evaluate biodosimetric methods that are currently recommended and new methods as they are developed. Methods: We adapt the NIH model of scientific evaluations and sciences needed for effective translational research to apply to biodosimetry for triaging very large populations following a radiation event. We detail criteria for translating basic science about dosimetry into effective multi-stage triage of large populations and illustrate it by analyzing 3 current guidelines and 3 advanced methods for biodosimetry. Conclusions: This framework for evaluating dosimetry in large populations is a useful technique to compare the strengths and weaknesses of different dosimetry methods. It can help policy-makers and planners not only to compare the methods' strengths and weaknesses for their intended use but also to develop an integrated approach to maximize their effectiveness. It also reveals weaknesses in methods that would benefit from further research and evaluation.

  14. A multicore based parallel image registration method.

    Science.gov (United States)

    Yang, Lin; Gong, Leiguang; Zhang, Hong; Nosher, John L; Foran, David J

    2009-01-01

    Image registration is a crucial step for many image-assisted clinical applications such as surgery planning and treatment evaluation. In this paper we proposed a landmark based nonlinear image registration algorithm for matching 2D image pairs. The algorithm was shown to be effective and robust under conditions of large deformations. In landmark based registration, the most important step is establishing the correspondence among the selected landmark points. This usually requires an extensive search which is often computationally expensive. We introduced a nonregular data partition algorithm using the K-means clustering algorithm to group the landmarks based on the number of available processing cores. The step optimizes the memory usage and data transfer. We have tested our method using IBM Cell Broadband Engine (Cell/B.E.) platform.

  15. EpiReumaPt: how to perform a national population based study - a practical guide

    OpenAIRE

    Gouveia, Nélia; Rodrigues, Ana M.; Ramiro, Sofia; Machado, Pedro; Da Costa, Leonor Pereira; Mourão, Ana Filipa; Silva, Inês; Rego, Tânia; Laires, Pedro; André, Rui; Mauricio, Luís; Romeu, José Carlos; Tavares, Viviana; Cerol, Jorge; Canhão, Helena

    2015-01-01

    BACKGROUND: The aim of this article was to describe and discuss several strategies and standard operating procedures undertaken in the EpiReumaPt study - which was the first Portuguese, national, cross-sectional population-based study of Rheumatic and Musculoskeletal Diseases (RMD). METHODS: The technical procedures, legal issues, management and practical questions were studied, analyzed and discussed with relevant stakeholders. During the 1st phase of EpiReumaPt the coordination team and Cen...

  16. Increased migraine risk in osteoporosis patients: a nationwide population-based study

    OpenAIRE

    Wu, Chieh-Hsin; Zhang, Zi-Hao; Wu, Ming-Kung; Wang, Chiu-Huan; Lu, Ying-Yi; Lin, Chih-Lung

    2016-01-01

    Background Osteoporosis and migraine are both important public health problems and may have overlapping pathophysiological mechanisms. The aim of this study was to use a Taiwanese population-based dataset to assess migraine risk in osteoporosis patients. Methods The Taiwan National Health Insurance Research Database was used to analyse data for 40,672 patients aged ?20?years who had been diagnosed with osteoporosis during 1996?2010. An additional 40,672 age-matched patients without osteoporos...

  17. Dietary patterns associated with fall-related fracture in elderly Japanese: a population based prospective study

    OpenAIRE

    Monma, Yasutake; Niu, Kaijun; Iwasaki, Koh; Tomita, Naoki; Nakaya, Naoki; Hozawa, Atsushi; Kuriyama, Shinichi; Takayama, Shin; Seki, Takashi; Takeda, Takashi; Yaegashi, Nobuo; Ebihara, Satoru; Arai, Hiroyuki; Nagatomi, Ryoichi; Tsuji, Ichiro

    2010-01-01

    Abstract Background Diet is considered an important factor for bone health, but is composed of a wide variety of foods containing complex combinations of nutrients. Therefore we investigated the relationship between dietary patterns and fall-related fractures in the elderly. Methods We designed a population-based prospective survey of 1178 elderly people in Japan in 2002. Dietary intake was assessed with a 75-item food frequency questionnaire (FFQ), from which dietary patterns were created by...

  18. Profiles of sedentary and non-sedentary young men ? a population-based MOPO study

    OpenAIRE

    Pyky, Riitta; Jauho, Anna-Maiju; Ahola, Riikka; Ik?heimo, Tiina M.; Koivumaa-Honkanen, Heli; M?ntysaari, Matti; J?ms?, Timo; Korpelainen, Raija

    2015-01-01

    Background Sedentary behavior is associated with poor well-being in youth with adverse trajectories spanning to adulthood. Still, its determinants are poorly known. Our aim was to profile sedentary and non-sedentary young men and to clarify their differences in a population-based setting. Methods A total of 616 men (mean age 17.9, SD 0.6) attending compulsory conscription for military service completed a questionnaire on health, health behavior, socioeconomic situation and media use. They und...

  19. A general method to determine sampling windows for nonlinear mixed effects models with an application to population pharmacokinetic studies.

    Science.gov (United States)

    Foo, Lee Kien; McGree, James; Duffull, Stephen

    2012-01-01

    Optimal design methods have been proposed to determine the best sampling times when sparse blood sampling is required in clinical pharmacokinetic studies. However, the optimal blood sampling time points may not be feasible in clinical practice. Sampling windows, a time interval for blood sample collection, have been proposed to provide flexibility in blood sampling times while preserving efficient parameter estimation. Because of the complexity of the population pharmacokinetic models, which are generally nonlinear mixed effects models, there is no analytical solution available to determine sampling windows. We propose a method for determination of sampling windows based on MCMC sampling techniques. The proposed method attains a stationary distribution rapidly and provides time-sensitive windows around the optimal design points. The proposed method is applicable to determine sampling windows for any nonlinear mixed effects model although our work focuses on an application to population pharmacokinetic models. Copyright © 2012 John Wiley & Sons, Ltd.

  20. Lagrangian based methods for coherent structure detection

    Energy Technology Data Exchange (ETDEWEB)

    Allshouse, Michael R., E-mail: mallshouse@chaos.utexas.edu [Center for Nonlinear Dynamics and Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States); Peacock, Thomas, E-mail: tomp@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2015-09-15

    There has been a proliferation in the development of Lagrangian analytical methods for detecting coherent structures in fluid flow transport, yielding a variety of qualitatively different approaches. We present a review of four approaches and demonstrate the utility of these methods via their application to the same sample analytic model, the canonical double-gyre flow, highlighting the pros and cons of each approach. Two of the methods, the geometric and probabilistic approaches, are well established and require velocity field data over the time interval of interest to identify particularly important material lines and surfaces, and influential regions, respectively. The other two approaches, implementing tools from cluster and braid theory, seek coherent structures based on limited trajectory data, attempting to partition the flow transport into distinct regions. All four of these approaches share the common trait that they are objective methods, meaning that their results do not depend on the frame of reference used. For each method, we also present a number of example applications ranging from blood flow and chemical reactions to ocean and atmospheric flows.

  1. Determining individual variation in growth and its implication for life-history and population processes using the empirical Bayes method.

    Directory of Open Access Journals (Sweden)

    Simone Vincenzi

    2014-09-01

    Full Text Available The differences in demographic and life-history processes between organisms living in the same population have important consequences for ecological and evolutionary dynamics. Modern statistical and computational methods allow the investigation of individual and shared (among homogeneous groups determinants of the observed variation in growth. We use an Empirical Bayes approach to estimate individual and shared variation in somatic growth using a von Bertalanffy growth model with random effects. To illustrate the power and generality of the method, we consider two populations of marble trout Salmo marmoratus living in Slovenian streams, where individually tagged fish have been sampled for more than 15 years. We use year-of-birth cohort, population density during the first year of life, and individual random effects as potential predictors of the von Bertalanffy growth function's parameters k (rate of growth and L∞ (asymptotic size. Our results showed that size ranks were largely maintained throughout marble trout lifetime in both populations. According to the Akaike Information Criterion (AIC, the best models showed different growth patterns for year-of-birth cohorts as well as the existence of substantial individual variation in growth trajectories after accounting for the cohort effect. For both populations, models including density during the first year of life showed that growth tended to decrease with increasing population density early in life. Model validation showed that predictions of individual growth trajectories using the random-effects model were more accurate than predictions based on mean size-at-age of fish.

  2. Determining individual variation in growth and its implication for life-history and population processes using the empirical Bayes method.

    Science.gov (United States)

    Vincenzi, Simone; Mangel, Marc; Crivelli, Alain J; Munch, Stephan; Skaug, Hans J

    2014-09-01

    The differences in demographic and life-history processes between organisms living in the same population have important consequences for ecological and evolutionary dynamics. Modern statistical and computational methods allow the investigation of individual and shared (among homogeneous groups) determinants of the observed variation in growth. We use an Empirical Bayes approach to estimate individual and shared variation in somatic growth using a von Bertalanffy growth model with random effects. To illustrate the power and generality of the method, we consider two populations of marble trout Salmo marmoratus living in Slovenian streams, where individually tagged fish have been sampled for more than 15 years. We use year-of-birth cohort, population density during the first year of life, and individual random effects as potential predictors of the von Bertalanffy growth function's parameters k (rate of growth) and L∞ (asymptotic size). Our results showed that size ranks were largely maintained throughout marble trout lifetime in both populations. According to the Akaike Information Criterion (AIC), the best models showed different growth patterns for year-of-birth cohorts as well as the existence of substantial individual variation in growth trajectories after accounting for the cohort effect. For both populations, models including density during the first year of life showed that growth tended to decrease with increasing population density early in life. Model validation showed that predictions of individual growth trajectories using the random-effects model were more accurate than predictions based on mean size-at-age of fish.

  3. Epidemiology of benign paroxysmal positional vertigo: a population based study

    Science.gov (United States)

    von Brevern, M; Radtke, A; Lezius, F; Feldmann, M; Ziese, T; Lempert, T; Neuhauser, H

    2007-01-01

    Objectives To examine the prevalence and incidence, clinical presentation, societal impact and comorbid conditions of benign paroxysmal positional vertigo (BPPV) in the general population. Methods Cross‐sectional, nationally representative neurotological survey of the general adult population in Germany with a two stage sampling design: screening of 4869 participants from the German National Telephone Health Interview Survey 2003 (response rate 52%) for moderate or severe dizziness or vertigo, followed by validated neurotological interviews (n = 1003; response rate 87%). Diagnostic criteria for BPPV were at least five attacks of vestibular vertigo lasting <1 min without concomitant neurological symptoms and invariably provoked by typical changes in head position. In a concurrent validation study (n = 61) conducted in two specialised dizziness clinics, BPPV was detected by our telephone interview with a specificity of 92% and a sensitivity of 88% (positive predictive value 88%, negative predictive value 92%). Results BPPV accounted for 8% of individuals with moderate or severe dizziness/vertigo. The lifetime prevalence of BPPV was 2.4%, the 1 year prevalence was 1.6% and the 1 year incidence was 0.6%. The median duration of an episode was 2 weeks. In 86% of affected individuals, BPPV led to medical consultation, interruption of daily activities or sick leave. In total, only 8% of affected participants received effective treatment. On multivariate analysis, age, migraine, hypertension, hyperlipidaemia and stroke were independently associated with BPPV. Conclusion BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact and medical costs. PMID:17135456

  4. Cataract surgery in a population-based cohort of patients with type 1 diabetes

    DEFF Research Database (Denmark)

    Grauslund, Jakob; Green, Anders; Sjølie, Anne K

    2011-01-01

    .05-3.40) were the only statistically significant predictors of cataract surgery. Duration of diabetes, gender, glycaemic regulation, proteinuria, smoking, blood pressure and level of retinopathy were not associated with cataract surgery. Conclusion: Type 1 diabetes is associated with a high long-term incidence......ABSTRACT. Purpose: To estimate the long-term cumulative incidence of cataract surgery and associated risk factors in a 25-year follow-up of a population-based cohort of patients with type 1 diabetes. Methods: Based on insulin prescriptions, a population-based cohort of 727 patients with type 1...... of surgery were 59.3 and 42 years, respectively. Cataract surgery in the cohort took place approximately 20 years earlier compared to non-diabetic persons. In a multivariate regression analysis, baseline age [hazard ratio (HR) 1.89 per 10 years, 95% CI 1.46-2.27] and maculopathy (HR 1.89, 95% CI 1...

  5. Primary mucinous carcinoma of the skin: a population-based study

    DEFF Research Database (Denmark)

    Breiting, L.; Dahlstrom, K.; Breiting, V.

    2008-01-01

    Background Primary mucinous carcinoma of the skin (PMCS) is a rare malignant tumor deriving from the sweat glands. It is typically located on the head and is often mistaken for a metastasis from a more common primary tumor of the breast or gastrointestinal tract. We present the first population......-based study of PMCS. Materials and methods Data on PMCS was obtained from the Danish Cancer Registry, which has recorded incident cases of cancer on a nationwide basis since 1943. We extracted all patients diagnosed 1978-2003 with PMCS. Results Fifteen cases of PMCS have been registered during the study...... or PMCS related deaths were reported. Conclusion PMCS is a rare, slow-growing tumor which rarely metastasizes and is associated with low mortality. The age-standardized incidence rate, based on data from a population-based cancer registry of high quality and validity, is less than 0.1 per million. However...

  6. Sampling Methods and the Accredited Population in Athletic Training Education Research

    Science.gov (United States)

    Carr, W. David; Volberding, Jennifer

    2009-01-01

    Context: We describe methods of sampling the widely-studied, yet poorly defined, population of accredited athletic training education programs (ATEPs). Objective: There are two purposes to this study; first to describe the incidence and types of sampling methods used in athletic training education research, and second to clearly define the…

  7. Searching for Rigour in the Reporting of Mixed Methods Population Health Research: A Methodological Review

    Science.gov (United States)

    Brown, K. M.; Elliott, S. J.; Leatherdale, S. T.; Robertson-Wilson, J.

    2015-01-01

    The environments in which population health interventions occur shape both their implementation and outcomes. Hence, when evaluating these interventions, we must explore both intervention content and context. Mixed methods (integrating quantitative and qualitative methods) provide this opportunity. However, although criteria exist for establishing…

  8. Accuracy, precision, and economic efficiency for three methods of thrips (Thysanoptera: Thripidae) population density assessment.

    Science.gov (United States)

    Sutherland, Andrew M; Parrella, Michael P

    2011-08-01

    Western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), is a major horticultural pest and an important vector of plant viruses in many parts of the world. Methods for assessing thrips population density for pest management decision support are often inaccurate or imprecise due to thrips' positive thigmotaxis, small size, and naturally aggregated populations. Two established methods, flower tapping and an alcohol wash, were compared with a novel method, plant desiccation coupled with passive trapping, using accuracy, precision and economic efficiency as comparative variables. Observed accuracy was statistically similar and low (37.8-53.6%) for all three methods. Flower tapping was the least expensive method, in terms of person-hours, whereas the alcohol wash method was the most expensive. Precision, expressed by relative variation, depended on location within the greenhouse, location on greenhouse benches, and the sampling week, but it was generally highest for the flower tapping and desiccation methods. Economic efficiency, expressed by relative net precision, was highest for the flower tapping method and lowest for the alcohol wash method. Advantages and disadvantages are discussed for all three methods used. If relative density assessment methods such as these can all be assumed to accurately estimate a constant proportion of absolute density, then high precision becomes the methodological goal in terms of measuring insect population density, decision making for pest management, and pesticide efficacy assessments.

  9. Machine Learning Based Classification of Microsatellite Variation: An Effective Approach for Phylogeographic Characterization of Olive Populations.

    Science.gov (United States)

    Torkzaban, Bahareh; Kayvanjoo, Amir Hossein; Ardalan, Arman; Mousavi, Soraya; Mariotti, Roberto; Baldoni, Luciana; Ebrahimie, Esmaeil; Ebrahimi, Mansour; Hosseini-Mazinani, Mehdi

    2015-01-01

    Finding efficient analytical techniques is overwhelmingly turning into a bottleneck for the effectiveness of large biological data. Machine learning offers a novel and powerful tool to advance classification and modeling solutions in molecular biology. However, these methods have been less frequently used with empirical population genetics data. In this study, we developed a new combined approach of data analysis using microsatellite marker data from our previous studies of olive populations using machine learning algorithms. Herein, 267 olive accessions of various origins including 21 reference cultivars, 132 local ecotypes, and 37 wild olive specimens from the Iranian plateau, together with 77 of the most represented Mediterranean varieties were investigated using a finely selected panel of 11 microsatellite markers. We organized data in two '4-targeted' and '16-targeted' experiments. A strategy of assaying different machine based analyses (i.e. data cleaning, feature selection, and machine learning classification) was devised to identify the most informative loci and the most diagnostic alleles to represent the population and the geography of each olive accession. These analyses revealed microsatellite markers with the highest differentiating capacity and proved efficiency for our method of clustering olive accessions to reflect upon their regions of origin. A distinguished highlight of this study was the discovery of the best combination of markers for better differentiating of populations via machine learning models, which can be exploited to distinguish among other biological populations.

  10. An assembly sequence planning method based on composite algorithm

    Directory of Open Access Journals (Sweden)

    Enfu LIU

    2016-02-01

    Full Text Available To solve the combination explosion problem and the blind searching problem in assembly sequence planning of complex products, an assembly sequence planning method based on composite algorithm is proposed. In the composite algorithm, a sufficient number of feasible assembly sequences are generated using formalization reasoning algorithm as the initial population of genetic algorithm. Then fuzzy knowledge of assembly is integrated into the planning process of genetic algorithm and ant algorithm to get the accurate solution. At last, an example is conducted to verify the feasibility of composite algorithm.

  11. A Population-based survey of risk for cancer in individuals diagnosed with myotonic dystrophy

    Science.gov (United States)

    Abbott, Diana; Johnson, Nicholas E; Cannon-Albright, Lisa A.

    2018-01-01

    Introduction The risk of cancer in patients diagnosed with myotonic dystrophy (DM) is reported for the homogeneous Utah population. Methods Clinical data accessed from the largest Utah healthcare providers have been record-linked to the Utah Population Database (UPDB), a population-based resource also linked to the Utah Cancer Registry. Relative risks were estimated for 36 cancers of different types in 281 DM patients. Results Testicular cancer (RR=10.74; 95% CI: 1.91, 38.79), endometrial cancer (6.98; 1.24, 25.22), and Non-Hodgkins lymphoma (4.25; 1.16, 12.43) were all observed at significant excess in DM patients. Discussion This study confirms an overall increased risk of cancer in DM. Individuals diagnosed with DM might benefit from risk counseling. PMID:27064430

  12. Contact dermatitis to hair dyes in a Danish adult population: an interview-based study

    DEFF Research Database (Denmark)

    Søsted, H; Hesse, U; Menné, T

    2005-01-01

    BACKGROUND: Contact allergy to hair dye ingredients is a well-known entity seen both in consumers using hair dyes and among hairdressers with occupational contact dermatitis. Surveys show that consumers with even severe adverse skin reactions to hair dyes only rarely contact the healthcare services....... The frequency of hair dye-induced skin reactions in the consumer population is unknown. OBJECTIVES: An epidemiological investigation with the aim of establishing the proportion of hair dye-induced skin reactions was performed in a population-based sample. METHODS: A representative random sample (n = 4000......) was taken of the Danish adult population. Personal interview questions were asked regarding adverse skin reactions to hair dyes, either compatible with a classical allergic eczematous reaction with redness, scaling and itching or a severe allergic reaction with oedema of the forehead and face. The response...

  13. Multiple data sources improve DNA-based mark-recapture population estimates of grizzly bears.

    Science.gov (United States)

    Boulanger, John; Kendall, Katherine C; Stetz, Jeffrey B; Roon, David A; Waits, Lisette P; Paetkau, David

    2008-04-01

    A fundamental challenge to estimating population size with mark-recapture methods is heterogeneous capture probabilities and subsequent bias of population estimates. Confronting this problem usually requires substantial sampling effort that can be difficult to achieve for some species, such as carnivores. We developed a methodology that uses two data sources to deal with heterogeneity and applied this to DNA mark-recapture data from grizzly bears (Ursus arctos). We improved population estimates by incorporating additional DNA "captures" of grizzly bears obtained by collecting hair from unbaited bear rub trees concurrently with baited, grid-based, hair snag sampling. We consider a Lincoln-Petersen estimator with hair snag captures as the initial session and rub tree captures as the recapture session and develop an estimator in program MARK that treats hair snag and rub tree samples as successive sessions. Using empirical data from a large-scale project in the greater Glacier National Park, Montana, USA, area and simulation modeling we evaluate these methods and compare the results to hair-snag-only estimates. Empirical results indicate that, compared with hair-snag-only data, the joint hair-snag-rub-tree methods produce similar but more precise estimates if capture and recapture rates are reasonably high for both methods. Simulation results suggest that estimators are potentially affected by correlation of capture probabilities between sample types in the presence of heterogeneity. Overall, closed population Huggins-Pledger estimators showed the highest precision and were most robust to sparse data, heterogeneity, and capture probability correlation among sampling types. Results also indicate that these estimators can be used when a segment of the population has zero capture probability for one of the methods. We propose that this general methodology may be useful for other species in which mark-recapture data are available from multiple sources.

  14. Somatic symptom profiles in the general population: a latent class analysis in a Danish population-based health survey

    Directory of Open Access Journals (Sweden)

    Eliasen M

    2017-08-01

    Full Text Available Marie Eliasen,1 Torben Jørgensen,1–3 Andreas Schröder,4 Thomas Meinertz Dantoft,1 Per Fink,4 Chalotte Heinsvig Poulsen,1,5 Nanna Borup Johansen,1 Lene Falgaard Eplov,5 Sine Skovbjerg,1 Svend Kreiner2 1Research Centre for Prevention and Health, Centre for Health, The Capital Region of Denmark, Glostrup, 2Department of Public Health, University of Copenhagen, Copenhagen, 3Department of Clinical Medicine, Aalborg University, Aalborg, 4Research Clinic for Functional Disorders and Psychosomatics, Aarhus University Hospital, Aarhus C, 5Mental Health Centre Copenhagen, The Capital Region of Denmark, Hellerup, Denmark Purpose: The aim of this study was to identify and describe somatic symptom profiles in the general adult population in order to enable further epidemiological research within multiple somatic symptoms.Methods: Information on 19 self-reported common somatic symptoms was achieved from a population-based questionnaire survey of 36,163 randomly selected adults in the Capital Region of Denmark (55.4% women. The participants stated whether they had been considerably bothered by each symptom within 14 days prior to answering the questionnaire. We used latent class analysis to identify the somatic symptom profiles. The profiles were further described by their association with age, sex, chronic disease, and self-perceived health.Results: We identified 10 different somatic symptom profiles defined by number, type, and site of the symptoms. The majority of the population (74.0% had a profile characterized by no considerable bothering symptoms, while a minor group of 3.9% had profiles defined by a high risk of multiple somatic symptoms. The remaining profiles were more likely to be characterized by a few specific symptoms. The profiles could further be described by their associations with age, sex, chronic disease, and self-perceived health.Conclusion: The identified somatic symptom profiles could be distinguished by number, type, and site of

  15. Occupational risk and chronic kidney disease: a population-based study in the United States adult population

    Directory of Open Access Journals (Sweden)

    Rubinstein S

    2013-03-01

    Full Text Available Sofia Rubinstein,1 Chengwei Wang,1 Wenchun Qu2 1Department of Medicine, Nassau University Medical Center, East Meadow, NY, USA; 2Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA Objective: Previous studies on occupational risk for chronic kidney disease (CKD have analyzed a limited range of occupations and focused on nephrotoxins. The primary purpose of this study was to examine the relative risk for the occurrence of CKD between different occupations in the US adult population. Materials and methods: This was a population-based survey study of 91,340 participants in the US, who completed the National Health Interview Survey, 2004 through 2008. The outcome variable, CKD, was defined as having weakening/failing kidneys in the past 12 months, as diagnosed by a physician. The predictor variable, occupation, was obtained using the census occupational codes, regrouped according to North American Industrial Classification System. Results: After controlling for age, gender, hypertension, and education, and with the category Life, Physical, and Social Science Occupations as a reference group, the likelihood of developing CKD was 4.3 times higher in respondents working in Building, Grounds Cleaning and Maintenance Occupations, 4.4 times higher in Healthcare Practitioners and Technical Occupations, 4.7 times higher in Transportation and Material Moving Occupations and in Computer and Mathematical Occupations, 4.8 times higher in Production Occupations, 5.3 times higher in Food Preparation and Serving Related Occupations, and 6.1 times higher in Healthcare Support Occupations and in Legal Occupations. Conclusion: This study identified occupation groups in US adult population with increased risk for CKD. Alleviation of workplace stress is suggested as a goal for behavioral intervention in high-risk occupations. Keywords: CKD, risk factors, occupations

  16. A review of the methods for monitoring roe deer European populations with particular reference to Italy

    Directory of Open Access Journals (Sweden)

    Alberto Meriggi

    2009-02-01

    Full Text Available Abstract Throughout the last century, deer populations have shown a remarkable increase both in North America and Europe. As a consequence, the estimate of roe deer density has become a matter of interest. We reviewed the available literature on the methods used for monitoring roe deer populations in Europe from 1950 to 2004, with the aim of detecting the trend of papers and distribution of census techniques by years, countries and habitat types. Particular attention was paid to the census and monitoring methods adopted in Italy and Tuscany, which is the region where the roe deer is more carefully managed. Published papers showed an increasing trend, as did the number of methods used and their complexity. France, Italy, UK and Spain were the countries with the richest literature and the largest variety of methods applied. Eleven census methods have been applied in woods - particularly line transects, pellet group counts, CMR and IKA - with only 6 in open country, mainly pellet group counts. In Europe vantage points are more commonly used for planning culling programs, whilst in Italy, and particularly in Tuscany, the drive census and spotlight counts are mainly used. Unfortunately, in Europe, harvesting programs are still too much based on hunter knowledge and traditions. However the countries where the management of roe deer hunting is of more recent tradition make an exception to this rule. In Italy and Tuscany the methods of monitoring roe deer populations should be improved towards less expensive and more accurate methods. Riassunto Revisione dei metodi di monitoraggio delle popolazioni di capriolo in Europa con particolare riferimento all'Italia Le popolazioni di Cervidi hanno avuto nell'ultimo secolo un notevole incremento sia in America settentrionale, sia in Europa. Di conseguenza la densità delle popolazioni di capriolo è diventata oggetto di interessi diversi e la sua stima

  17. A probabilistic method for testing and estimating selection differences between populations.

    Science.gov (United States)

    He, Yungang; Wang, Minxian; Huang, Xin; Li, Ran; Xu, Hongyang; Xu, Shuhua; Jin, Li

    2015-12-01

    Human populations around the world encounter various environmental challenges and, consequently, develop genetic adaptations to different selection forces. Identifying the differences in natural selection between populations is critical for understanding the roles of specific genetic variants in evolutionary adaptation. Although numerous methods have been developed to detect genetic loci under recent directional selection, a probabilistic solution for testing and quantifying selection differences between populations is lacking. Here we report the development of a probabilistic method for testing and estimating selection differences between populations. By use of a probabilistic model of genetic drift and selection, we showed that logarithm odds ratios of allele frequencies provide estimates of the differences in selection coefficients between populations. The estimates approximate a normal distribution, and variance can be estimated using genome-wide variants. This allows us to quantify differences in selection coefficients and to determine the confidence intervals of the estimate. Our work also revealed the link between genetic association testing and hypothesis testing of selection differences. It therefore supplies a solution for hypothesis testing of selection differences. This method was applied to a genome-wide data analysis of Han and Tibetan populations. The results confirmed that both the EPAS1 and EGLN1 genes are under statistically different selection in Han and Tibetan populations. We further estimated differences in the selection coefficients for genetic variants involved in melanin formation and determined their confidence intervals between continental population groups. Application of the method to empirical data demonstrated the outstanding capability of this novel approach for testing and quantifying differences in natural selection. © 2015 He et al.; Published by Cold Spring Harbor Laboratory Press.

  18. Population-based study of Hodgkin's lymphoma in Kuwait.

    Science.gov (United States)

    Alshemmari, S; Sajnani, K P; Refaat, S; Albassami, A

    2011-01-01

    Hodgkin lymphoma (HL) comprises about 25% of all malignant nodal lymphomas worldwide. Incidence of HL has been increasing in many countries around the world, in the western countries in particular. Cancer incidence variations in different ethnic groups in the same country can lead to some important information about the search of etiological factors. Some researchers found an association between ethnicity and increased risk of HL. In this study, we evaluated the epidemiologic and clinical characteristics of patients with HL and the HL subtypes in Kuwait who were diagnosed between 1998 and 2006 and we analyzed the changes in the incidence of HL over time based on age, sex, and ethnicity. The Kuwait Cancer Control Center is a tertiary referral hospital and the only cancer hospital in the entire state of Kuwait. We identified 293 patients who were newly diagnosed with HL by histopathology between January 1, 1998, and December 31, 2006, at the Kuwait Cancer Control Center. Incidence data were crossvalidated with the population-based Cancer Registry of Kuwait. Clinical data were obtained by reviewing the patients' medical records. The median age at diagnosis was 39 years (range, 10-85 years) for patients with cHL and 36 years (range, 14-51 years) for patients with NLPHL. The age-adjusted incidence rate was 2.1 cases (range, 1.2-2.9) per 100,000 people per year in the period between 1998 and 2006. NLPHL and cHL were predominant in men with a male to female ratio of 2:1. However, the mean annual percentage change in HL incidence among Kuwaiti patients and non-Kuwaiti patients per year showed unexplained higher percentage in females both Kuwaiti and non-Kuwaiti. cHL comprised 92.5% of all HL cases and NLPHL comprised 7.5%. Nodular sclerosis was the predominant histologic subtype of cHL (58.9%), whereas mixed cellularity was the second most frequent histologic subtype of cHL, (25.9%). Although the incidence of HL was slightly lower in Kuwait than the worldwide incidence; it

  19. Methods to improve genomic prediction and GWAS using combined Holstein populations

    DEFF Research Database (Denmark)

    Li, Xiujin

    The thesis focuses on methods to improve GWAS and genomic prediction using combined Holstein populations and investigations G by E interaction. The conclusions are: 1) Prediction reliabilities for Brazilian Holsteins can be increased by adding Nordic and Frensh genotyped bulls and a large G by E...... interaction exists between populations. 2) Combining data from Chinese and Danish Holstein populations increases the power of GWAS and detects new QTL regions for milk fatty acid traits. 3) The novel multi-trait Bayesian model efficiently estimates region-specific genomic variances, covariances...

  20. OCCUPATION AND EPICONDYLITIS: A POPULATION-BASED STUDY

    Science.gov (United States)

    Walker-Bone, Karen; Palmer, Keith T; Reading, Isabel C; Coggon, David; Cooper, Cyrus

    2012-01-01

    Objectives To explore the relationship between occupational exposures and lateral and medial epicondylitis and the effect of epicondylitis on sickness absence in a population sample of working aged adults. Methods This was a cross-sectional study of 9696 randomly selected adults aged 25-64 years involving a screening questionnaire and standardised physical examination. Age- and sex-specific prevalence rates of epicondylitis were estimated and associations with occupational risk factors explored. Results Among 6038 respondents, 636 (11%) reported elbow pain in the last week. 0.7% of those surveyed were diagnosed with lateral epicondylitis and 0.6% with medial epicondylitis. Lateral epicondylitis was associated with manual work (OR 4.0, 95% CI 1.9-8.4). In multivariate analyses, repetitive bending/straightening elbow > 1 hour day was independently associated with lateral (OR 2.5, 95% CI 1.2-5.5) and medial epicondylitis (OR 5.1, 95% CI 1.8-14.3). 5% of adults with epicondylitis took sickness absence because of their elbow symptoms in the past 12 months (median 29 days). Conclusions Repetitive exposure to bending/straightening the elbow was a significant risk factor for medial and lateral epicondylitis. Epicondylitis is associated with prolonged sickness absence in 5% of affected working-aged adults. PMID:22019808

  1. Comparative study of different methods used in assessment of population exposure to external environmental radiation

    International Nuclear Information System (INIS)

    Niewiadomski, T.

    1979-08-01

    Doses received by individuals and population from terrestial radiation sources were estimated using three approaches, 1) measurements of dose rates, 2) calculations on the basis of spectrometric analysis of the soil or local radiation field and 3) integrating dosimeters. The 1st approach was carried out by means of pressurised ionization chambers, scintillation counters or GM counters properly calibrated, and also by supplying individuals with dosimetric or radiometric instruments. The data for calculation assessment was based on measurements of dose rates both outdoors and indoors and often taken from spectrometric analysis of natural radionuclide. Several equations and calculation factors have been derived and computer programs developed for calculating the concentration of radionuclides in question and for estimating dose rates in π or 2π geometries. Integrating measurements were carried out using TL dosimeters. To assess the reliability of the methods, comparative measurements were carried out at statistically representative number of locations using a wide choice of techniques. The detailed methods used and the equipment are described in the research programme as well as the results of the measurements. The most reliable results are these obtained when measurements are carried out over a long period of time, e.g. one year

  2. Feasible Initial Population with Genetic Diversity for a Population-Based Algorithm Applied to the Vehicle Routing Problem with Time Windows

    Directory of Open Access Journals (Sweden)

    Marco Antonio Cruz-Chávez

    2016-01-01

    Full Text Available A stochastic algorithm for obtaining feasible initial populations to the Vehicle Routing Problem with Time Windows is presented. The theoretical formulation for the Vehicle Routing Problem with Time Windows is explained. The proposed method is primarily divided into a clustering algorithm and a two-phase algorithm. The first step is the application of a modified k-means clustering algorithm which is proposed in this paper. The two-phase algorithm evaluates a partial solution to transform it into a feasible individual. The two-phase algorithm consists of a hybridization of four kinds of insertions which interact randomly to obtain feasible individuals. It has been proven that different kinds of insertions impact the diversity among individuals in initial populations, which is crucial for population-based algorithm behavior. A modification to the Hamming distance method is applied to the populations generated for the Vehicle Routing Problem with Time Windows to evaluate their diversity. Experimental tests were performed based on the Solomon benchmarking. Experimental results show that the proposed method facilitates generation of highly diverse populations, which vary according to the type and distribution of the instances.

  3. Fetal size monitoring and birth-weight prediction: a new population-based approach.

    Science.gov (United States)

    Gjessing, H K; Grøttum, P; Økland, I; Eik-Nes, S H

    2017-04-01

    To develop a complete, population-based system for ultrasound-based fetal size monitoring and birth-weight prediction for use in the second and third trimesters of pregnancy. Using 31 516 ultrasound examinations from a population-based Norwegian clinical database, we constructed fetal size charts for biparietal diameter, femur length and abdominal circumference from 24 to 42 weeks' gestation. A reference curve of median birth weight for gestational age was estimated using 45 037 birth weights. We determined how individual deviations from the expected ultrasound measures predicted individual percentage deviations from expected birth weight. The predictive quality was assessed by explained variance of birth weight and receiver-operating characteristics curves for prediction of small-for-gestational age. A curve for intrauterine estimated fetal weight was constructed. Charts were smoothed using the gamlss non-linear regression method. The population-based approach, using bias-free ultrasound gestational age, produces stable estimates of size-for-age and weight-for-age curves in the range 24-42 weeks' gestation. There is a close correspondence between percentage deviations and percentiles of birth weight by gestational age, making it easy to convert between the two. The variance of birth weight that can be 'explained' by ultrasound increases from 8% at 20 weeks up to 67% around term. Intrauterine estimated fetal weight is 0-106 g higher than median birth weight in the preterm period. The new population-based birth-weight prediction model provides a simple summary measure, the 'percentage birth-weight deviation', to be used for fetal size monitoring throughout the third trimester. Predictive quality of the model can be measured directly from the population data. The model computes both median observed birth weight and intrauterine estimated fetal weight. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2016 ISUOG. Published by John

  4. Bus Based Synchronization Method for CHIPPER Based NoC

    Directory of Open Access Journals (Sweden)

    D. Muralidharan

    2016-01-01

    Full Text Available Network on Chip (NoC reduces the communication delay of System on Chip (SoC. The main limitation of NoC is power consumption and area overhead. Bufferless NoC reduces the area complexity and power consumption by eliminating buffers in the traditional routers. The bufferless NoC design should include live lock freeness since they use hot potato routing. This increases the complexity of bufferless NoC design. Among the available propositions to reduce this complexity, CHIPPER based bufferless NoC is considered as one of the best options. Live lock freeness is provided in CHIPPER through golden epoch and golden packet. All routers follow some synchronization method to identify a golden packet. Clock based method is intuitively followed for synchronization in CHIPPER based NoCs. It is shown in this work that the worst-case latency of packets is unbearably high when the above synchronization is followed. To alleviate this problem, broadcast bus NoC (BBus NoC approach is proposed in this work. The proposed method decreases the worst-case latency of packets by increasing the golden epoch rate of CHIPPER.

  5. Comparison between ARIMA and DES Methods of Forecasting Population for Housing Demand in Johor

    Directory of Open Access Journals (Sweden)

    Alias Ahmad Rizal

    2016-01-01

    Full Text Available Forecasting accuracy is a primary criterion in selecting appropriate method of prediction. Even though there are various methods of forecasting however not all of these methods are able to predict with good accuracy. This paper presents an evaluation of two methods of population forecasting for housing demand. These methods are Autoregressive Integrated Moving Average (ARIMA and Double Exponential Smoothing (DES. Both of the methods are principally adopting univariate time series analysis which uses past and present data for forecasting. Secondary data obtained from Department of Statistics, Malaysia was used to forecast population for housing demand in Johor. Forecasting processes had generated 14 models to each of the methods and these models where evaluated using Mean Absolute Percentage Error (MAPE. It was found that 14 of Double Exponential Smoothing models and also 14 of ARIMA models had resulted to 1.674% and 5.524% of average MAPE values respectively. Hence, the Double Exponential Smoothing method outperformed the ARIMA method by reducing 4.00 % in forecasting model population for Johor state. These findings help researchers and government agency in selecting appropriate forecasting model for housing demand.

  6. Urban Optimum Population Size and Development Pattern Based on Ecological Footprint Model: Case of Zhoushan, China

    Directory of Open Access Journals (Sweden)

    Yuan LU

    2016-09-01

    Full Text Available The agglomeration of population in the city can reflect the prosperity in the economy, society and culture. However, it has also brought a series of problems like environmental pollution, traffic congestion, housing shortage and jobs crisis. The results can be shown as the failure of urban comprehensive function, the decline of city benefits, and the contradiction between socioeconomic circumstance and ecosystem. Therefore, a reasonable population capacity, which is influenced by ecological resources, urban environment, geographical elements, social and economic factors, etc., is objectively needed. How to deal with the relationship between the utilization of natural capital and development of the city is extremely essential. This paper takes Zhoushan Island as an example, which is the fourth largest island off the coast of China. Firstly, the interactively influencing factors of urban optimal population are illustrated. And method is chosen to study the optimal population size. Secondly, based on the model of ecological footprint (EP, the paper calculates and analyzes the ecological footprint and ecological capacity of the Zhoushan Island, in order to explore the optimal population size of the city. Thirdly, analysis and evaluation of the resources and urban environment carrying capacity is made. Finally, the solution of the existing population problems and the suggestion for the future development pattern of the city are proposed in the urban eco-planning of Zhoushan Island. The main strategies can be summarized in two aspects: one is to reduce the ecological footprint, the other is to increase the ecological supply. The conclusion is that the current population of Zhoushan Island is far beyond the optimum population size calculated by the ecological footprint model. Therefore, sustainable development should be the guidance for urban planning in Zhoushan Island, and a low-carbon development pattern for the city is advocated.

  7. METHODICAL BASES OF MANAGEMENT OF INSURANCE PORTFOLIO

    Directory of Open Access Journals (Sweden)

    Serdechna Yulia

    2018-01-01

    Full Text Available Introduction. Despite the considerable arsenal of developments in the issues of assessing the management of the insurance portfolio remains unresolved. In order to detail, specify and further systematize the indicators for the indicated evaluation, the publications of scientists are analyzed. The purpose of the study is to analyze existing methods by which it is possible to formulate and manage the insurance portfolio in order to achieve its balance, which will contribute to ensuring the financial reliability of the insurance company. Results. The description of the essence of the concept of “management of insurance portfolio”, as the application of actuarial methods and techniques to the combination of various insurance risks offered for insurance or are already part of the insurance portfolio, allowing to adjust the size and structure of the portfolio in order to ensure its financial stability, achievement the maximum level of income of an insurance organization, preservation of the value of its equity and financial security of insurance liabilities. It is determined that the main methods by which the insurer’s insurance portfolio can be formed and managed is the selection of risks; reinsurance operations that ensure diversification of risks; formation and placement of insurance reserves, which form the financial basis of insurance activities. The method of managing an insurance portfolio, which can be both active and passive, is considered. Conclusions. It is determined that the insurance portfolio is the basis on which all the activities of the insurer are based and which determines its financial stability. The combination of methods and technologies applied to the insurance portfolio is a management method that can be both active and passive and has a number of specific methods through which the insurer’s insurance portfolio can be formed and managed. It is substantiated that each insurance company aims to form an efficient and

  8. Cut Based Method for Comparing Complex Networks.

    Science.gov (United States)

    Liu, Qun; Dong, Zhishan; Wang, En

    2018-03-23

    Revealing the underlying similarity of various complex networks has become both a popular and interdisciplinary topic, with a plethora of relevant application domains. The essence of the similarity here is that network features of the same network type are highly similar, while the features of different kinds of networks present low similarity. In this paper, we introduce and explore a new method for comparing various complex networks based on the cut distance. We show correspondence between the cut distance and the similarity of two networks. This correspondence allows us to consider a broad range of complex networks and explicitly compare various networks with high accuracy. Various machine learning technologies such as genetic algorithms, nearest neighbor classification, and model selection are employed during the comparison process. Our cut method is shown to be suited for comparisons of undirected networks and directed networks, as well as weighted networks. In the model selection process, the results demonstrate that our approach outperforms other state-of-the-art methods with respect to accuracy.

  9. Economic costs of social phobia: a population-based study.

    Science.gov (United States)

    Acarturk, C; Smit, Filip; de Graaf, R; van Straten, A; Ten Have, M; Cuijpers, P

    2009-06-01

    Information about the economic costs of social phobia is scant. In this study, we examine the economic costs of social phobia and subthreshold social phobia. Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) which is a population-based prospective study (n=4,789). Costs related to health service uptake, patients' out-of-pocket expenses, and costs arising from production losses were calculated for the reference year 2003. The costs for people with social phobia were compared with the costs for people with no mental disorder. The annual per capita total costs of social phobia were euro 11,952 (95% CI=7,891-16,013) which is significantly higher than the total costs for people with no mental disorder, euro 2957 (95% CI=2690-3224). When adjusting for mental and somatic co-morbidity, the costs decreased to euro 6,100 (95% CI=2681-9519), or 136 million euro per year per 1 million inhabitants, which was still significantly higher than the costs for people with no mental disorder. The costs of subthreshold social phobia were also significantly higher than the costs for people without any mental disorder, at euro 4,687 (95% CI=2557-6816). The costs presented here are conservative lower estimates because we only included costs related to mental health services. The economic costs associated with social phobia are substantial, and those of subthreshold social phobia approach those of the full-blown disorder.

  10. Population-Based Study of Trachoma in Guatemala.

    Science.gov (United States)

    Silva, Juan Carlos; Diaz, Marco Antonio; Maul, Eugenio; Munoz, Beatriz E; West, Sheila K

    2015-01-01

    A prevalence survey for active trachoma in children aged under 10 years and trichiasis in women aged 40 years and older was carried out in four districts in the Sololá region in Guatemala, which is suspected of still having a trachoma problem. Population-based surveys were undertaken in three districts, within 15 randomly selected communities in each district. In addition, in a fourth district that borders the third district chosen, we surveyed the small northern sub-district, by randomly selecting three communities in each community, 100 children aged under 10 years were randomly selected, and all females over 40 years. Five survey teams were trained and standardized. Trachoma was graded using the World Health Organization simplified grading scheme and ocular swabs were taken in cases of clinical follicular or inflammatory trachoma. Prevalence estimates were calculated at district and sub-district level. Trachoma rates at district level varied from 0-5.1%. There were only two sub-districts where active trachoma approached 10% (Nahualá Costa, 8.1%, and Santa Catarina Costa, 7.3%). Trichiasis rates in females aged 40 years and older varied from 0-3%. Trachoma was likely a problem in the past. Trachoma is disappearing in the Sololá region in Guatemala. Health leadership may consider further mapping of villages around the areas with an especially high rate of trachoma and infection, and instituting trichiasis surgery and active trachoma intervention where needed.

  11. Calcium intake by adolescents: a population-based health survey.

    Science.gov (United States)

    de Assumpção, Daniela; Dias, Marcia Regina Messaggi Gomes; de Azevedo Barros, Marilisa Berti; Fisberg, Regina Mara; de Azevedo Barros Filho, Antonio

    2016-01-01

    To analyze calcium intake in adolescents according to sociodemographic variables, health-related behaviors, morbidities, and body mass index. This was a cross-sectional population-based study, with a two-stage cluster sampling that used data from a survey conducted in Campinas, São Paulo, Brazil, between 2008 and 2009. Food intake was assessed using a 24-hour dietary recall. The study included 913 adolescents aged 10-19 years. Average nutrient intake was significantly lower in the segment with lower education of the head of the family and lower per capita family income, in individuals from other cities or states, those who consumed fruit less than four times a week, those who did not drink milk daily, those who were smokers, and those who reported the occurrence of headaches and dizziness. Higher mean calcium intake was found in individuals that slept less than seven hours a day. The prevalence of calcium intake below the recommendation was 88.6% (95% CI: 85.4-91.2). The results alert to an insufficient calcium intake and suggest that certain subgroups of adolescents need specific strategies to increase the intake of this nutrient. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  12. [Population-based study of diabetic retinopathy in Wolfsburg].

    Science.gov (United States)

    Hesse, L; Grüsser, M; Hoffstadt, K; Jörgens, V; Hartmann, P; Kroll, P

    2001-11-01

    Since November 1997 the complete documentation of an ophthalmological examination of diabetics has been annually subsidized by the Volkswagen Corporation Health Maintenance Organization (VW-HMO). The results of an annual ophthalmological examination were recorded in a standardised history sheet developed by the Initiative Group for Early Detection of Diabetic Eye Diseases. These data included visual acuity, intraocular pressure, lens status and a description of fundus abnormalities. Within 26 months ophthalmological examinations of 2,801 patients were completed which represented 4.5% of all VW-HMO insured patients. On average, patients suffered from diabetes for 9.6 years (SD +/- 8.3), artificial intraocular lenses were present in 357 eyes (6.4%) and 1,216 eyes (12.0%) were diagnosed with cataract or posterior capsule opacification impairing visual acuity. Out of 263 patients younger than 40 years old, 18.8% had a mild or moderate and 3.3% a severe non-proliferative diabetic retinopathy (NPDR). A proliferative diabetic retinopathy (PDR) was found in 2.2% of the younger patients. Of 2,228 patients aged 40 years and older, 11.9% had a mild or moderate and 2.6% a severe NPDR. In 0.9% of this group PDR was diagnosed. An annual ophthalmological screening based on a survey sheet of the Initiative Group was successfully introduced. For the first time a population-based evaluation on the prevalence of diabetic retinopathy was carried out for inhabitants of a German city. The prevalence of PDR was found to be lower than previously published in comparable studied.

  13. A principled dimension-reduction method for the population density approach to modeling networks of neurons with synaptic dynamics.

    Science.gov (United States)

    Ly, Cheng

    2013-10-01

    The population density approach to neural network modeling has been utilized in a variety of contexts. The idea is to group many similar noisy neurons into populations and track the probability density function for each population that encompasses the proportion of neurons with a particular state rather than simulating individual neurons (i.e., Monte Carlo). It is commonly used for both analytic insight and as a time-saving computational tool. The main shortcoming of this method is that when realistic attributes are incorporated in the underlying neuron model, the dimension of the probability density function increases, leading to intractable equations or, at best, computationally intensive simulations. Thus, developing principled dimension-reduction methods is essential for the robustness of these powerful methods. As a more pragmatic tool, it would be of great value for the larger theoretical neuroscience community. For exposition of this method, we consider a single uncoupled population of leaky integrate-and-fire neurons receiving external excitatory synaptic input only. We present a dimension-reduction method that reduces a two-dimensional partial differential-integral equation to a computationally efficient one-dimensional system and gives qualitatively accurate results in both the steady-state and nonequilibrium regimes. The method, termed modified mean-field method, is based entirely on the governing equations and not on any auxiliary variables or parameters, and it does not require fine-tuning. The principles of the modified mean-field method have potential applicability to more realistic (i.e., higher-dimensional) neural networks.

  14. Estimation of effectiveness of three methods of feral cat population control by use of a simulation model.

    Science.gov (United States)

    McCarthy, Robert J; Levine, Stephen H; Reed, J Michael

    2013-08-15

    To predict effectiveness of 3 interventional methods of population control for feral cat colonies. Population model. Estimates of vital data for feral cats. Data were gathered from the literature regarding the demography and mating behavior of feral cats. An individual-based stochastic simulation model was developed to evaluate the effectiveness of trap-neuter-release (TNR), lethal control, and trap-vasectomy-hysterectomy-release (TVHR) in decreasing the size of feral cat populations. TVHR outperformed both TNR and lethal control at all annual capture probabilities between 10% and 90%. Unless > 57% of cats were captured and neutered annually by TNR or removed by lethal control, there was minimal effect on population size. In contrast, with an annual capture rate of ≥ 35%, TVHR caused population size to decrease. An annual capture rate of 57% eliminated the modeled population in 4,000 days by use of TVHR, whereas > 82% was required for both TNR and lethal control. When the effect of fraction of adult cats neutered on kitten and young juvenile survival rate was included in the analysis, TNR performed progressively worse and could be counterproductive, such that population size increased, compared with no intervention at all. TVHR should be preferred over TNR for management of feral cats if decrease in population size is the goal. This model allowed for many factors related to the trapping program and cats to be varied and should be useful for determining the financial and person-effort commitments required to have a desired effect on a given feral cat population.

  15. Incidence of hand eczema in a population-based twin cohort

    DEFF Research Database (Denmark)

    Lerbaek, A; Kyvik, Kirsten Ohm; Ravn, H

    2007-01-01

    BACKGROUND: Population-based studies on the incidence of hand eczema are sparse. OBJECTIVES: The aim of this prospective follow-up study was to determine the incidence rate of hand eczema in a population-based twin cohort. Secondly, the role of genetic factors and other potential risk factors...... for hand eczema was investigated. METHODS: A questionnaire on self-reported hand eczema was answered by 5610 and 4128 twin individuals in 1996 and 2005, respectively. Data were analysed in a Poisson regression analysis. RESULTS: The crude incidence rate was 8.8 cases per 1000 person-years (95% confidence...... with an increased risk, whereas no association with age, sex, smoking or alcohol was found...

  16. Population-Based Assessment of Exposure to Risk Behaviors in Motion Pictures.

    Science.gov (United States)

    Sargent, James D; Worth, Keilah A; Beach, Michael; Gerrard, Meg; Heatherton, Todd F

    2008-01-01

    The aim of most population-based studies of media is to relate a specific exposure to an outcome of interest. A research program has been developed that evaluates exposure to different components of movies in an attempt of assess the association of such exposure with the adoption of substance use during adolescence. To assess exposure to movie substance use, one must measure both viewing time and content. In developing the exposure measure, the study team was interested in circumventing a common problem in exposure measurement, where measures often conflate exposure to media with attention to media. Our aim in this paper is to present a validated measure of exposure to entertainment media, the Beach method, which combines recognition of a movie title with content analysis of the movie for substance use, to generate population based measures of exposure to substance use in this form of entertainment.

  17. Familial risk of epilepsy: a population-based study

    Science.gov (United States)

    Peljto, Anna L.; Barker-Cummings, Christie; Vasoli, Vincent M.; Leibson, Cynthia L.; Hauser, W. Allen; Buchhalter, Jeffrey R.

    2014-01-01

    Almost all previous studies of familial risk of epilepsy have had potentially serious methodological limitations. Our goal was to address these limitations and provide more rigorous estimates of familial risk in a population-based study. We used the unique resources of the Rochester Epidemiology Project to identify all 660 Rochester, Minnesota residents born in 1920 or later with incidence of epilepsy from 1935–94 (probands) and their 2439 first-degree relatives who resided in Olmsted County. We assessed incidence of epilepsy in relatives by comprehensive review of the relatives’ medical records, and estimated age-specific cumulative incidence and standardized incidence ratios for epilepsy in relatives compared with the general population, according to proband and relative characteristics. Among relatives of all probands, cumulative incidence of epilepsy to age 40 was 4.7%, and risk was increased 3.3-fold (95% confidence interval 2.75–5.99) compared with population incidence. Risk was increased to the greatest extent in relatives of probands with idiopathic generalized epilepsies (standardized incidence ratio 6.0) and epilepsies associated with intellectual or motor disability presumed present from birth, which we denoted ‘prenatal/developmental cause’ (standardized incidence ratio 4.3). Among relatives of probands with epilepsy without identified cause (including epilepsies classified as ‘idiopathic’ or ‘unknown cause’), risk was significantly increased for epilepsy of prenatal/developmental cause (standardized incidence ratio 4.1). Similarly, among relatives of probands with prenatal/developmental cause, risk was significantly increased for epilepsies without identified cause (standardized incidence ratio 3.8). In relatives of probands with generalized epilepsy, standardized incidence ratios were 8.3 (95% confidence interval 2.93–15.31) for generalized epilepsy and 2.5 (95% confidence interval 0.92–4.00) for focal epilepsy. In relatives of

  18. A method for estimating abundance of mobile populations using telemetry and counts of unmarked animals

    Science.gov (United States)

    Clement, Matthew; O'Keefe, Joy M; Walters, Brianne

    2015-01-01

    While numerous methods exist for estimating abundance when detection is imperfect, these methods may not be appropriate due to logistical difficulties or unrealistic assumptions. In particular, if highly mobile taxa are frequently absent from survey locations, methods that estimate a probability of detection conditional on presence will generate biased abundance estimates. Here, we propose a new estimator for estimating abundance of mobile populations using telemetry and counts of unmarked animals. The estimator assumes that the target population conforms to a fission-fusion grouping pattern, in which the population is divided into groups that frequently change in size and composition. If assumptions are met, it is not necessary to locate all groups in the population to estimate abundance. We derive an estimator, perform a simulation study, conduct a power analysis, and apply the method to field data. The simulation study confirmed that our estimator is asymptotically unbiased with low bias, narrow confidence intervals, and good coverage, given a modest survey effort. The power analysis provided initial guidance on survey effort. When applied to small data sets obtained by radio-tracking Indiana bats, abundance estimates were reasonable, although imprecise. The proposed method has the potential to improve abundance estimates for mobile species that have a fission-fusion social structure, such as Indiana bats, because it does not condition detection on presence at survey locations and because it avoids certain restrictive assumptions.

  19. The association between systemic inflammatory cellular levels and lung function: a population-based study.

    Directory of Open Access Journals (Sweden)

    Tricia McKeever

    Full Text Available BACKGROUND: Lower lung function is associated with an elevated systemic white cell count in men. However, these observations have not been demonstrated in a representative population that includes females and may be susceptible to confounding by recent airway infections or recent cigarette smoking. We tested the hypothesis that lung function is inversely associated with systemic white cell count in a population-based study. METHODS: The study population consisted adults aged 17-90+ years who participated in the Third National Health and Nutrition Examination Survey who did not report a recent cough, cold or acute illness in a non-smoking and smoking population. RESULTS: In non-smoking adults with the highest quintile of the total white cell count had a FEV(1 125.3 ml lower than those in the lowest quintile (95% confidence interval CI: -163.1 to -87.5. Adults with the highest quintile of the total white cell count had a FVC 151.1 ml lower than those in the lowest quintile (95% confidence interval CI: -195.0 to -107.2. Similar associations were observed for granulocytes, mononuclear cells and lymphocytes. In current smokers, similar smaller associations observed for total white cell count, granulocytes and mononuclear cells. CONCLUSIONS: Systemic cellular inflammation levels are inversely associated with lung function in a population of both non-smokers and smokers without acute illnesses. This may contribute to the increased mortality observed in individuals with a higher baseline white cell count.

  20. Energy drinks consumption in Erbil city: A population based study

    Directory of Open Access Journals (Sweden)

    Yassin A. Asaad

    2017-08-01

    Full Text Available Background and objective: Energy drinks have become increasingly prevalent among young adults and adolescents in recent years, particularly young students and athletes who see the consumption of energy drinks as an easy and quick way to boost academic and athletic performance. This study was conducted to determine the prevalence of consumption of energy drinks in a sample of adolescent and adults in Erbil city as well as perceived benefits and its health hazards. Methods: A convenience sample of 600 individuals from different sectors and social groups of Erbil city was selected. Data was obtained through direct interview. The data was managed through SPSS program version 18, using appropriate statistical tests. Results: The prevalence of energy drinks consumption among the study population was 42.7%, especially adolescents and young adults (those ≤ 25 years and was more common among males than females (55.7% and 29.8%, respectively. The main reasons for its consumption were related to getting energy and improving the mood and performance (66.0% and 30.4%, respectively. 62.7% of participants think that it is harmful and could have adverse effects such as heartbeat irregularity and blood pressure swinging, addiction, and osteoporosis (46.2%, 33.7% and 13.2%, respectively. Televisions were the major source of advertisement (71.45. A significant statistical association had been found between the age, gender and educational status of the participants and consuming energy drinks (P = 0.001, 0.001 and 0.002, respectively. Conclusion: Energy drinks consumption found to be highly prevalent in adolescents and young adults in Erbil city, which calls for review and regulating the sale of these drinks including adolescents' education, raising community’s awareness, banning selling it in public places and increasing taxes.

  1. A spatial analysis of patterns of growth and concentration of population based on homogeneous population censuses: Spain (1877-2001

    Directory of Open Access Journals (Sweden)

    Xavier Franch Auladell

    2013-01-01

    Full Text Available This work constitutes a contribution to the analysis of long term patterns of population concentration applied to the case of Spain. The proposed methodology is based on the homogenisation of both data and administrative units which takes the municipal structure of the 2001 census as its base reference. This work seeks to show how applying spatial analysis techniques to this type of homogeneous data series allows us to make more detailed studies of population patterns within a given territory. The most important conclusions that we reached was that, in Spain, sustained population growth has followed a spatial pattern that has become increasingly consolidated over time. The tendencies observed have produced an uneven distribution of population within the national territory marked by the existence of a series of well-defined, and often very localised, areas that spread beyond the limits of the official administrative boundaries.

  2. Application of DNA-based methods in forensic entomology.

    Science.gov (United States)

    Wells, Jeffrey D; Stevens, Jamie R

    2008-01-01

    A forensic entomological investigation can benefit from a variety of widely practiced molecular genotyping methods. The most commonly used is DNA-based specimen identification. Other applications include the identification of insect gut contents and the characterization of the population genetic structure of a forensically important insect species. The proper application of these procedures demands that the analyst be technically expert. However, one must also be aware of the extensive list of standards and expectations that many legal systems have developed for forensic DNA analysis. We summarize the DNA techniques that are currently used in, or have been proposed for, forensic entomology and review established genetic analyses from other scientific fields that address questions similar to those in forensic entomology. We describe how accepted standards for forensic DNA practice and method validation are likely to apply to insect evidence used in a death or other forensic entomological investigation.

  3. Progression to impaired glucose regulation and diabetes in the population-based Inter99 study

    DEFF Research Database (Denmark)

    Engberg, Susanne; Vistisen, Dorte; Lau, Cathrine

    2009-01-01

    Objective: To estimate the progression rates to impaired glucose regulation (impaired fasting glucose or impaired glucose tolerance) and diabetes in the Danish population-based Inter99 study and in a high-risk subpopulation, separately. Research Design and Methods: From a population-based primary...... glucose regulation using the current World Health Organization classification criteria were calculated for the first time in a large European population-based study. The progression rates to diabetes show the same pattern as seen in the few similar European studies....... prevention study, the Inter99 study, 4,615 individuals without diabetes at baseline and with relevant follow-up data were divided into a low- and a high-risk group based on a risk estimate of ischemic heart disease or the presence of risk factors (smoking, hypertension, hypercholesterolemia, obesity...... estimated directly from baseline to 5-year follow-up for all the participants, and from baseline through 1- and 3-, to 5-year follow-up for the high-risk individuals, separately. Results: In the combined low- and high-risk group, 2.1 per 100 person-years progressed from normal glucose tolerance to impaired...

  4. Stages of development and injury patterns in the early years: a population-based analysis

    Directory of Open Access Journals (Sweden)

    Simpson Kelly

    2006-07-01

    Full Text Available Abstract Background In Canada, there are many formal public health programs under development that aim to prevent injuries in the early years (e.g. 0–6. There are paradoxically no population-based studies that have examined patterns of injury by developmental stage among these young children. This represents a gap in the Canadian biomedical literature. The current population-based analysis explores external causes and consequences of injuries experienced by young children who present to the emergency department for assessment and treatment. This provides objective evidence about prevention priorities to be considered in anticipatory counseling and public health planning. Methods Four complete years of data (1999–2002; n = 5876 cases were reviewed from the Kingston sites of the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP, an ongoing injury surveillance initiative. Epidemiological analyses were used to characterize injury patterns within and across age groups (0–6 years that corresponded to normative developmental stages. Results The average annual rate of emergency department-attended childhood injury was 107 per 1000 (95% CI 91–123, with boys experiencing higher annual rates of injury than girls (122 vs. 91 per 1000; p Conclusion This population-based injury surveillance analysis provides a strong evidence-base to inform and enhance anticipatory counseling and other public health efforts aimed at the prevention of childhood injury during the early years.

  5. A flocking based method for brain tractography.

    Science.gov (United States)

    Aranda, Ramon; Rivera, Mariano; Ramirez-Manzanares, Alonso

    2014-04-01

    We propose a new method to estimate axonal fiber pathways from Multiple Intra-Voxel Diffusion Orientations. Our method uses the multiple local orientation information for leading stochastic walks of particles. These stochastic particles are modeled with mass and thus they are subject to gravitational and inertial forces. As result, we obtain smooth, filtered and compact trajectory bundles. This gravitational interaction can be seen as a flocking behavior among particles that promotes better and robust axon fiber estimations because they use collective information to move. However, the stochastic walks may generate paths with low support (outliers), generally associated to incorrect brain connections. In order to eliminate the outlier pathways, we propose a filtering procedure based on principal component analysis and spectral clustering. The performance of the proposal is evaluated on Multiple Intra-Voxel Diffusion Orientations from two realistic numeric diffusion phantoms and a physical diffusion phantom. Additionally, we qualitatively demonstrate the performance on in vivo human brain data. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Forced Ignition Study Based On Wavelet Method

    Science.gov (United States)

    Martelli, E.; Valorani, M.; Paolucci, S.; Zikoski, Z.

    2011-05-01

    The control of ignition in a rocket engine is a critical problem for combustion chamber design. Therefore it is essential to fully understand the mechanism of ignition during its earliest stages. In this paper the characteristics of flame kernel formation and initial propagation in a hydrogen-argon-oxygen mixing layer are studied using 2D direct numerical simulations with detailed chemistry and transport properties. The flame kernel is initiated by adding an energy deposition source term in the energy equation. The effect of unsteady strain rate is studied by imposing a 2D turbulence velocity field, which is initialized by means of a synthetic field. An adaptive wavelet method, based on interpolating wavelets is used in this study to solve the compressible reactive Navier- Stokes equations. This method provides an alternative means to refine the computational grid points according to local demands of the physical solution. The present simulations show that in the very early instants the kernel perturbed by the turbulent field is characterized by an increased burning area and a slightly increased rad- ical formation. In addition, the calculations show that the wavelet technique yields a significant reduction in the number of degrees of freedom necessary to achieve a pre- scribed solution accuracy.

  7. An econometric method for estimating population parameters from non-random samples: An application to clinical case finding.

    Science.gov (United States)

    Burger, Rulof P; McLaren, Zoë M

    2017-09-01

    The problem of sample selection complicates the process of drawing inference about populations. Selective sampling arises in many real world situations when agents such as doctors and customs officials search for targets with high values of a characteristic. We propose a new method for estimating population characteristics from these types of selected samples. We develop a model that captures key features of the agent's sampling decision. We use a generalized method of moments with instrumental variables and maximum likelihood to estimate the population prevalence of the characteristic of interest and the agents' accuracy in identifying targets. We apply this method to tuberculosis (TB), which is the leading infectious disease cause of death worldwide. We use a national database of TB test data from South Africa to examine testing for multidrug resistant TB (MDR-TB). Approximately one quarter of MDR-TB cases was undiagnosed between 2004 and 2010. The official estimate of 2.5% is therefore too low, and MDR-TB prevalence is as high as 3.5%. Signal-to-noise ratios are estimated to be between 0.5 and 1. Our approach is widely applicable because of the availability of routinely collected data and abundance of potential instruments. Using routinely collected data to monitor population prevalence can guide evidence-based policy making. Copyright © 2017 John Wiley & Sons, Ltd.

  8. On estimation of time-dependent attributable fraction from population-based case-control studies.

    Science.gov (United States)

    Zhao, Wei; Chen, Ying Qing; Hsu, Li

    2017-09-01

    Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.

  9. Sexuality after a cancer diagnosis: A population-based study.

    Science.gov (United States)

    Jackson, Sarah E; Wardle, Jane; Steptoe, Andrew; Fisher, Abigail

    2016-12-15

    This study explored differences in sexual activity, function, and concerns between cancer survivors and cancer-free controls in a population-based study. The data were from 2982 men and 3708 women who were 50 years old or older and were participating in the English Longitudinal Study of Ageing. Sexual well-being was assessed with the Sexual Relationships and Activities Questionnaire, and cancer diagnoses were self-reported. There were no differences between cancer survivors and controls in levels of sexual activity (76.0% vs 78.5% for men and 58.2% vs 55.5% for women) or sexual function. Men and women with cancer diagnoses were more dissatisfied with their sex lives than controls (age-adjusted percentages: 30.9% vs 19.8% for men [P = .023] and 18.2% vs 11.8% for women [P = .034]), and women with cancer were more concerned about levels of sexual desire (10.2% vs 7.1%; P = .006). Women diagnosed sexual desire (14.8% vs 7.1%; P = .007) and orgasmic experience (17.6% vs 7.1%; P = .042) than controls, but there were no differences in men. Self-reports of sexual activity and functioning in older people with cancer are broadly comparable to age-matched, cancer-free controls. There is a need to identify the causes of sexual dissatisfaction among long-term cancer survivors despite apparently normal levels of sexual activity and function for their age. The development of interventions addressing low sexual desire and problems with sexual functioning in women is also important and may be particularly relevant for cancer survivors after treatment. Cancer 2016;122:3883-3891. © 2016 American Cancer Society. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

  10. Falls and Depression in Men: A Population-Based Study.

    Science.gov (United States)

    Stuart, Amanda L; Pasco, Julie A; Jacka, Felice N; Berk, Michael; Williams, Lana J

    2018-01-01

    The link between falls and depression has been researched in the elderly; however, little information is available on this association in younger adults, particularly men. This study sought to investigate the link between major depressive disorder (MDD) and falls in a population-based sample of 952 men (24-97 years). MDD was diagnosed utilizing the Structured Clinical Interview for DSM-IV-TR Research Version, Non-Patient edition, and categorized as 12-month/past/never. Body mass index and gait were measured; falls, smoking status, psychotropic medication use, and alcohol intake were self-reported as part of the Geelong Osteoporosis Study 5-year follow-up assessment. Thirty-four (3.6%) men met criteria for 12-month MDD, and 110 (11.6%) for past MDD. Of the 952 men, 175 (18.4%) reported falling at least once during the past 12 months. Fallers were older (66 [interquartile range: 48-79] vs. 59 [45-72] years, p = .001) and more likely to have uneven gait ( n = 16, 10% vs. n = 31, 4%, p = .003) than nonfallers. Participants with 12-month MDD had more than twice the odds of falling (age-adjusted odds ratio: 2.22, 95% confidence interval [1.03, 4.80]). The odds of falling were not associated with past depression ( p = .4). Further adjustments for psychotropic drug use, gait, body mass index, smoking status, blood pressure, and alcohol did not explain these associations. Given the 2.2-fold greater likelihood of falling associated with depression was not explained by age or psychotropic drug use, further research is warranted.

  11. Predictors of fibromyalgia: a population-based twin cohort study.

    Science.gov (United States)

    Markkula, Ritva A; Kalso, Eija A; Kaprio, Jaakko A

    2016-01-15

    Fibromyalgia (FM) is a pain syndrome, the mechanisms and predictors of which are still unclear. We have earlier validated a set of FM-symptom questions for detecting possible FM in an epidemiological survey and thereby identified a cluster with "possible FM". This study explores prospectively predictors for membership of that FM-symptom cluster. A population-based sample of 8343 subjects of the older Finnish Twin Cohort replied to health questionnaires in 1975, 1981, and 1990. Their answers to the set of FM-symptom questions in 1990 classified them in three latent classes (LC): LC1 with no or few symptoms, LC2 with some symptoms, and LC3 with many FM symptoms. We analysed putative predictors for these symptom classes using baseline (1975 and 1981) data on regional pain, headache, migraine, sleeping, body mass index (BMI), physical activity, smoking, and zygosity, adjusted for age, gender, and education. Those with a high likelihood of having fibromyalgia at baseline were excluded from the analysis. In the final multivariate regression model, regional pain, sleeping problems, and overweight were all predictors for membership in the class with many FM symptoms. The strongest non-genetic predictor was frequent headache (OR 8.6, CI 95% 3.8-19.2), followed by persistent back pain (OR 4.7, CI 95% 3.3-6.7) and persistent neck pain (OR 3.3, CI 95% 1.8-6.0). Regional pain, frequent headache, and persistent back or neck pain, sleeping problems, and overweight are predictors for having a cluster of symptoms consistent with fibromyalgia.

  12. Adolescent idiopathic scoliosis in twins: a population-based survey

    DEFF Research Database (Denmark)

    Andersen, Mikkel O; Thomsen, Karsten; Kyvik, Kirsten O

    2007-01-01

    STUDY DESIGN: A questionnaire-based identification of adolescent idiopathic scoliosis (AIS) patients in a twin cohort. OBJECTIVE: The purpose of this study was to establish a scoliosis twin cohort to provide data on the heritability of AIS. SUMMARY OF BACKGROUND DATA: The etiology of AIS is still...... environmental factors. METHODS: All 46,418 twins registered in the Danish Twin Registry born from 1931 to 1982 were sent a questionnaire, which included questions about scoliosis. A total of 34,944 (75.3%) representing 23,204 pairs returned the questionnaire. RESULTS: A subgroup of 220 subjects considered...... of monozygotic and dizygotic pairs was significantly different (P scoliosis in 1 twin whose other twin has scoliosis is smaller than believed up until now....

  13. Predictors of medication use in the Roma population in Spain: a population-based national study.

    Science.gov (United States)

    Martín-Pérez, M; Hernández Barrera, V; López de Andrés, A; Jiménez-Trujillo, I; Jiménez-García, R; Carrasco-Garrido, P

    2015-05-01

    To describe the prevalence of prescribed and self-medicated use of medication in the Spanish Roma population, and identify the associated factors. Descriptive cross-sectional study. Data from the first National Health Survey conducted on the Roma population in Spain were used. The sample comprised 1000 Spanish Roma adults of both sexes aged ≥16 years. Answers (yes/no) to the question, 'In the last two weeks have you taken the following medicines [in reference to a list of medicines that might be used by the population] and were they prescribed for you by a doctor?' were used to ascertain 'medication use'. 'Self-medication' referred to use of these medicines without medical prescription. Using multivariate logistic regression models, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to identify associated factors. The overall prevalence of medication use in the Roma population for both sexes was 69.1%, and 38.7% was self-medicated. Females reported higher use of medication than males (75.1% vs 62.3%); however, self-medication was higher among males. Analgesics and antipyretics were used most often (35.8%). Among males, the variables that were independently and significantly associated with a higher probability of medication use were: age; negative perception of health; presence of chronic disease (OR 2.81; 95% CI 1.67-4.73); and medical visits (OR 4.51; 95% CI 2.54-8.01). The variables were the same among females, except for age. A high percentage of the Spanish Roma population use medication, and a significant proportion of them self-medicate. The presence of chronic diseases, a negative perception of health and medical consultations were associated with increased use of medication in the study population. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  14. Recommended methods for monitoring change in bird populations by counting and capture of migrants

    Science.gov (United States)

    David J. T. Hussell; C. John Ralph

    2005-01-01

    Counts and banding captures of spring or fall migrants can generate useful information on the status and trends of the source populations. To do so, the counts and captures must be taken and recorded in a standardized and consistent manner. We present recommendations for field methods for counting and capturing migrants at intensively operated sites, such as bird...

  15. Data Quality in the Application of Tailored Calendar Methods in Hard-to-Reach Populations

    NARCIS (Netherlands)

    Navarra, M.Q.; Vaart, van der W.; Niehof, Anke

    2012-01-01

    Abstract A tailored calendar method was used to collect retrospective data from hard-to-reach populations: people with very low levels of income, education and literacy that live in complex societal situations and have low trust in authorities. Recognizing the serious threats to data quality in

  16. Preventable trauma deaths: from panel review to population based-studies

    Directory of Open Access Journals (Sweden)

    Vesconi Sergio

    2006-04-01

    Full Text Available Abstract Preventable trauma deaths are defined as deaths which could be avoided if optimal care has been delivered. Studies on preventable trauma deaths have been accomplished initially with panel reviews of pre-hospital and hospital charts. However, several investigators questioned the reliability and validity of this method because of low reproducibility of implicit judgments when they are made by different experts. Nevertheless, number of studies were published all around the world and ultimately gained some credibility, particularly in regions where comparisons were made before and after trauma system implementation with a resultant fall in mortality. During the last decade of century the method of comparing observed survival with probability of survival calculated from large trauma registries has obtained popularity. Preventable trauma deaths were identified as deaths occurred notwithstanding a high calculated probability of survival. In recent years, preventable trauma deaths studies have been replaced by population-based studies, which use databases representative of overall population, therefore with high epidemiologic value. These databases contain readily available information which carry out the advantage of objectivity and large numbers. Nowadays, population-based researches provide the strongest evidence regarding the effectiveness of trauma systems and trauma centers on patient outcomes.

  17. Math-Based Simulation Tools and Methods

    National Research Council Canada - National Science Library

    Arepally, Sudhakar

    2007-01-01

    .... The following methods are reviewed: matrix operations, ordinary and partial differential system of equations, Lagrangian operations, Fourier transforms, Taylor Series, Finite Difference Methods, implicit and explicit finite element...

  18. The National Women's Health Study: assembly and description of a population-based reproductive cohort

    Directory of Open Access Journals (Sweden)

    Prior Susan

    2004-08-01

    Full Text Available Abstract Background Miscarriage is a common event but is remarkably difficult to measure in epidemiological studies. Few large-scale population-based studies have been conducted in the UK. Methods This was a population-based two-stage postal survey of reproductive histories of adult women living in the United Kingdom in 2001, sampled from the electronic electoral roll. In Stage 1 a short "screening" questionnaire was sent to over 60,000 randomly selected women in order to identify those aged 55 and under who had ever been pregnant or ever attempted to achieve a pregnancy, from whom a brief reproductive history was requested. Stage 2 involved a more lengthy questionnaire requesting detailed information on every pregnancy (and fertility problems, and questions relating to socio-demographic, behavioural and other factors for the most recent pregnancy in order to examine risk factors for miscarriage. Data on stillbirth, multiple birth and maternal age are compared to national data in order to assess response bias. Results The response rate was 49% for Stage 1 and 73% for the more targeted Stage 2. A total of 26,050 questionnaires were returned in Stage 1. Of the 17,748 women who were eligible on the grounds of age, 27% reported that they had never been pregnant and had never attempted to conceive a child. The remaining 13,035 women reported a total of 30,661 pregnancies. Comparison of key reproductive indicators (stillbirth and multiple birth rates and maternal age at first birth with national statistics showed that the data look remarkably similar to the general population. Conclusions This study has enabled the assembly of a large population-based dataset of women's reproductive histories which appears unbiased compared to the general UK population and which will enable investigation of hard-to-measure outcomes such as miscarriage and infertility.

  19. A moment projection method for population balance dynamics with a shrinkage term

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Shaohua [Department of Mechanical Engineering, National University of Singapore, Engineering Block EA, Engineering Drive 1, 117576 (Singapore); Yapp, Edward K.Y.; Akroyd, Jethro; Mosbach, Sebastian [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3RA (United Kingdom); Xu, Rong [School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore); Yang, Wenming [Department of Mechanical Engineering, National University of Singapore, Engineering Block EA, Engineering Drive 1, 117576 (Singapore); Kraft, Markus, E-mail: mk306@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3RA (United Kingdom); School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore)

    2017-02-01

    A new method of moments for solving the population balance equation is developed and presented. The moment projection method (MPM) is numerically simple and easy to implement and attempts to address the challenge of particle shrinkage due to processes such as oxidation, evaporation or dissolution. It directly solves the moment transport equation for the moments and tracks the number of the smallest particles using the algorithm by Blumstein and Wheeler (1973) . The performance of the new method is measured against the method of moments (MOM) and the hybrid method of moments (HMOM). The results suggest that MPM performs much better than MOM and HMOM where shrinkage is dominant. The new method predicts mean quantities which are almost as accurate as a high-precision stochastic method calculated using the established direct simulation algorithm (DSA).

  20. Celebrity suicides and their differential influence on suicides in the general population: a national population-based study in Korea.

    Science.gov (United States)

    Myung, Woojae; Won, Hong-Hee; Fava, Maurizio; Mischoulon, David; Yeung, Albert; Lee, Dongsoo; Kim, Doh Kwan; Jeon, Hong Jin

    2015-04-01

    Although evidence suggests that there is an increase in suicide rates in the general population following celebrity suicide, the rates are heterogeneous across celebrities and countries. It is unclear which is the more vulnerable population according to the effect sizes of celebrity suicides to general population. All suicide victims in the general population verified by the Korea National Statistical Office and suicides of celebrity in South Korea were included for 7 years from 2005 to 2011. Effect sizes were estimated by comparing rates of suicide in the population one month before and after each celebrity suicide. The associations between suicide victims and celebrities were examined. Among 94,845 suicide victims, 17,209 completed suicide within one month after 13 celebrity suicides. Multivariate logistic regression analyses revealed that suicide victims who died after celebrity suicide were significantly likely to be of age 20-39, female, and to die by hanging. These qualities were more strongly associated among those who followed celebrity suicide with intermediate and high effect sizes than lower. Younger suicide victims were significantly associated with higher effect size, female gender, white collar employment, unmarried status, higher education, death by hanging, and night-time death. Characteristics of celebrities were significantly associated with those of general population in hanging method and gender. Individuals who commit suicide after a celebrity suicide are likely to be younger, female, and prefer hanging as method of suicide, which are more strongly associated in higher effect sizes of celebrity suicide.

  1. Filter-based reconstruction methods for tomography

    NARCIS (Netherlands)

    Pelt, D.M.

    2016-01-01

    In X-ray tomography, a three-dimensional image of the interior of an object is computed from multiple X-ray images, acquired over a range of angles. Two types of methods are commonly used to compute such an image: analytical methods and iterative methods. Analytical methods are computationally

  2. DNA methylation-based variation between human populations.

    Science.gov (United States)

    Kader, Farzeen; Ghai, Meenu

    2017-02-01

    Several studies have proved that DNA methylation affects regulation of gene expression and development. Epigenome-wide studies have reported variation in methylation patterns between populations, including Caucasians, non-Caucasians (Blacks), Hispanics, Arabs, and numerous populations of the African continent. Not only has DNA methylation differences shown to impact externally visible characteristics, but is also a potential biomarker for underlying racial health disparities between human populations. Ethnicity-related methylation differences set their mark during early embryonic development. Genetic variations, such as single-nucleotide polymorphisms and environmental factors, such as age, dietary folate, socioeconomic status, and smoking, impacts DNA methylation levels, which reciprocally impacts expression of phenotypes. Studies show that it is necessary to address these external influences when attempting to differentiate between populations since the relative impacts of these factors on the human methylome remain uncertain. The present review summarises several reported attempts to establish the contribution of differential DNA methylation to natural human variation, and shows that DNA methylation could represent new opportunities for risk stratification and prevention of several diseases amongst populations world-wide. Variation of methylation patterns between human populations is an exciting prospect which inspires further valuable research to apply the concept in routine medical and forensic casework. However, trans-generational inheritance needs to be quantified to decipher the proportion of variation contributed by DNA methylation. The future holds thorough evaluation of the epigenome to understand quantification, heritability, and the effect of DNA methylation on phenotypes. In addition, methylation profiling of the same ethnic groups across geographical locations will shed light on conserved methylation differences in populations.

  3. To the Issue of Application of L. Ron Hubbard Detoxication Method Under the Program of Semipalatinsk Region Population Rehabilitation

    International Nuclear Information System (INIS)

    Apusheva, B.K.; Nurumbetova, R.M.; Tuleubaev, B.A.

    1998-01-01

    The detoxification is one of the most acute problems of the population rehabilitation program of Semipalatinsk region suffered from the nuclear tests in 1949 - 1989. It is known that a Humanitarian Detoxification Service is success-fully functioning in Russia and facilitates the creation of improving centers for the removal of toxic chemical deposits, radiation decay products, and drugs out of the human organism. A method, which permits the successful removal of chemical deposits from the organism, consists of a number of procedures including the intake of a balanced amount of vitamins and minerals, physical exercises and sauna. It is based on the developments of an American scientist L. Ron Hubbard and analytical results of different biologists, physicians and pharmacologists. The effectiveness of the method was confirmed with the numerous clinical tests and examination of over 20,000 patients. The positive results were also obtained during the application of method to the people suffered from the Chernobyl accident. It is proposed to establish such detoxification centre in Kurchatov in order to perform similar investigations among the population of Semipalatinsk region affected by the nuclear testing. It will be created under the auspices of the Kazakh Detoxification Centre and the Pavlodar Centre of the Dianetika International Public Movement. The stable and successive functioning of the Centre is entirely dependent on the financing from the different funds and contract works. This paper proposes the ways of practical solution of man detoxification problem and the introduction of the method into the existing system of population rehabilitation

  4. Primary intramedullary spinal cord lymphoma: a population-based study.

    Science.gov (United States)

    Yang, Wuyang; Garzon-Muvdi, Tomas; Braileanu, Maria; Porras, Jose L; Caplan, Justin M; Rong, Xiaoming; Huang, Judy; Jallo, George I

    2017-03-01

    Primary intramedullary spinal cord lymphoma (PISCL) is a rare diagnosis with poorly understood disease progression. Clarification of the factors associated with survival in PISCL patients is warranted. We conducted a population-based cohort study utilizing prospectively collected data from the Surveillance, Epidemiology, and End Results (SEER) database. Patients with histological diagnosis of primary lymphoma in spinal cord (C72.0) from 1973 to 2012 in the SEER database were included. Multivariable survival analysis between patient, lesion characteristics, and PISCL-related death was performed to adjust for confounding factors. We included 346 PISCL patients in our study. Average age was 56.5 ± 17.8 years, with 62.7% being male. Racial distribution of these patients was white (87.6%), black (8.0%), and other (4.3%). More than half (55.8%) of patients were married. The most prevalent histology of PISCL was diffuse B-cell (46.2%), and the majority (55.2%) were low stage (Ann Arbor stage I/II). Most patients (67.9%) received radiation therapy. Average survival interval of patients with PISCL-related death (n=135, 39.0%) was 27.8 months. General cumulative survival probability at 1 year, 2 years, and 5 years was 73.8%, 67.9%, and 63.1%, respectively. Multivariable accelerated failure time (AFT) regression showed follicular lymphoma (HR:0.25, P=.008) and more recent diagnosis (HR:0.96, P<.001) was positively associated with PISCL-related survival. Conversely, nonwhite race (HR:1.69, P=.046), older age (HR:1.02, P<.001), unmarried status (HR:2.14, P<.001), and higher stage (HR:1.54, P=.022) were negatively associated with survival. Age, race, marital status, tumor histology, tumor stage, and year of diagnosis were associated with survival of PISCL. While most PISCL-related deaths occur within a 1-year period, subsequent slow progression was observed after the first year of survival. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for

  5. Intergenerational teen pregnancy: a population-based cohort study.

    Science.gov (United States)

    Liu, Ning; Vigod, Simone N; Farrugia, M Michèle; Urquia, Marcelo L; Ray, Joel G

    2018-05-22

    To estimate the intergenerational association in teenage pregnancy, and whether there is a coupling tendency between a mother and daughter in how their teen pregnancies end, such as an induced abortion (IA) vs. a livebirth. Population-based cohort study. Ontario, Canada. 15,097 mothers and their 16,177 daughters. Generalized estimating equations generated adjusted odds ratios (aOR) of a daughter experiencing a teen pregnancy in relation to the number of teen pregnancies her mother had. Multinomial logistic regression estimated the odds that a teen pregnancy ended with IA among both mother and daughter. All models were adjusted for maternal age and world region of origin, the daughter's socio-demographic characteristics and comorbidities, mother-daughter cohabitation, and neighborhood-level teen pregnancy rate. Teen pregnancy in the daughter, between ages 15-19 years, and also the nature of the daughter's teen pregnancy, categorized as i) no teen pregnancy, ii) at least one teen pregnancy, all exclusively ending with a livebirth, and iii) at least one teen pregnancy, with at least one teen pregnancy ending with an IA. The proportion of daughters having a teen pregnancy among those whose mother had 0, 1, 2, or ≥ 3 teen pregnancies was 16.3%, 24.9%, 33.5% and 36.3%, respectively. The aOR of a daughter having a teen pregnancy was 1.42 (95% CI 1.25-1.61) if her mother had 1, 1.97 (95% CI 1.71-2.26) if she had 2, and 2.17 (95% CI 1.84-2.56) if her mother had ≥ 3 teen pregnancies, relative to none. If a mother had ≥ 1 teen pregnancy ending with IA, then her daughter had an aOR of 2.12 (95% CI 1.76-2.56) for having a teen pregnancy also ending with IA; whereas, if a mother had ≥ 1 teen pregnancy, all ending with a livebirth, then her daughter had an aOR of 1.73 (95% CI 1.46-2.05) for that same outcome. There is a strong intergenerational occurrence of teenage pregnancy between a mother and daughter, including a coupling tendency in how the pregnancy ends. This

  6. Relative accuracy of three common methods of parentage analysis in natural populations

    KAUST Repository

    Harrison, Hugo B.

    2012-12-27

    Parentage studies and family reconstructions have become increasingly popular for investigating a range of evolutionary, ecological and behavioural processes in natural populations. However, a number of different assignment methods have emerged in common use and the accuracy of each may differ in relation to the number of loci examined, allelic diversity, incomplete sampling of all candidate parents and the presence of genotyping errors. Here, we examine how these factors affect the accuracy of three popular parentage inference methods (colony, famoz and an exclusion-Bayes\\' theorem approach by Christie (Molecular Ecology Resources, 2010a, 10, 115) to resolve true parent-offspring pairs using simulated data. Our findings demonstrate that accuracy increases with the number and diversity of loci. These were clearly the most important factors in obtaining accurate assignments explaining 75-90% of variance in overall accuracy across 60 simulated scenarios. Furthermore, the proportion of candidate parents sampled had a small but significant impact on the susceptibility of each method to either false-positive or false-negative assignments. Within the range of values simulated, colony outperformed FaMoz, which outperformed the exclusion-Bayes\\' theorem method. However, with 20 or more highly polymorphic loci, all methods could be applied with confidence. Our results show that for parentage inference in natural populations, careful consideration of the number and quality of markers will increase the accuracy of assignments and mitigate the effects of incomplete sampling of parental populations. © 2012 Blackwell Publishing Ltd.

  7. Relative accuracy of three common methods of parentage analysis in natural populations

    KAUST Repository

    Harrison, Hugo B.; Saenz Agudelo, Pablo; Planes, Serge; Jones, Geoffrey P.; Berumen, Michael L.

    2012-01-01

    Parentage studies and family reconstructions have become increasingly popular for investigating a range of evolutionary, ecological and behavioural processes in natural populations. However, a number of different assignment methods have emerged in common use and the accuracy of each may differ in relation to the number of loci examined, allelic diversity, incomplete sampling of all candidate parents and the presence of genotyping errors. Here, we examine how these factors affect the accuracy of three popular parentage inference methods (colony, famoz and an exclusion-Bayes' theorem approach by Christie (Molecular Ecology Resources, 2010a, 10, 115) to resolve true parent-offspring pairs using simulated data. Our findings demonstrate that accuracy increases with the number and diversity of loci. These were clearly the most important factors in obtaining accurate assignments explaining 75-90% of variance in overall accuracy across 60 simulated scenarios. Furthermore, the proportion of candidate parents sampled had a small but significant impact on the susceptibility of each method to either false-positive or false-negative assignments. Within the range of values simulated, colony outperformed FaMoz, which outperformed the exclusion-Bayes' theorem method. However, with 20 or more highly polymorphic loci, all methods could be applied with confidence. Our results show that for parentage inference in natural populations, careful consideration of the number and quality of markers will increase the accuracy of assignments and mitigate the effects of incomplete sampling of parental populations. © 2012 Blackwell Publishing Ltd.

  8. Methods for decreasing population doses due to medical use of ionizing radiations

    International Nuclear Information System (INIS)

    Marej, A.N.

    1984-01-01

    The problem of radiation safety of population as regard to irradiation of a great contingents of people due to diagnosis procedures, carried out using X-ray and radiological methods of examination, is considered. It is shown, that prevention from excessive irradiation of population due to X-ray radiodiagnostic procedures is possible by realization the complex of activities, including legislative, organizational, technical and other measures. Human exposure doses in diagnosis most not exceed permissible ones, established on the basis of cost-benefit criterion. The necessity of the maximum limitation of exposure of pregnant women and children is emphasized

  9. Hazard Ranking Method for Populations Exposed to Arsenic in Private Water Supplies: Relation to Bedrock Geology.

    Science.gov (United States)

    Crabbe, Helen; Fletcher, Tony; Close, Rebecca; Watts, Michael J; Ander, E Louise; Smedley, Pauline L; Verlander, Neville Q; Gregory, Martin; Middleton, Daniel R S; Polya, David A; Studden, Mike; Leonardi, Giovanni S

    2017-12-01

    Approximately one million people in the UK are served by private water supplies (PWS) where main municipal water supply system connection is not practical or where PWS is the preferred option. Chronic exposure to contaminants in PWS may have adverse effects on health. South West England is an area with elevated arsenic concentrations in groundwater and over 9000 domestic dwellings here are supplied by PWS. There remains uncertainty as to the extent of the population exposed to arsenic (As), and the factors predicting such exposure. We describe a hazard assessment model based on simplified geology with the potential to predict exposure to As in PWS. Households with a recorded PWS in Cornwall were recruited to take part in a water sampling programme from 2011 to 2013. Bedrock geologies were aggregated and classified into nine Simplified Bedrock Geological Categories (SBGC), plus a cross-cutting "mineralized" area. PWS were sampled by random selection within SBGCs and some 508 households volunteered for the study. Transformations of the data were explored to estimate the distribution of As concentrations for PWS by SBGC. Using the distribution per SBGC, we predict the proportion of dwellings that would be affected by high concentrations and rank the geologies according to hazard. Within most SBGCs, As concentrations were found to have log-normal distributions. Across these areas, the proportion of dwellings predicted to have drinking water over the prescribed concentration value (PCV) for As ranged from 0% to 20%. From these results, a pilot predictive model was developed calculating the proportion of PWS above the PCV for As and hazard ranking supports local decision making and prioritization. With further development and testing, this can help local authorities predict the number of dwellings that might fail the PCV for As, based on bedrock geology. The model presented here for Cornwall could be applied in areas with similar geologies. Application of the method

  10. Dynamics of Cercospora zeina populations in maize-based agro ...

    African Journals Online (AJOL)

    La variation dans le temps au sein d'une population, est fonction de facteurs relatifs à l'écologie, la biologie et l'histoire de vie des pathogènes. Elle varie d'un être vivant à un autre et d'un écosystème à un autre. L'objectif de cette étude était d'évaluer la variabilité génétique au sein des populations de Cercospora zeina ...

  11. Are PCI Service Volumes Associated with 30-Day Mortality? A Population-Based Study from Taiwan.

    Science.gov (United States)

    Yu, Tsung-Hsien; Chou, Ying-Yi; Wei, Chung-Jen; Tung, Yu-Chi

    2017-11-09

    The volume-outcome relationship has been discussed for over 30 years; however, the findings are inconsistent. This might be due to the heterogeneity of service volume definitions and categorization methods. This study takes percutaneous coronary intervention (PCI) as an example to examine whether the service volume was associated with PCI 30-day mortality, given different service volume definitions and categorization methods. A population-based, cross-sectional multilevel study was conducted. Two definitions of physician and hospital volume were used: (1) the cumulative PCI volume in a previous year before each PCI; (2) the cumulative PCI volume within the study period. The volume was further treated in three ways: (1) a categorical variable based on the American Heart Association's recommendation; (2) a semi-data-driven categorical variable based on k-means clustering algorithm; and (3) a data-driven categorical variable based on the Generalized Additive Model. The results showed that, after adjusting the patient-, physician-, and hospital-level covariates, physician volume was associated inversely with PCI 30-day mortality, but hospital volume was not, no matter which definitions and categorization methods of service volume were applied. Physician volume is negatively associated with PCI 30-day mortality, but the results might vary because of definition and categorization method.

  12. Risk perception among women receiving genetic counseling: a population-based follow-up study

    DEFF Research Database (Denmark)

    Mikkelsen, Ellen M; Sunde, Lone; Johansen, Christoffer

    2007-01-01

    -up study of 213 women who received genetic counseling for hereditary breast and ovarian cancer, 319 women who underwent mammography (Reference Group I), and a random sample of 1070 women from the general population (Reference Group II). RESULTS: Women who received genetic counseling decreased...... counseling, compared to a reduction of 5% (p=0.03) and 2% (p=0.01) in Reference Groups I and II, respectively. Risk communicated only in words, inaccurate risk perception at baseline, and presence of a familial mutation appeared to be predictors of inaccurate risk perception 12 months after counseling......BACKGROUND: We aimed to explore the impact of genetic counseling on perceived personal lifetime risk of breast cancer, the accuracy of risk perception, and possible predictors of inaccurate risk perception 1 year following counseling. METHODS: We conducted a population-based prospective follow...

  13. Lithium and renal and upper urinary tract tumors - results from a nationwide population-based study

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Gerds, Thomas Alexander; Feldt-Rasmussen, Bo

    2015-01-01

    OBJECTIVES: A recent alarming finding suggested an increased risk of renal tumors among long-term lithium users. The objectives of the present study were to estimate rates of renal and upper urinary tract tumors (RUT), malignant and benign, among individuals exposed to successive prescriptions...... for lithium, anticonvulsants, and other psychotropic agents used for bipolar disorder, and among unexposed individuals. METHODS: This was a nationwide, population-based longitudinal study including time-specific data from all individuals exposed to lithium (n = 24,272) or anticonvulsants (n = 386,255), all...... individuals with a diagnosis of bipolar disorder (n = 9,651), and a randomly selected sample of 1,500,000 from the Danish population. The study period was from 1995 to 2012, inclusive. Outcomes were hazard rate ratios (HR) for RUT in three groups: (i) combined malignant and benign, (ii) malignant, and (iii...

  14. OA18 Population based end of life care - meeting the challenge of the ageing population.

    Science.gov (United States)

    Thomas, Keri

    2015-04-01

    The key challenge for most developed countries is meeting the needs of our ageing population, in particular, those nearing the end of their lives - population-based end-of-life care. Building on a public health approach to meet needs of an area-wide population, and a practical approach of enabling generalist frontline staff care for all people in a variety of settings using the GSF Quality Improvement Programmes, we describe progress in a few GSF Cross-Boundary Care Foundation Sites taking a population-based view to meet the challenges of the ageing population. Taking a whole-system view, we explore ways to ensure all people receive quality care towards the final stages of life in line with their needs and wishes in a way that is cost-effective, responsive and compassionate. Expanding concepts of palliative/end-of-life care to include care for people with long-term conditions, dementia, and frailty. We describe practical progress in a number of GSF XBC Sites, enabling generalist frontline staff including: Identifying and prioritising people earlier Reducing 'diagnostic apartheid' Enabling more to live well and die well in the place and manner of their choosing Encouraging integrated person-centred care, reducing inappropriate over-Hospitalisation and prevention of over - medicalising. Use of GSF in various settings to enable generalist frontline staff is described, with key outcome measures and evaluations in the UK, and internationally. As the population ages, population-based end of life care will be one of the most significant developments to meet the challenges for a fit-for-purpose health service of the future. © 2015, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. An Updating System for the Gridded Population Database of China Based on Remote Sensing, GIS and Spatial Database Technologies

    Science.gov (United States)

    Yang, Xiaohuan; Huang, Yaohuan; Dong, Pinliang; Jiang, Dong; Liu, Honghui

    2009-01-01

    The spatial distribution of population is closely related to land use and land cover (LULC) patterns on both regional and global scales. Population can be redistributed onto geo-referenced square grids according to this relation. In the past decades, various approaches to monitoring LULC using remote sensing and Geographic Information Systems (GIS) have been developed, which makes it possible for efficient updating of geo-referenced population data. A Spatial Population Updating System (SPUS) is developed for updating the gridded population database of China based on remote sensing, GIS and spatial database technologies, with a spatial resolution of 1 km by 1 km. The SPUS can process standard Moderate Resolution Imaging Spectroradiometer (MODIS L1B) data integrated with a Pattern Decomposition Method (PDM) and an LULC-Conversion Model to obtain patterns of land use and land cover, and provide input parameters for a Population Spatialization Model (PSM). The PSM embedded in SPUS is used for generating 1 km by 1 km gridded population data in each population distribution region based on natural and socio-economic variables. Validation results from finer township-level census data of Yishui County suggest that the gridded population database produced by the SPUS is reliable. PMID:22399959

  16. An Updating System for the Gridded Population Database of China Based on Remote Sensing, GIS and Spatial Database Technologies

    Directory of Open Access Journals (Sweden)

    Xiaohuan Yang

    2009-02-01

    Full Text Available The spatial distribution of population is closely related to land use and land cover (LULC patterns on both regional and global scales. Population can be redistributed onto geo-referenced square grids according to this relation. In the past decades, various approaches to monitoring LULC using remote sensing and Geographic Information Systems (GIS have been developed, which makes it possible for efficient updating of geo-referenced population data. A Spatial Population Updating System (SPUS is developed for updating the gridded population database of China based on remote sensing, GIS and spatial database technologies, with a spatial resolution of 1 km by 1 km. The SPUS can process standard Moderate Resolution Imaging Spectroradiometer (MODIS L1B data integrated with a Pattern Decomposition Method (PDM and an LULC-Conversion Model to obtain patterns of land use and land cover, and provide input parameters for a Population Spatialization Model (PSM. The PSM embedded in SPUS is used for generating 1 km by 1 km gridded population data in each population distribution region based on natural and socio-economic variables. Validation results from finer township-level census data of Yishui County suggest that the gridded population database produced by the SPUS is reliable.

  17. Congenital anomalies in children with cerebral palsy: a population-based record linkage study

    DEFF Research Database (Denmark)

    Rankin, Judith; Cans, Christine; Garne, Ester

    2009-01-01

    Aim Our aim was to determine the proportion of children with cerebral palsy (CP) who have a congenital anomaly (CA) in three regions (Isère Region, French Alps; Funen County, Denmark; Northern Region, England) where population-based CP and CA registries exist, and to classify the children according...... to CA subtype. Method Data for children born between 1991 and 1999 were linked using electronic matching of cases. All potential matches were checked manually by each centre and verified as true matches. Results A total of 1104 children with CP were born during the study period (663 males, 441 females...

  18. Fertility rates and perinatal outcomes of adolescent pregnancies: a retrospective population-based study

    OpenAIRE

    Souza, Maria de Lourdes de; Lynn, Fiona Ann; Johnston, Linda; Tavares, Eduardo Cardoso Teixeira; Brüggemann, Odaléa Maria; Botelho, Lúcio José

    2017-01-01

    ABSTRACT Objective: analyze trends in fertility rates and associations with perinatal outcomes for adolescents in Santa Catarina, Brazil. Methods: a population-based study covering 2006 to 2013 was carried out to evaluate associations between perinatal outcomes and age groups, using odds ratios, and Chi-squared tests. Results: differences in the fertility rate among female adolescents across regions and time period were observed, ranging from 40.9 to 72.0 per 1,000 in mothers aged 15-19 ye...

  19. Autoimmune and immunogenetic profile of patients with optic neuritis in a population-based cohort

    DEFF Research Database (Denmark)

    Soelberg, K.; Nilsson, A. C.; Nielsen, C.

    2018-01-01

    Background: Optic neuritis (ON) is an inflammatory optic neuropathy, where the genetic and autoimmune dependency remains poorly characterized. Objective: To investigate autoimmune and immunogenetic aspects of ON. Method: In a prospective population-based cohort 51 patients with ON were included...... antibodies. Coexisting neural autoantibodies were detected in two patients and in 12 patients other systemic autoantibodies were found. Four (8%) had other autoimmune disorders. A family history of autoimmunity was observed in 12 (24%) and of demyelinating disease in six patients (12%). In MS-ON patients...

  20. Dietary Patterns Associated with Alzheimer’s Disease: Population Based Study

    Directory of Open Access Journals (Sweden)

    Katarzyna Gustaw-Rothenberg

    2009-04-01

    Full Text Available Recently dietary pattern analysis has emerged as a way for examining diet-disease relations in Alzheimer’s disease. In contrast with the conventional approach, which focuses on a single nutrient or a few nutrients or foods, this method considers overall eating patterns. We examined the dietary patterns defined by factor analysis using data collected with a food-frequency questionnaire in people with Alzheimer’s disease (AD as compared to healthy controls. The diet data were obtained during population based study of the prevalence of Alzheimer’s disease in a population in Poland. Stratified sampling and random selection strategies were combined to obtain a representative population for screening (age group > 55. From the population screened three times, 71 people were diagnosed with Alzheimer’s according to DSM-IV, and were recruited for further diet risk factors assessment. A group of people with Alzheimer disease (n = 71; F/M 42/29 and the same number of healthy, age and gender matched control were recruited for the study. Patients and their caregivers as well as controls were presented with a food frequency questionnaire based on the 12 food groups. Factor analysis (principal component was used to derive food patterns. The analysis was conducted using the factor procedure. The factors were rotated by an orthogonal transformation (Varimax rotation to achieve simpler structure with greater interpretability. Using factor analysis, we identified major eating patterns, one for Alzheimer’s patients and a different one for control group. The AD dietary pattern, FACTOR AD was characterized by a high intake of meat, butter, high-fat dairy products, eggs, and refined sugar, whereas the other pattern, (FACTOR C was characterized by a high intake of grains and vegetables. These data indicate the existence of dietary patterns defined by factor analysis with data from a food frequency questionnaire, characteristic for Alzheimer’s disease in a

  1. The influence of population characteristics on variation in general practice based morbidity estimations

    Directory of Open Access Journals (Sweden)

    van den Dungen C

    2011-11-01

    Full Text Available Abstract Background General practice based registration networks (GPRNs provide information on morbidity rates in the population. Morbidity rate estimates from different GPRNs, however, reveal considerable, unexplained differences. We studied the range and variation in morbidity estimates, as well as the extent to which the differences in morbidity rates between general practices and networks change if socio-demographic characteristics of the listed patient populations are taken into account. Methods The variation in incidence and prevalence rates of thirteen diseases among six Dutch GPRNs and the influence of age, gender, socio economic status (SES, urbanization level, and ethnicity are analyzed using multilevel logistic regression analysis. Results are expressed in median odds ratios (MOR. Results We observed large differences in morbidity rate estimates both on the level of general practices as on the level of networks. The differences in SES, urbanization level and ethnicity distribution among the networks' practice populations are substantial. The variation in morbidity rate estimates among networks did not decrease after adjusting for these socio-demographic characteristics. Conclusion Socio-demographic characteristics of populations do not explain the differences in morbidity estimations among GPRNs.

  2. Genetic diversity of Ghanaian local chicken populations based on ...

    African Journals Online (AJOL)

    In Ghana, local chickens are raised across distinct agro-ecological zones and constitute unique populations with variable phenotypes that need to be characterized to provide needed information for the conservation of useful genotypes against future needs. In particular, the Interior Savannah (GHIS) in the north, the Forest ...

  3. Genetic structure of Balearic honeybee populations based on microsatellite polymorphism

    Directory of Open Access Journals (Sweden)

    Moritz Robin FA

    2003-05-01

    Full Text Available Abstract The genetic variation of honeybee colonies collected in 22 localities on the Balearic Islands (Spain was analysed using eight polymorphic microsatellite loci. Previous studies have demonstrated that these colonies belong either to the African or west European evolutionary lineages. These populations display low variability estimated from both the number of alleles and heterozygosity values, as expected for the honeybee island populations. Although genetic differentiation within the islands is low, significant heterozygote deficiency is present, indicating a subpopulation genetic structure. According to the genetic differentiation test, the honeybee populations of the Balearic Islands cluster into two groups: Gimnesias (Mallorca and Menorca and Pitiusas (Ibiza and Formentera, which agrees with the biogeography postulated for this archipelago. The phylogenetic analysis suggests an Iberian origin of the Balearic honeybees, thus confirming the postulated evolutionary scenario for Apis mellifera in the Mediterranean basin. The microsatellite data from Formentera, Ibiza and Menorca show that ancestral populations are threatened by queen importations, indicating that adequate conservation measures should be developed for protecting Balearic bees.

  4. Genetic diversity of Kenyan Prosopis populations based on random ...

    African Journals Online (AJOL)

    To determine whether naturally established stands consist of a single or mixture of species, six populations from Bamburi, Bura, Isiolo, Marigat, Taveta and Turkwel were compared for relatedness with reference to Prosopis chilensis, Prosopis juliflora and Prosopis pallida using random amplified polymorphic DNA markers.

  5. Vascular Pathology And Osteoarthritis Population-based studies

    NARCIS (Netherlands)

    T.A. Hoeven (Theun)

    2014-01-01

    markdownabstract__Abstract__ Osteoarthritis (OA) is the most frequent joint disorder worldwide and causes a considerable burden of pain, disability, and ever increasing costs to society. Due to rapid ageing and the epidemic of obesity in western populations, prevalence of OA is expected

  6. A stage-based model of manatee population dynamics

    Science.gov (United States)

    Runge, M.C.; Langtimm, C.A.; Kendall, W.L.

    2004-01-01

    A stage-structured population model for the Florida manatee (Trichechus manatus latirostris) was developed that explicitly incorporates uncertainty in parameter estimates. The growth rates calculated with this model reflect the status of the regional populations over the most recent 10-yr period. The Northwest and Upper St. Johns River regions have growth rates (8) of 1.037 (95% interval, 1.016?1.056) and 1.062 (1.037?1.081), respectively. The Southwest region has a growth rate of 0.989 (0.946?1.024), suggesting this population has been declining at about 1.1% per year. The estimated growth rate in the Atlantic region is 1.010 (0.988?1.029), but there is some uncertainty about whether adult survival rates have been constant over the last 10 yr; using the mean survival rates from the most recent 5-yr period, the estimated growth rate in this region is 0.970 (0.938?0.998). Elasticity analysis indicates that the most effective management actions should seek to increase adult survival rates. Decomposition of the uncertainty in the growth rates indicates that uncertainty about population status can best be reduced through increased monitoring of adult survival rate.

  7. Sleep in later life: a population-based approach

    NARCIS (Netherlands)

    J.F. van den Berg (Julia)

    2008-01-01

    textabstractThis dissertation includes six epidemiological studies of sleep in a normal elderly population. The research was conducted within the setting of the Rotterdam Study, a large prospective cohort study of community-dwelling inhabitants of a district of Rotterdam, aged 55 and over. A total

  8. Triptycene-based ladder monomers and polymers, methods of making each, and methods of use

    KAUST Repository

    Pinnau, Ingo

    2015-02-05

    Embodiments of the present disclosure provide for a triptycene-based A-B monomer, a method of making a triptycene-based A-B monomer, a triptycene-based ladder polymer, a method of making a triptycene-based ladder polymers, a method of using triptycene-based ladder polymers, a structure incorporating triptycene-based ladder polymers, a method of gas separation, and the like.

  9. Alternative methods of flexible base compaction acceptance.

    Science.gov (United States)

    2012-11-01

    "This report presents the results from the second year of research work investigating issues with flexible base acceptance testing within the Texas Department of Transportation. This second year of work focused on shadow testing non-density-based acc...

  10. A method for analyzing changing prison populations: explaining the growth of the elderly in prison.

    Science.gov (United States)

    Luallen, Jeremy; Kling, Ryan

    2014-12-01

    For the past several decades, the U.S. prison system has witnessed a steady and persistent increase in the ages of prison populations. Given the additional costs and burdens placed on prisons as they house older inmates, this aging trend has generated intense interest among policy makers and academics who seek to understand why prison populations are getting older. This article presents a method for evaluating drivers influencing the change in age distributions among prisoners. We define a methodological approach and demonstrate its application using prison data from four states reporting to the Bureau of Justice Statistics' National Corrections Reporting Program. We find that since 2000, the primary driver of overall growth in the elderly populations in prison (defined as inmates over 50) is the increasing admission age of offenders entering prison. Moreover, changes in offense mix and sentence length/time served over the last decade have had significantly less influence on the age composition of prison populations. We also find that the impact of explanatory factors varies across states and offense types. For example, prison admission and exit rates explain much of the change in elderly drug offenders in New York, but not elderly violent offenders, where admission age plays a much stronger explanatory role. Our analysis offers an effective demonstration that supports the use of this method as an important and informative first step toward understanding components of change that affect the problem of prison aging. © The Author(s) 2014.

  11. Landscape-based population viability models demonstrate importance of strategic conservation planning for birds

    Science.gov (United States)

    Thomas W. Bonnot; Frank R. Thompson; Joshua J. Millspaugh; D. Todd. Jones-Farland

    2013-01-01

    Efforts to conserve regional biodiversity in the face of global climate change, habitat loss and fragmentation will depend on approaches that consider population processes at multiple scales. By combining habitat and demographic modeling, landscape-based population viability models effectively relate small-scale habitat and landscape patterns to regional population...

  12. Math-Based Simulation Tools and Methods

    National Research Council Canada - National Science Library

    Arepally, Sudhakar

    2007-01-01

    ...: HMMWV 30-mph Rollover Test, Soldier Gear Effects, Occupant Performance in Blast Effects, Anthropomorphic Test Device, Human Models, Rigid Body Modeling, Finite Element Methods, Injury Criteria...

  13. Energy demand forecasting method based on international statistical data

    International Nuclear Information System (INIS)

    Glanc, Z.; Kerner, A.

    1997-01-01

    Poland is in a transition phase from a centrally planned to a market economy; data collected under former economic conditions do not reflect a market economy. Final energy demand forecasts are based on the assumption that the economic transformation in Poland will gradually lead the Polish economy, technologies and modes of energy use, to the same conditions as mature market economy countries. The starting point has a significant influence on the future energy demand and supply structure: final energy consumption per capita in 1992 was almost half the average of OECD countries; energy intensity, based on Purchasing Power Parities (PPP) and referred to GDP, is more than 3 times higher in Poland. A method of final energy demand forecasting based on regression analysis is described in this paper. The input data are: output of macroeconomic and population growth forecast; time series 1970-1992 of OECD countries concerning both macroeconomic characteristics and energy consumption; and energy balance of Poland for the base year of the forecast horizon. (author). 1 ref., 19 figs, 4 tabs

  14. Energy demand forecasting method based on international statistical data

    Energy Technology Data Exchange (ETDEWEB)

    Glanc, Z; Kerner, A [Energy Information Centre, Warsaw (Poland)

    1997-09-01

    Poland is in a transition phase from a centrally planned to a market economy; data collected under former economic conditions do not reflect a market economy. Final energy demand forecasts are based on the assumption that the economic transformation in Poland will gradually lead the Polish economy, technologies and modes of energy use, to the same conditions as mature market economy countries. The starting point has a significant influence on the future energy demand and supply structure: final energy consumption per capita in 1992 was almost half the average of OECD countries; energy intensity, based on Purchasing Power Parities (PPP) and referred to GDP, is more than 3 times higher in Poland. A method of final energy demand forecasting based on regression analysis is described in this paper. The input data are: output of macroeconomic and population growth forecast; time series 1970-1992 of OECD countries concerning both macroeconomic characteristics and energy consumption; and energy balance of Poland for the base year of the forecast horizon. (author). 1 ref., 19 figs, 4 tabs.

  15. Bayesian Population Physiologically-Based Pharmacokinetic (PBPK Approach for a Physiologically Realistic Characterization of Interindividual Variability in Clinically Relevant Populations.

    Directory of Open Access Journals (Sweden)

    Markus Krauss

    Full Text Available Interindividual variability in anatomical and physiological properties results in significant differences in drug pharmacokinetics. The consideration of such pharmacokinetic variability supports optimal drug efficacy and safety for each single individual, e.g. by identification of individual-specific dosings. One clear objective in clinical drug development is therefore a thorough characterization of the physiological sources of interindividual variability. In this work, we present a Bayesian population physiologically-based pharmacokinetic (PBPK approach for the mechanistically and physiologically realistic identification of interindividual variability. The consideration of a generic and highly detailed mechanistic PBPK model structure enables the integration of large amounts of prior physiological knowledge, which is then updated with new experimental data in a Bayesian framework. A covariate model integrates known relationships of physiological parameters to age, gender and body height. We further provide a framework for estimation of the a posteriori parameter dependency structure at the population level. The approach is demonstrated considering a cohort of healthy individuals and theophylline as an application example. The variability and co-variability of physiological parameters are specified within the population; respectively. Significant correlations are identified between population parameters and are applied for individual- and population-specific visual predictive checks of the pharmacokinetic behavior, which leads to improved results compared to present population approaches. In the future, the integration of a generic PBPK model into an hierarchical approach allows for extrapolations to other populations or drugs, while the Bayesian paradigm allows for an iterative application of the approach and thereby a continuous updating of physiological knowledge with new data. This will facilitate decision making e.g. from preclinical to

  16. Population based study of fatigue and psychological distress.

    OpenAIRE

    Pawlikowska, T.; Chalder, T.; Hirsch, S. R.; Wallace, P.; Wright, D. J.; Wessely, S. C.

    1994-01-01

    OBJECTIVES--To determine the prevalence of fatigue in the general population and the factors associated with fatigue. DESIGN--Postal survey. SETTING--Six general practices in southern England. SUBJECTS--31,651 men and women aged 18-45 years registered with the practices. MAIN OUTCOME MEASURES--Responses to the 12 item general health questionnaire and a fatigue questionnaire which included self reported measures of duration, severity, and causes of fatigue. RESULTS--15,283 valid questionnaires...

  17. "Health divide" between indigenous and non-indigenous populations in Kerala, India: population based study.

    Science.gov (United States)

    Haddad, Slim; Mohindra, Katia Sarla; Siekmans, Kendra; Màk, Geneviève; Narayana, Delampady

    2012-05-29

    The objective of this study is to investigate the magnitude and nature of health inequalities between indigenous (Scheduled Tribes) and non-indigenous populations, as well as between different indigenous groups, in a rural district of Kerala State, India. A health survey was carried out in a rural community (N = 1660 men and women, 18-96 years). Age- and sex-standardised prevalence of underweight (BMI populations. Multi-level weighted logistic regression models were used to estimate the predicted prevalence of morbidity for each age and social group. A Blinder-Oaxaca decomposition was used to further explore the health gap between tribes and non-tribes, and between subgroups of tribes. Social stratification remains a strong determinant of health in the progressive social policy environment of Kerala. The tribal groups are bearing a higher burden of underweight (46.1 vs. 24.3%), anaemia (9.9 vs. 3.5%) and goitre (8.5 vs. 3.6%) compared to non-tribes, but have similar levels of tuberculosis (21.4 vs. 20.4%) and hypertension (23.5 vs. 20.1%). Significant health inequalities also exist within tribal populations; the Paniya have higher levels of underweight (54.8 vs. 40.7%) and anaemia (17.2 vs. 5.7%) than other Scheduled Tribes. The social gradient in health is evident in each age group, with the exception of hypertension. The predicted prevalence of underweight is 31 and 13 percentage points higher for Paniya and other Scheduled Tribe members, respectively, compared to Forward Caste members 18-30 y (27.1%). Higher hypertension is only evident among Paniya adults 18-30 y (10 percentage points higher than Forward Caste adults of the same age group (5.4%)). The decomposition analysis shows that poverty and other determinants of health only explain 51% and 42% of the health gap between tribes and non-tribes for underweight and goitre, respectively. Policies and programmes designed to benefit the Scheduled Tribes need to promote their well-being in general but

  18. Friendship-based partner switching promotes cooperation in heterogeneous populations

    Science.gov (United States)

    Chen, Wei; Wu, Te; Li, Zhiwu; Wang, Long

    2016-02-01

    The forming of human social ties tends to be with similar individuals. This study concentrates on the emergence of cooperation among heterogeneous populations. A simple model is proposed by considering the impact of interplay between the evolution of strategies and that of social partnerships on cooperation dynamics. Whenever two individuals acquire the rewards by playing prisoner's dilemma game with each other, the friendship (friendship is quantified as the weight of a link) between the two individuals deepens. Individuals can switch off the social ties with the partners who are unfriendly and rewire to similar new ones. Under this partner switching mechanism, population structure is divided into several groups and cooperation can prevail. It is observed that the frequent tendency of partner switching can lead to the enhancement of cooperative behavior under the enormous temptation to defect. Moreover, the influence of discounting the relationship between different individuals is also investigated. Meanwhile, the cooperation prevails when the adjustment of friendships mainly depends on the incomes of selected individuals rather than that of their partners. Finally, it is found that too similar population fail to maximize the cooperation and there exists a moderate similarity that can optimize cooperation.

  19. Hurricane Loss Analysis Based on the Population-Weighted Index

    Directory of Open Access Journals (Sweden)

    Grzegorz Kakareko

    2017-08-01

    Full Text Available This paper discusses different measures for quantifying regional hurricane loss. The main measures used in the past are normalized percentage loss and dollar value loss. In this research, we show that these measures are useful but may not properly reflect the size of the population influenced by hurricanes. A new loss measure is proposed that reflects the hurricane impact on people occupying the structure. For demonstrating the differences among these metrics, regional loss analysis was conducted for Florida. The regional analysis was composed of three modules: the hazard module stochastically modeled the wind occurrence in the region; the vulnerability module utilized vulnerability functions developed in this research to calculate the loss; and the financial module quantified the hurricane loss. In the financial module, we calculated three loss metrics for certain region. The first metric is the average annual loss (AAL which represents the expected loss per year in percentage. The second is the average annual dollar loss which represents the expected dollar amount loss per year. The third is the average annual population-weighted loss (AAPL—a new measure proposed in this research. Compared with the AAL, the AAPL reflects the number of people influenced by the hurricane. The advantages of the AAPL are illustrated using three different analysis examples: (1 conventional regional loss analysis, (2 mitigation potential analysis, and (3 forecasted future loss analysis due to the change in population.

  20. A phylogenetic method to perform genome-wide association studies in microbes that accounts for population structure and recombination.

    Directory of Open Access Journals (Sweden)

    Caitlin Collins

    2018-02-01

    Full Text Available Genome-Wide Association Studies (GWAS in microbial organisms have the potential to vastly improve the way we understand, manage, and treat infectious diseases. Yet, microbial GWAS methods established thus far remain insufficiently able to capitalise on the growing wealth of bacterial and viral genetic sequence data. Facing clonal population structure and homologous recombination, existing GWAS methods struggle to achieve both the precision necessary to reject spurious findings and the power required to detect associations in microbes. In this paper, we introduce a novel phylogenetic approach that has been tailor-made for microbial GWAS, which is applicable to organisms ranging from purely clonal to frequently recombining, and to both binary and continuous phenotypes. Our approach is robust to the confounding effects of both population structure and recombination, while maintaining high statistical power to detect associations. Thorough testing via application to simulated data provides strong support for the power and specificity of our approach and demonstrates the advantages offered over alternative cluster-based and dimension-reduction methods. Two applications to Neisseria meningitidis illustrate the versatility and potential of our method, confirming previously-identified penicillin resistance loci and resulting in the identification of both well-characterised and novel drivers of invasive disease. Our method is implemented as an open-source R package called treeWAS which is freely available at https://github.com/caitiecollins/treeWAS.

  1. Somatic symptom profiles in the general population: a latent class analysis in a Danish population-based health survey

    DEFF Research Database (Denmark)

    Eliasen, Marie; Torben, Jørgensen; Schröder, Andreas Bak

    2017-01-01

    PURPOSE: The aim of this study was to identify and describe somatic symptom profiles in the general adult population in order to enable further epidemiological research within multiple somatic symptoms. METHODS: Information on 19 self-reported common somatic symptoms was achieved from a population....... The profiles were further described by their association with age, sex, chronic disease, and self-perceived health. RESULTS: We identified 10 different somatic symptom profiles defined by number, type, and site of the symptoms. The majority of the population (74.0%) had a profile characterized......, and self-perceived health. CONCLUSION: The identified somatic symptom profiles could be distinguished by number, type, and site of the symptoms. The profiles have the potential to be used in further epidemiological studies on risk factors and prognosis of somatic symptoms but should be confirmed in other...

  2. Evaluation bases for calculation methods in radioecology

    International Nuclear Information System (INIS)

    Bleck-Neuhaus, J.; Boikat, U.; Franke, B.; Hinrichsen, K.; Hoepfner, U.; Ratka, R.; Steinhilber-Schwab, B.; Teufel, D.; Urbach, M.

    1982-03-01

    The seven contributions in this book deal with the state and problems of radioecology. In particular it analyses: The propagation of radioactive materials in the atmosphere, the transfer of radioactive substances from the soil into plants, respectively from animal feed into meat, the exposure pathways for, and high-risk groups of the population, the uncertainties and the band width of the ingestion factor, as well as the treatment of questions of radioecology in practice. The calculation model is assessed and the difficulty evaluated of laying down data in the general calculation basis. (DG) [de

  3. Cardiovascular Disease Risk in a Large, Population-Based Cohort of Breast Cancer Survivors

    Energy Technology Data Exchange (ETDEWEB)

    Boekel, Naomi B.; Schaapveld, Michael [Epidemiology, Netherlands Cancer Institute, Amsterdam (Netherlands); Gietema, Jourik A. [Medical Oncology, University Medical Center Groningen, Groningen (Netherlands); Russell, Nicola S. [Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Poortmans, Philip [Radiation Oncology, Institute Verbeeten, Tilburg (Netherlands); Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Theuws, Jacqueline C.M. [Radiotherapy, Catharina Hospital Eindhoven, Eindhoven (Netherlands); Schinagl, Dominic A.X. [Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Rietveld, Derek H.F. [Radiation Oncology, VU University Medical Center Amsterdam, Amsterdam (Netherlands); Versteegh, Michel I.M. [Steering Committee Cardiac Interventions Netherlands, Leiden University Medical Center, Leiden (Netherlands); Visser, Otto [Registration and Research, Comprehensive Cancer Center The Netherlands, Utrecht (Netherlands); Rutgers, Emiel J.T. [Surgery, Netherlands Cancer Institute, Amsterdam (Netherlands); Aleman, Berthe M.P. [Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Leeuwen, Flora E. van, E-mail: f.v.leeuwen@nki.nl [Epidemiology, Netherlands Cancer Institute, Amsterdam (Netherlands)

    2016-04-01

    Purpose: To conduct a large, population-based study on cardiovascular disease (CVD) in breast cancer (BC) survivors treated in 1989 or later. Methods and Materials: A large, population-based cohort comprising 70,230 surgically treated stage I to III BC patients diagnosed before age 75 years between 1989 and 2005 was linked with population-based registries for CVD. Cardiovascular disease risks were compared with the general population, and within the cohort using competing risk analyses. Results: Compared with the general Dutch population, BC patients had a slightly lower CVD mortality risk (standardized mortality ratio 0.92, 95% confidence interval [CI] 0.88-0.97). Only death due to valvular heart disease was more frequent (standardized mortality ratio 1.28, 95% CI 1.08-1.52). Left-sided radiation therapy after mastectomy increased the risk of any cardiovascular event compared with both surgery alone (subdistribution hazard ratio (sHR) 1.23, 95% CI 1.11-1.36) and right-sided radiation therapy (sHR 1.19, 95% CI 1.04-1.36). Radiation-associated risks were found for not only ischemic heart disease, but also for valvular heart disease and congestive heart failure (CHF). Risks were more pronounced in patients aged <50 years at BC diagnosis (sHR 1.48, 95% CI 1.07-2.04 for left- vs right-sided radiation therapy after mastectomy). Left- versus right-sided radiation therapy after wide local excision did not increase the risk of all CVD combined, yet an increased ischemic heart disease risk was found (sHR 1.14, 95% CI 1.01-1.28). Analyses including detailed radiation therapy information showed an increased CVD risk for left-sided chest wall irradiation alone, left-sided breast irradiation alone, and internal mammary chain field irradiation, all compared with right-sided breast irradiation alone. Compared with patients not treated with chemotherapy, chemotherapy used ≥1997 (ie, anthracyline-based chemotherapy) increased the risk of CHF (sHR 1.35, 95% CI 1

  4. Cardiovascular Disease Risk in a Large, Population-Based Cohort of Breast Cancer Survivors

    International Nuclear Information System (INIS)

    Boekel, Naomi B.; Schaapveld, Michael; Gietema, Jourik A.; Russell, Nicola S.; Poortmans, Philip; Theuws, Jacqueline C.M.; Schinagl, Dominic A.X.; Rietveld, Derek H.F.; Versteegh, Michel I.M.; Visser, Otto; Rutgers, Emiel J.T.; Aleman, Berthe M.P.; Leeuwen, Flora E. van

    2016-01-01

    Purpose: To conduct a large, population-based study on cardiovascular disease (CVD) in breast cancer (BC) survivors treated in 1989 or later. Methods and Materials: A large, population-based cohort comprising 70,230 surgically treated stage I to III BC patients diagnosed before age 75 years between 1989 and 2005 was linked with population-based registries for CVD. Cardiovascular disease risks were compared with the general population, and within the cohort using competing risk analyses. Results: Compared with the general Dutch population, BC patients had a slightly lower CVD mortality risk (standardized mortality ratio 0.92, 95% confidence interval [CI] 0.88-0.97). Only death due to valvular heart disease was more frequent (standardized mortality ratio 1.28, 95% CI 1.08-1.52). Left-sided radiation therapy after mastectomy increased the risk of any cardiovascular event compared with both surgery alone (subdistribution hazard ratio (sHR) 1.23, 95% CI 1.11-1.36) and right-sided radiation therapy (sHR 1.19, 95% CI 1.04-1.36). Radiation-associated risks were found for not only ischemic heart disease, but also for valvular heart disease and congestive heart failure (CHF). Risks were more pronounced in patients aged <50 years at BC diagnosis (sHR 1.48, 95% CI 1.07-2.04 for left- vs right-sided radiation therapy after mastectomy). Left- versus right-sided radiation therapy after wide local excision did not increase the risk of all CVD combined, yet an increased ischemic heart disease risk was found (sHR 1.14, 95% CI 1.01-1.28). Analyses including detailed radiation therapy information showed an increased CVD risk for left-sided chest wall irradiation alone, left-sided breast irradiation alone, and internal mammary chain field irradiation, all compared with right-sided breast irradiation alone. Compared with patients not treated with chemotherapy, chemotherapy used ≥1997 (ie, anthracyline-based chemotherapy) increased the risk of CHF (sHR 1.35, 95% CI 1

  5. Neurophysiological Based Methods of Guided Image Search

    National Research Council Canada - National Science Library

    Marchak, Frank

    2003-01-01

    .... We developed a model of visual feature detection, the Neuronal Synchrony Model, based on neurophysiological models of temporal neuronal processing, to improve the accuracy of automatic detection...

  6. Triptycene-based ladder monomers and polymers, methods of making each, and methods of use

    KAUST Repository

    Pinnau, Ingo; Ghanem, Bader; Swaidan, Raja

    2015-01-01

    Embodiments of the present disclosure provide for a triptycene-based A-B monomer, a method of making a triptycene-based A-B monomer, a triptycene-based ladder polymer, a method of making a triptycene-based ladder polymers, a method of using

  7. Multi-atlas labeling with population-specific template and non-local patch-based label fusion

    DEFF Research Database (Denmark)

    Fonov, Vladimir; Coupé, Pierrick; Eskildsen, Simon Fristed

    We propose a new method combining a population-specific nonlinear template atlas approach with non-local patch-based structure segmentation for whole brain segmentation into individual structures. This way, we benefit from the efficient intensity-driven segmentation of the non-local means framework...... and from the global shape constraints imposed by the nonlinear template matching....

  8. Men's and Women's Health Beliefs Differentially Predict Coronary Heart Disease Incidence in a Population-Based Sample

    Science.gov (United States)

    Korin, Maya Rom; Chaplin, William F.; Shaffer, Jonathan A.; Butler, Mark J.; Ojie, Mary-Jane; Davidson, Karina W.

    2013-01-01

    Objective: To examine gender differences in the association between beliefs in heart disease preventability and 10-year incidence of coronary heart disease (CHD) in a population-based sample. Methods: A total of 2,688 Noninstitutionalized Nova Scotians without prior CHD enrolled in the Nova Scotia Health Study (NSHS95) and were followed for 10…

  9. Characteristics of pregnant illicit drug users and associations between cannabis use and perinatal outcome in a population-based study.

    NARCIS (Netherlands)

    Gelder, M.M.H.J. van; Reefhuis, J.; Caton, A.R.; Werler, M.M.; Druschel, C.M.; Roeleveld, N.

    2010-01-01

    BACKGROUND: According to the 2004 National Survey on Drug Use and Health, 4.6% of American women reported use of an illicit drug during pregnancy. Previous studies on illicit drug use during pregnancy and perinatal outcomes showed inconsistent results. METHODS: This population-based study included

  10. DHLAS: A web-based information system for statistical genetic analysis of HLA population data.

    Science.gov (United States)

    Thriskos, P; Zintzaras, E; Germenis, A

    2007-03-01

    DHLAS (database HLA system) is a user-friendly, web-based information system for the analysis of human leukocyte antigens (HLA) data from population studies. DHLAS has been developed using JAVA and the R system, it runs on a Java Virtual Machine and its user-interface is web-based powered by the servlet engine TOMCAT. It utilizes STRUTS, a Model-View-Controller framework and uses several GNU packages to perform several of its tasks. The database engine it relies upon for fast access is MySQL, but others can be used a well. The system estimates metrics, performs statistical testing and produces graphs required for HLA population studies: (i) Hardy-Weinberg equilibrium (calculated using both asymptotic and exact tests), (ii) genetics distances (Euclidian or Nei), (iii) phylogenetic trees using the unweighted pair group method with averages and neigbor-joining method, (iv) linkage disequilibrium (pairwise and overall, including variance estimations), (v) haplotype frequencies (estimate using the expectation-maximization algorithm) and (vi) discriminant analysis. The main merit of DHLAS is the incorporation of a database, thus, the data can be stored and manipulated along with integrated genetic data analysis procedures. In addition, it has an open architecture allowing the inclusion of other functions and procedures.

  11. Moderate alcohol consumption may protect against overt autoimmune hypothyroidism: a population-based casecontrol study

    DEFF Research Database (Denmark)

    Carl, Allan; Pedersen, Inge Blow; Knudsen, Nils

    2012-01-01

    OBJECTIVE: Alcohol consumption is an important protective risk factor for many autoimmune diseases. We wished to study the association between alcohol consumption and autoimmune hypothyroidism. DESIGN: Population-based, case-control study, 1997-2001, Denmark. METHODS: Patients with newly diagnose......, or region of inhabitancy. CONCLUSIONS: Alcohol consumption seems to confer considerable protection against development of overt autoimmune hypothyroidism irrespective of sex and type of alcohol consumed.......OBJECTIVE: Alcohol consumption is an important protective risk factor for many autoimmune diseases. We wished to study the association between alcohol consumption and autoimmune hypothyroidism. DESIGN: Population-based, case-control study, 1997-2001, Denmark. METHODS: Patients with newly diagnosed...... of alcohol per week were as follows: 0 units/week, 1.98 (1.21-3.33); 11-20 units/week, 0.41 (0.20-0.83); and ≥21 units/week, 0.90 (0.41-2.00). Similar results were found for maximum previous alcohol consumption during a calendar year. No interaction was found with type of alcohol consumed (wine vs beer), sex...

  12. The implementation of DRG-based hospital reimbursement in Switzerland: A population-based perspective.

    Science.gov (United States)

    Busato, André; von Below, Georg

    2010-10-16

    Switzerland introduces a DRG (Diagnosis Related Groups) based system for hospital financing in 2012 in order to increase efficiency and transparency of Swiss health care. DRG-based hospital reimbursement is not simultaneously realized in all Swiss cantons and several cantons already implemented DRG-based financing irrespective of the national agenda, a setting that provides an opportunity to compare the situation in different cantons. Effects of introducing DRGs anticipated for providers and insurers are relatively well known but it remains less clear what effects DRGs will have on served populations. The objective of the study is therefore to analyze differences of volume and major quality indicators of care between areas with or without DRG-based hospital reimbursement from a population based perspective. Small area analysis of all hospitalizations in acute care hospitals and of all consultations reimbursed by mandatory basic health insurance for physicians in own practice during 2003-2007. The results show fewer hospitalizations and a relocation of resources to outpatient care in areas with DRG reimbursement. Overall burden of disease expressed as per capita DRG cost weights was almost identical between the two types of hospital reimbursement and no distinct temporal differences were detected in this respect. But the results show considerably higher 90-day rehospitalization rates in DRG areas. The study provides evidence of both desired and harmful effects related to the implementation of DRGs. Systematic monitoring of outcomes and quality of care are therefore essential elements to maintain in the Swiss health system after DRG's are implemented on a nationwide basis in 2012.

  13. Utilitarian prioritization of radiation oncology patients based on maximization of population tumour control

    Science.gov (United States)

    Ebert, M. A.; Li, W.; Jennings, L.; Kearvell, R.; Bydder, S.

    2013-06-01

    An objective method for establishing patient prioritization in the context of a radiotherapy waiting list is investigated. This is based on a utilitarian objective, being the greatest probability of local tumour control in the population of patients. A numerical simulation is developed and a clinical patient case-mix is used to determine the influence of the characteristics of the patient population on resulting optimal patient scheduling. With the utilitarian objective, large gains in tumour control probability (TCP) can be achieved for individuals or cohorts by prioritizing patients for that fraction of the patient population with relatively small sacrifices in TCP for a smaller fraction of the population. For a waiting list in steady state with five patients per day commencing treatment and leaving the list (and so with five patients per day entering the list), and a mean wait time of 35 days and a maximum of 90 days, optimized wait times ranged from a mean of one day for patients with tumour types with short effective doubling times to a mean of 66.9 days for prostate cancer patients. It is found that, when seeking the optimal daily order of patients on the waiting list in a constrained simulation, the relative rather than absolute value of TCP is the determinant of the resulting optimal waiting times. An increase in the mean waiting time mostly influences (increases) the optimal waiting times of patients with fast-growing tumours. The proportional representation of groups (separated by tumour type) in the patient population has an influence on the resulting distribution of optimal waiting times for patients in those groups, though has only a minor influence on the optimal mean waiting time for each group.

  14. Utilitarian prioritization of radiation oncology patients based on maximization of population tumour control

    International Nuclear Information System (INIS)

    Ebert, M A; Li, W; Kearvell, R; Bydder, S; Jennings, L

    2013-01-01

    An objective method for establishing patient prioritization in the context of a radiotherapy waiting list is investigated. This is based on a utilitarian objective, being the greatest probability of local tumour control in the population of patients. A numerical simulation is developed and a clinical patient case-mix is used to determine the influence of the characteristics of the patient population on resulting optimal patient scheduling. With the utilitarian objective, large gains in tumour control probability (TCP) can be achieved for individuals or cohorts by prioritizing patients for that fraction of the patient population with relatively small sacrifices in TCP for a smaller fraction of the population. For a waiting list in steady state with five patients per day commencing treatment and leaving the list (and so with five patients per day entering the list), and a mean wait time of 35 days and a maximum of 90 days, optimized wait times ranged from a mean of one day for patients with tumour types with short effective doubling times to a mean of 66.9 days for prostate cancer patients. It is found that, when seeking the optimal daily order of patients on the waiting list in a constrained simulation, the relative rather than absolute value of TCP is the determinant of the resulting optimal waiting times. An increase in the mean waiting time mostly influences (increases) the optimal waiting times of patients with fast-growing tumours. The proportional representation of groups (separated by tumour type) in the patient population has an influence on the resulting distribution of optimal waiting times for patients in those groups, though has only a minor influence on the optimal mean waiting time for each group. (paper)

  15. Risk of second primary colorectal cancer among colorectal cancer cases: A population-based analysis

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    Kavitha P Raj

    2011-01-01

    Full Text Available Background: Patients with history of colorectal cancer (CRC are at increased risk for developing a second primary colorectal cancer (SPCRC as compared to the general population. However, the degree of risk is uncertain. Here, we attempt to quantify the risk, using data from the large population-based California Cancer Registry (CCR. Materials and Methods: We analyzed the CCR data for cases with surgically-treated colon and rectal cancer diagnosed during the period 1990-2005 and followed through up to January 2008. We excluded those patients diagnosed with metastatic disease and those in whom SPCRC was diagnosed within 6 months of the diagnosis of the primary CRC. Standardized incidence ratios (SIR with 95% confidence intervals (CI were calculated to evaluate risk as compared to the underlying population after taking into account age, sex, ethnicity, and time at risk. Results: The study cohort consisted of 69809 cases with colon cancer and 34448 with rectal cancer. Among these patients there were 1443 cases of SPCRCs. The SIR for developing SPCRC was higher in colon cancer survivors (SIR=1.4; 95% CI: 1.3 to 1.5 as compared to the underlying population. The incidence of SPCRC was also higher in females (SIR=1.5; 95% CI: 1.3 to 1.6 and Hispanics (SIR=2.0; 95% CI: 1.7 to 2.4 with primary colon cancer. The SIR for developing an SPCRC was higher only among those whose initial tumor was located in the descending colon (SIR=1.6; 95% CI: 1.3 to 2.0 and proximal colon (SIR=1.4; 95% CI: 1.3 to 1.6. Conclusions: Our results confirm that CRC patients, especially females and Hispanics, are at a higher risk of developing SPCRC than the general population. Differential SPCRC risk by colorectal tumor subsite is dependent on gender and ethnicity, underscoring the heterogeneous nature of CRC.

  16. Temporal trend of carpal tunnel release surgery: a population-based time series analysis.

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    Naif Fnais

    Full Text Available BACKGROUND: Carpal tunnel release (CTR is among the most common hand surgeries, although little is known about its pattern. In this study, we aimed to investigate temporal trends, age and gender variation and current practice patterns in CTR surgeries. METHODS: We conducted a population-based time series analysis among over 13 million residents of Ontario, who underwent operative management for carpal tunnel syndrome (CTS from April 1, 1992 to March 31, 2010 using administrative claims data. RESULTS: The primary analysis revealed a fairly stable procedure rate of approximately 10 patients per 10,000 population per year receiving CTRs without any significant, consistent temporal trend (p = 0.94. Secondary analyses revealed different trends in procedure rates according to age. The annual procedure rate among those age >75 years increased from 22 per 10,000 population at the beginning of the study period to over 26 patients per 10,000 population (p<0.01 by the end of the study period. CTR surgical procedures were approximately two-fold more common among females relative to males (64.9% vs. 35.1 respectively; p<0.01. Lastly, CTR procedures are increasingly being conducted in the outpatient setting while procedures in the inpatient setting have been declining steadily - the proportion of procedures performed in the outpatient setting increased from 13% to over 30% by 2010 (p<0.01. CONCLUSION: Overall, CTR surgical-procedures are conducted at a rate of approximately 10 patients per 10,000 population annually with significant variation with respect to age and gender. CTR surgical procedures in ambulatory-care facilities may soon outpace procedure rates in the in-hospital setting.

  17. Hand Grip Strength: age and gender stratified normative data in a population-based study

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    Taylor Anne W

    2011-04-01

    Full Text Available Abstract Background The North West Adelaide Health Study is a representative longitudinal cohort study of people originally aged 18 years and over. The aim of this study was to describe normative data for hand grip strength in a community-based Australian population. Secondary aims were to investigate the relationship between body mass index (BMI and hand grip strength, and to compare Australian data with international hand grip strength norms. Methods The sample was randomly selected and recruited by telephone interview. Overall, 3 206 (81% of those recruited participants returned to the clinic during the second stage (2004-2006 which specifically focused on the collection of information relating to musculoskeletal conditions. Results Following the exclusion of 435 participants who had hand pain and/or arthritis, 1366 men and 1312 women participants provided hand grip strength measurement. The study population was relatively young, with 41.5% under 40 years; and their mean BMI was 28.1 kg/m2 (SD 5.5. Higher hand grip strength was weakly related to higher BMI in adults under the age of 30 and over the age of 70, but inversely related to higher BMI between these ages. Australian norms from this sample had amongst the lowest of the hand grip strength of the internationally published norms, except those from underweight populations. Conclusions This population demonstrated higher BMI and lower grip strength in younger participants than much of the international published, population data. A complete exploration of the relationship between BMI and hand grip strength was not fully explored as there were very few participants with BMI in the underweight range. The age and gender grip strength values are lower in younger adults than those reported in international literature.

  18. Use of Mobile Device Data To Better Estimate Dynamic Population Size for Wastewater-Based Epidemiology.

    Science.gov (United States)

    Thomas, Kevin V; Amador, Arturo; Baz-Lomba, Jose Antonio; Reid, Malcolm

    2017-10-03

    Wastewater-based epidemiology is an established approach for quantifying community drug use and has recently been applied to estimate population exposure to contaminants such as pesticides and phthalate plasticizers. A major source of uncertainty in the population weighted biomarker loads generated is related to estimating the number of people present in a sewer catchment at the time of sample collection. Here, the population quantified from mobile device-based population activity patterns was used to provide dynamic population normalized loads of illicit drugs and pharmaceuticals during a known period of high net fluctuation in the catchment population. Mobile device-based population activity patterns have for the first time quantified the high degree of intraday, week, and month variability within a specific sewer catchment. Dynamic population normalization showed that per capita pharmaceutical use remained unchanged during the period when static normalization would have indicated an average reduction of up to 31%. Per capita illicit drug use increased significantly during the monitoring period, an observation that was only possible to measure using dynamic population normalization. The study quantitatively confirms previous assessments that population estimates can account for uncertainties of up to 55% in static normalized data. Mobile device-based population activity patterns allow for dynamic normalization that yields much improved temporal and spatial trend analysis.

  19. portfolio optimization based on nonparametric estimation methods

    Directory of Open Access Journals (Sweden)

    mahsa ghandehari

    2017-03-01

    Full Text Available One of the major issues investors are facing with in capital markets is decision making about select an appropriate stock exchange for investing and selecting an optimal portfolio. This process is done through the risk and expected return assessment. On the other hand in portfolio selection problem if the assets expected returns are normally distributed, variance and standard deviation are used as a risk measure. But, the expected returns on assets are not necessarily normal and sometimes have dramatic differences from normal distribution. This paper with the introduction of conditional value at risk ( CVaR, as a measure of risk in a nonparametric framework, for a given expected return, offers the optimal portfolio and this method is compared with the linear programming method. The data used in this study consists of monthly returns of 15 companies selected from the top 50 companies in Tehran Stock Exchange during the winter of 1392 which is considered from April of 1388 to June of 1393. The results of this study show the superiority of nonparametric method over the linear programming method and the nonparametric method is much faster than the linear programming method.

  20. Unilateral Vocal Fold Paralysis and Risk of Pneumonia: A Nationwide Population-Based Cohort Study.

    Science.gov (United States)

    Tsai, Ming-Shao; Yang, Yao-Hsu; Liu, Chia-Yen; Lin, Meng-Hung; Chang, Geng-He; Tsai, Yao-Te; Li, Hsueh-Yu; Tsai, Ying-Huang; Hsu, Cheng-Ming

    2018-05-01

    Objective To investigate pneumonia risk among patients with unilateral vocal fold paralysis (UVFP). Study Design Retrospective population-based cohort study. Setting This study used data from the National Health Insurance Research Database of Taiwan, a nationwide population-based database. Subjects and Methods A total of 419 patients newly diagnosed with UVFP between January 1, 1997, and December 31, 2013, were identified from the Longitudinal Health Insurance Database 2000, a nationally representative database of 1 million randomly selected patients. Moreover, 1676 patients without UVFP were matched to patients with UVFP at a 1:4 ratio based on age, sex, socioeconomic status, urbanization level, and site-specific cancers. Patients were followed up until death or the end of the study period (December 31, 2013). The primary outcome was the occurrence of pneumonia. Results The cumulative incidence of pneumonia was significantly higher for patients with UVFP than those without UFVP ( P < .001). The adjusted Cox proportional hazard model showed that UVFP was significantly associated with a higher incidence of pneumonia (hazard ratio, 1.97; 95% CI, 1.35-2.86; P < .001). Subgroup analyses demonstrated that UVFP was an independent risk factor of pneumonia for 4 subgroups: young (18-50 years), older (≥51 years), male, and cancer. Conclusion This is the first nationwide population-based cohort study to investigate the association between UVFP and pneumonia. The findings indicate that UVFP is an independent risk factor of pneumonia. Given the study results, physicians should be aware of the potential for pneumonia occurrence following UVFP.

  1. Epidemiology of benign paroxysmal positional vertigo: a population based study.

    Science.gov (United States)

    von Brevern, M; Radtke, A; Lezius, F; Feldmann, M; Ziese, T; Lempert, T; Neuhauser, H

    2007-07-01

    To examine the prevalence and incidence, clinical presentation, societal impact and comorbid conditions of benign paroxysmal positional vertigo (BPPV) in the general population. Cross-sectional, nationally representative neurotological survey of the general adult population in Germany with a two stage sampling design: screening of 4869 participants from the German National Telephone Health Interview Survey 2003 (response rate 52%) for moderate or severe dizziness or vertigo, followed by validated neurotological interviews (n = 1003; response rate 87%). Diagnostic criteria for BPPV were at least five attacks of vestibular vertigo lasting vertigo. The lifetime prevalence of BPPV was 2.4%, the 1 year prevalence was 1.6% and the 1 year incidence was 0.6%. The median duration of an episode was 2 weeks. In 86% of affected individuals, BPPV led to medical consultation, interruption of daily activities or sick leave. In total, only 8% of affected participants received effective treatment. On multivariate analysis, age, migraine, hypertension, hyperlipidaemia and stroke were independently associated with BPPV. BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact and medical costs.

  2. Incidence of anogenital warts in Germany: a population-based cohort study

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    Mikolajczyk Rafael T

    2010-12-01

    Full Text Available Abstract Background Human papilloma virus (HPV types 6 and 11 account for 90 percent of anogenital warts (AGW. Assessment of a potential reduction of the incidence of AGW following introduction of HPV vaccines requires population-based incidence rates. The aim of this study was to estimate incidence rates of AGW in Germany, stratified by age, sex, and region. Additionally, the medical practitioner (gynaecologist, dermatologist, urologist etc. who made the initial diagnosis of AGW was assessed. Methods Retrospective cohort study in a population aged 10 to 79 years in a population-based healthcare insurance database. The database included more than 14 million insurance members from all over Germany during the years 2004-2006. A case of AGW was considered incident if a disease-free period of twelve months preceded the diagnosis. To assess regional variation, analyses were performed by federal state. Results The estimated incidence rate was 169.5/100,000 person-years for the German population aged 10 to 79 years. Most cases occurred in the 15 to 40 years age group. The incidence rate was higher and showed a peak at younger ages in females than in males. The highest incidence rates for both sexes were observed in the city-states Berlin, Hamburg and Bremen. In females, initial diagnosis of AGW was most frequently made by a gynaecologist (71.7%, whereas in males, AGW were most frequently diagnosed by a dermatologist (44.8% or urologist (25.1%. Conclusions Incidence of AGW in Germany is comparable with findings for other countries. As expected, most cases occurred in the younger age groups. The frequency of diagnoses of AGW differs between sexes and women and men receive treatment by doctors of different specialties.

  3. Value of information methods to design a clinical trial in a small population to optimise a health economic utility function

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    Michael Pearce

    2018-02-01

    Full Text Available Abstract Background Most confirmatory randomised controlled clinical trials (RCTs are designed with specified power, usually 80% or 90%, for a hypothesis test conducted at a given significance level, usually 2.5% for a one-sided test. Approval of the experimental treatment by regulatory agencies is then based on the result of such a significance test with other information to balance the risk of adverse events against the benefit of the treatment to future patients. In the setting of a rare disease, recruiting sufficient patients to achieve conventional error rates for clinically reasonable effect sizes may be infeasible, suggesting that the decision-making process should reflect the size of the target population. Methods We considered the use of a decision-theoretic value of information (VOI method to obtain the optimal sample size and significance level for confirmatory RCTs in a range of settings. We assume the decision maker represents society. For simplicity we assume the primary endpoint to be normally distributed with unknown mean following some normal prior distribution representing information on the anticipated effectiveness of the therapy available before the trial. The method is illustrated by an application in an RCT in haemophilia A. We explicitly specify the utility in terms of improvement in primary outcome and compare this with the costs of treating patients, both financial and in terms of potential harm, during the trial and in the future. Results The optimal sample size for the clinical trial decreases as the size of the population decreases. For non-zero cost of treating future patients, either monetary or in terms of potential harmful effects, stronger evidence is required for approval as the population size increases, though this is not the case if the costs of treating future patients are ignored. Conclusions Decision-theoretic VOI methods offer a flexible approach with both type I error rate and power (or equivalently

  4. Improved method for calculation of population doses from nuclear complexes over large geographical areas

    International Nuclear Information System (INIS)

    Corley, J.P.; Baker, D.A.; Hill, E.R.; Wendell, L.L.

    1977-09-01

    To simplify the calculation of potential long-distance environmental impacts, an overall average population exposure coefficient (P.E.C.) for the entire contiguous United States was calculated for releases to the atmosphere from Hanford facilities. The method, requiring machine computation, combines Bureau of Census population data by census enumeration district and an annual average atmospheric dilution factor (anti chi/Q') derived from 12-hourly gridded wind analyses provided by the NOAA's National Meteorological Center. A variable-trajectory puff-advection model was used to calculate an hourly anti chi/Q' for each grid square, assuming uniform hourly releases; seasonal and annual averages were then calculated. For Hanford, using 1970 census data, a P.E.C. of 2 x 10 -3 man-seconds per cubic meter was calculated. The P.E.C. is useful for both radioactive and nonradioactive releases. To calculate population doses for the entire contiguous United States, the P.E.C. is multiplied by the annual average release rate and then by the dose factor (rem/yr per Ci/m 3 ) for each radionuclide, and the dose contribution in man-rem is summed for all radionuclides. For multiple pathways, the P.E.C. is still useful, provided that doses from a unit release can be obtained from a set of atmospheric dose factors. The methodology is applicable to any point source, any set of population data by map grid coordinates, and any geographical area covered by equivalent meteorological data

  5. A window-based time series feature extraction method.

    Science.gov (United States)

    Katircioglu-Öztürk, Deniz; Güvenir, H Altay; Ravens, Ursula; Baykal, Nazife

    2017-10-01

    This study proposes a robust similarity score-based time series feature extraction method that is termed as Window-based Time series Feature ExtraCtion (WTC). Specifically, WTC generates domain-interpretable results and involves significantly low computational complexity thereby rendering itself useful for densely sampled and populated time series datasets. In this study, WTC is applied to a proprietary action potential (AP) time series dataset on human cardiomyocytes and three precordial leads from a publicly available electrocardiogram (ECG) dataset. This is followed by comparing WTC in terms of predictive accuracy and computational complexity with shapelet transform and fast shapelet transform (which constitutes an accelerated variant of the shapelet transform). The results indicate that WTC achieves a slightly higher classification performance with significantly lower execution time when compared to its shapelet-based alternatives. With respect to its interpretable features, WTC has a potential to enable medical experts to explore definitive common trends in novel datasets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Variables associated with olfactory disorders in adults: A U.S. population-based analysis

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    Julia Noel

    2017-03-01

    Full Text Available Objective: Olfactory dysfunction is known to have significant social, psychological, and safety implications. Despite increasingly recognized prevalence, potential risk factors for olfactory loss have been arbitrarily documented and knowledge is limited in scale. The aim of this study is to identify potential demographic and exposure variables correlating with olfactory dysfunction. Methods: Cross-sectional analysis of the 2011–2012 and 2013–2014 editions of the National Health Examination and Nutrition Survey was performed. The utilized survey reports from a nationally representative sample of about 5000 persons each year located in counties across the United States. There is an interview and physical examination component which includes demographic, socioeconomic, dietary, and health-related questions as well as medical, dental, physiologic measurements, and laboratory tests. 3594 adult respondents from 2011 to 2012 and 3708 respondents from 2013 to 2014 were identified from the above population-based database. The frequency of self-reported disorders as well as performance on odor identification testing was determined in relation to demographic factors, occupational or environmental exposures, and urinary levels of environmental and industrial compounds. Results: In both subjective and objective analysis, smell disorders were significantly more common with increasing age. While the non-Hispanic Black and non-Hispanic Asian populations were less likely to report subjective olfactory loss, they, along with Hispanics, performed more poorly on odor identification than Caucasians. Those with limited education had a decreased prevalence of hyposmia. Women outperformed men on smell testing. Those reporting exposure to vapors were more likely to experience olfactory dysfunction, and urinary levels of manganese, 2-Thioxothiazolidine-4-carboxylic acid, and 2-Aminothiazoline-4-carboxylic acid were lower among respondents with subjective smell

  7. Asthma exacerbation and proximity of residence to major roads: a population-based matched case-control study among the pediatric Medicaid population in Detroit, Michigan

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    Wahl Robert

    2011-04-01

    Full Text Available Abstract Background The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes using polychotomous conditional logistic regression. Results Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99 for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained

  8. Asthma exacerbation and proximity of residence to major roads: a population-based matched case-control study among the pediatric Medicaid population in Detroit, Michigan

    Science.gov (United States)

    2011-01-01

    Background The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthma-related events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression. Results Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population-based

  9. Low frequency of defective mismatch repair in a population-based series of upper urothelial carcinoma

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    Isfoss Björn L

    2005-03-01

    Full Text Available Abstract Background Upper urothelial cancer (UUC, i.e. transitional cell carcinomas of the renal pelvis and the ureter, occur at an increased frequency in patients with hereditary nonpolyposis colorectal cancer (HNPCC. Defective mismatch repair (MMR specifically characterizes HNPCC-associated tumors, but also occurs in subsets of some sporadic tumors, e.g. in gastrointestinal cancer and endometrial cancer. Methods We assessed the contribution of defective MMR to the development of UUC in a population-based series from the southern Swedish Cancer Registry, through microsatellite instability (MSI analysis and immunohistochemical evaluation of expression of the MMR proteins MLH1, PMS2, MSH2, and MSH6. Results A MSI-high phenotype was identified in 9/216 (4% successfully analyzed patients and a MSI-low phenotype in 5/216 (2%. Loss of MMR protein immunostaining was found in 11/216 (5% tumors, and affected most commonly MSH2 and MSH6. Conclusion This population-based series indicates that somatic MMR inactivation is a minor pathway in the development of UUC, but tumors that display defective MMR are, based on the immunohistochemical expression pattern, likely to be associated with HNPCC.

  10. Survival rate of breast cancer patients in Malaysia: a population-based study.

    Science.gov (United States)

    Abdullah, Nor Aini; Wan Mahiyuddin, Wan Rozita; Muhammad, Nor Asiah; Ali, Zainudin Mohamad; Ibrahim, Lailanor; Ibrahim Tamim, Nor Saleha; Mustafa, Amal Nasir; Kamaluddin, Muhammad Amir

    2013-01-01

    Breast cancer is the most common cancer among Malaysian women. Other than hospital-based results, there are no documented population-based survival rates of Malaysian women for breast cancers. This population- based retrospective cohort study was therefore conducted. Data were obtained from Health Informatics Centre, Ministry of Health Malaysia, National Cancer Registry and National Registration Department for the period from 1st Jan 2000 to 31st December 2005. Cases were captured by ICD-10 and linked to death certificates to identify the status. Only complete data were analysed. Survival time was calculated from the estimated date of diagnosis to the date of death or date of loss to follow-up. Observed survival rates were estimated by Kaplan- Meier method using SPSS Statistical Software version 17. A total of 10,230 complete data sets were analysed. The mean age at diagnosis was 50.6 years old. The overall 5-year survival rate was 49% with median survival time of 68.1 months. Indian women had a higher survival rate of 54% compared to Chinese women (49%) and Malays (45%). The overall 5-year survival rate of breast cancer patient among Malaysian women was still low for the cohort of 2000 to 2005 as compared to survival rates in developed nations. Therefore, it is necessary to enhance the strategies for early detection and intervention.

  11. Topology-Based Methods in Visualization 2015

    CERN Document Server

    Garth, Christoph; Weinkauf, Tino

    2017-01-01

    This book presents contributions on topics ranging from novel applications of topological analysis for particular problems, through studies of the effectiveness of modern topological methods, algorithmic improvements on existing methods, and parallel computation of topological structures, all the way to mathematical topologies not previously applied to data analysis. Topological methods are broadly recognized as valuable tools for analyzing the ever-increasing flood of data generated by simulation or acquisition. This is particularly the case in scientific visualization, where the data sets have long since surpassed the ability of the human mind to absorb every single byte of data. The biannual TopoInVis workshop has supported researchers in this area for a decade, and continues to serve as a vital forum for the presentation and discussion of novel results in applications in the area, creating a platform to disseminate knowledge about such implementations throughout and beyond the community. The present volum...

  12. Extension of landscape-based population viability models to ecoregional scales for conservation planning

    Science.gov (United States)

    Thomas W. Bonnot; Frank R. III Thompson; Joshua Millspaugh

    2011-01-01

    Landscape-based population models are potentially valuable tools in facilitating conservation planning and actions at large scales. However, such models have rarely been applied at ecoregional scales. We extended landscape-based population models to ecoregional scales for three species of concern in the Central Hardwoods Bird Conservation Region and compared model...

  13. Development of a Late-Life Dementia Prediction Index with Supervised Machine Learning in the Population-Based CAIDE Study.

    Science.gov (United States)

    Pekkala, Timo; Hall, Anette; Lötjönen, Jyrki; Mattila, Jussi; Soininen, Hilkka; Ngandu, Tiia; Laatikainen, Tiina; Kivipelto, Miia; Solomon, Alina

    2017-01-01

    This study aimed to develop a late-life dementia prediction model using a novel validated supervised machine learning method, the Disease State Index (DSI), in the Finnish population-based CAIDE study. The CAIDE study was based on previous population-based midlife surveys. CAIDE participants were re-examined twice in late-life, and the first late-life re-examination was used as baseline for the present study. The main study population included 709 cognitively normal subjects at first re-examination who returned to the second re-examination up to 10 years later (incident dementia n = 39). An extended population (n = 1009, incident dementia 151) included non-participants/non-survivors (national registers data). DSI was used to develop a dementia index based on first re-examination assessments. Performance in predicting dementia was assessed as area under the ROC curve (AUC). AUCs for DSI were 0.79 and 0.75 for main and extended populations. Included predictors were cognition, vascular factors, age, subjective memory complaints, and APOE genotype. The supervised machine learning method performed well in identifying comprehensive profiles for predicting dementia development up to 10 years later. DSI could thus be useful for identifying individuals who are most at risk and may benefit from dementia prevention interventions.

  14. Complementary methods to estimate population size of Antillean Manatees (Sirenia: Trichechidae at Cienaga de Paredes, Santander, Colombia

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    G.K. Arevalo-Gonzalez

    2014-06-01

    Full Text Available Information on manatee population size in Colombia is limited. This study was aimed at determining manatee population size in the Cienaga de Paredes (Colombia by three different methods: boat-based surveys, side-scan Sonar (SSS surveys and local interviews. Manatees were counted during breathing events by direct observation during the dry season, with the number of sightings per hour (NSH and maximum number of simultaneous sightings (MNSS used as occurrence indices. In 2002, we obtained an average NSH of 27.62 (SD=12.34 and the MNSS was 18; in 2010 the values were 55.71 (SD=29.79 and four respectively. Using linear-transect SSS data we estimated a population size of 12 individuals (%CV=27.3. The local community claimed that no hunting or entanglements had taken place in the area for over 20 years. These methods have pros and cons in terms of investment, effort, efficiency and community involvement, and their efficiency may vary in different seasons. Applying them in a complementary way and at greater spatial and temporal scales could enhance the accuracy of results.

  15. A Tomographic method based on genetic algorithms

    International Nuclear Information System (INIS)

    Turcanu, C.; Alecu, L.; Craciunescu, T.; Niculae, C.

    1997-01-01

    Computerized tomography being a non-destructive and non-evasive technique is frequently used in medical application to generate three dimensional images of objects. Genetic algorithms are efficient, domain independent for a large variety of problems. The proposed method produces good quality reconstructions even in case of very small number of projection angles. It requests no a priori knowledge about the solution and takes into account the statistical uncertainties. The main drawback of the method is the amount of computer memory and time needed. (author)

  16. Scope-Based Method Cache Analysis

    DEFF Research Database (Denmark)

    Huber, Benedikt; Hepp, Stefan; Schoeberl, Martin

    2014-01-01

    The quest for time-predictable systems has led to the exploration of new hardware architectures that simplify analysis and reasoning in the temporal domain, while still providing competitive performance. For the instruction memory, the method cache is a conceptually attractive solution, as it req......The quest for time-predictable systems has led to the exploration of new hardware architectures that simplify analysis and reasoning in the temporal domain, while still providing competitive performance. For the instruction memory, the method cache is a conceptually attractive solution...

  17. Valuing Convertible Bonds Based on LSRQM Method

    Directory of Open Access Journals (Sweden)

    Jian Liu

    2014-01-01

    Full Text Available Convertible bonds are one of the essential financial products for corporate finance, while the pricing theory is the key problem to the theoretical research of convertible bonds. This paper demonstrates how to price convertible bonds with call and put provisions using Least-Squares Randomized Quasi-Monte Carlo (LSRQM method. We consider the financial market with stochastic interest rates and credit risk and present a detailed description on calculating steps of convertible bonds value. The empirical results show that the model fits well the market prices of convertible bonds in China’s market and the LSRQM method is effective.

  18. Allogeneic blood transfusion and prognosis following total hip replacement: a population-based follow up study

    DEFF Research Database (Denmark)

    Pedersen, Alma B; Mehnert, Frank; Overgaard, Søren

    2009-01-01

    BACKGROUND: Allogeneic red blood cell transfusion is frequently used in total hip replacement surgery (THR). However, data on the prognosis of transfused patients are sparse. In this study we compared the risk of complications following THR in transfused and non-transfused patients. METHODS......: A population-based follow-up study was performed using data from medical databases in Denmark. We identified 28,087 primary THR procedures performed from 1999 to 2007, from which we computed a propensity score for red blood cell transfusion based on detailed data on patient-, procedure-, and hospital......-related characteristics. We were able to match 2,254 transfused with 2,254 non-transfused THR patients using the propensity score. RESULTS: Of the 28,087 THR patients, 9,063 (32.3%) received at least one red blood cell transfusion within 8 days of surgery. Transfused patients had higher 90-day mortality compared...

  19. Strategies to enhance participant recruitment and retention in research involving a community-based population.

    Science.gov (United States)

    McCullagh, Marjorie C; Sanon, Marie-Anne; Cohen, Michael A

    2014-11-01

    Challenges associated with recruiting and retaining community-based populations in research studies have been recognized yet remain of major concern for researchers. There is a need for exchange of recruitment and retention techniques that inform recruitment and retention strategies. Here, the authors discuss a variety of methods that were successful in exceeding target recruitment and retention goals in a randomized clinical trial of hearing protector use among farm operators. Recruitment and retention strategies were 1) based on a philosophy of mutually beneficial engagement in the research process, 2) culturally appropriate, 3) tailored to the unique needs of partnering agencies, and 4) developed and refined in a cyclical and iterative process. Sponsoring organizations are interested in cost-effective recruitment and retention strategies, particularly relating to culturally and ethnically diverse groups. These approaches may result in enhanced subject recruitment and retention, concomitant containment of study costs, and timely accomplishment of study aims. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Population-based metabolic syndrome risk score and its determinants: The Isfahan Healthy Heart Program

    Directory of Open Access Journals (Sweden)

    Mohsen Hosseini

    2014-01-01

    Full Text Available Background: Metabolic syndrome (MetSy, an important predisposing factor for the most of noncommunicable diseases, has become a global pandemic. Given different definitions used for the MetSy, recently using a score termed "continuous MetSy risk score (CMetSyS" is recommended. The aim of this study was to provide a CMetSyS in a population-based sample of Iranian adults and to assess its determinants. Materials and Methods: We used the data of the baseline survey of a community trial entitled "the Isfahan health heart program." The MetSy was defined according to the Revised National Cholesterol Education Program Third Adult Treatment Panel. All probable predictive models and their predictive performance were provided using leave-one-out cross-validated logistic regression and the receiver operation characteristic curve methods. Multiple linear regression was performed to assess factors associated with the CMetSyS. Results: The study population consisted of 8313 persons (49.9% male, mean age 38.54 ± 15.86 years. The MetSy was documented in 1539 persons (21.86%. Triglycerides and waist circumference were the best predictive components, and fasting plasma glucose had the lowest area under curve (AUC. The AUC for our best model was 95.36 (94.83-95.83%. The best predictive cutoff for this risk score was −1.151 with 89% sensitivity and 87.93% specificity. Conclusion: We provided four population-based leave-one-out cross-validated risk score models, with moderate to perfect predictive performance to identify the MetSy in Iranian adults. The CMetSyS had significant associations with high sensitive C-reactive protein, body mass index, leisure time, and workplace physical activity as well as age and gender.

  1. Genetic diversity of populations and clones of Rhopilema esculentum in China based on AFLP analysis

    Science.gov (United States)

    Qiao, Hongjin; Liu, Xiangquan; Zhang, Xijia; Jiang, Haibin; Wang, Jiying; Zhang, Limin

    2013-03-01

    Amplified fragment length polymorphisms (AFLP) markers were developed to assess the genetic variation of populations and clones of Rhopilema esculentum Kishinouye (Scyphozoa, Rhizostomatidae). One hundred and seventy-nine loci from 56 individuals of two hatchery populations and two wild populations were genotyped with five primer combinations. The polymorphic ratio, Shannon's diversity index and average heterozygosity were 70.3%, 0.346 and 0.228 for the white hatchery population, 74.3%, 0.313, and 0.201 for the red hatchery population, 79.3%, 0.349, and 0.224 for the Jiangsu wild population, and 74.9%, 0.328 and 0.210 for the Penglai wild population, respectively. Thus, all populations had a relatively high level of genetic diversity. A specific band was identified that could separate the white from the red hatchery population. There was 84.85% genetic differentiation within populations. Individual cluster analysis using unweighted pair-group method with arithmetic mean (UPGMA) suggested that hatchery populations and wild populations could be divided. For the hatchery populations, the white and red populations clustered separately; however, for the wild populations, Penglai and Jiangsu populations clustered together. The genetic diversity at the clone level was also determined. Our data suggest that there are relatively high genetic diversities within populations but low genetic differentiation between populations, which may be related to the long-term use of germplasm resources from Jiangsu Province for artificial seeding and releasing. These findings will benefit the artificial seeding and conservation of the germplasm resources.

  2. Evidence for Association of the E23K Variant of KCNJ11 Gene with Type 2 Diabetes in Tunisian Population: Population-Based Study and Meta-Analysis

    Science.gov (United States)

    Lasram, Khaled; Ben Halim, Nizar; Hsouna, Sana; Kefi, Rym; Arfa, Imen; Ghazouani, Welid; Jamoussi, Henda; Benrahma, Houda; Kharrat, Najla; Rebai, Ahmed; Ben Ammar, Slim; Bahri, Sonia; Barakat, Abdelhamid; Abid, Abdelmajid; Abdelhak, Sonia

    2014-01-01

    Aims. Genetic association studies have reported the E23K variant of KCNJ11 gene to be associated with Type 2 diabetes. In Arab populations, only four studies have investigated the role of this variant. We aimed to replicate and validate the association between the E23K variant and Type 2 diabetes in Tunisian and Arab populations. Methods. We have performed a case-control association study including 250 Tunisian patients with Type 2 diabetes and 267 controls. Allelic association has also been evaluated by 2 meta-analyses including all population-based studies among Tunisians and Arabs (2 and 5 populations, resp.). Results. A significant association between the E23K variant and Type 2 diabetes was found (OR = 1.6, 95% CI = 1.14–2.27, and P = 0.007). Furthermore, our meta-analysis has confirmed the significant role of the E23K variant in susceptibility of Type 2 diabetes in Tunisian and Arab populations (OR = 1.29, 95% CI = 1.15–1.46, and P < 10−3 and OR = 1.33, 95% CI = 1.13–1.56, and P = 0.001, resp.). Conclusion. Both case-control and meta-analyses results revealed the significant association between the E23K variant of KCNJ11 and Type 2 diabetes among Tunisians and Arabs. PMID:25165692

  3. Evidence for Association of the E23K Variant of KCNJ11 Gene with Type 2 Diabetes in Tunisian Population: Population-Based Study and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Khaled Lasram

    2014-01-01

    Full Text Available Aims. Genetic association studies have reported the E23K variant of KCNJ11 gene to be associated with Type 2 diabetes. In Arab populations, only four studies have investigated the role of this variant. We aimed to replicate and validate the association between the E23K variant and Type 2 diabetes in Tunisian and Arab populations. Methods. We have performed a case-control association study including 250 Tunisian patients with Type 2 diabetes and 267 controls. Allelic association has also been evaluated by 2 meta-analyses including all population-based studies among Tunisians and Arabs (2 and 5 populations, resp.. Results. A significant association between the E23K variant and Type 2 diabetes was found (OR = 1.6, 95% CI = 1.14–2.27, and P=0.007. Furthermore, our meta-analysis has confirmed the significant role of the E23K variant in susceptibility of Type 2 diabetes in Tunisian and Arab populations (OR = 1.29, 95% CI = 1.15–1.46, and P<10-3 and OR = 1.33, 95% CI = 1.13–1.56, and P=0.001, resp.. Conclusion. Both case-control and meta-analyses results revealed the significant association between the E23K variant of KCNJ11 and Type 2 diabetes among Tunisians and Arabs.

  4. Population-based imaging biobanks as source of big data.

    Science.gov (United States)

    Gatidis, Sergios; Heber, Sophia D; Storz, Corinna; Bamberg, Fabian

    2017-06-01

    Advances of computational sciences over the last decades have enabled the introduction of novel methodological approaches in biomedical research. Acquiring extensive and comprehensive data about a research subject and subsequently extracting significant information has opened new possibilities in gaining insight into biological and medical processes. This so-called big data approach has recently found entrance into medical imaging and numerous epidemiological studies have been implementing advanced imaging to identify imaging biomarkers that provide information about physiological processes, including normal development and aging but also on the development of pathological disease states. The purpose of this article is to present existing epidemiological imaging studies and to discuss opportunities, methodological and organizational aspects, and challenges that population imaging poses to the field of big data research.

  5. HMM-Based Gene Annotation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Haussler, David; Hughey, Richard; Karplus, Keven

    1999-09-20

    Development of new statistical methods and computational tools to identify genes in human genomic DNA, and to provide clues to their functions by identifying features such as transcription factor binding sites, tissue, specific expression and splicing patterns, and remove homologies at the protein level with genes of known function.

  6. A new method based on PAVAN

    International Nuclear Information System (INIS)

    Ding Sizhong; Jiang Haoyu

    2010-01-01

    In order to get more precise results, this paper changed the input data of PAVAN from joint frequency to hourly meteorological data. Although the sample points of meteorological diffusion factor of this new method is more conservative than PAVAN's, the results of the short term meteorological diffusion factor is not necessarily more conservative than PAVAN. (authors)

  7. Designs and Methods for Association Studies and Population Size Inference in Statistical Genetics

    DEFF Research Database (Denmark)

    Waltoft, Berit Lindum

    method provides a simple goodness of t test by comparing the observed SFS with the expected SFS under a given model of population size changes. By the use of Monte Carlo estimation the expected time between coalescent events can be estimated and the expected SFS can thereby be evaluated. Using......). The OR is interpreted as the eect of an exposure on the probability of being diseased at the end of follow-up, while the interpretation of the IRR is the eect of an exposure on the probability of becoming diseased. Through a simulation study, the OR from a classical case-control study is shown to be an inconsistent...... the classical chi-square statistics we are able to infer single parameter models. Multiple parameter models, e.g. multiple epochs, are harder to identify. By introducing the inference of population size back in time as an inverse problem, the second procedure applies the theory of smoothing splines to infer...

  8. Population-based sexual behavior surveys in China: Liuzhou compared with other prefectural cities.

    Science.gov (United States)

    Huang, Yingying; Abler, Laurie; Pan, Suiming; Henderson, Gail E; Wang, Xin; Yao, Xingliang; Parish, William L

    2014-02-01

    Sexual behaviors in China are rapidly changing; simultaneously, sexually transmitted infections (STI)/HIV prevalence is increasing in the general population. To investigate these major shifts, we examined sexual behaviors and self-reported STI in one prefectural city in southern China, Liuzhou, and compared it to other prefectural cities throughout China. We used adults age 18-39 from two sets of population-based surveys that paralleled each other in both content and method. The first set was the Liuzhou survey conducted in 2008 (n = 398). The second set consisted of two national surveys collected in 2006 and 2010 (n = 2,186). Liuzhou respondents reported more active social and sexual behaviors than their national counterparts, including more socializing, dancing, drinking excessively, sexual activity among never married men and women, purchasing commercial sex among men, one-night stands among men, multiple sexual partnerships and self-reported STI among both men and women. Women in Liuzhou reported greater sexual risk behavior than their national counterparts, although overall they reported less than their male counterparts; they were also more likely to have had an abortion than women in other prefectural cities. Our findings provide a comprehensive overview of the sexual context of Liuzhou among the general population, which may help explain the greater STI/HIV prevalence in Liuzhou.

  9. A new approach on seismic mortality estimations based on average population density

    Science.gov (United States)

    Zhu, Xiaoxin; Sun, Baiqing; Jin, Zhanyong

    2016-12-01

    This study examines a new methodology to predict the final seismic mortality from earthquakes in China. Most studies established the association between mortality estimation and seismic intensity without considering the population density. In China, however, the data are not always available, especially when it comes to the very urgent relief situation in the disaster. And the population density varies greatly from region to region. This motivates the development of empirical models that use historical death data to provide the path to analyze the death tolls for earthquakes. The present paper employs the average population density to predict the final death tolls in earthquakes using a case-based reasoning model from realistic perspective. To validate the forecasting results, historical data from 18 large-scale earthquakes occurred in China are used to estimate the seismic morality of each case. And a typical earthquake case occurred in the northwest of Sichuan Province is employed to demonstrate the estimation of final death toll. The strength of this paper is that it provides scientific methods with overall forecast errors lower than 20 %, and opens the door for conducting final death forecasts with a qualitative and quantitative approach. Limitations and future research are also analyzed and discussed in the conclusion.

  10. Lifestyle Characteristics and Gastroesophageal Reflux Disease: A Population-Based Study in Albania

    Directory of Open Access Journals (Sweden)

    Lulzim Çela

    2013-01-01

    Full Text Available Aim. We aimed to assess the prevalence and lifestyle correlates of gastroesophageal reflux disease (GERD in the adult population of Albania, a Mediterranean country in Southeast Europe which has experienced major behavioral changes in the past two decades. Methods. A cross-sectional study, conducted in 2012, included a population-representative sample of 845 individuals (≥18 years residing in Tirana (345 men, mean age: ; 500 women, mean age: ; response rate: 84.5%. Assessment of GERD was based on Montreal definition. Covariates included socioeconomic characteristics, lifestyle factors, and body mass index. Logistic regression was used to assess the association of socioeconomic characteristics and lifestyle factors with GERD. Results. The overall prevalence of GERD was 11.9%. There were no significant sex differences, but a higher prevalence among the older participants. In fully adjusted models, there was a positive relationship of GERD with smoking, physical inactivity, fried food consumption, and obesity, but not so for alcohol intake and meat consumption. Conclusion. We obtained important evidence on the prevalence and lifestyle correlates of GERD in a Western Balkans' country. Smoking, physical inactivity, and obesity were strong “predictors” of GERD in this population. Findings from this study should be replicated in prospective studies in Albania and other transitional settings.

  11. Prevalence of metabolic syndrome in Central America: a cross-sectional population-based study

    Directory of Open Access Journals (Sweden)

    Roy A. Wong-McClure

    2015-09-01

    Full Text Available OBJECTIVE: To report the prevalence of metabolic syndrome (MetS as found by the Central American Diabetes Initiative (CAMDI study for five major Central American populations: Belize (national; Costa Rica (San José; Guatemala (Guatemala City; Honduras (Tegucigalpa; and Nicaragua (Managua. METHODS: Study data on 6 185 adults aged 20 years or older with anthropometric and laboratory determination of MetS from population-based surveys were analyzed. Overall, the survey response rate was 82.0%. MetS prevalence was determined according to criteria from the Adult Treatment Panel III of the National Cholesterol Education Program. The study's protocol was reviewed and approved by the bioethical committee of each country studied. RESULTS: The overall standardized prevalence of MetS in the Central American region was 30.3% (95% confidence interval (CI: 27.1-33.4. There was wide variability by gender and work conditions, with higher prevalence among females and unpaid workers. The standardized percentage of the population free of any component of MetS was lowest in Costa Rica (9.0%; CI: 6.5-11.4 and highest in Honduras (21.1%; CI: 16.4-25.9. CONCLUSIONS: Overall prevalence of MetS in Central America is high. Strengthening surveillance of chronic diseases and establishing effective programs for preventing cardiovascular diseases might reduce the risk of MetS in Central America.

  12. Arts-based Methods and Organizational Learning

    DEFF Research Database (Denmark)

    This thematic volume explores the relationship between the arts and learning in various educational contexts and across cultures, but with a focus on higher education and organizational learning. Arts-based interventions are at the heart of this volume, which addresses how they are conceived, des...

  13. DTI analysis methods : Voxel-based analysis

    NARCIS (Netherlands)

    Van Hecke, Wim; Leemans, Alexander; Emsell, Louise

    2016-01-01

    Voxel-based analysis (VBA) of diffusion tensor imaging (DTI) data permits the investigation of voxel-wise differences or changes in DTI metrics in every voxel of a brain dataset. It is applied primarily in the exploratory analysis of hypothesized group-level alterations in DTI parameters, as it does

  14. Injuries in Aleppo, Syria; first population-based estimates and characterization of predominant types

    Directory of Open Access Journals (Sweden)

    Maziak Wasim

    2006-03-01

    Full Text Available Abstract Background Despite the growing burden of injuries worldwide, Syria and many other Arab countries still lack population-based estimates of different types of injuries. This study aims toprovide first population-based estimates of major injuries in Syria and characterize groups at increased risk. Methods An interviewer-administered population-based survey of adults 18–65 years residing in Aleppo, Syria was conducted in 2004. The study sample involved 2038 household representatives in Aleppo (45.2% men, mean age 35.3 ± 12.1, response rate 86%. We inquired about participants self-reported injuries in the past year that required medical attention as well as injuries among their household members. When reported, injuries were further assessed according to type, place, and outcome. Results Overall, there was 153 self-reported injuries in the past year (77.3 per 1000 adult respondents, 93.1 per 1000 in men and 64.4 per 1000 in women, p = 0.02. Other than gender, injuries differed by age (the older age group being least affected, and place of occurrence, as men were more likely to sustain traffic injuries and be injured outside the home. Injuries were reported among 236 household members (21.0 per 1000, and were slightly more frequent in children than adults (22.0 per 1000 for children, and 19.7 per 1000 for adults, p = 0.2. Traffic injuries, falls, and poisoning (food were by far the most common types of injury experienced by participants as well as their household members. Falls and traffic injuries seem to have caused most morbidity for the injured, while burns, although not frequently reported, were associated with an unfavorable outcome in the majority of cases. Conclusion This information provides baseline information about the burden of different injuries in Syria, and the sociodemographic factors related to them.

  15. Predictors of fibromyalgia: a population-based twin cohort study

    OpenAIRE

    Markkula, Ritva A; Kalso, Eija A; Kaprio, Jaakko A

    2016-01-01

    Abstract Background Fibromyalgia (FM) is a pain syndrome, the mechanisms and predictors of which are still unclear. We have earlier validated a set of FM-symptom questions for detecting possible FM in an epidemiological survey and thereby identified a cluster with “possible FM”. This study explores prospectively predictors for membership of that FM-symptom cluster. Methods ...

  16. The protocols for the 10/66 dementia research group population-based research programme

    Directory of Open Access Journals (Sweden)

    Salas Aquiles

    2007-07-01

    Full Text Available Abstract Background Latin America, China and India are experiencing unprecedentedly rapid demographic ageing with an increasing number of people with dementia. The 10/66 Dementia Research Group's title refers to the 66% of people with dementia that live in developing countries and the less than one tenth of population-based research carried out in those settings. This paper describes the protocols for the 10/66 population-based and intervention studies that aim to redress this imbalance. Methods/design Cross-sectional comprehensive one phase surveys have been conducted of all residents aged 65 and over of geographically defined catchment areas in ten low and middle income countries (India, China, Nigeria, Cuba, Dominican Republic, Brazil, Venezuela, Mexico, Peru and Argentina, with a sample size of between 1000 and 3000 (generally 2000. Each of the studies uses the same core minimum data set with cross-culturally validated assessments (dementia diagnosis and subtypes, mental disorders, physical health, anthropometry, demographics, extensive non communicable disease risk factor questionnaires, disability/functioning, health service utilisation, care arrangements and caregiver strain. Nested within the population based studies is a randomised controlled trial of a caregiver intervention for people with dementia and their families (ISRCTN41039907; ISRCTN41062011; ISRCTN95135433; ISRCTN66355402; ISRCTN93378627; ISRCTN94921815. A follow up of 2.5 to 3.5 years will be conducted in 7 countries (China, Cuba, Dominican Republic, Venezuela, Mexico, Peru and Argentina to assess risk factors for incident dementia, stroke and all cause and cause-specific mortality; verbal autopsy will be used to identify causes of death. Discussion The 10/66 DRG baseline population-based studies are nearly complete. The incidence phase will be completed in 2009. All investigators are committed to establish an anonymised file sharing archive with monitored public access. Our

  17. Exposure to ambient air pollution and the incidence of dementia: A population-based cohort study.

    Science.gov (United States)

    Chen, Hong; Kwong, Jeffrey C; Copes, Ray; Hystad, Perry; van Donkelaar, Aaron; Tu, Karen; Brook, Jeffrey R; Goldberg, Mark S; Martin, Randall V; Murray, Brian J; Wilton, Andrew S; Kopp, Alexander; Burnett, Richard T

    2017-11-01

    Emerging studies have implicated air pollution in the neurodegenerative processes. Less is known about the influence of air pollution, especially at the relatively low levels, on developing dementia. We conducted a population-based cohort study in Ontario, Canada, where the concentrations of pollutants are among the lowest in the world, to assess whether air pollution exposure is associated with incident dementia. The study population comprised all Ontario residents who, on 1 April 2001, were 55-85years old, Canadian-born, and free of physician-diagnosed dementia (~2.1 million individuals). Follow-up extended until 2013. We used population-based health administrative databases with a validated algorithm to ascertain incident diagnosis of dementia as well as prevalent cases. Using satellite observations, land-use regression model, and an optimal interpolation method, we derived long-term average exposure to fine particulate matter (≤2.5μm in diameter) (PM 2.5 ), nitrogen dioxide (NO 2 ), and ozone (O 3 ), respectively at the subjects' historical residences based on a population-based registry. We used multilevel spatial random-effects Cox proportional hazards models, adjusting for individual and contextual factors, such as diabetes, brain injury, and neighborhood income. We conducted various sensitivity analyses, such as lagging exposure up to 10years and considering a negative control outcome for which no (or weaker) association with air pollution is expected. We identified 257,816 incident cases of dementia in 2001-2013. We found a positive association between PM 2.5 and dementia incidence, with a hazard ratio (HR) of 1.04 (95% confidence interval (CI): 1.03-1.05) for every interquartile-range increase in exposure to PM 2.5 . Similarly, NO 2 was associated with increased incidence of dementia (HR=1.10; 95% CI: 1.08-1.12). No association was found for O 3 . These associations were robust to all sensitivity analyses examined. These estimates translate to 6.1% of

  18. The TSH levels and risk of hypothyroidism: Results from a population based prospective cohort study in an Iranian adult's population.

    Science.gov (United States)

    Aminorroaya, Ashraf; Meamar, Rokhsareh; Amini, Massoud; Feizi, Awat; Nasri, Maryam; Tabatabaei, Azamosadat; Faghihimani, Elham

    2017-06-01

    The aim of current study was to assess the relationship between serum TSH levels and hypothyroidism risk in the euthyroid population. In a population-based cohort study, a total of 615 individuals with a normal baseline TSH, from of total population (n=2254) in 2006, were followed up for 6years. TSH, total T4, thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured. The relative risk (RR) and 95% confidence interval (95%CI) were calculated based on logistic regression. The Receiver Operating Characteristic (ROC) analysis along with area under the curve (AUC) was used to prediction of future hypothyroidism. TSH level in 2006 was a significant predictor for overt hypothyroidism, in the total population (RR=3.5) and female (RR=1.37) (all, P valuehypothyroidism from euthyroid. However, this cut off was not observed when we included only negative TPO and TgAbs people in 2006. The RR of hypothyroidism increased gradually when TSH level increased from 2.06-3.6mIU/L to >3.6mIU/L in the total population and both sexes. In women, the risk of overt hypothyroidism was significantly higher in subjects with TSH above 3.6 than those subject with THS levels≤2.05 [RR: (CI95 %), 20.57(2.-207.04), P valuehypothyroidism in future. However, it was not applicable for people with negative TPOAb and negative TgAb. Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  19. Value of information methods to design a clinical trial in a small population to optimise a health economic utility function.

    Science.gov (United States)

    Pearce, Michael; Hee, Siew Wan; Madan, Jason; Posch, Martin; Day, Simon; Miller, Frank; Zohar, Sarah; Stallard, Nigel

    2018-02-08

    Most confirmatory randomised controlled clinical trials (RCTs) are designed with specified power, usually 80% or 90%, for a hypothesis test conducted at a given significance level, usually 2.5% for a one-sided test. Approval of the experimental treatment by regulatory agencies is then based on the result of such a significance test with other information to balance the risk of adverse events against the benefit of the treatment to future patients. In the setting of a rare disease, recruiting sufficient patients to achieve conventional error rates for clinically reasonable effect sizes may be infeasible, suggesting that the decision-making process should reflect the size of the target population. We considered the use of a decision-theoretic value of information (VOI) method to obtain the optimal sample size and significance level for confirmatory RCTs in a range of settings. We assume the decision maker represents society. For simplicity we assume the primary endpoint to be normally distributed with unknown mean following some normal prior distribution representing information on the anticipated effectiveness of the therapy available before the trial. The method is illustrated by an application in an RCT in haemophilia A. We explicitly specify the utility in terms of improvement in primary outcome and compare this with the costs of treating patients, both financial and in terms of potential harm, during the trial and in the future. The optimal sample size for the clinical trial decreases as the size of the population decreases. For non-zero cost of treating future patients, either monetary or in terms of potential harmful effects, stronger evidence is required for approval as the population size increases, though this is not the case if the costs of treating future patients are ignored. Decision-theoretic VOI methods offer a flexible approach with both type I error rate and power (or equivalently trial sample size) depending on the size of the future population for

  20. Physical multimorbidity and loneliness: A population-based study.

    Directory of Open Access Journals (Sweden)

    Andrew Stickley

    Full Text Available Multimorbidity has been linked to a variety of negative outcomes although as yet, there has been little research on its association with loneliness. This study examined the association between physical multimorbidity (≥ 2 physical diseases and loneliness in the general population and its potential mediators. Data came from the Adult Psychiatric Morbidity Survey 2007 (N = 7403, aged ≥16 years. Information was obtained on 20 doctor diagnosed physical conditions that were present in the previous year. An item from the Social Functioning Questionnaire (SFQ was used to obtain information on loneliness. Multivariable logistic regression analysis was used to examine associations. An increasing number of physical diseases was associated with higher odds for loneliness. Compared to no physical diseases, the odds ratio (OR (95% confidence interval: CI for loneliness increased from 1.34 (1.13-1.59 to 2.82 (2.11-3.78 between one and ≥5 physical diseases. This association was particularly strong in the youngest age group (i.e. 16-44 years. The loneliness-physical multimorbidity association was significantly mediated by stressful life events (% mediated 11.1%-30.5%, anxiety (30.2%, and depression (15.4%. Physical multimorbidity is associated with increased odds for loneliness. Prospective research is now needed to further elucidate this association and the factors that underlie it.

  1. Physical multimorbidity and loneliness: A population-based study.

    Science.gov (United States)

    Stickley, Andrew; Koyanagi, Ai

    2018-01-01

    Multimorbidity has been linked to a variety of negative outcomes although as yet, there has been little research on its association with loneliness. This study examined the association between physical multimorbidity (≥ 2 physical diseases) and loneliness in the general population and its potential mediators. Data came from the Adult Psychiatric Morbidity Survey 2007 (N = 7403, aged ≥16 years). Information was obtained on 20 doctor diagnosed physical conditions that were present in the previous year. An item from the Social Functioning Questionnaire (SFQ) was used to obtain information on loneliness. Multivariable logistic regression analysis was used to examine associations. An increasing number of physical diseases was associated with higher odds for loneliness. Compared to no physical diseases, the odds ratio (OR) (95% confidence interval: CI) for loneliness increased from 1.34 (1.13-1.59) to 2.82 (2.11-3.78) between one and ≥5 physical diseases. This association was particularly strong in the youngest age group (i.e. 16-44 years). The loneliness-physical multimorbidity association was significantly mediated by stressful life events (% mediated 11.1%-30.5%), anxiety (30.2%), and depression (15.4%). Physical multimorbidity is associated with increased odds for loneliness. Prospective research is now needed to further elucidate this association and the factors that underlie it.

  2. Suicidal Decapitation by Hanging-A Population-based Study.

    Science.gov (United States)

    Byard, Roger W; Gilbert, John D

    2018-05-01

    A prospective study was undertaken at Forensic Science SA over a 15-year period from July 2002 to June 2017 for all cases of adult (>18 years) suicidal hangings with decapitation. A total of 1446 cases of suicidal hangings were identified from a general population of approximately 1.5 million (1206 males-age range 18-97 years, average 42.6; and 240 females-age range 18-96 years, average 40.1). Only three cases of decapitation were found, all from long-drop hangings; these consisted of three males (ages 32-55 years; average 45 years). Spinal transections had occurred between the first and second, second and third, and third and fourth cervical vertebrae, respectively. In this study, the number of suicidal hangings with decapitation represented only 0.2% of the total number of hangings. These events are therefore extremely rare, most likely due to most suicidal hangings occurring from relatively low levels in a domestic environment. © 2017 American Academy of Forensic Sciences.

  3. Factors affecting outdoor exposure in winter: population-based study

    Science.gov (United States)

    Mäkinen, Tiina M.; Raatikka, Veli-Pekka; Rytkönen, Mika; Jokelainen, Jari; Rintamäki, Hannu; Ruuhela, Reija; Näyhä, Simo; Hassi, Juhani

    2006-09-01

    The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study ( n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women.

  4. Birth order and mortality: a population-based cohort study.

    Science.gov (United States)

    Barclay, Kieron; Kolk, Martin

    2015-04-01

    This study uses Swedish population register data to investigate the relationship between birth order and mortality at ages 30 to 69 for Swedish cohorts born between 1938 and 1960, using a within-family comparison. The main analyses are conducted with discrete-time survival analysis using a within-family comparison, and the estimates are adjusted for age, mother's age at the time of birth, and cohort. Focusing on sibships ranging in size from two to six, we find that mortality risk in adulthood increases with later birth order. The results show that the relative effect of birth order is greater among women than among men. This pattern is consistent for all the major causes of death but is particularly pronounced for mortality attributable to cancers of the respiratory system and to external causes. Further analyses in which we adjust for adult socioeconomic status and adult educational attainment suggest that social pathways only mediate the relationship between birth order and mortality risk in adulthood to a limited degree.

  5. Coexistence of structured populations with size-based prey selection

    DEFF Research Database (Denmark)

    Hartvig, Martin; Andersen, Ken Haste

    2013-01-01

    Abstract Species with a large adult-offspring size ratio and a preferred predator–prey mass ratio undergo ontogenetic trophic niche shift(s) throughout life. Trophic interactions between such species vary throughout life, resulting in different species-level interaction motifs depending on the ma......Abstract Species with a large adult-offspring size ratio and a preferred predator–prey mass ratio undergo ontogenetic trophic niche shift(s) throughout life. Trophic interactions between such species vary throughout life, resulting in different species-level interaction motifs depending...... on the maximum adult sizes and population size distributions. We explore the assembly and potential for coexistence of small communities where all species experience ontogenetic trophic niche shifts. The life-history of each species is described by a physiologically structured model and species identity...... there is a large scope for coexistence of two species, the scope for coexistence of three species is limited and we conclude that further trait differentiation is required for coexistence of more species-rich size-structured communities....

  6. QTL mapping for combining ability in different population-based ...

    Indian Academy of Sciences (India)

    based NCII designs: a simulation study. Lanzhi Li, Congwei Sun, Yuan Chen, Zhijun Dai, Zhen Qu, Xingfei Zheng, Sibin Yu,. Tongmin Mou, Chenwu Xu and Zhongli Hu. J. Genet. 92, 529–543. Journal of Genetics, Vol. 92, No. 3, December 2013 ...

  7. Experiences of gender based violence among refugee populations ...

    African Journals Online (AJOL)

    ... and concealment that are associated with numerous capacity challenges in access and utilisation of the available services. The extreme conditions that refugees go through during displacement, flight and resettlement tend to exacerbate and sustain GBV. Keywords: Experiences, Gender Based Violence, Refugee Camps ...

  8. Using Mindfulness-Based Strengths Practices with Gifted Populations

    Science.gov (United States)

    Sharp, Jennifer E.; Niemiec, Ryan M.; Lawrence, Christopher

    2017-01-01

    Mindfulness and character strengths are synergistic tools that work together to cultivate well-being. Mindfulness-Based Strengths Practice (MBSP) combines the research and practice of these constructs to enhance well-being, meaning, and engagement. In this article, research supporting how mindfulness and character strengths may benefit the gifted…

  9. An agent-based computational model for tuberculosis spreading on age-structured populations

    Science.gov (United States)

    Graciani Rodrigues, C. C.; Espíndola, Aquino L.; Penna, T. J. P.

    2015-06-01

    In this work we present an agent-based computational model to study the spreading of the tuberculosis (TB) disease on age-structured populations. The model proposed is a merge of two previous models: an agent-based computational model for the spreading of tuberculosis and a bit-string model for biological aging. The combination of TB with the population aging, reproduces the coexistence of health states, as seen in real populations. In addition, the universal exponential behavior of mortalities curves is still preserved. Finally, the population distribution as function of age shows the prevalence of TB mostly in elders, for high efficacy treatments.

  10. Knowledge-based methods for control systems

    International Nuclear Information System (INIS)

    Larsson, J.E.

    1992-01-01

    This thesis consists of three projects which combine artificial intelligence and control. The first part describes an expert system interface for system identification, using the interactive identification program Idpac. The interface works as an intelligent help system, using the command spy strategy. It contains a multitude of help system ideas. The concept of scripts is introduced as a data structure used to describe the procedural part of the knowledge in the interface. Production rules are used to represent diagnostic knowledge. A small knowledge database of scripts and rules has been developed and an example run is shown. The second part describes an expert system for frequency response analysis. This is one of the oldest and most widely used methods to determine the dynamics of a stable linear system. Though quite simple, it requires knowledge and experience of the user, in order to produce reliable results. The expert system is designed to help the user in performing the analysis. It checks whether the system is linear, finds the frequency and amplitude ranges, verifies the results, and, if errors should occur, tries to give explanation and remedies for them. The third part describes three diagnostic methods for use with industrial processes. They are measurement validation, i.e., consistency checking of sensor and measurement values using any redundancy of instrumentation; alarm analysis, i.e. analysis of multiple alarm situations to find which alarms are directly connected to primary faults and which alarms are consequential effects of the primary ones; and fault diagnosis, i.e., a search for the causes of and remedies for faults. The three methods use multilevel flow models, (MFM), to describe the target process. They have been implemented in the programming tool G2, and successfully tested on two small processes. (164 refs.) (au)

  11. Population-based resequencing of experimentally evolved populations reveals the genetic basis of body size variation in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Thomas L Turner

    2011-03-01

    Full Text Available Body size is a classic quantitative trait with evolutionarily significant variation within many species. Locating the alleles responsible for this variation would help understand the maintenance of variation in body size in particular, as well as quantitative traits in general. However, successful genome-wide association of genotype and phenotype may require very large sample sizes if alleles have low population frequencies or modest effects. As a complementary approach, we propose that population-based resequencing of experimentally evolved populations allows for considerable power to map functional variation. Here, we use this technique to investigate the genetic basis of natural variation in body size in Drosophila melanogaster. Significant differentiation of hundreds of loci in replicate selection populations supports the hypothesis that the genetic basis of body size variation is very polygenic in D. melanogaster. Significantly differentiated variants are limited to single genes at some loci, allowing precise hypotheses to be formed regarding causal polymorphisms, while other significant regions are large and contain many genes. By using significantly associated polymorphisms as a priori candidates in follow-up studies, these data are expected to provide considerable power to determine the genetic basis of natural variation in body size.

  12. Model-based prediction of nephropathia epidemica outbreaks based on climatological and vegetation data and bank vole population dynamics.

    Science.gov (United States)

    Haredasht, S Amirpour; Taylor, C J; Maes, P; Verstraeten, W W; Clement, J; Barrios, M; Lagrou, K; Van Ranst, M; Coppin, P; Berckmans, D; Aerts, J-M

    2013-11-01

    Wildlife-originated zoonotic diseases in general are a major contributor to emerging infectious diseases. Hantaviruses more specifically cause thousands of human disease cases annually worldwide, while understanding and predicting human hantavirus epidemics pose numerous unsolved challenges. Nephropathia epidemica (NE) is a human infection caused by Puumala virus, which is naturally carried and shed by bank voles (Myodes glareolus). The objective of this study was to develop a method that allows model-based predicting 3 months ahead of the occurrence of NE epidemics. Two data sets were utilized to develop and test the models. These data sets were concerned with NE cases in Finland and Belgium. In this study, we selected the most relevant inputs from all the available data for use in a dynamic linear regression (DLR) model. The number of NE cases in Finland were modelled using data from 1996 to 2008. The NE cases were predicted based on the time series data of average monthly air temperature (°C) and bank voles' trapping index using a DLR model. The bank voles' trapping index data were interpolated using a related dynamic harmonic regression model (DHR). Here, the DLR and DHR models used time-varying parameters. Both the DHR and DLR models were based on a unified state-space estimation framework. For the Belgium case, no time series of the bank voles' population dynamics were available. Several studies, however, have suggested that the population of bank voles is related to the variation in seed production of beech and oak trees in Northern Europe. Therefore, the NE occurrence pattern in Belgium was predicted based on a DLR model by using remotely sensed phenology parameters of broad-leaved forests, together with the oak and beech seed categories and average monthly air temperature (°C) using data from 2001 to 2009. Our results suggest that even without any knowledge about hantavirus dynamics in the host population, the time variation in NE outbreaks in Finland

  13. Building a population-based diabetes register: an Italian experience.

    Science.gov (United States)

    Ballotari, Paola; Chiatamone Ranieri, Sofia; Vicentini, Massimo; Caroli, Stefania; Gardini, Andrea; Rodolfi, Rossella; Crucco, Roberto; Greci, Marina; Manicardi, Valeria; Giorgi Rossi, Paolo

    2014-01-01

    To describe the methodology used to set up the Reggio Emilia (northern Italy) Diabetes Register. The prevalence estimates on December 31st, 2009 are also provided. The Diabetes Register covers all residents in the Reggio Emilia province. The register was created by deterministic linkage of six routinely collected data sources through a definite algorithm able to ascertain cases and to distinguish type of diabetes and model of care: Hospital Discharge, Drug Dispensation, Biochemistry Laboratory, Disease-specific Exemption, Diabetes Outpatient Clinics, and Mortality databases. Using these data, we estimated crude prevalence on December 31st, 2009 by sex, age groups, and type of diabetes. There were 25,425 ascertained prevalent cases on December 31st, 2009. Drug Dispensation and Exemption databases made the greatest contribution to prevalence. Analyzing overlapping sources, more than 80% of cases were reported by at least two sources. Crude prevalence was 4.8% and 5.9% for the whole population and for people aged 18 years and over, respectively. Males accounted for 53.6%. Type 1 diabetes accounted for 3.8% of cases, while people with Type 2 diabetes were the overriding majority (91.2%), and Diabetes Outpatient Clinics treated 75.4% of people with Type 2 diabetes. The Register is able to quantify the burden of disease, the first step in planning, implementing, and monitoring appropriate interventions. All data sources contributed to completeness and/or accuracy of the Register. Although all cases are identified by deterministic record linkage, manual revision and General Practitioner involvement are still necessary when information is insufficient or conflicting. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. The incidence of inflammatory bowel disease in Northern China: a prospective population-based study.

    Directory of Open Access Journals (Sweden)

    Hong Yang

    Full Text Available AIMS & BACKGROUNDS: Although inflammatory bowel diseases (IBD are emerging and increasing in China, epidemiologic data are rarely available. This study was to investigate the epidemiological and clinical characteristics of IBD in Northern China. METHODS: This is a prospective, population-based study of incidence of IBD in Daqing, Heilongjiang province of Northern China from March 1, 2012 to February 28, 2013. All incident patients with IBD were clinically identified by IBD specialist group from five main General Hospitals covering the healthcare service for 1,343,364 residents in the urban areas of Daqing. IBD cases included in this study were followed-up for three months for diagnosis confirmation. RESULTS: A total of 27 new IBD cases including 25 cases of ulcerative colitis (UC and 2 cases of Crohn's disease (CD were identified. The population at risk was 1,343,364 person years. Age-adjusted incidence for total IBD, CD and UC were 1.77, 0.13, and 1.64 per 100,000 population, respectively. A male predominance was found in CD patients (male to female ratio was 2 ∶ 0. In contrast, no obvious gender predominance was found in UC patients (male to female ratio was 1 ∶ 1.1. CD patients were diagnosed at an average age of 39.5 years. The main disease phenotypes of UC were distal colitis with a 24% of proctitis and 56% of left-sided colitis. The mean diagnostic age of UC patients was 48.9 years. CONCLUSIONS: This is the first report on the incidence of IBD in the Northern Chinese population. A lower incidence of IBD, similar male predominance for CD, similar disease phenotype of UC, and lower disease activity was observed in Daqing compared to that in Southern China.

  15. Cigarette smoking, nicotine dependence and anxiety disorders: a systematic review of population-based, epidemiological studies

    Directory of Open Access Journals (Sweden)

    Moylan Steven

    2012-10-01

    Full Text Available Abstract Background Multiple studies have demonstrated that rates of smoking and nicotine dependence are increased in individuals with anxiety disorders. However, significant variability exists in the epidemiological literature exploring this relationship, including study design (cross-sectional versus prospective, the population assessed (random sample versus clinical population and diagnostic instrument utilized. Methods We undertook a systematic review of population-based observational studies that utilized recognized structured clinical diagnostic criteria (Diagnostic and Statistical Manual of Mental Disorders (DSM or International Classification of Diseases (ICD for anxiety disorder diagnosis to investigate the relationship between cigarette smoking, nicotine dependence and anxiety disorders. Results In total, 47 studies met the predefined inclusion criteria, with 12 studies providing prospective information and 5 studies providing quasiprospective information. The available evidence suggests that some baseline anxiety disorders are a risk factor for initiation of smoking and nicotine dependence, although the evidence is heterogeneous and many studies did not control for the effect of comorbid substance use disorders. The identified evidence however appeared to more consistently support cigarette smoking and nicotine dependence as being a risk factor for development of some anxiety disorders (for example, panic disorder, generalized anxiety disorder, although these findings were not replicated in all studies. A number of inconsistencies in the literature were identified. Conclusions Although many studies have demonstrated increased rates of smoking and nicotine dependence in individuals with anxiety disorders, there is a limited and heterogeneous literature that has prospectively examined this relationship in population studies using validated diagnostic criteria. The most consistent evidence supports smoking and nicotine dependence as

  16. Risk of Monozygotic Twins After Assisted Reproduction: A Population-Based Approach.

    Science.gov (United States)

    Parazzini, Fabio; Cipriani, Sonia; Bianchi, Stefano; Bulfoni, Camilla; Bortolus, Renata; Somigliana, Edgardo

    2016-02-01

    Recent studies have suggested that ovarian stimulation and assisted reproductive techniques (ART) may increase the frequency of monozygotic twins. In this article, we present the analysis of the estimated frequency of twin deliveries following in vitro fertilization (IVF) in Lombardy during the period 2010-2014 for a total of 450,949 pregnancies. This is a population-based study using data from the regional data base of Lombardy, a northern Italian region with a population of about 10 million inhabitants. During the considered period, a total of 461,424 single or multiple births were registered in Lombardy. After exclusion of triplets or more pregnancies, the total number of twin deliveries, in separate strata of like and unlike sex pregnancies twin deliveries, were obtained and the rate of twin deliveries was computed according to spontaneous and non-spontaneous conception and type of ART. Further, estimates of dizygotic or monozygotic twin births were calculated using Weinberg's methods. The frequency of twins deliveries was 1.24/100 deliveries after natural conception and 20.05 after assisted conception. The estimated rates of monozygotic twins was 0.45 and 0.72/100 (95% CI: 0.58-0.91) deliveries after natural and assisted conception, respectively. This difference was statistically significant (p assisted than after natural conception.

  17. Update of the Case Definitions for Population-Based Surveillance of Periodontitis

    Science.gov (United States)

    Eke, Paul I.; Page, Roy C.; Wei, Liang; Thornton-Evans, Gina; Genco, Robert J.

    2018-01-01

    Background This report adds a new definition for mild periodontitis that allows for better descriptions of the overall prevalence of periodontitis in populations. In 2007, the Centers for Disease Control and Prevention in partnership with the American Academy of Periodontology developed and reported standard case definitions for surveillance of moderate and severe periodontitis based on measurements of probing depth (PD) and clinical attachment loss (AL) at interproximal sites. However, combined cases of moderate and severe periodontitis are insufficient to determine the total prevalence of periodontitis in populations. Methods The authors proposed a definition for mild periodontitis as ≥2 interproximal sites with AL ≥3 mm and ≥2 interproximal sites with PD ≥4 mm (not on the same tooth) or one site with PD ≥5 mm. The effect of the proposed definition on the total burden of periodontitis was assessed in a convenience sample of 456 adults ≥35 years old and compared with other previously reported definitions for similar categories of periodontitis. Results Addition of mild periodontitis increases the total prevalence of periodontitis by ≈31% in this sample when compared with the prevalence of severe and moderate disease. Conclusion Total periodontitis using the case definitions in this study should be based on the sum of mild, moderate, and severe periodontitis. PMID:22420873

  18. The dynamic influence of human resources on evidence-based intervention sustainability and population outcomes: an agent-based modeling approach.

    Science.gov (United States)

    McKay, Virginia R; Hoffer, Lee D; Combs, Todd B; Margaret Dolcini, M

    2018-06-05

    Sustaining evidence-based interventions (EBIs) is an ongoing challenge for dissemination and implementation science in public health and social services. Characterizing the relationship among human resource capacity within an agency and subsequent population outcomes is an important step to improving our understanding of how EBIs are sustained. Although human resource capacity and population outcomes are theoretically related, examining them over time within real-world experiments is difficult. Simulation approaches, especially agent-based models, offer advantages that complement existing methods. We used an agent-based model to examine the relationships among human resources, EBI delivery, and population outcomes by simulating provision of an EBI through a hypothetical agency and its staff. We used data from existing studies examining a widely implemented HIV prevention intervention to inform simulation design, calibration, and validity. Once we developed a baseline model, we used the model as a simulated laboratory by systematically varying three human resource variables: the number of staff positions, the staff turnover rate, and timing in training. We tracked the subsequent influence on EBI delivery and the level of population risk over time to describe the overall and dynamic relationships among these variables. Higher overall levels of human resource capacity at an agency (more positions) led to more extensive EBI delivery over time and lowered population risk earlier in time. In simulations representing the typical human resource investments, substantial influences on population risk were visible after approximately 2 years and peaked around 4 years. Human resources, especially staff positions, have an important impact on EBI sustainability and ultimately population health. A minimum level of human resources based on the context (e.g., size of the initial population and characteristics of the EBI) is likely needed for an EBI to have a meaningful impact on

  19. Insomnia in Sweden: A Population-Based Survey

    OpenAIRE

    Mallon, Lena; Broman, Jan-Erik; Åkerstedt, Torbjörn; Hetta, Jerker

    2014-01-01

    Aims. Estimate the prevalence of insomnia and examine effects of sex, age, health problems, sleep duration, need for treatment, and usage of sleep medication. Methods. A sample of 1,550 subjects aged 18–84 years was selected for a telephone interview. The interview was completed by 1,128 subjects (72.8%). Results. 24.6% reported insomnia symptoms. Insomnia disorder, that is, insomnia symptoms and daytime consequences, was reported by 10.5%. The prevalence was similar among all age groups, wit...

  20. Disparities in pediatric leukemia early survival in Argentina: a population-based study

    Directory of Open Access Journals (Sweden)

    Gilda Garibotti

    2014-10-01

    Full Text Available OBJECTIVE: To identify disparities-using recursive partitioning (RP-in early survival for children with leukemias treated in Argentina, and to depict the main characteristics of the most vulnerable groups. METHODS: This secondary data analysis evaluated 12-month survival (12-ms in 3 987 children diagnosed between 2000 and 2008 with lymphoid leukemia (LL and myeloid leukemia (ML and registered in Argentina's population-based oncopediatric registry. Prognostic groups based on age at diagnosis, gender, socioeconomic index of the province of residence, and migration to a different province to receive health care were identified using the RP method. RESULTS: Overall 12-ms for LL and ML cases was 83.7% and 59.9% respectively. RP detected major gaps in 12-ms. Among 1-10-year-old LL patients from poorer provinces, 12-ms for those who did and did not migrate was 87.0% and 78.2% respectively. Survival of ML patients < 2 years old from provinces with a low/medium socioeconomic index was 38.9% compared to 62.1% for those in the same age group from richer provinces. For 2-14-year-old ML patients living in poor provinces, patient migration was associated with a 30% increase in 12-ms. CONCLUSIONS: Major disparities in leukemia survival among Argentine children were found. Patient migration and socioeconomic index of residence province were associated with survival. The RP method was instrumental in identifying and characterizing vulnerable groups.

  1. Prevalence of coronary artery disease and coronary risk factors in Kerala, South India: A population survey – Design and methods

    Directory of Open Access Journals (Sweden)

    Geevar Zachariah

    2013-05-01

    Methods: The design of the study was cross-sectional population survey. We estimated the sample size based on an anticipated prevalence of 7.4% of CAD for rural and 11% for urban Kerala. The derived sample sizes for rural and urban areas were 3000 and 2400, respectively. The urban areas for sampling constituted one ward each from three municipal corporations at different parts of the state. The rural sample was drawn from two panchayats each in the same districts as the urban sample. One adult from each household in the age group of 20–59 years was selected using Kish method. All subjects between 60 and 79 years were included from each household. A detailed questionnaire was administered to assess the risk factors, history of CAD, family history, educational status, socioeconomic status, dietary habits, physical activity and treatment for CAD; anthropometric measurements, blood pressure, electrocardiogram and fasting blood levels of glucose and lipids were recorded.

  2. Prevalence of polyhydramnios at a Danish hospital--a population-based study

    DEFF Research Database (Denmark)

    Bundgaard, Anne; Andersen, Betina Ristorp; Rode, Line

    2007-01-01

    BACKGROUND: The purpose of this study was to determine the incidence of polyhydramnios, the related maternal and perinatal morbidity, and to estimate the association between perinatal outcome and the degree of polyhydramnios in a Danish population. METHODS: The study population consisted of 168 w...

  3. Population-based surveillance for invasive pneumococcal disease in homeless adults in Toronto.

    Directory of Open Access Journals (Sweden)

    Agron Plevneshi

    Full Text Available BACKGROUND: Identification of high-risk populations for serious infection due to S. pneumoniae will permit appropriately targeted prevention programs. METHODS: We conducted prospective, population-based surveillance for invasive pneumococcal disease and laboratory confirmed pneumococcal pneumonia in homeless adults in Toronto, a Canadian city with a total population of 2.5 M, from January 1, 2002 to December 31, 2006. RESULTS: We identified 69 cases of invasive pneumococcal disease and 27 cases of laboratory confirmed pneumococcal pneumonia in an estimated population of 5050 homeless adults. The incidence of invasive pneumococcal disease in homeless adults was 273 infections per 100,000 persons per year, compared to 9 per 100,000 persons per year in the general adult population. Homeless persons with invasive pneumococcal disease were younger than other adults (median age 46 years vs 67 years, P<.001, and more likely than other adults to be smokers (95% vs. 31%, P<.001, to abuse alcohol (62% vs 15%, P<.001, and to use intravenous drugs (42% vs 4%, P<.001. Relative to age matched controls, they were more likely to have underlying lung disease (12/69, 17% vs 17/272, 6%, P = .006, but not more likely to be HIV infected (17/69, 25% vs 58/282, 21%, P = .73. The proportion of patients with recurrent disease was five fold higher for homeless than other adults (7/58, 12% vs. 24/943, 2.5%, P<.001. In homeless adults, 28 (32% of pneumococcal isolates were of serotypes included in the 7-valent conjugate vaccine, 42 (48% of serotypes included in the 13-valent conjugate vaccine, and 72 (83% of serotypes included in the 23-valent polysaccharide vaccine. Although no outbreaks of disease were identified in shelters, there was evidence of clustering of serotypes suggestive of transmission of pathogenic strains within the homeless population. CONCLUSIONS: Homeless persons are at high risk of serious pneumococcal infection. Vaccination, physical structure changes

  4. Limitations of correlation-based redatuming methods

    Science.gov (United States)

    Barrera P, D. F.; Schleicher, J.; van der Neut, J.

    2017-12-01

    Redatuming aims to correct seismic data for the consequences of an acquisition far from the target. That includes the effects of an irregular acquisition surface and of complex geological structures in the overburden such as strong lateral heterogeneities or layers with low or very high velocity. Interferometric techniques can be used to relocate sources to positions where only receivers are available and have been used to move acquisition geometries to the ocean bottom or transform data between surface-seismic and vertical seismic profiles. Even if no receivers are available at the new datum, the acquisition system can be relocated to any datum in the subsurface to which the propagation of waves can be modeled with sufficient accuracy. By correlating the modeled wavefield with seismic surface data, one can carry the seismic acquisition geometry from the surface closer to geologic horizons of interest. Specifically, we show the derivation and approximation of the one-sided seismic interferometry equation for surface-data redatuming, conveniently using Green’s theorem for the Helmholtz equation with density variation. Our numerical examples demonstrate that correlation-based single-boundary redatuming works perfectly in a homogeneous overburden. If the overburden is inhomogeneous, primary reflections from deeper interfaces are still repositioned with satisfactory accuracy. However, in this case artifacts are generated as a consequence of incorrectly redatumed overburden multiples. These artifacts get even worse if the complete wavefield is used instead of the direct wavefield. Therefore, we conclude that correlation-based interferometric redatuming of surface-seismic data should always be applied using direct waves only, which can be approximated with sufficient quality if a smooth velocity model for the overburden is available.

  5. Computerized tablet based versus traditional paper- based survey methods: results from adolescent's health research in schools of Maharashtra, India

    OpenAIRE

    Naveen Agarwal; Balram Paswan; Prakash H. Fulpagare; Dhirendra N Sinha; Thaksaphon Thamarangsi; Manju Rani

    2018-01-01

    Background and challenges to implementation Technological advancement is growing very fast in India and majority of young population is handling electronic devices often during leisure as well as at work. This study indicates that electronic tablets are less time consuming and improves survey response rate over the traditional paper-pencil survey method. Intervention or response An Android-based Global School-based Health Survey (GSHS) questionnaire was used with the...

  6. Addendum to "Population-Based Prevention of Child Maltreatment: The U.S. Triple P System Population Trial".

    Science.gov (United States)

    Prinz, Ronald J; Sanders, Matthew R; Shapiro, Cheri J; Whitaker, Daniel J; Lutzker, John R

    2016-04-01

    A previous article published several years ago (Prinz et al. Prevention Science, 10, 1-12, 2009) described the main results of a place-randomized-design study focused on the prevention of child-maltreatment-related outcomes at a population level through the implementation of a multilevel system of parenting and family support (the Triple P-Positive Parenting Program). The current report, prepared at the encouragement of the journal, provides additional details about procedures, measures, and design-related decisions, presents an additional analysis of the main outcome variables, and poses questions about the study and its implications. We also offer guidance about how the field can move forward to build on this line of research. From the outset, the three designated primary child maltreatment outcomes were county-wide rates for substantiated child maltreatment cases, out-of-home placements, and hospital-treated child maltreatment injuries, derived from independent data sources available through administrative archival records. Baseline equivalence between the two intervention conditions was reaffirmed. The additional analysis, which made use of a 5-year baseline (replacing a 1-year baseline) and ANCOVA, yielded large effect sizes for all three outcomes that converged with those from the original analyses. Overall, the study underscored the potential for community-wide parenting and family support to produce population-level preventive impact on child maltreatment. Issues addressed included (1) the need for replication of population-oriented maltreatment prevention strategies like the one tested in this randomized experiment, (2) the need to demonstrate that a parenting-based population approach to maltreatment prevention can also impact children's adjustment apart from child abuse, and (3) the role of implementation science for achieving greater population reach and maintenance over time.

  7. Oncogenic human papillomavirus genital infection in southern Iranian women: population-based study versus clinic-based data

    Directory of Open Access Journals (Sweden)

    Eghbali Seyed

    2012-09-01

    Full Text Available Abstract Background Epidemiological studies on genital human papilloma viruses infection (HPVs in general population are crucial for the implementation of health policy guidelines for developing the strategies to prevent the primary and secondary cervical cancer. In different parts of Iran, there is a lack of population-based studies to determine the prevalence of HPV in the general population. The aim of this population-based study is to compare the prevalence rate of genital HPV infection among reproductive women with our previous clinic-based data, which showed a prevalence rate of 5% in women in southern Iran. Results Using general primers for all genotypes of HPV, of 799 randomly selected women, five (0.63%, 95% CI 0.23-1.55% tested positive for HPV DNA. Overall, seven different HPV genotypes were detected: six types (16, 18, 31, 33, 51 and 56 were carcinogenic, or “high risk genotypes” and one genotype (HPV-66 was “probably carcinogenic.” Conclusions In a population-based study, the prevalence of HPV infection among southern Iranian women was lower than that observed worldwide. However, our gynaecological clinic-based study on the prevalence of HPV infection showed results comparable with other studies in the Middle East and Persian Gulf countries. Since gynaecological clinic-based data may generally overestimate HPV prevalence, estimates of prevalence according to clinic-based data should be adjusted downward by the population-based survey estimates.

  8. Area-level poverty and preterm birth risk: A population-based multilevel analysis

    Science.gov (United States)

    DeFranco, Emily A; Lian, Min; Muglia, Louis A; Schootman, Mario

    2008-01-01

    Background Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate. Methods Population-based study utilizing Missouri's birth certificate database (1989–1997). We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990). Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty) was the reference group. Results PTB rate of PTB poverty and increased through the 4th quartile (4.9%), p poverty was significantly associated with PTB risk. PTB risk (poverty, adjusted odds ratio (adjOR) 1.18 (95% CI 1.03, 1.35), with a similar effect at earlier gestational ages (birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies. PMID:18793437

  9. The population-based Barcelona-Asymptomatic Intracranial Atherosclerosis Study (ASIA: rationale and design

    Directory of Open Access Journals (Sweden)

    Pera Guillem

    2011-02-01

    Full Text Available Abstract Background Large-artery intracranial atherosclerosis may be the most frequent cause of ischemic stroke worldwide. Traditional approaches have attempted to target the disease when it is already symptomatic. However, early detection of intracranial atherosclerosis may allow therapeutic intervention while the disease is still asymptomatic. The prevalence and natural history of asymptomatic intracranial atherosclerosis in Caucasians remain unclear. The aims of the Barcelona-ASymptomatic Intracranial Atherosclerosis (ASIA study are (1 to determine the prevalence of ASIA in a moderate-high vascular risk population, (2 to study its prognostic impact on the risk of suffering future major ischemic events, and (3 to identify predictors of the development, progression and clinical expression of this condition. Methods/Design Cross-over and cohort, population-based study. A randomly selected representative sample of 1,503 subjects with a mild-moderate-high vascular risk (as defined by a REGICOR score ≥ 5% and with neither a history of cerebrovascular nor ischemic heart disease will be studied. At baseline, all individuals will undergo extracranial and transcranial Color-Coded Duplex (TCCD ultrasound examinations to detect presence and severity of extra and intracranial atherosclerosis. Intracranial stenoses will be assessed by magnetic resonance angiography (MRA. Clinical and demographic variables will be recorded and blood samples will be drawn to investigate clinical, biological and genetic factors associated with the presence of ASIA. A long-term clinical and sonographic follow-up will be conducted thereafter to identify predictors of disease progression and of incident vascular events. Discussion The Barcelona-ASIA is a population-based study aiming to evaluate the prevalence and clinical importance of asymptomatic intracranial large-artery atherosclerosis in Caucasians. The ASIA project may provide a unique scientific resource to better

  10. The Epidemiology of Functional Gastrointestinal Disorders in Mexico: A Population-Based Study

    Directory of Open Access Journals (Sweden)

    Aurelio López-Colombo

    2012-01-01

    Full Text Available Aims. The frequency of functional gastrointestinal disorders (FGIDs in the general population of Mexico is unknown. Methods. To determine the prevalence of FGIDs, associated depression, and health care utilization, a population-based sampling strategy was used to select 500 households in the State of Tlaxcala, in central Mexico. Household interviews were conducted by two trained physicians using the Rome II Modular Questionnaire, a health-care and medication used questionnaire and the CES-D depression scale. Results. The most common FGIDs were IBS: 16.0% (95% CI: 12.9–19.5; functional bloating: 10.8% (8.2–13.9; unspecified functional bowel disorder: 10.6% (8.0–13.6; and functional constipation (FC: 7.4% (5.3–10.1. Uninvestigated heartburn was common: 19.6% (16.2–23.4. All FGIDs were equally prevalent among both genders, except for IBS (P=0.001, IBS-C (P<0.001, IBS-A/M (P=0.049, and FC (P=0.039 which were more frequent in women. Subjects with FGIDs reported higher frequencies of medical visits: 34.6 versus 16.8%; use of medications: 40.7 versus 21.6%; (both P<0.001; and reported depression: 26.7 versus 6.7%, (P<0.001. Conclusion. In this first population-based study of FGIDs in Mexico, heartburn, IBS, functional distension, and FC were common. Only IBS, IBS-C, IBS-A/M, and FC were more frequent in women. Finally, FGIDs in Mexico had an increased burden of health care utilization and depression.

  11. Area-level poverty and preterm birth risk: A population-based multilevel analysis

    Directory of Open Access Journals (Sweden)

    Muglia Louis A

    2008-09-01

    Full Text Available Abstract Background Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate. Methods Population-based study utilizing Missouri's birth certificate database (1989–1997. We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990. Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty was the reference group. Results PTB th quartile (4.9%, p adjOR 1.18 (95% CI 1.03, 1.35, with a similar effect at earlier gestational ages (adjOR 1.27 (95% CI 1.06, 1.52. Conclusion Women residing in socioeconomically deprived areas are at increased risk of preterm birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies.

  12. Psychiatric morbidity in the community: A population based-study from Kerala

    Science.gov (United States)

    Shaji, K. S.; Raju, D.; Sathesh, V; Krishnakumar, P.; Punnoose, Varghese P.; Kiran, P. S; Mini, B. S.; Kumar, Shibu; Anish, P. K; Kaimal, Ganga G.; Gupthan, Lekshmy; Sumesh, T. P.; Nikhil, U. G; Cyriac, Nisha; Vinod, M. D.; Kumar, R. Prasad; Chandran, Ramesh; Rejani, P. P; Amrutha, R; Mahesh; Anand, TN

    2017-01-01

    Background: Estimates of psychiatric morbidity in the community will help service development. Participation of trained nonspecialist health-care providers will facilitate scaling up of services in resource-limited settings. Aims: This study aimed to estimate the prevalence of priority mental health problems in populations served by the District Mental Health Program (DMHP). Settings and Design: This is a population-based cross-sectional survey. Materials and Methods: We did stratified cluster sampling of households in five districts of Kerala. Trained Accredited Social Health Activists (ASHAs) identified people who had symptoms suggestive of schizophrenia or bipolar disorder. Clinicians evaluated the information collected by the ASHAs and designated individuals as probable cases of psychosis or noncases. Screening instruments such as General Health Questionnaire-12, CAGE questionnaire, and Everyday Abilities Scale for India were used for identifying common mental disorders (CMDs), clinically significant alcohol-related problems, and functional impairment. Results: We found 12.43% of the adult population affected by mental health conditions. We found CMD as most common with a prevalence of 9%. The prevalence of psychosis was 0.71%, clinically significant alcohol-related problems was 1.46%, and dementia and other cognitive impairments was 1.26%. We found informant-based case finding to be useful in the identification of psychosis. Conclusions: Mental health problems are common. Nonspecialist health-care providers can be trained to identify psychiatric morbidity in the community. Their participation will help in narrowing the treatment gap. Embedding operational research to DMHP will make scaling up more efficient. PMID:28827860

  13. Cancer survival in Cixian of China, 2003-2013: a population-based study.

    Science.gov (United States)

    Li, Dongfang; Li, Daojuan; Song, Guohui; Liang, Di; Chen, Chao; Zhang, Yachen; Gao, Zhaoyu; He, Yutong

    2018-04-01

    Cixian is one of the high-risk areas for upper gastrointestinal cancer in China and the world. From 2005, comprehensive population-based screening for upper gastrointestinal cancers has been conducted in Cixian. The aim of this study was to investigate population-based cancer survival from 2003 to 2013 and to explore the effect of screening on upper gastrointestinal cancer survival in Cixian. Observed survival was estimated using the life table method. The expected survival from the general population was calculated using all-cause mortality data from the population of Cixian with the EdererII method. Cixian cancer registry, with a total coverage of 6.88 million person years, recorded 19,628 cancer patients diagnosed during 2003-2013. In Cixian, from 2003 to 2013, there were 19,628 newly cancer cases and 13,984 cancer deaths, with an incidence rate of 285.37/100,000 and mortality rate of 203.31/100,000. The overall five-year relative cancer survival for patients diagnosed in Cixian in 2003-2013 was 22.53%. The relative survival for all cancers combined in Cixian had an overall upward trend from 2003 to 2013. Among upper gastrointestinal cancer in Cixian, the five-year relative survival for cardia gastric cancer was highest at 30.42%, followed by oesophageal cancer at 25.37% and noncardia gastric cancer at 18.93%. In 2013, the five-year relative survival for oesophageal cancer, cardia gastric cancer, and noncardia gastric cancer patients aged 45-69 years was 39.97% (95% CI: 34.52-45.43%), 51.74% (95% CI: 42.09-60.86%), and 37.43% (95% CI: 26.93-48.17%), respectively, the absolute values increasing 14.11%, 16.71%, and 14.92% compared with that in 2003. There is an increasing trend in overall survival for upper gastrointestinal cancer with early screening and treatment of cancer in Cixian. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  14. Methods of evaluating the consequences of irradiation of populations. Final report 1976-1980

    International Nuclear Information System (INIS)

    1983-01-01

    The present state of scientific knowledge does not make it possible to set a threshold for the effects of ionizing radiation on the health of individuals or of populations. The pessimistic assumption whereby any exposure is liable to have a harmful effect therefore remains the basis for the evaluation of standards. The resulting recommendations formulated by the ICRP (Publication No. 26) consist in a system of dose limits, which constitute the new foundation of radiation protection, the aim being to ensure that: - no source of exposure is unjustified, with due regard to the benefits occurring therefrom, - all necessary exposure is kept as low as reasonable achievable, economic and social factors being taken into account, - the dose equivalents received do not exceed certain specified limits. In order to attain this objective, it appeared necessary to have at our disposal, in the context of any project for an installation that is liable to cause exposure to ionizing radiation, means of evaluating the following: 1. the levels of exposure to the individuals and population groups concerned, 2. the resulting radiological detriment to man, 3. the economic and social impacts thereof. In view of the foregoing, therefore, methods for making such evaluation had to be developed. The aim of the Contract of Association concluded in 1976 between the European Atomic Energy Community and the French Commissariat a l'Energie Atomique is to develop methodology for evaluating the consequence of the irradiation of populations. It appeared necessary to have such methods for the purpose of implementing the latest recommendations of the International Commission for Radiological Protection (ICRP) and the Community Directives, in particular as regards the justification of exposure levels and the optimization of protection measures

  15.   Personal invitations for population-based breast cancer screening

    DEFF Research Database (Denmark)

    Saalasti-Koskinen, Ulla; Mäkelä, Marjukka; Saarenmaa, Irma

    2010-01-01

    participation free of charge and the benefits of detecting breast cancer early. Harm associated with screening was seldom mentioned; no unit mentioned the possibility of false-negative results or overtreatment. CONCLUSION: The screening units provided very variable information, which often was biased toward......RATIONALE AND OBJECTIVES: Women who are invited for breast cancer screening should get enough information about the benefits and harms of screening to make an informed decision on participation. Personal invitations are an important source of information, because all invited women receive them....... The objective of this study was to evaluate the information breast cancer screening units send to women invited for screening in Finland. MATERIALS AND METHODS: A questionnaire was sent to all breast cancer screening units in Finland in 2005 and 2008, and the information (eg, invitations, results letters...

  16. The establishment of tocopherol reference intervals for Hungarian adult population using a validated HPLC method.

    Science.gov (United States)

    Veres, Gábor; Szpisjak, László; Bajtai, Attila; Siska, Andrea; Klivényi, Péter; Ilisz, István; Földesi, Imre; Vécsei, László; Zádori, Dénes

    2017-09-01

    Evidence suggests that decreased α-tocopherol (the most biologically active substance in the vitamin E group) level can cause neurological symptoms, most likely ataxia. The aim of the current study was to first provide reference intervals for serum tocopherols in the adult Hungarian population with appropriate sample size, recruiting healthy control subjects and neurological patients suffering from conditions without symptoms of ataxia, myopathy or cognitive deficiency. A validated HPLC method applying a diode array detector and rac-tocol as internal standard was utilized for that purpose. Furthermore, serum cholesterol levels were determined as well for data normalization. The calculated 2.5-97.5% reference intervals for α-, β/γ- and δ-tocopherols were 24.62-54.67, 0.81-3.69 and 0.29-1.07 μm, respectively, whereas the tocopherol/cholesterol ratios were 5.11-11.27, 0.14-0.72 and 0.06-0.22 μmol/mmol, respectively. The establishment of these reference intervals may improve the diagnostic accuracy of tocopherol measurements in certain neurological conditions with decreased tocopherol levels. Moreover, the current study draws special attention to the possible pitfalls in the complex process of the determination of reference intervals as well, including the selection of study population, the application of internal standard and method validation and the calculation of tocopherol/cholesterol ratios. Copyright © 2017 John Wiley & Sons, Ltd.

  17. Triptycene-based dianhydrides, polyimides, methods of making each, and methods of use

    KAUST Repository

    Ghanem, Bader; Pinnau, Ingo; Swaidan, Raja

    2015-01-01

    A triptycene-based monomer, a method of making a triptycene-based monomer, a triptycene-based aromatic polyimide, a method of making a triptycene- based aromatic polyimide, methods of using triptycene-based aromatic polyimides, structures incorporating triptycene-based aromatic polyimides, and methods of gas separation are provided. Embodiments of the triptycene-based monomers and triptycene-based aromatic polyimides have high permeabilities and excellent selectivities. Embodiments of the triptycene-based aromatic polyimides have one or more of the following characteristics: intrinsic microporosity, good thermal stability, and enhanced solubility. In an exemplary embodiment, the triptycene-based aromatic polyimides are microporous and have a high BET surface area. In an exemplary embodiment, the triptycene-based aromatic polyimides can be used to form a gas separation membrane.

  18. Triptycene-based dianhydrides, polyimides, methods of making each, and methods of use

    KAUST Repository

    Ghanem, Bader

    2015-12-30

    A triptycene-based monomer, a method of making a triptycene-based monomer, a triptycene-based aromatic polyimide, a method of making a triptycene- based aromatic polyimide, methods of using triptycene-based aromatic polyimides, structures incorporating triptycene-based aromatic polyimides, and methods of gas separation are provided. Embodiments of the triptycene-based monomers and triptycene-based aromatic polyimides have high permeabilities and excellent selectivities. Embodiments of the triptycene-based aromatic polyimides have one or more of the following characteristics: intrinsic microporosity, good thermal stability, and enhanced solubility. In an exemplary embodiment, the triptycene-based aromatic polyimides are microporous and have a high BET surface area. In an exemplary embodiment, the triptycene-based aromatic polyimides can be used to form a gas separation membrane.

  19. An example of population-level risk assessments for small mammals using individual-based population models.

    Science.gov (United States)

    Schmitt, Walter; Auteri, Domenica; Bastiansen, Finn; Ebeling, Markus; Liu, Chun; Luttik, Robert; Mastitsky, Sergey; Nacci, Diane; Topping, Chris; Wang, Magnus

    2016-01-01

    This article presents a case study demonstrating the application of 3 individual-based, spatially explicit population models (IBMs, also known as agent-based models) in ecological risk assessments to predict long-term effects of a pesticide to populations of small mammals. The 3 IBMs each used a hypothetical fungicide (FungicideX) in different scenarios: spraying in cereals (common vole, Microtus arvalis), spraying in orchards (field vole, Microtus agrestis), and cereal seed treatment (wood mouse, Apodemus sylvaticus). Each scenario used existing model landscapes, which differed greatly in size and structural complexity. The toxicological profile of FungicideX was defined so that the deterministic long-term first tier risk assessment would result in high risk to small mammals, thus providing the opportunity to use the IBMs for risk assessment refinement (i.e., higher tier risk assessment). Despite differing internal model design and scenarios, results indicated in all 3 cases low population sensitivity unless FungicideX was applied at very high (×10) rates. Recovery from local population impacts was generally fast. Only when patch extinctions occured in simulations of intentionally high acute toxic effects, recovery periods, then determined by recolonization, were of any concern. Conclusions include recommendations for the most important input considerations, including the selection of exposure levels, duration of simulations, statistically robust number of replicates, and endpoints to report. However, further investigation and agreement are needed to develop recommendations for landscape attributes such as size, structure, and crop rotation to define appropriate regulatory risk assessment scenarios. Overall, the application of IBMs provides multiple advantages to higher tier ecological risk assessments for small mammals, including consistent and transparent direct links to specific protection goals, and the consideration of more realistic scenarios. © 2015 SETAC.

  20. Algebraic Verification Method for SEREs Properties via Groebner Bases Approaches

    Directory of Open Access Journals (Sweden)

    Ning Zhou

    2013-01-01

    Full Text Available This work presents an efficient solution using computer algebra system to perform linear temporal properties verification for synchronous digital systems. The method is essentially based on both Groebner bases approaches and symbolic simulation. A mechanism for constructing canonical polynomial set based symbolic representations for both circuit descriptions and assertions is studied. We then present a complete checking algorithm framework based on these algebraic representations by using Groebner bases. The computational experience result in this work shows that the algebraic approach is a quite competitive checking method and will be a useful supplement to the existent verification methods based on simulation.

  1. Planning Critical Infrastructure based on Population Growth and Environmental Constraints

    Directory of Open Access Journals (Sweden)

    Nabawiya Khamis Al Masuudi

    2018-02-01

    Full Text Available This study explores the impact of public school location/distribution and surrounding build environment based on its distance from the main street, service road, petrol stations in Sohar, Oman using GIS. Data have been collected from various official sources to fulfil the requirements of this study, which helped in constructing the geodatabase for this project. The results of this study demonstrated that there is an apparent inconsistency in public schools distribution, as most public schools are concentrated in one location. The study concludes with suggestions and recommendations to use GIS and spatial planning by the decision makers to make future sound decisions of building public schools. It is desirable to build schools in areas with lower percentages of highways and commercial sectors.

  2. Estimating Population Turnover Rates by Relative Quantification Methods Reveals Microbial Dynamics in Marine Sediment.

    Science.gov (United States)

    Kevorkian, Richard; Bird, Jordan T; Shumaker, Alexander; Lloyd, Karen G

    2018-01-01

    The difficulty involved in quantifying biogeochemically significant microbes in marine sediments limits our ability to assess interspecific interactions, population turnover times, and niches of uncultured taxa. We incubated surface sediments from Cape Lookout Bight, North Carolina, USA, anoxically at 21°C for 122 days. Sulfate decreased until day 68, after which methane increased, with hydrogen concentrations consistent with the predicted values of an electron donor exerting thermodynamic control. We measured turnover times using two relative quantification methods, quantitative PCR (qPCR) and the product of 16S gene read abundance and total cell abundance (FRAxC, which stands for "fraction of read abundance times cells"), to estimate the population turnover rates of uncultured clades. Most 16S rRNA reads were from deeply branching uncultured groups, and ∼98% of 16S rRNA genes did not abruptly shift in relative abundance when sulfate reduction gave way to methanogenesis. Uncultured Methanomicrobiales and Methanosarcinales increased at the onset of methanogenesis with population turnover times estimated from qPCR at 9.7 ± 3.9 and 12.6 ± 4.1 days, respectively. These were consistent with FRAxC turnover times of 9.4 ± 5.8 and 9.2 ± 3.5 days, respectively. Uncultured Syntrophaceae , which are possibly fermentative syntrophs of methanogens, and uncultured Kazan-3A-21 archaea also increased at the onset of methanogenesis, with FRAxC turnover times of 14.7 ± 6.9 and 10.6 ± 3.6 days. Kazan-3A-21 may therefore either perform methanogenesis or form a fermentative syntrophy with methanogens. Three genera of sulfate-reducing bacteria, Desulfovibrio , Desulfobacter , and Desulfobacterium , increased in the first 19 days before declining rapidly during sulfate reduction. We conclude that population turnover times on the order of days can be measured robustly in organic-rich marine sediment, and the transition from sulfate-reducing to methanogenic conditions stimulates

  3. Gender differences of cannabis smoking on serum leptin levels: population-based study

    Directory of Open Access Journals (Sweden)

    Fernanda P. Moreira

    2018-02-01

    Full Text Available Objective: To evaluate the serum leptin levels in cannabis smokers. Methods: This was a cross-sectional population-based study of participants between the ages of 18 and 35 years. The data were collected through a self-administered questionnaire covering sociodemographic data and the use of psychoactive substances. Leptin levels were measured using a commercial ELISA kit. Results: Of the 911 participants, 6.7% were identified as cannabis smokers and had significantly lower leptin levels (p = 0.008. When stratified by gender, there was a significant decrease in leptin levels among male smokers (p = 0.039. Conclusion: Cannabis smoking was linked to leptin levels in men, suggesting that the response to biological signals may be different between men and women.

  4. Nitrate in drinking water and colorectal cancer - a nationwide population-based follow-up study

    DEFF Research Database (Denmark)

    Schullehner, Jörg; Hansen, Birgitte; Pedersen, Carsten Bøcker

    Importance of work and objectives Studies have suggested that nitrate in drinking water increased the risk of colorectal cancer. However, often exposure estimations and study size were insufficient to yield unequivocal results. We addressed these challenges by conducting a detailed exposure...... assessment of the entire Danish population. Methodologies GIS methods were used to assign nitrate concentrations at the waterworks to the 2,779 water supply areas and 55,752 private wells. Annual nitrate concentrations were assigned to each resident of Denmark from 1978-2012, based on their exact address...... in the Civil Registration System. For each person the individual adult exposure (age 20-35) was calculated. Information on colon and rectal cancer diagnoses was obtained from the national Cancer Registry. Cox proportional hazard models using age as time scale were fit to assess the risk within exposure deciles...

  5. Effectiveness of a two-step population-based osteoporosis screening program using FRAX

    DEFF Research Database (Denmark)

    Rubin, K H; Rothmann, M J; Holmberg, T

    2018-01-01

    The Risk-stratified Osteoporosis Strategy Evaluation (ROSE) study investigated the effectiveness of a two-step screening program for osteoporosis in women. We found no overall reduction in fractures from systematic screening compared to the current case-finding strategy. The group of moderate......- to high-risk women, who accepted the invitation to DXA, seemed to benefit from the program. INTRODUCTION: The purpose of the ROSE study was to investigate the effectiveness of a two-step population-based osteoporosis screening program using the Fracture Risk Assessment Tool (FRAX) derived from a self......-administered questionnaire to select women for DXA scan. After the scanning, standard osteoporosis management according to Danish national guidelines was followed. METHODS: Participants were randomized to either screening or control group, and randomization was stratified according to age and area of residence. Inclusion...

  6. HLA associations and risk of posttransplant lymphoproliferative disorder in Danish population-based cohort

    DEFF Research Database (Denmark)

    Vase, Maja Ølholm; Maksten, Eva Futtrup; Strandhave, Charlotte

    2015-01-01

    Background: Posttransplant lymphoproliferative disorder (PTLD) is a feared complication to organ transplantation, associated with substantial morbidity and inferior survival. Risk factors for PTLD include T cell–depleting induction therapy and primary infection or reactivation of Epstein-Barr virus....... Possible associations between certain HLA types and the risk of developing PTLD have been reported by other investigators; however, results are conflicting. Methods: We conducted a retrospective, population-based study on 4295 Danish solid organ transplant patients from the Scandiatransplant database...... can be clinically useful after transplantation in personalized monitoring schemes. Given the strong linkage disequilibrium in the HLA region, the associations must be interpreted carefully. The large size, virtually complete ascertainment of cases and no loss to follow-up remain important strengths...

  7. A population-based prescription study of asthma drugs during pregnancy

    DEFF Research Database (Denmark)

    Olesen, Charlotte; Thrane, Nana; Nielsen, G.L.

    2001-01-01

    Background: Among the goals of gestational asthma, therapy is optimisation of pulmonary function. According to the US Food and Drug Administration, no asthma drugs can be considered ‘safe’ during pregnancy. Fear of adverse fetal effects may thus lead to restrictive use of asthma drugs during...... pregnancy, and no population-based studies concerning gestational asthma therapy exist. Objectives: To examine whether asthma drugs or changing intensity of asthma therapy during pregnancy was associated with deviations from expected values of gestational age, birth weight, length at birth, or malformations....... Methods: The Birth Registry was used to identify all 15,756 primiparous women who gave birth in the County of North Jutland between 1991 and 1996. According to the North Jutland Prescription Database, 303 of these women received prescriptions for asthma drugs during pregnancy. Women who did not purchase...

  8. Risk of schizophrenia in second-generation immigrants: a Danish population-based cohort study

    DEFF Research Database (Denmark)

    Cantor-Graae, Elizabeth; Pedersen, Carsten Bøcker

    2007-01-01

    Background. Urban birth, a risk factor for schizophrenia, is more frequent among second-generation immigrants. The aim of the current study was to determine whether the increased risk for schizophrenia found in second-generation immigrants is explained by the degree of urbanization of birthplace...... for urbanization of birthplace and parental characteristics reduced these risks slightly. However, urbanization had a lesser effect in second-generation immigrants than in Danes. History of residence abroad was a risk factor for schizophrenia, regardless of whether parents were foreign-born or native Danes...... and/or factors related to parentage, such as geographic origin or history of residence abroad during upbringing.Method. Using data from the Danish Civil Registration System (CRS), we established a population-based cohort of 2.0 million Danes (persons born in Denmark). Schizophrenia in cohort members...

  9. Safety from Crime and Physical Activity among Older Adults: A Population-Based Study in Brazil

    International Nuclear Information System (INIS)

    Corseuil, M.W.; Schneider, I.J.C.; Orsi, E.; Hallal, P.C.; Corseuil, H.X.

    2012-01-01

    Objective. To evaluate the association between safety from crime and physical activity among older adults. Methods. A population-based survey including 1,656 older adults (60+ years) took place in Florianopolis, Brazil, in 2009-2010. Commuting and leisure time physical activity were assessed through the long version of the International Physical Activity Questionnaire. Perception of safety from crime was assessed using the Neighbourhood Environment Walk ability Scale. Results. Perceiving the neighbourhood as safe during the day was related to a 25% increased likelihood of being active in leisure time (95% CI 1.02-1.53); general perception of safety was also associated with a 25% increase in the likelihood of being active in leisure time (95% CI 1.01-1.54). Street lighting was related to higher levels of commuting physical activity (prevalence ratio: 1.89; 95% CI 1.28-2.80). Conclusions. Safety investments are essential for promoting physical activity among older adults in Brazil

  10. The epidemiology of neck pain: what we have learned from our population-based studies

    Science.gov (United States)

    Côté, Pierre; Cassidy, J. David; Carroll, Linda

    2003-01-01

    Background: There are few population-based studies on the epidemiology of neck pain in the general population. Purpose: To synthesize the findings of two large population-based studies of the epidemiology of neck pain and whiplash-associated disorders from the province of Saskatchewan, Canada. Study Design and Methods: We conducted two population-based cohort studies of neck pain and its related disability in Saskatchewan, Canada. First, the Saskatchewan Health and Back Pain Survey was designed to determine the prevalence and factors associated with neck pain in randomly selected adults. Second, we conducted a cohort study of the incidence and prognosis of whiplash and studied whether a change in the insurance system from tort to no-fault was related to a reduction in the number of whiplash claims and faster recovery. Results: In 1995, the six-month prevalence of neck pain was 54.2% and 4.6% of adults experienced disabling neck pain in the previous six-months. Neck pain was associated with education, comorbidities, smoking, self-reported general health and a history of neck injury in a motor vehicle collision. The incidence of treated and/or compensated whiplash injury was estimated at 834/100,000 adults in 1994, and dropped by 28% to 598/100,000 adults in 1995, after tort reform. Compared to tort, the median time-to-recovery was more than 230 days faster under no-fault. The strongest predictors of recovery were age, gender, education, injury severity, lawyer involvement and type of initial care provider. Conclusion: Neck pain is a public health problem. The incidence and prognosis of whiplash injuries are greatly influenced by compensation for pain and suffering, legal factors, injury severity and sociodemographic characteristics. Overall, neck pain is a multifaceted disabling problem that deserves more attention. When treating patients with neck pain, clinicians need to recognize that it is more than a physical problem and that its prognosis is influenced by

  11. Comparison of gas dehydration methods based on energy ...

    African Journals Online (AJOL)

    Comparison of gas dehydration methods based on energy consumption. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... This study compares three conventional methods of natural gas (Associated Natural Gas) dehydration to carry out ...

  12. Building the Evidence Base for Population-Level Interventions: Barriers and Opportunities

    Science.gov (United States)

    Lifsey, Sarah; Cash, Amanda; Anthony, Jodi; Mathis, Sheryl; Silva, Sandra

    2015-01-01

    Population-level interventions focused on policy, systems, and environmental change strategies are increasingly being used to affect and improve the health of populations. At the same time, emphasis on implementing evidence-based public health practices and programming is increasing, particularly at the federal level. Valuing strategies in the…

  13. Mechanosensory based orienting behaviors in fluvial and lacustrine populations of mottled sculpin (Cottus bairdi)

    Science.gov (United States)

    Sheryl Coombs; Gary D. Grossman

    2006-01-01

    We compared prey-orienting and rheotactic behaviors in a fluvial (Coweeta Creek) and lacustrine (Lake Michigan) population of mottled sculpin. Blinded sculpin from both populations exhibited unconditioned, mechanosensory based rheotaxis to low velocity flows. Whereas Lake Michigan sculpin generally showed increasing levels of positive rheotaxis to increasing velocities...

  14. Sensor, a population-based cohort study on gastroenteritis in the Netherlands: incidence and etiology.

    NARCIS (Netherlands)

    Wit, M.A.S. de; Koopmans, M.P.G.; Kortbeek, L.M.; Wannet, W.J.B.; Vinje, J; Leusden, F. van; Bartelds, A.I.M.; Duynhoven, Y.T.H.P. van

    2001-01-01

    A prospective population-based cohort study with a nested case- control study was conducted to estimate the incidence of gastroenteritis and the associated pathogens in the general Dutch population. Follow-up of two consecutive cohorts was performed by weekly reporting cards from december 1998 to

  15. Relationship Status among Parents of Children with Autism Spectrum Disorders: A Population-Based Study

    Science.gov (United States)

    Freedman, Brian H.; Kalb, Luther G.; Zablotsky, Benjamin; Stuart, Elizabeth A.

    2012-01-01

    Despite speculation about an 80% divorce rate among parents of children with an Autism Spectrum Disorder (ASD), very little empirical and no epidemiological research has addressed the issue of separation and divorce among this population. Data for this study was taken from the 2007 National Survey of Children's Health, a population-based,…

  16. An individual-based model for population viability analysis of humpback chub in Grand Canyon

    Science.gov (United States)

    Pine, William Pine; Healy, Brian; Smith, Emily Omana; Trammell, Melissa; Speas, Dave; Valdez, Rich; Yard, Mike; Walters, Carl; Ahrens, Rob; Vanhaverbeke, Randy; Stone, Dennis; Wilson, Wade

    2013-01-01

    We developed an individual-based population viability analysis model (females only) for evaluating risk to populations from catastrophic events or conservation and research actions. This model tracks attributes (size, weight, viability, etc.) for individual fish through time and then compiles this information to assess the extinction risk of the population across large numbers of simulation trials. Using a case history for the Little Colorado River population of Humpback Chub Gila cypha in Grand Canyon, Arizona, we assessed extinction risk and resiliency to a catastrophic event for this population and then assessed a series of conservation actions related to removing specific numbers of Humpback Chub at different sizes for conservation purposes, such as translocating individuals to establish other spawning populations or hatchery refuge development. Our results suggested that the Little Colorado River population is generally resilient to a single catastrophic event and also to removals of larvae and juveniles for conservation purposes, including translocations to establish new populations. Our results also suggested that translocation success is dependent on similar survival rates in receiving and donor streams and low emigration rates from recipient streams. In addition, translocating either large numbers of larvae or small numbers of large juveniles has generally an equal likelihood of successful population establishment at similar extinction risk levels to the Little Colorado River donor population. Our model created a transparent platform to consider extinction risk to populations from catastrophe or conservation actions and should prove useful to managers assessing these risks for endangered species such as Humpback Chub.

  17. Prevalence, incidence and mortality of type 2 diabetes mellitus revisited : A prospective population-based study in The Netherlands (ZODIAC-1)

    NARCIS (Netherlands)

    Ubink-Veltmaat, LJ; Bilo, HJG; Groenier, KH; Houweling, ST; Rischen, RO; Meyboom-de Jong, B

    2003-01-01

    Background: To present actual data to estimate prevalence, incidence and mortality of known type 2 diabetes mellitus in all age categories in The Netherlands. Methods: Prospective population-based study between 1998 and 2000 in The Netherlands. Baseline population of 155,774 patients, registered

  18. Rare cancers in The Netherlands: a population-based study.

    Science.gov (United States)

    van der Zwan, Jan M; van Dijk, Boukje A C; Visser, Otto; van Krieken, Han J H J M; Capocaccia, Riccardo; Siesling, Sabine

    2018-07-01

    The conventional definition for rare disease is based on prevalence. Because of differences in prognosis, a definition on the basis of incidence was deemed to be more appropriate for rare cancers. Within the European RARECARE project, a definition was introduced that defines cancers as rare when the crude incidence rate is less than six per 100 000 per year. In this study, we applied the RARECARE definition for rare cancer to the Netherlands; this to identify the usefulness of the definition in a single country and to provide more insight into the burden of rare cancers in the Netherlands. Data for 2004 through 2008 were extracted from the Netherlands Cancer Registry and classified according to the RARECARE entities (tumour groupings). Crude and European standardized incidence rates were calculated. Out of the 260 entities, 223 (86%) were rare according to the definition, accounting for 14 000 cancers (17% of all). Considerable fluctuations in crude rates over years were observed for the major group of cancers. Rare tumours in the Netherlands constituted 17% of all newly diagnosed tumours, but were divided over 223 different entities, indicating the challenge that faces clinicians. To make the definition of rare cancers better applicable, it should be refined by taking into consideration the sex-specific incidence for sex-specific cancer sites. Moreover, a mean incidence over 5 years will provide more solid insight into the burden, eliminating large fluctuations in time of most of the cancers.

  19. Burden of Six Healthcare-Associated Infections on European Population Health: Estimating Incidence-Based Disability-Adjusted Life Years through a Population Prevalence-Based Modelling Study

    Science.gov (United States)

    Eckmanns, Tim; Abu Sin, Muna; Ducomble, Tanja; Harder, Thomas; Sixtensson, Madlen; Velasco, Edward; Weiß, Bettina; Kramarz, Piotr; Monnet, Dominique L.; Kretzschmar, Mirjam E.; Suetens, Carl

    2016-01-01

    Background Estimating the burden of healthcare-associated infections (HAIs) compared to other communicable diseases is an ongoing challenge given the need for good quality data on the incidence of these infections and the involved comorbidities. Based on the methodology of the Burden of Communicable Diseases in Europe (BCoDE) project and 2011–2012 data from the European Centre for Disease Prevention and Control (ECDC) point prevalence survey (PPS) of HAIs and antimicrobial use in European acute care hospitals, we estimated the burden of six common HAIs. Methods and Findings The included HAIs were healthcare-associated pneumonia (HAP), healthcare-associated urinary tract infection (HA UTI), surgical site infection (SSI), healthcare-associated Clostridium difficile infection (HA CDI), healthcare-associated neonatal sepsis, and healthcare-associated primary bloodstream infection (HA primary BSI). The burden of these HAIs was measured in disability-adjusted life years (DALYs). Evidence relating to the disease progression pathway of each type of HAI was collected through systematic literature reviews, in order to estimate the risks attributable to HAIs. For each of the six HAIs, gender and age group prevalence from the ECDC PPS was converted into incidence rates by applying the Rhame and Sudderth formula. We adjusted for reduced life expectancy within the hospital population using three severity groups based on McCabe score data from the ECDC PPS. We estimated that 2,609,911 new cases of HAI occur every year in the European Union and European Economic Area (EU/EEA). The cumulative burden of the six HAIs was estimated at 501 DALYs per 100,000 general population each year in EU/EEA. HAP and HA primary BSI were associated with the highest burden and represented more than 60% of the total burden, with 169 and 145 DALYs per 100,000 total population, respectively. HA UTI, SSI, HA CDI, and HA primary BSI ranked as the third to sixth syndromes in terms of burden of disease

  20. Dietary patterns associated with fall-related fracture in elderly Japanese: a population based prospective study

    Directory of Open Access Journals (Sweden)

    Yaegashi Nobuo

    2010-06-01

    Full Text Available Abstract Background Diet is considered an important factor for bone health, but is composed of a wide variety of foods containing complex combinations of nutrients. Therefore we investigated the relationship between dietary patterns and fall-related fractures in the elderly. Methods We designed a population-based prospective survey of 1178 elderly people in Japan in 2002. Dietary intake was assessed with a 75-item food frequency questionnaire (FFQ, from which dietary patterns were created by factor analysis from 27 food groups. The frequency of fall-related fracture was investigated based on insurance claim records from 2002 until 2006. The relationship between the incidence of fall-related fracture and modifiable factors, including dietary patterns, were examined. The Cox proportional hazards regression model was used to examine the relationships between dietary patterns and incidence of fall-related fracture with adjustment for age, gender, Body Mass Index (BMI and energy intake. Results Among 877 participants who agreed to a 4 year follow-up, 28 suffered from a fall-related fracture. Three dietary patterns were identified: mainly vegetable, mainly meat and mainly traditional Japanese. The moderately confirmed (see statistical methods groups with a Meat pattern showed a reduced risk of fall-related fracture (Hazard ratio = 0.36, 95% CI = 0.13 - 0.94 after adjustment for age, gender, BMI and energy intake. The Vegetable pattern showed a significant risk increase (Hazard ratio = 2.67, 95% CI = 1.03 - 6.90 after adjustment for age, gender and BMI. The Traditional Japanese pattern had no relationship to the risk of fall-related fracture. Conclusions The results of this study have the potential to reduce fall-related fracture risk in elderly Japanese. The results should be interpreted in light of the overall low meat intake of the Japanese population.

  1. The Global Trachoma Mapping Project: Methodology of a 34-Country Population-Based Study

    Science.gov (United States)

    Solomon, Anthony W.; Pavluck, Alexandre L.; Courtright, Paul; Aboe, Agatha; Adamu, Liknaw; Alemayehu, Wondu; Alemu, Menbere; Alexander, Neal D. E.; Kello, Amir Bedri; Bero, Berhanu; Brooker, Simon J.; Chu, Brian K.; Dejene, Michael; Emerson, Paul M.; Flueckiger, Rebecca M.; Gadisa, Solomon; Gass, Katherine; Gebre, Teshome; Habtamu, Zelalem; Harvey, Erik; Haslam, Dominic; King, Jonathan D.; Mesurier, Richard Le; Lewallen, Susan; Lietman, Thomas M.; MacArthur, Chad; Mariotti, Silvio P.; Massey, Anna; Mathieu, Els; Mekasha, Addis; Millar, Tom; Mpyet, Caleb; Muñoz, Beatriz E.; Ngondi, Jeremiah; Ogden, Stephanie; Pearce, Joseph; Sarah, Virginia; Sisay, Alemayehu; Smith, Jennifer L.; Taylor, Hugh R.; Thomson, Jo; West, Sheila K.; Willis, Rebecca; Bush, Simon; Haddad, Danny; Foster, Allen

    2015-01-01

    ABSTRACT Purpose: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. Methods: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to “health district” size: populations of 100,000–250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h × c is calculated to facilitate recruitment of 1019 children aged 1–9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1–9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. Results: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. Conclusion: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015. PMID:26158580

  2. A robust statistical method for association-based eQTL analysis.

    Directory of Open Access Journals (Sweden)

    Ning Jiang

    Full Text Available It has been well established that theoretical kernel for recently surging genome-wide association study (GWAS is statistical inference of linkage disequilibrium (LD between a tested genetic marker and a putative locus affecting a disease trait. However, LD analysis is vulnerable to several confounding factors of which population stratification is the most prominent. Whilst many methods have been proposed to correct for the influence either through predicting the structure parameters or correcting inflation in the test statistic due to the stratification, these may not be feasible or may impose further statistical problems in practical implementation.We propose here a novel statistical method to control spurious LD in GWAS from population structure by incorporating a control marker into testing for significance of genetic association of a polymorphic marker with phenotypic variation of a complex trait. The method avoids the need of structure prediction which may be infeasible or inadequate in practice and accounts properly for a varying effect of population stratification on different regions of the genome under study. Utility and statistical properties of the new method were tested through an intensive computer simulation study and an association-based genome-wide mapping of expression quantitative trait loci in genetically divergent human populations.The analyses show that the new method confers an improved statistical power for detecting genuine genetic association in subpopulations and an effective control of spurious associations stemmed from population structure when compared with other two popularly implemented methods in the literature of GWAS.

  3. Approaches to conserving natural enemy populations in greenhouse crops: current methods and future prospects

    NARCIS (Netherlands)

    Messelink, G.J.; Bennison, J.; Alomar, O.; Ingegno, B.L.; Tavella, L.; Shipp, L.; Palevsky, E.; Wäckers, F.L.

    2014-01-01

    Biological pest control in greenhouse crops is usually based on periodical releases of mass-produced natural enemies, and this method has been successfully applied for decades. However, in some cases there are shortcomings in pest control efficacy, which often can be attributed to the poor

  4. Analyses of Dynamics in Dairy Products and Identification of Lactic Acid Bacteria Population by Molecular Methods

    Directory of Open Access Journals (Sweden)

    Aytül Sofu

    2017-01-01

    Full Text Available Lactic acid bacteria (LAB with different ecological niches are widely seen in fermented meat, vegetables, dairy products and cereals as well as in fermented beverages. Lactic acid bacteria are the most important group of bacteria in dairy industry due to their probiotic characteristics and fermentation agents as starter culture. In the taxonomy of the lactic acid bacteria; by means of rep-PCR, which is the analysis of repetitive sequences that are based on 16S ribosomal RNA (rRNA gene sequence, it is possible to conduct structural microbial community analyses such as Restriction Fragment Length Polymorphism (RFLP analysis of DNA fragments of different sizes cut with enzymes, Random Amplified Polymorphic DNA (RAPD polymorphic DNA amplified randomly at low temperatures and Amplified Fragment-Length Polymorphism (AFLP-PCR of cut genomic DNA. Besides, in the recent years, non-culture-based molecular methods such as Pulse Field Gel Electrophoresis (PFGE, Denaturing Gradient Gel Electrophoresis (DGGE, Thermal Gradient Gel Electrophoresis (TGGE, and Fluorescence In-situ Hybridization (FISH have replaced classical methods once used for the identification of LAB. Identification of lactic acid bacteria culture independent regardless of the method will be one of the most important methods used in the future pyrosequencing as a Next Generation Sequencing (NGS techniques. This paper reviews molecular-method based studies conducted on the identification of LAB species in dairy products.

  5. Population based allele frequencies of disease associated polymorphisms in the Personalized Medicine Research Project.

    Science.gov (United States)

    Cross, Deanna S; Ivacic, Lynn C; Stefanski, Elisha L; McCarty, Catherine A

    2010-06-17

    There is a lack of knowledge regarding the frequency of disease associated polymorphisms in populations and population attributable risk for many populations remains unknown. Factors that could affect the association of the allele with disease, either positively or negatively, such as race, ethnicity, and gender, may not be possible to determine without population based allele frequencies.Here we used a panel of 51 polymorphisms previously associated with at least one disease and determined the allele frequencies within the entire Personalized Medicine Research Project population based cohort. We compared these allele frequencies to those in dbSNP and other data sources stratified by race. Differences in allele frequencies between self reported race, region of origin, and sex were determined. There were 19544 individuals who self reported a single racial category, 19027 or (97.4%) self reported white Caucasian, and 11205 (57.3%) individuals were female. Of the 11,208 (57%) individuals with an identifiable region of origin 8337 or (74.4%) were German.41 polymorphisms were significantly different between self reported race at the 0.05 level. Stratification of our Caucasian population by self reported region of origin revealed 19 polymorphisms that were significantly different (p = 0.05) between individuals of different origins. Further stratification of the population by gender revealed few significant differences in allele frequencies between the genders. This represents one of the largest population based allele frequency studies to date. Stratification by self reported race and region of origin revealed wide differences in allele frequencies not only by race but also by region of origin within a single racial group. We report allele frequencies for our Asian/Hmong and American Indian populations; these two minority groups are not typically selected for population allele frequency detection. Population wide allele frequencies are important for the design and

  6. Crossing Methods and Cultivation Conditions for Rapid Production of Segregating Populations in Three Grain Amaranth Species.

    Science.gov (United States)

    Stetter, Markus G; Zeitler, Leo; Steinhaus, Adrian; Kroener, Karoline; Biljecki, Michelle; Schmid, Karl J

    2016-01-01

    Grain amaranths (Amaranthus spp.) have been cultivated for thousands of years in Central and South America. Their grains are of high nutritional value, but the low yield needs to be increased by selection of superior genotypes from genetically diverse breeding populations. Amaranths are adapted to harsh conditions and can be cultivated on marginal lands although little is known about their physiology. The development of controlled growing conditions and efficient crossing methods is important for research on and improvement of this ancient crop. Grain amaranth was domesticated in the Americas and is highly self-fertilizing with a large inflorescence consisting of thousands of very small flowers. We evaluated three different crossing methods (open pollination, hot water emasculation and hand emasculation) for their efficiency in amaranth and validated them with genetic markers. We identified cultivation conditions that allow an easy control of flowering time by day length manipulation and achieved flowering times of 4 weeks and generation times of 2 months. All three different crossing methods successfully produced hybrid F1 offspring, but with different success rates. Open pollination had the lowest (10%) and hand emasculation the highest success rate (74%). Hot water emasculation showed an intermediate success rate (26%) with a maximum of 94% success. It is simple to perform and suitable for a more large-scale production of hybrids. We further evaluated 11 single nucleotide polymorphism (SNP) markers and found that they were sufficient to validate all crosses of the genotypes used in this study for intra- and interspecific hybridizations. Despite its very small flowers, crosses in amaranth can be carried out efficiently and evaluated with inexpensive SNP markers. Suitable growth conditions strongly reduce the generation time and allow the control of plant height, flowering time, and seed production. In combination, this enables the rapid production of segregating

  7. Numeric, Agent-based or System dynamics model? Which modeling approach is the best for vast population simulation?

    Science.gov (United States)

    Cimler, Richard; Tomaskova, Hana; Kuhnova, Jitka; Dolezal, Ondrej; Pscheidl, Pavel; Kuca, Kamil

    2018-02-01

    Alzheimer's disease is one of the most common mental illnesses. It is posited that more than 25 % of the population is affected by some mental disease during their lifetime. Treatment of each patient draws resources from the economy concerned. Therefore, it is important to quantify the potential economic impact. Agent-based, system dynamics and numerical approaches to dynamic modeling of the population of the European Union and its patients with Alzheimer's disease are presented in this article. Simulations, their characteristics, and the results from different modeling tools are compared. The results of these approaches are compared with EU population growth predictions from the statistical office of the EU by Eurostat. The methodology of a creation of the models is described and all three modeling approaches are compared. The suitability of each modeling approach for the population modeling is discussed. In this case study, all three approaches gave us the results corresponding with the EU population prediction. Moreover, we were able to predict the number of patients with AD and, based on the modeling method, we were also able to monitor different characteristics of the population. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Comparing population and incident data for optimal air ambulance base locations in Norway.

    Science.gov (United States)

    Røislien, Jo; van den Berg, Pieter L; Lindner, Thomas; Zakariassen, Erik; Uleberg, Oddvar; Aardal, Karen; van Essen, J Theresia

    2018-05-24

    Helicopter emergency medical services are important in many health care systems. Norway has a nationwide physician manned air ambulance service servicing a country with large geographical variations in population density and incident frequencies. The aim of the study was to compare optimal air ambulance base locations using both population and incident data. We used municipality population and incident data for Norway from 2015. The 428 municipalities had a median (5-95 percentile) of 4675 (940-36,264) inhabitants and 10 (2-38) incidents. Optimal helicopter base locations were estimated using the Maximal Covering Location Problem (MCLP) optimization model, exploring the number and location of bases needed to cover various fractions of the population for time thresholds 30 and 45 min, in green field scenarios and conditioned on the existing base structure. The existing bases covered 96.90% of the population and 91.86% of the incidents for time threshold 45 min. Correlation between municipality population and incident frequencies was -0.0027, and optimal base locations varied markedly between the two data types, particularly when lowering the target time. The optimal solution using population density data put focus on the greater Oslo area, where one third of Norwegians live, while using incident data put focus on low population high incident areas, such as northern Norway and winter sport resorts. Using population density data as a proxy for incident frequency is not recommended, as the two data types lead to different optimal base locations. Lowering the target time increases the sensitivity to choice of data.

  9. Occupational risk and chronic kidney disease: a population-based study in the United States adult population.

    Science.gov (United States)

    Rubinstein, Sofia; Wang, Chengwei; Qu, Wenchun

    2013-01-01

    Previous studies on occupational risk for chronic kidney disease (CKD) have analyzed a limited range of occupations and focused on nephrotoxins. The primary purpose of this study was to examine the relative risk for the occurrence of CKD between different occupations in the US adult population. This was a population-based survey study of 91,340 participants in the US, who completed the National Health Interview Survey, 2004 through 2008. The outcome variable, CKD, was defined as having weakening/failing kidneys in the past 12 months, as diagnosed by a physician. The predictor variable, occupation, was obtained using the census occupational codes, regrouped according to North American Industrial Classification System. After controlling for age, gender, hypertension, and education, and with the category Life, Physical, and Social Science Occupations as a reference group, the likelihood of developing CKD was 4.3 times higher in respondents working in Building, Grounds Cleaning and Maintenance Occupations, 4.4 times higher in Healthcare Practitioners and Technical Occupations, 4.7 times higher in Transportation and Material Moving Occupations and in Computer and Mathematical Occupations, 4.8 times higher in Production Occupations, 5.3 times higher in Food Preparation and Serving Related Occupations, and 6.1 times higher in Healthcare Support Occupations and in Legal Occupations. This study identified occupation groups in US adult population with increased risk for CKD. Alleviation of workplace stress is suggested as a goal for behavioral intervention in high-risk occupations.

  10. Comparison of Drive Counts and Mark-Resight As Methods of Population Size Estimation of Highly Dense Sika Deer (Cervus nippon Populations.

    Directory of Open Access Journals (Sweden)

    Kazutaka Takeshita

    Full Text Available Assessing temporal changes in abundance indices is an important issue in the management of large herbivore populations. The drive counts method has been frequently used as a deer abundance index in mountainous regions. However, despite an inherent risk for observation errors in drive counts, which increase with deer density, evaluations of the utility of drive counts at a high deer density remain scarce. We compared the drive counts and mark-resight (MR methods in the evaluation of a highly dense sika deer population (MR estimates ranged between 11 and 53 individuals/km2 on Nakanoshima Island, Hokkaido, Japan, between 1999 and 2006. This deer population experienced two large reductions in density; approximately 200 animals in total were taken from the population through a large-scale population removal and a separate winter mass mortality event. Although the drive counts tracked temporal changes in deer abundance on the island, they overestimated the counts for all years in comparison to the MR method. Increased overestimation in drive count estimates after the winter mass mortality event may be due to a double count derived from increased deer movement and recovery of body condition secondary to the mitigation of density-dependent food limitations. Drive counts are unreliable because they are affected by unfavorable factors such as bad weather, and they are cost-prohibitive to repeat, which precludes the calculation of confidence intervals. Therefore, the use of drive counts to infer the deer abundance needs to be reconsidered.

  11. Young people’s risk of suicide attempts in relation to parental death: A population-based register study

    DEFF Research Database (Denmark)

    Christiansen, Erik; Jakobsen, Ida Skytte

    2011-01-01

    Background:  The objective of this study was to examine the association between the death of a biological parent and subsequent suicide attempts by young people (aged 10–22 years), and to explore sociodemographic factors as modifying factors in the process. Methods:  The study used a nested case......–control design. The full study population was obtained from the Danish longitudinal registers and included all individuals born between 1983 and 1989 (n = 403,431 individuals). The 3,465 registered suicide attempters from that group were matched with 75,300 population-based control subjects. Potentially...

  12. An application of the variable-r method to subpopulation growth rates in a 19th century agricultural population

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    Corey Sparks

    2009-07-01

    Full Text Available This paper presents an analysis of the differential growth rates of the farming and non-farming segments of a rural Scottish community during the 19th and early 20th centuries using the variable-r method allowing for net migration. Using this method, I find that the farming population of Orkney, Scotland, showed less variability in their reproduction and growth rates than the non-farming population during a period of net population decline. I conclude by suggesting that the variable-r method can be used in general cases where the relative growth of subpopulations or subpopulation reproduction is of interest.

  13. Feasibility of wear compensation in micro EDM milling based on discharge counting and discharge population characterization

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; Tristo, G.

    2011-01-01

    This paper investigates the applicability of real time wear compensation in micro EDM milling based on discharge counting and discharge population characterization. Experiments were performed involving discharge counting and tool electrode wear measurement in a wide range of process parameters...

  14. Symptoms of anxiety and depression in childhood and use of MDMA: prospective, population based study

    NARCIS (Netherlands)

    Huizink, A.C.; Ferdinand, R.F.; Ende, J. van den; Verhulst, F.C.

    2006-01-01

    Objective To investigate whether using ecstasy (3,4-methylenedioxymethamphetamine, MDMA) is preceded by symptoms of behavioural and emotional problems in childhood and early adolescence. Design Prospective, longitudinal, population based study. Setting The Dutch province of

  15. Symptoms of anxiety and depression in childhood and use of MDMA: prospective, population based study

    NARCIS (Netherlands)

    A.C. Huizink (Anja); R.F. Ferdinand (Robert); J. van der Ende (Jan); F.C. Verhulst (Frank)

    2006-01-01

    textabstractOBJECTIVE: To investigate whether using ecstasy (3,4-methylenedioxymethamphetamine, MDMA) is preceded by symptoms of behavioural and emotional problems in childhood and early adolescence. DESIGN: Prospective, longitudinal, population based study SETTING: The Dutch

  16. An investigation of the statistical power of neutrality tests based on comparative and population genetic data

    DEFF Research Database (Denmark)

    Zhai, Weiwei; Nielsen, Rasmus; Slatkin, Montgomery

    2009-01-01

    In this report, we investigate the statistical power of several tests of selective neutrality based on patterns of genetic diversity within and between species. The goal is to compare tests based solely on population genetic data with tests using comparative data or a combination of comparative...... and population genetic data. We show that in the presence of repeated selective sweeps on relatively neutral background, tests based on the d(N)/d(S) ratios in comparative data almost always have more power to detect selection than tests based on population genetic data, even if the overall level of divergence...... selection. The Hudson-Kreitman-Aguadé test is the most powerful test for detecting positive selection among the population genetic tests investigated, whereas McDonald-Kreitman test typically has more power to detect negative selection. We discuss our findings in the light of the discordant results obtained...

  17. Spironolactone and risk of upper gastrointestinal events: population based case-control study

    NARCIS (Netherlands)

    K.M.C. Verhamme (Katia); G. Mosis (Georgio); B.H.Ch. Stricker (Bruno); M.C.J.M. Sturkenboom (Miriam); J.P. Dieleman (Jeanne)

    2006-01-01

    textabstractOBJECTIVE: To confirm and quantify any association between spironolactone and upper gastrointestinal bleeding and ulcers. DESIGN: Population based case-control study. SETTING: A primary care information database in the Netherlands. PARTICIPANTS: All people on the

  18. POPULATION BASED COLORECTAL CANCER SCREENING: COMPARISON OF TWO FAECAL OCCULT BLOOD TESTS

    Directory of Open Access Journals (Sweden)

    Miren Begoña eZubero

    2014-01-01

    Full Text Available Background: The aim of screening for colorectal cancer is to improve prognosis by the detection of cancer at its early stages. In order to inform the decision on the specific test to be used in the population-based programme in the Basque Autonomous Region (Spain, we compared two immunochemical faecal occult blood quantitative tests (I-FOBT. Methods: Residents of selected study areas, aged 50-69 years, were invited to participate in the screening. Two tests based on latex agglutination (OC-Sensor and FOB Gold were randomly assigned to different study areas. A colonoscopy was offered to patients with a positive test result. The cut-off point used to classify a result as positive, according to manufacturer’s recommendations, was 100 ng/ml for both tests. Results: The invited population included 37,999 individuals. Participation rates were 61.8% (n=11,162 for OC-Sensor and 59.1% (n=11,786 for FOB Gold, (p=0.008. Positive rate for OC-Sensor was 6.6% (n=737 and 8.5% (n=1,002 for FOB Gold, (pConclusions: OC-Sensor test appears to be superior for I-FOBT based CRC screening, given its acceptance, ease of use, associated small number of errors and its screening accuracy. FOB-Gold on the other hand, has higher rate of positive values, with more colonoscopies performed, it shows higher detection incidence rates, but involves more false positives.

  19. Osteoporosis-related fracture case definitions for population-based administrative data

    Directory of Open Access Journals (Sweden)

    Lix Lisa M

    2012-05-01

    Full Text Available Abstract Background Population-based administrative data have been used to study osteoporosis-related fracture risk factors and outcomes, but there has been limited research about the validity of these data for ascertaining fracture cases. The objectives of this study were to: (a compare fracture incidence estimates from administrative data with estimates from population-based clinically-validated data, and (b test for differences in incidence estimates from multiple administrative data case definitions. Methods Thirty-five case definitions for incident fractures of the hip, wrist, humerus, and clinical vertebrae were constructed using diagnosis codes in hospital data and diagnosis and service codes in physician billing data from Manitoba, Canada. Clinically-validated fractures were identified from the Canadian Multicentre Osteoporosis Study (CaMos. Generalized linear models were used to test for differences in incidence estimates. Results For hip fracture, sex-specific differences were observed in the magnitude of under- and over-ascertainment of administrative data case definitions when compared with CaMos data. The length of the fracture-free period to ascertain incident cases had a variable effect on over-ascertainment across fracture sites, as did the use of imaging, fixation, or repair service codes. Case definitions based on hospital data resulted in under-ascertainment of incident clinical vertebral fractures. There were no significant differences in trend estimates for wrist, humerus, and clinical vertebral case definitions. Conclusions The validity of administrative data for estimating fracture incidence depends on the site and features of the case definition.

  20. Patterns of cannabis use in patients with Inflammatory Bowel Disease: A population based analysis.

    Science.gov (United States)

    Weiss, Alexandra; Friedenberg, Frank

    2015-11-01

    Tobacco use patterns and effects in patients with Inflammatory Bowel Disease have been extensively studied, however the role and patterns of cannabis use remains poorly defined. Our aim was to evaluate patterns of marijuana use in a large population based survey. Cases were identified from the NHANES database from the National Center for Health Statistics for the time period from January, 2009 through December, 2010 as having ulcerative colitis or Crohn's disease, and exact matched with controls using the Propensity Score Module of SPSS, based on age, gender, and sample weighted using the nearest neighbor method. After weighting, 2084,895 subjects with IBD and 2013,901 control subjects were identified with no significant differences in demographic characteristics. Subjects with IBD had a higher incidence of ever having used marijuana/hashish (M/H) (67.3% vs. 60.0%) and an earlier age of onset of M/H use (15.7 years vs. 19.6 years). Patients with IBD were less likely to have used M/H every month for a year, but more likely to use a heavier amount per day (64.9% subjects with IBD used three or more joints per day vs. 80.5% of subjects without IBD used two or fewer joints per day). In multivariable logistic regression, presence of IBD, male gender, and age over 40 years predicted M/H use. Our study is the first to evaluate marijuana patterns in a large-scale population based survey. Older, male IBD patients have the highest odds of marijuana use. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Effects of population based screening for Chlamydia infections in the Netherlands limited by declining participation rates.

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    Boris V Schmid

    Full Text Available BACKGROUND: A large trial to investigate the effectiveness of population based screening for chlamydia infections was conducted in the Netherlands in 2008-2012. The trial was register based and consisted of four rounds of screening of women and men in the age groups 16-29 years in three regions in the Netherlands. Data were collected on participation rates and positivity rates per round. A modeling study was conducted to project screening effects for various screening strategies into the future. METHODS AND FINDINGS: We used a stochastic network simulation model incorporating partnership formation and dissolution, aging and a sexual life course perspective. Trends in baseline rates of chlamydia testing and treatment were used to describe the epidemiological situation before the start of the screening program. Data on participation rates was used to describe screening uptake in rural and urban areas. Simulations were used to project the effectiveness of screening on chlamydia prevalence for a time period of 10 years. In addition, we tested alternative screening strategies, such as including only women, targeting different age groups, and biennial screening. Screening reduced prevalence by about 1% in the first two screening rounds and leveled off after that. Extrapolating observed participation rates into the future indicated very low participation in the long run. Alternative strategies only marginally changed the effectiveness of screening. Higher participation rates as originally foreseen in the program would have succeeded in reducing chlamydia prevalence to very low levels in the long run. CONCLUSIONS: Decreasing participation rates over time profoundly impact the effectiveness of population based screening for chlamydia infections. Using data from several consecutive rounds of screening in a simulation model enabled us to assess the future effectiveness of screening on prevalence. If participation rates cannot be kept at a sufficient level

  2. The protocols for the 10/66 dementia research group population-based research programme

    OpenAIRE

    Salas Aquiles; Rodriguez Juan; McKeigue Paul; Jacob KS; Krishnamoorthy ES; Huang Yueqin; Guerra Mariella; Gavrilova Svetlana I; Dewey Michael; Arizaga Raul; Albanese Emiliano; Acosta Daisy; Ferri Cleusa P; Prince Martin; Sosa Ana

    2007-01-01

    Abstract Background Latin America, China and India are experiencing unprecedentedly rapid demographic ageing with an increasing number of people with dementia. The 10/66 Dementia Research Group's title refers to the 66% of people with dementia that live in developing countries and the less than one tenth of population-based research carried out in those settings. This paper describes the protocols for the 10/66 population-based and intervention studies that aim to redress this imbalance. Meth...

  3. Community-based population-level interventions for promoting child oral health.

    OpenAIRE

    de Silva, AM; Hegde, S; Akudo Nwagbara, B; Calache, H; Gussy, MG; Nasser, M; Morrice, HR; Riggs, E; Leong, PM; Meyenn, LK; Yousefi-Nooraie, R

    2016-01-01

    BACKGROUND: Dental caries and gingival and periodontal disease are commonly occurring, preventable chronic conditions. Even though much is known about how to treat oral disease, currently we do not know which community-based population-level interventions are most effective and equitable in preventing poor oral health. OBJECTIVES: Primary • To determine the effectiveness of community-based population-level oral health promotion interventions in preventing dental caries and gingival and period...

  4. Estimating leptospirosis incidence using hospital-based surveillance and a population-based health care utilization survey in Tanzania.

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    Holly M Biggs

    Full Text Available The incidence of leptospirosis, a neglected zoonotic disease, is uncertain in Tanzania and much of sub-Saharan Africa, resulting in scarce data on which to prioritize resources for public health interventions and disease control. In this study, we estimate the incidence of leptospirosis in two districts in the Kilimanjaro Region of Tanzania.We conducted a population-based household health care utilization survey in two districts in the Kilimanjaro Region of Tanzania and identified leptospirosis cases at two hospital-based fever sentinel surveillance sites in the Kilimanjaro Region. We used multipliers derived from the health care utilization survey and case numbers from hospital-based surveillance to calculate the incidence of leptospirosis. A total of 810 households were enrolled in the health care utilization survey and multipliers were derived based on responses to questions about health care seeking in the event of febrile illness. Of patients enrolled in fever surveillance over a 1 year period and residing in the 2 districts, 42 (7.14% of 588 met the case definition for confirmed or probable leptospirosis. After applying multipliers to account for hospital selection, test sensitivity, and study enrollment, we estimated the overall incidence of leptospirosis ranges from 75-102 cases per 100,000 persons annually.We calculated a high incidence of leptospirosis in two districts in the Kilimanjaro Region of Tanzania, where leptospirosis incidence was previously unknown. Multiplier methods, such as used in this study, may be a feasible method of improving availability of incidence estimates for neglected diseases, such as leptospirosis, in resource constrained settings.

  5. Estimating Leptospirosis Incidence Using Hospital-Based Surveillance and a Population-Based Health Care Utilization Survey in Tanzania

    Science.gov (United States)

    Biggs, Holly M.; Hertz, Julian T.; Munishi, O. Michael; Galloway, Renee L.; Marks, Florian; Saganda, Wilbrod; Maro, Venance P.; Crump, John A.

    2013-01-01

    Background The incidence of leptospirosis, a neglected zoonotic disease, is uncertain in Tanzania and much of sub-Saharan Africa, resulting in scarce data on which to prioritize resources for public health interventions and disease control. In this study, we estimate the incidence of leptospirosis in two districts in the Kilimanjaro Region of Tanzania. Methodology/Principal Findings We conducted a population-based household health care utilization survey in two districts in the Kilimanjaro Region of Tanzania and identified leptospirosis cases at two hospital-based fever sentinel surveillance sites in the Kilimanjaro Region. We used multipliers derived from the health care utilization survey and case numbers from hospital-based surveillance to calculate the incidence of leptospirosis. A total of 810 households were enrolled in the health care utilization survey and multipliers were derived based on responses to questions about health care seeking in the event of febrile illness. Of patients enrolled in fever surveillance over a 1 year period and residing in the 2 districts, 42 (7.14%) of 588 met the case definition for confirmed or probable leptospirosis. After applying multipliers to account for hospital selection, test sensitivity, and study enrollment, we estimated the overall incidence of leptospirosis ranges from 75–102 cases per 100,000 persons annually. Conclusions/Significance We calculated a high incidence of leptospirosis in two districts in the Kilimanjaro Region of Tanzania, where leptospirosis incidence was previously unknown. Multiplier methods, such as used in this study, may be a feasible method of improving availability of incidence estimates for neglected diseases, such as leptospirosis, in resource constrained settings. PMID:24340122

  6. Oral cancer in Cali, Colombia: a population-based analysis of incidence and mortality trends.

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    Dora Ordóñez

    2014-09-01

    Full Text Available Objective. To describe the time trends of the incidence and mortality rates of oral cancer (OC in Cali, Colombia between 1962-2007. Materials and methods. Age-standardized (Segi’s world population incidence (ASIR and mortality (ASMR rates for oral cancer were estimated using data from the Population-based Cancer Registry of Cali, Colombia and from the database of the Municipal Secretary of Public Health (MSPH respectively. Annual percentage change (APC was used to measure the changes in rates over time. Results. 1 637 new cases of oral cancer were registered in the CPCR and the mean age upon diagnosis was 60 years. The ASIR decreased from 1962-2007 in men APC= 1.3 (IC95%:-2.0; -0.6 and women APC= -1.0 (IC95%: -1.7; -0.4.The ASMR decreased from 1984-2001 only in men, APC=2.8 (IC95%: -4.1; -1.5. Conclusions. There was a significant decrease in the incidence and mortality rates for OC in Cali, Colombia. The type of tumor associated to these changes was the squamous cell carcinoma

  7. Prevalence and risk factors associated with dry eye symptoms: a population based study in Indonesia

    Science.gov (United States)

    Lee, A J; Lee, J; Saw, S-M; Gazzard, G; Koh, D; Widjaja, D; Tan, D T H

    2002-01-01

    Aim: To determine the prevalence and identify associated risk factors for dry eye syndrome in a population in Sumatra, Indonesia. Methods: A one stage cluster sampling procedure was conducted to randomly select 100 households in each of the five rural villages and one provincial town of the Riau province, Indonesia, from April to June 2001. Interviewers collected demographic, lifestyle, and medical data from 1058 participants aged 21 years or over. Symptoms of dry eye were assessed using a six item validated questionnaire. Presence of one or more of the six dry eye symptoms often or all the time was analysed. Presence of pterygium was documented. Results: Prevalence of one or more of the six dry eye symptoms often or all the time adjusted for age was 27.5% (95% confidence interval (CI) 24.8 to 30.2). After adjusting for all significant variables, independent risk factors for dry eye were pterygium (p<0.001, multivariate odds ratio (OR) 1.8; 95% CI 1.4 to 2.5) and a history of current cigarette smoking (p=0.05, multivariate OR 1.5; 95% CI 1.0 to 2.2). Conclusions: This population based study provides prevalence rates of dry eye symptoms in a tropical developing nation. From our findings, pterygium is a possible independent risk factor for dry eye symptoms. PMID:12446361

  8. Increasing prevalence and high incidence of celiac disease in elderly people: A population-based study

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    Vilppula Anitta

    2009-06-01

    Full Text Available Abstract Background Celiac disease may emerge at any age, but little is known of its appearance in elderly people. We evaluated the prevalence of the condition in individuals over 55 years of age, and determined the incidence of biopsy-proven celiac disease (CDb and celiac disease including seropositive subjects for anti-tissue transglutaminase antibodies (CDb+s. Methods The study based on prevalence figures in 2815 randomly selected subjects who had undergone a clinical examination and serologic screening for celiac disease in 2002. A second screening in the same population was carried out in 2005, comprising now 2216 individuals. Positive tissue transglutaminase antibodies were confirmed with small bowel biopsy. Results Within three years the prevalence of CDb increased from 2.13 to 2.34%, and that of CDb+s from 2.45 to 2.70%. Five new cases were found among patients previously seronegative; two had minor abdominal symptoms and three were asymptomatic. The incidence of celiac disease in 2002–2005 was 0.23%, giving an annual incidence of 0.08% in this population. Conclusion The prevalence of celiac disease was high in elderly people, but the symptoms were subtle. Repeated screening detected five biopsy-proven cases in three years, indicating that the disorder may develop even in the elderly. Increased alertness to the disorder is therefore warranted.

  9. Hyperhomocysteinemia is independently associated with albuminuria in the population-based CoLaus study

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    Paccaud Fred

    2011-09-01

    Full Text Available Abstract Background Increased serum levels of homocysteine and uric acid have each been associated with cardiovascular risk. We analyzed whether homocysteine and uric acid were associated with glomerular filtration rate (GFR and albuminuria independently of each other. We also investigated the association of MTHFR polymorphisms related to homocysteine with albuminuria to get further insight into causality. Methods This was a cross-sectional population-based study in Caucasians (n = 5913. Hyperhomocysteinemia was defined as total serum homocysteine ≥ 15 μmol/L. Albuminuria was defined as urinary albumin-to-creatinine ratio > 30 mg/g. Results Uric acid was associated positively with homocysteine (r = 0.246 in men and r = 0.287 in women, P P for trend P P = 0.004 were significantly associated with albuminuria, independently of hypertension and type 2 diabetes. The 2-fold higher risk of albuminuria associated with hyperhomocysteinemia was similar to the risk associated with hypertension or diabetes. MTHFR alleles related to higher homocysteine were associated with increased risk of albuminuria. Conclusions In the general adult population, elevated serum homocysteine and uric acid were associated with albuminuria independently of each other and of renal function.

  10. Associations among binge eating behavior patterns and gastrointestinal symptoms: a population-based study

    Science.gov (United States)

    Cremonini, F; Camilleri, M; Clark, MM; Beebe, TJ; Locke, GR; Zinsmeister, AR; Herrick, LM; Talley, NJ

    2009-01-01

    Background The psychological symptoms associated with binge eating disorder (BED) have been well documented. However, the physical symptoms associated with BED have not been explored. Gastrointestinal (GI) symptoms such as heartburn and diarrhea are more prevalent in obese adults, but the associations remain unexplained. Patients with bulimia have increased gastric capacity. The objective of the study was to examine if the severity of binge eating episodes would be associated with upper and lower GI symptoms. Methods Population-based survey of community residents through a mailed questionnaire measuring GI symptoms, frequency of binge eating episodes and physical activity level. The association of GI symptoms with frequency of binge eating episodes was assessed using logistic regression models adjusting for age, gender, body mass index (BMI) and physical activity level. Results In 4096 subjects, BED was present in 6.1%. After adjusting for BMI, age, gender, race, diabetes mellitus, socioeconomic status and physical activity level, BED was independently associated with the following upper GI symptoms: acid regurgitation (P symptoms: diarrhea (P symptoms in the general population, independent of the level of obesity. The relationship between increased GI symptoms and physiological responses to increased volume and calorie loads, nutritional selections and rapidity of food ingestion in individuals with BED deserves further study. PMID:19139750

  11. Randomized Trial of a Family-based, Automated, Conversational Obesity Treatment Program for Underserved Populations

    Science.gov (United States)

    Wright, J. A.; Phillips, B.D.; Watson, B.L.; Newby, P.K.; Norman, G. J.; Adams, W.G.

    2013-01-01

    Objective To evaluate the acceptability and feasibility of a scalable obesity treatment program integrated with pediatric primary care and delivered using interactive voice technology (IVR) to families from underserved populations. Design and Methods Fifty parent-child dyads (child 9–12 yrs, BMI >95th percentile) were recruited from a pediatric primary care clinic and randomized to either an IVR or a wait-list control (WLC) group. The majority were lower-income, African-American (72%) families. Dyads received IVR calls for 12 weeks. Call content was informed by two evidenced-based interventions. Anthropometric and behavioral variables were assessed at baseline and 3 mo follow-up. Results Forty-three dyads completed the study. IVR parents ate 1 cup more fruit than WLC (p 75% agreed that the calls were useful, made for people like them, credible, and helped them eat healthy foods. Conclusion An obesity treatment program delivered via IVR may be an acceptable and feasible resource for families from underserved populations. PMID:23512915

  12. The Association between Bone Quality and Atherosclerosis: Results from Two Large Population-Based Studies

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    V. Lange

    2017-01-01

    Full Text Available Objective. It is highly debated whether associations between osteoporosis and atherosclerosis are independent of cardiovascular risk factors. We aimed to explore the associations between quantitative ultrasound (QUS parameters at the heel with the carotid artery intima-media thickness (IMT, the presence of carotid artery plaques, and the ankle-brachial index (ABI. Methods. The study population comprised 5680 men and women aged 20–93 years from two population-based cohort studies: Study of Health in Pomerania (SHIP and SHIP-Trend. QUS measurements were performed at the heel. The extracranial carotid arteries were examined with B-mode ultrasonography. ABI was measured in a subgroup of 3853 participants. Analyses of variance and linear and logistic regression models were calculated and adjusted for major cardiovascular risk factors. Results. Men but not women had significantly increased odds for carotid artery plaques with decreasing QUS parameters independent of diabetes mellitus, dyslipidemia, and hypertension. Beyond this, the QUS parameters were not significantly associated with IMT or ABI in fully adjusted models. Conclusions. Our data argue against an independent role of bone metabolism in atherosclerotic changes in women. Yet, in men, associations with advanced atherosclerosis, exist. Thus, men presenting with clinical signs of osteoporosis may be at increased risk for atherosclerotic disease.

  13. Environmental factors in a population-based inception cohort of inflammatory bowel disease patients in Europe

    DEFF Research Database (Denmark)

    Burisch, J; Pedersen, Natalia; Cukovic-Cavka, S

    2014-01-01

    BACKGROUND AND AIMS: The incidence of inflammatory bowel disease (IBD) is increasing in Eastern Europe possibly due to changes in environmental factors towards a more "westernised" standard of living. The aim of this study was to investigate differences in exposure to environmental factors prior ...... and Western European patients differed in environmental factors prior to diagnosis. Eastern European patients exhibited higher occurrences of suspected risk factors for IBD included in the Western lifestyle.......BACKGROUND AND AIMS: The incidence of inflammatory bowel disease (IBD) is increasing in Eastern Europe possibly due to changes in environmental factors towards a more "westernised" standard of living. The aim of this study was to investigate differences in exposure to environmental factors prior...... to diagnosis in Eastern and Western European IBD patients. METHODS: The EpiCom cohort is a population-based, prospective inception cohort of 1560 unselected IBD patients from 31 European countries covering a background population of 10.1 million. At the time of diagnosis patients were asked to complete an 87...

  14. Background and Data Configuration Process of a Nationwide Population-Based Study Using the Korean National Health Insurance System

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    Sun Ok Song

    2014-10-01

    Full Text Available BackgroundThe National Health Insurance Service (NHIS recently signed an agreement to provide limited open access to the databases within the Korean Diabetes Association for the benefit of Korean subjects with diabetes. Here, we present the history, structure, contents, and way to use data procurement in the Korean National Health Insurance (NHI system for the benefit of Korean researchers.MethodsThe NHIS in Korea is a single-payer program and is mandatory for all residents in Korea. The three main healthcare programs of the NHI, Medical Aid, and long-term care insurance (LTCI provide 100% coverage for the Korean population. The NHIS in Korea has adopted a fee-for-service system to pay health providers. Researchers can obtain health information from the four databases of the insured that contain data on health insurance claims, health check-ups and LTCI.ResultsMetabolic disease as chronic disease is increasing with aging society. NHIS data is based on mandatory, serial population data, so, this might show the time course of disease and predict some disease progress, and also be used in primary and secondary prevention of disease after data mining.ConclusionThe NHIS database represents the entire Korean population and can be used as a population-based database. The integrated information technology of the NHIS database makes it a world-leading population-based epidemiology and disease research platform.

  15. Endoscopic Vasectomy of Male Feral Pigeons (Columba livia) as a Possible Method of Population Control.

    Science.gov (United States)

    Heiderich, Elisabeth; Schildger, Bernd; Lierz, Michael

    2015-03-01

    To evaluate whether single-entry endoscopic vasectomy of male feral pigeons (Columba livia) significantly reduced fertility and would potentially be valuable for control of feral pigeon populations, 252 male feral pigeons were caught in the city of Berne and endoscopically vasectomized. In this procedure, approximately 1 cm of the deferent duct was removed bilaterally. Rapid, uneventful recoveries occurred in 94% (237/252) of the pigeons, whereas 6% (15/252) died because of complications associated with the procedure, consisting of perforation of the ureter (9/15), major hemorrhage (5/15), and respiratory arrest (1/15). Mean anesthesia time was 23±6 minutes. The vasectomized males were habituated to 2 pigeon houses together with fertile females. Another pigeon house with fertile pairs acted as control. All eggs laid were candled weekly to assess fertility. In the 2 pigeon houses with vasectomized males, the mean fertilization rate was 0.9% (5/563), while in the control pigeon house, the rate was 100% (39/39). The results indicate that endoscopic vasectomy of male feral pigeons may be a promising tool for field control of feral pigeon populations, especially in combination with other methods such as pigeon houses.

  16. Use of antimicrobial drugs in general hospitals. I. Description of population and definition of methods.

    Science.gov (United States)

    Townsend, T R; Shapiro, M; Rosner, B; Kass, E H

    1979-06-01

    The patterns of use of antimicrobial drugs in a random sample of general hosptials in Pennsylvania were studied. The sample was tested for validity, and all deaths and discharges were analyzed for 10 random days drawn across the year spanning July 1973 to June 1974. Methods were developed for abstracting the hospital records and for determining the reproducibility of the findings of the physician and nonphysician chart reviewers. More than 99% of the requested charts were available. In the 5,288 charts reviewed, most of the required data were readily available. The study population was 84% white and 58% female; most patients were in hospitals that had more than 300 beds and that were located in towns with populations of greater than 10,000. In 41% of the 2,070 antimicrobial courses administered to almost 30% of the patients, an explicit clinical statement of why the drug was being given could be found in the chart. The information for review was found in clinical charts, but in half of the charts, the information required was not on face sheets and discharge summaries.

  17. A salutogenic approach to prevention of metabolic syndrome: a mixed methods population study.

    Science.gov (United States)

    Miettola, Juhani; Viljanen, Anna Maria

    2014-12-01

    To find a salutogenic approach for prevention of metabolic syndrome in primary care practice. An explanatory sequential mixed-methods procedure was used to find salutogenic approaches for lifestyle change by assessing individual need, potential, and personal motivation. Data from a population health survey and interviews that focused on a sense of coherence were analysed. Altogether 480 Finnish subjects participated in a population health survey, and 43 of them were interviewed. The 43 interviewees' data were included in the final analysis. With the health survey participants' liability for MetS was assessed, and the objective need for lifestyle intervention was determined. Through the focused interviews potential and personal motivation for lifestyle modification were explored. Finally the data of the 43 interviewed subjects were merged. Four possible lifestyle intervention approaches were identified for specific intervention. First, subjects with a strong sense of coherence only need encouragement to maintain a healthy lifestyle; second, professional support was found important for subjects with gaps in health awareness to improve health understanding; third, strengthening of social support for lifestyle change is necessary for subjects with various practical constraints in their everyday life; and fourth, strengthening of stress adaptation is important for subjects with redundant concerns about their health. Salutogenic client-centred lifestyle modification approaches should be part of primary care practice. Further, a cross-disciplinary approach is needed in primary care research and practice to combat the exploding lifestyle illnesses.

  18. Systems and methods for interpolation-based dynamic programming

    KAUST Repository

    Rockwood, Alyn

    2013-01-03

    Embodiments of systems and methods for interpolation-based dynamic programming. In one embodiment, the method includes receiving an object function and a set of constraints associated with the objective function. The method may also include identifying a solution on the objective function corresponding to intersections of the constraints. Additionally, the method may include generating an interpolated surface that is in constant contact with the solution. The method may also include generating a vector field in response to the interpolated surface.

  19. Systems and methods for interpolation-based dynamic programming

    KAUST Repository

    Rockwood, Alyn

    2013-01-01

    Embodiments of systems and methods for interpolation-based dynamic programming. In one embodiment, the method includes receiving an object function and a set of constraints associated with the objective function. The method may also include identifying a solution on the objective function corresponding to intersections of the constraints. Additionally, the method may include generating an interpolated surface that is in constant contact with the solution. The method may also include generating a vector field in response to the interpolated surface.

  20. Stroke trends in an aging population. The Technology Assessment Methods Project Team.

    Science.gov (United States)

    Niessen, L W; Barendregt, J J; Bonneux, L; Koudstaal, P J

    1993-07-01

    Trends in stroke incidence and survival determine changes in stroke morbidity and mortality. This study examines the extent of the incidence decline and survival improvement in the Netherlands from 1979 to 1989. In addition, it projects future changes in stroke morbidity during the period 1985 to 2005, when the country's population will be aging. A state-event transition model is used, which combines Dutch population projections and existing data on stroke epidemiology. Based on the clinical course of stroke, the model describes historical national age- and sex-specific hospital admission and mortality rates for stroke. It extrapolates observed trends and projects future changes in stroke morbidity rates. There is evidence of a continuing incidence decline. The most plausible rate of change is an annual decline of -1.9% (range, -1.7% to -2.1%) for men and -2.4% (range, -2.3% to -2.8%) for women. Projecting a constant mortality decline, the model shows a 35% decrease of the stroke incidence rate for a period of 20 years. Prevalence rates for major stroke will decline among the younger age groups but increase among the oldest because of increased survival in the latter. In absolute numbers this results in an 18% decrease of acute stroke episodes and an 11% increase of major stroke cases. The increase in survival cannot fully explain the observed mortality decline and, therefore, a concomitant incidence decline has to be assumed. Aging of the population partially outweighs the effect of an incidence decline on the total burden of stroke. Increase in cardiovascular survival leads to a further increase in major stroke prevalence among the oldest age groups.

  1. The INTERPHONE study: design, epidemiological methods, and description of the study population

    DEFF Research Database (Denmark)

    Cardis, Elisabeth; Richardson, Lesley; Deltour, Isabelle

    2007-01-01

    . This paper describes the study design and methods and the main characteristics of the study population. INTERPHONE is the largest case-control study to date investigating risks related to mobile phone use and to other potential risk factors for the tumours of interest and includes 2,765 glioma, 2......The very rapid worldwide increase in mobile phone use in the last decade has generated considerable interest in the possible health effects of exposure to radio frequency (RF) fields. A multinational case-control study, INTERPHONE, was set-up to investigate whether mobile phone use increases...... the risk of cancer and, more specifically, whether the RF fields emitted by mobile phones are carcinogenic. The study focused on tumours arising in the tissues most exposed to RF fields from mobile phones: glioma, meningioma, acoustic neurinoma and parotid gland tumours. In addition to a detailed history...

  2. Users’ dissatisfaction with dental care: a population-based household study

    Science.gov (United States)

    Martins, Andréa Maria Eleutério de Barros Lima; Ferreira, Raquel Conceição; dos Santos, Pedro Eleutério; Carreiro, Danilo Lima; Souza, João Gabriel Silva; Ferreira e Ferreira, Efigênia

    2015-01-01

    OBJECTIVE To examine whether demographic, socioeconomic conditions, oral health subjectivity and characterization of dental care are associated with users’ dissatisfaction with such are. METHODS Cross-sectional study of 781 people who required dental care in Montes Claros, MG, Southeastern Brazil, in 2012, a city with of medium-sized population situated in the North of Minas Gerais. Household interviews were conducted to assess the users’ dissatisfaction with dental care (dependent variable), demographic, socioeconomic conditions, oral health subjectivity and characterization of dental care (independent variables). Sample calculation was used for the finite population, with estimates made for proportions of dissatisfaction in 50.0% of the population, a 5.0% error margin, a non-response rate of 5.0% and a 2.0% design effect. Logistic regression was used, and the odds ratio was calculated with a 5% significance level and 95% confidence intervals. RESULTS Of the interviewed individuals, 9.0% (7.9%, with correction for design effect) were dissatisfied with the care provided. These were associated with lower educational level; negative self-assessment of oral health; perception that the care provider was unable to give dental care; negative evaluation of the way the patient was treated, the cleanliness of the rooms, based on the examination rooms and the toilets, and the size of the waiting and examination rooms. CONCLUSIONS The rate of dissatisfaction with dental care was low. This dissatisfaction was associated with socioeconomic conditions, subjectivity of oral health, skill of the health professionals relating to the professional-patient relationship and facility infrastructure. Educational interventions are suggested that aim at improving the quality of care among professionals by responsible agencies as is improving the infrastructure of the care units. PMID:26270017

  3. Does marriage protect against hospitalization with pneumonia? A population-based case-control study

    Directory of Open Access Journals (Sweden)

    Mor A

    2013-10-01

    Full Text Available Anil Mor, Sinna P Ulrichsen, Elisabeth Svensson, Klara Berencsi, Reimar W Thomsen Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark Background: To reduce the increasing burden of pneumonia hospitalizations, we need to understand their determinants. Being married may decrease the risk of severe infections, due to better social support and healthier lifestyle. Patients and methods: In this population-based case-control study, we identified all adult patients with a first-time pneumonia-related hospitalization between 1994 and 2008 in Northern Denmark. For each case, ten sex- and age-matched population controls were selected from Denmark's Civil Registration System. We performed conditional logistic regression analysis to estimate the odds ratios (ORs for pneumonia hospitalization among persons who were divorced, widowed, or never married, as compared with married persons, adjusting for age, sex, 19 different comorbidities, alcoholism-related conditions, immunosuppressant use, urbanization, and living with small children. Results: The study included 67,162 patients with a pneumonia-related hospitalization and 671,620 matched population controls. Compared with controls, the pneumonia patients were more likely to be divorced (10% versus 7% or never married (13% versus 11%. Divorced and never-married patients were much more likely to have previous diagnoses of alcoholism-related conditions (18% and 11%, respectively compared with married (3% and widowed (6% patients. The adjusted OR for pneumonia-related hospitalization was increased, at 1.29 (95% confidence interval [CI]: 1.25-1.33 among divorced; 1.15 (95% CI: 1.12-1.17 among widowed; and 1.33 (95% CI: 1.29-1.37 among never-married individuals as compared with those who were married. Conclusion: Married individuals have a decreased risk of being hospitalized with pneumonia compared with never-married, divorced, and widowed patients

  4. Users’ dissatisfaction with dental care: a population-based household study

    Directory of Open Access Journals (Sweden)

    Andréa Maria Eleutério de Barros Lima Martins

    2015-01-01

    Full Text Available OBJECTIVE To examine whether demographic, socioeconomic conditions, oral health subjectivity and characterization of dental care are associated with users’ dissatisfaction with such are.METHODS Cross-sectional study of 781 people who required dental care in Montes Claros, MG, Southeastern Brazil, in 2012, a city with of medium-sized population situated in the North of Minas Gerais. Household interviews were conducted to assess the users’ dissatisfaction with dental care (dependent variable, demographic, socioeconomic conditions, oral health subjectivity and characterization of dental care (independent variables. Sample calculation was used for the finite population, with estimates made for proportions of dissatisfaction in 50.0% of the population, a 5.0% error margin, a non-response rate of 5.0% and a 2.0% design effect. Logistic regression was used, and the odds ratio was calculated with a 5% significance level and 95% confidence intervals.RESULTS Of the interviewed individuals, 9.0% (7.9%, with correction for design effect were dissatisfied with the care provided. These were associated with lower educational level; negative self-assessment of oral health; perception that the care provider was unable to give dental care; negative evaluation of the way the patient was treated, the cleanliness of the rooms, based on the examination rooms and the toilets, and the size of the waiting and examination rooms.CONCLUSIONS The rate of dissatisfaction with dental care was low. This dissatisfaction was associated with socioeconomic conditions, subjectivity of oral health, skill of the health professionals relating to the professional-patient relationship and facility infrastructure. Educational interventions are suggested that aim at improving the quality of care among professionals by responsible agencies as is improving the infrastructure of the care units.

  5. Incidence and time trends of Herpes zoster in rheumatoid arthritis: a population-based cohort study

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    Veetil, Bharath Manu Akkara; Myasoedova, Elena; Matteson, Eric L.; Gabriel, Sherine E.; Green, Abigail B.; Crowson, Cynthia S.

    2012-01-01

    Objective To determine the incidence, time trends, risk factors and severity of herpes zoster (HZ) in a population-based incidence cohort of patients with rheumatoid arthritis (RA) compared to a group of individuals without RA from the same population. Methods All residents of Olmsted County, MN who first fulfilled 1987 American College of Rheumatology criteria for RA between 1/1/1980 and 12/31/2007 and a cohort of similar residents without RA were assembled and followed by retrospective chart review until death, migration, or 12/31/2008. Results There was no difference in the presence of HZ prior to RA incidence/index date between the cohorts (p=0.85). During follow-up 84 patients with RA (rate: 12.1 per 1000 person-years) and 44 subjects without RA (rate: 5.4 per 1000 person-years) developed HZ. Patients with RA were more likely to develop HZ than those without RA (hazard ratio: 2.4; 95% confidence interval: 1.7, 3.5). Patients diagnosed with RA in 1995–2007 had a higher likelihood of developing HZ than those diagnosed in 1980–1994. Erosive disease, previous joint surgery, use of hydroxychloroquine and corticosteroids were significantly associated with the development of HZ in RA, while the use of methotrexate or biologic agents was not. Complications of HZ occurred at a similar rate in both cohorts. Conclusion The incidence of HZ is increased in RA and has risen in recent years. The increasing incidence of HZ in more recent years is also noted in the general population. RA disease severity is associated with development of HZ. PMID:23281295

  6. Does childhood cancer affect parental divorce rates? A population-based study.

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    Syse, Astri; Loge, Jon H; Lyngstad, Torkild H

    2010-02-10

    PURPOSE Cancer in children may profoundly affect parents' personal relationships in terms of psychological stress and an increased care burden. This could hypothetically elevate divorce rates. Few studies on divorce occurrence exist, so the effect of childhood cancers on parental divorce rates was explored. PATIENTS AND METHODS Data on the entire Norwegian married population, age 17 to 69 years, with children age 0 to 20 years in 1974 to 2001 (N = 977,928 couples) were retrieved from the Cancer Registry, the Central Population Register, the Directorate of Taxes, and population censuses. Divorce rates for 4,590 couples who were parenting a child with cancer were compared with those of otherwise similar couples by discrete-time hazard regression models. Results Cancer in a child was not associated with an increased risk of parental divorce overall. An increased divorce rate was observed with Wilms tumor (odds ratio [OR], 1.52) but not with any of the other common childhood cancers. The child's age at diagnosis, time elapsed from diagnosis, and death from cancer did not influence divorce rates significantly. Increased divorce rates were observed for couples in whom the mothers had an education greater than high school level (OR, 1.16); the risk was particularly high shortly after diagnosis, for CNS cancers and Wilms tumors, for couples with children 0 to 9 years of age at diagnosis, and after a child's death. CONCLUSION This large, registry-based study shows that cancer in children is not associated with an increased parental divorce rate, except with Wilms tumors. Couples in whom the wife is highly educated appear to face increased divorce rates after a child's cancer, and this may warrant additional study.

  7. A community based study of NCD risk factors among adult population in Dehradun, India

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    Himanshu Agarwal

    2016-06-01

    Full Text Available Background: A Non-Communicable disease (NCD is one which is non-infectious and non-transmissible among people. NCDs account for leading causes of death and disease burden worldwide. To decrease the burden of NCDs experts stress on the importance of prevention and control with respect to modifiable risk factors. The World Health Organization's World Health Report 2002 identified tobacco use, alcohol consumption, overweight, physical inactivity, high blood pressure and high cholesterol as the most important risk factors for NCDs.(1  Aims & Objectives: 1. To know the prevalence of risk factors leading to NCDs in the study population. 2. To know the socio-demographic correlates associated with risk factors of NCDs. 3. To suggest appropriate recommendations regarding modifiable risk factors of NCDs in study population. Material & Methods: A Cross-sectional study, Community-based study among 18+ population in field practice areas of Community Medicine Department, SGRRIM&HS, Dehradun. Sample Size: 300 each in urban and rural, total 60. Results: The prevalence of Smoking was 11.3%, Smokeless tobacco use 10.5%, Alcohol use 13.2%, Unhealthy diet 99.5%, Low physical activity 0.8%, High BMI (≥ 25 kg/m2 51.2%, above normal waist-hip ratio 57.0%, Raised blood pressure 58.5% and raised blood sugar 25.2%. Conclusion: Smoking is significantly associated with age, sex and occupation. Raised blood pressure is significantly associated with age, sex and social class.

  8. Cardiovascular events in patients with atherothrombotic disease: a population-based longitudinal study in Taiwan.

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    Wen-Hsien Lee

    Full Text Available BACKGROUND: Atherothrombotic diseases including cerebrovascular disease (CVD, coronary artery disease (CAD, and peripheral arterial disease (PAD, contribute to the major causes of death in the world. Although several studies showed the association between polyvascular disease and poor cardiovascular (CV outcomes in Asian population, there was no large-scale study to validate this relationship in this population. METHODS AND RESULTS: This retrospective cohort study included patients with a diagnosis of CVD, CAD, or PAD from the database contained in the Taiwan National Health Insurance Bureau during 2001-2004. A total of 19954 patients were enrolled in this study. The atherothrombotic disease score was defined according to the number of atherothrombotic disease. The study endpoints included acute coronary syndrome (ACS, all strokes, vascular procedures, in hospital mortality, and so on. The event rate of ischemic stroke (18.2% was higher than that of acute myocardial infarction (5.7% in our patients (P = 0.0006. In the multivariate Cox regression analyses, the adjusted hazard ratios (HRs of each increment of atherothrombotic disease score in predicting ACS, all strokes, vascular procedures, and in hospital mortality were 1.41, 1.66, 1.30, and 1.14, respectively (P≦0.0169. CONCLUSIONS: This large population-based longitudinal study in patients with atherothrombotic disease demonstrated the risk of subsequent ischemic stroke was higher than that of subsequent AMI. In addition, the subsequent adverse CV events including ACS, all stroke, vascular procedures, and in hospital mortality were progressively increased as the increase of atherothrombotic disease score.

  9. The Urban Environment and Childhood Asthma (URECA birth cohort study: design, methods, and study population

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    Sandel Megan T

    2009-05-01

    Full Text Available Abstract Background The incidence and morbidity of wheezing illnesses and childhood asthma is especially high in poor urban areas. This paper describes the study design, methods, and population of the Urban Environment and Childhood Asthma (URECA study, which was established to investigate the immunologic causes of asthma among inner-city children. Methods and Results URECA is an observational prospective study that enrolled pregnant women in central urban areas of Baltimore, Boston, New York City, and St. Louis and is following their offspring from birth through age 7 years. The birth cohort consists of 560 inner-city children who have at least one parent with an allergic disease or asthma, and all families live in areas in which at least 20% of the population has incomes below the poverty line. In addition, 49 inner-city children with no parental history of allergies or asthma were enrolled. The primary hypothesis is that specific urban exposures in early life promote a unique pattern of immune development (impaired antiviral and increased Th2 responses that increases the risk of recurrent wheezing and allergic sensitization in early childhood, and of asthma by age 7 years. To track immune development, cytokine responses of blood mononuclear cells stimulated ex vivo are measured at birth and then annually. Environmental assessments include allergen and endotoxin levels in house dust, pre- and postnatal maternal stress, and indoor air nicotine and nitrogen dioxide. Nasal mucous samples are collected from the children during respiratory illnesses and analyzed for respiratory viruses. The complex interactions between environmental exposures and immune development will be assessed with respect to recurrent wheeze at age 3 years and asthma at age 7 years. Conclusion The overall goal of the URECA study is to develop a better understanding of how specific urban exposures affect immune development to promote wheezing illnesses and asthma.

  10. Evaluation of the Secretor Status of ABO Blood Group Antigens in Saliva among Southern Rajasthan Population Using Absorption Inhibition Method.

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    Metgud, Rashmi; Khajuria, Nidhi; Mamta; Ramesh, Gayathri

    2016-02-01

    The ABO blood group system was the significant element for forensic serological examination of blood and body fluids in the past before the wide adaptation of DNA typing. A significant proportion of individuals (80%) are secretors, meaning that antigens present in the blood are also found in other body fluids such as saliva. Absorption inhibition is one such method that works by reducing stre