scholarly journals The Residential Population Generator (RPGen): Parameterization of Residential, Demographic, and Physiological Data to Model Intraindividual Exposure, Dose, and Risk

Toxics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 303
Author(s):  
Alexander East ◽  
Daniel Dawson ◽  
Graham Glen ◽  
Kristin Isaacs ◽  
Kathie Dionisio ◽  
...  
Keyword(s):  
Census Data ◽  
Chemical Exposure ◽  
Physiological Characteristics ◽  
Family Type ◽  
Interindividual Variation ◽  
Physiological Data ◽  
Single Individual ◽  
Intraindividual Variation ◽  
Exposure Models ◽  
Residential Population

Exposure to chemicals is influenced by associations between the individual’s location and activities as well as demographic and physiological characteristics. Currently, many exposure models simulate individuals by drawing distributions from population-level data or use exposure factors for single individuals. The Residential Population Generator (RPGen) binds US surveys of individuals and households and combines the population with physiological characteristics to create a synthetic population. In general, the model must be supported by internal consistency; i.e., values that could have come from a single individual. In addition, intraindividual variation must be representative of the variation present in the modeled population. This is performed by linking individuals and similar households across income, location, family type, and house type. Physiological data are generated by linking census data to National Health and Nutrition Examination Survey data with a model of interindividual variation of parameters used in toxicokinetic modeling. The final modeled population data parameters include characteristics of the individual’s community (region, state, urban or rural), residence (size of property, size of home, number of rooms), demographics (age, ethnicity, income, gender), and physiology (body weight, skin surface area, breathing rate, cardiac output, blood volume, and volumes for body compartments and organs). RPGen output is used to support user-developed chemical exposure models that estimate intraindividual exposure in a desired population. By creating profiles and characteristics that determine exposure, synthetic populations produced by RPGen increases the ability of modelers to identify subgroups potentially vulnerable to chemical exposures. To demonstrate application, RPGen is used to estimate exposure to Toluene in an exposure modeling case example.

scholarly journals Interindividual variation and consistency of migratory behavior in the Eurasian woodcock

2019 ◽  
Vol 66 (2) ◽  
pp. 155-163 ◽  
Author(s):  
Alessandro Tedeschi ◽  
Michele Sorrenti ◽  
Michele Bottazzo ◽  
Mario Spagnesi ◽  
Ibon Telletxea ◽  
...  
Keyword(s):  
Breeding Site ◽  
Interindividual Variation ◽  
Migratory Behavior ◽  
Temporal Consistency ◽  
Migration Routes ◽  
Intraindividual Variation ◽  
Scolopax Rusticola ◽  
Departure Date ◽  
Wintering Areas ◽  
Spatio Temporal

Abstract Diverse spatio-temporal aspects of avian migration rely on relatively rigid endogenous programs. However, flexibility in migratory behavior may allow effective coping with unpredictable variation in ecological conditions that can occur during migration. We aimed at characterizing inter- and intraindividual variation of migratory behavior in a forest-dwelling wader species, the Eurasian woodcock Scolopax rusticola, focusing on spatio-temporal consistency across repeated migration episodes. By satellite-tracking birds from their wintering sites along the Italian peninsula to their breeding areas, we disclosed a remarkable variability in migration distances, with some birds flying more than 6,000 km to Central Asian breeding grounds (up to 101°E). Prebreeding migration was faster and of shorter duration than postbreeding migration. Birds moving over longer distances migrated faster during prebreeding migration, and those breeding at northernmost latitudes left their wintering areas earlier. Moreover, birds making longer migrations departed earlier from their breeding sites. Breeding site fidelity was very high, whereas fidelity to wintering areas increased with age. Migration routes were significantly consistent, both among repeated migration episodes and between pre- and postbreeding migration. Prebreeding migration departure date was not significantly repeatable, whereas arrival date to the breeding areas was highly repeatable. Hence, interindividual variation in migratory behavior of woodcocks was mostly explained by the location of the breeding areas, and spatial consistency was relatively large through the entire annual cycle. Flexibility in prebreeding migration departure date may suggest that environmental effects have a larger influence on temporal than on spatial aspects of migratory behavior.

scholarly journals Physiological Characteristics and Nonparametric Test for Master-Slave Driving Task’s Mental Workload Evaluation in Mountain Area Highway at Night

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Haiwei Wang ◽  
Jianrong Liu ◽  
Feng You
Keyword(s):  
Driving Simulator ◽  
Mental Workload ◽  
Rapid Development ◽  
Nonparametric Test ◽  
Nonparametric Tests ◽  
Risk Identification ◽  
Physiological Characteristics ◽  
Physiological Data ◽  
Mountain Area ◽  
Driving Task

With the rapid development of advanced mobile intelligent terminals, driving tasks are diverse, and new traffic safety problems occur. We propose a new research on physiological characteristics and nonparametric tests for the master-slave driving task, especially for evaluation of drivers’ mental workload in mountain area highway in nighttime scenario. First, we establish the experimental platform based driving simulator and design the master-slave driving task. Second, based on the physiological data and subjective evaluation for mental workload, we use statistical methods to composite the physical changes evolution analysis in a driving simulator. Finally, we finished nonparametric test of the drivers’ psychological load and road test. The results show that in compassion with the daytime scenario, drivers should pay much effort to driving skills and risk identification in the nighttime scenario. Thus, in the same driving condition, drivers should bear the higher level of mental workload, and it has been subjected to even greater pressures and intensity of emotions.

The Number of Endovascular Trophoblasts in Maternal Blood Increases Overnight and after Physical Activity: An Experimental Study

2015 ◽  
Vol 40 (1) ◽  
pp. 54-58 ◽  
Author(s):  
Jacob Mørup Schlütter ◽  
Ida Kirkegaard ◽  
Anne Sigaard Ferreira ◽  
Lotte Hatt ◽  
Britta Christensen ◽  
...  
Keyword(s):  
Physical Activity ◽  
Experimental Study ◽  
Pregnant Women ◽  
Transvaginal Ultrasound ◽  
Maternal Blood ◽  
Interindividual Variation ◽  
Intraindividual Variation ◽  
Fetal Cells ◽  
Repeated Sampling ◽  
Endovascular Trophoblast

Introduction: Fetal cells in maternal blood may be used for noninvasive prenatal diagnostics, although their low number is a challenge. This study's objectives were to evaluate whether physical activity, transabdominal and transvaginal ultrasound scans of the uterus, as well as overnight or day-to-day variation affect the number of isolated fetal cells, more specifically the presumed endovascular trophoblast (pEVT). Material and Methods: In each of 3 different experiments, 10 normal singleton pregnant women (gestational age 10+4-14+4 weeks) participated. The number of pEVTs was assessed in 30-36 ml blood using specific markers for enrichment and identification. Results: The number of pEVTs increased overnight (p = 0.001) from a median of 1.5 to 3.5 and even further to a median of 6.0 after 30 min of physical activity (p = 0.04) but was not affected by transabdominal and transvaginal ultrasound scans. Repeated sampling showed that the interindividual variation of pEVTs was higher than the intraindividual variation (p < 0.001). However, even in pregnant women with a consistently low number of pEVTs, isolation of the pEVTs for prenatal diagnoses was possible in all cases by doing 2 separate blood samplings a few days apart. Discussion: The number of pEVTs identified in maternal blood can be increased by presampling conditions or repeated sampling.

scholarly journals Seasonal variation in sleeping metabolic rate, thyroid activity, and leptin

2003 ◽  
Vol 285 (2) ◽  
pp. E338-E343 ◽  
Author(s):  
Guy Plasqui ◽  
Arnold D. M. Kester ◽  
Klaas R. Westerterp
Keyword(s):  
Body Composition ◽  
Seasonal Variation ◽  
Metabolic Rate ◽  
Compartment Model ◽  
Fat Free Mass ◽  
Interindividual Variation ◽  
Dilution Method ◽  
Thyroid Activity ◽  
Intraindividual Variation ◽  
Total Thyroxine

We investigated seasonal variation in sleeping metabolic rate (SMR) and the possible relation to body composition, thyroid activity, and leptin. Twenty-five healthy volunteers were examined four times during the year: in spring (April, May), summer (July, August), autumn (October, November), and winter (January, February). Body composition was determined using a three-compartment model based on underwater weighing and the deuterium dilution method. SMR was measured during an overnight stay in a respiration chamber. A blood sample was taken for the analysis of free and total thyroxine, TSH, and leptin. SMR showed a significant seasonal variation ( P < 0.01) with a maximum in winter (4.54 kJ/min) and a minimum in summer (4.34 kJ/min). The amplitude was 0.10 ± 0.02 kJ/min, and the phase was November 5th. Season explained 17% of the intraindividual variation in SMR. The circannual rhythm in SMR could not be explained by changes in body composition, thyroid activity, or leptin. Interindividual variation in SMR was explained by fat-free mass ( P < 0.001) and leptin ( P < 0.001).

scholarly journals Intraindividual Stability of Human Erythrocyte Cholinesterase Activity

2007 ◽  
Vol 53 (7) ◽  
pp. 1358-1363 ◽  
Author(s):  
Lee J Lefkowitz ◽  
Joseph M Kupina ◽  
Nigel L Hirth ◽  
Rachel M Henry ◽  
Georgia Y Noland ◽  
...  
Keyword(s):  
Linear Regression Analysis ◽  
Policy Implications ◽  
Interindividual Variation ◽  
Medical Laboratory ◽  
Surveillance Program ◽  
Medical Surveillance ◽  
Intraindividual Variation ◽  
Us Army ◽  
The Mean ◽  
Medical Laboratory Technician

Abstract Background: Erythrocyte cholinesterase (RBC-ChE) activities serve as useful and sensitive biomarkers to monitor exposure to cholinesterase-inhibiting substances, such as chemical warfare nerve agents and pesticides. Although the interindividual variation of RBC-ChE is well characterized, the magnitude of intraindividual variation for RBC-ChE remains controversial. An accurate measure of intraindividual variation is critical for establishing the appropriate frequency of RBC-ChE testing. Methods: We retrospectively tracked the intraindividual variation of RBC-ChE activities among 46 male nerve agent workers from a single US Army depot that participated in a medical surveillance program requiring periodic RBC-ChE monitoring. All RBC-ChE analysis was performed by the same medical laboratory technician by the delta pH method. Results: A mean of 38 and a median of 37 RBC-ChE measurements were available for each worker. The mean duration of employment for these workers was 20 years (median, 21 years). The mean CV for RBC-ChE in this set of 46 workers was 3.9%. Linear regression analysis of the data for each worker resulted in a mean slope of 0.0010 delta pH units/h per year. Conclusions: RBC-ChE activities increased in each person by a mean of 0.01 delta pH units/h every 10 years, which is a negligible rate. These findings highlight the stability of RBC-ChE activities over time in a given individual and may have important policy implications regarding the appropriate frequency of RBC-ChE testing.

scholarly journals Regional based exposure models to account for local building typologies

2021 ◽  
Author(s):  
G. Tocchi ◽  
M. Polese ◽  
M. Di Ludovico ◽  
A. Prota
Keyword(s):  
Seismic Risk ◽  
Large Scale ◽  
Census Data ◽  
Construction Material ◽  
Regional Scale ◽  
Exposure Model ◽  
Masonry Building ◽  
Building Inventory ◽  
Exposure Models ◽  
Regional Vulnerability

AbstractThe development of building inventory is a fundamental step for the evaluation of the seismic risk at territorial scale. Census data are usually employed for building inventory in large scale application and their use requires suitable rules to assign buildings typologies to vulnerability classes, that is an exposure model specific for the considered vulnerability model. Several exposure models are developed proposing class assignment rules that are calibrated on building typological data available from post-earthquake survey data. However, this approach has the drawback of being based on data from specific geographic areas that have been hit by damaging earthquakes. Indeed, the distribution of building typologies can vary greatly for different areas of a country and the diffusion of one building’s typology rather than another one may depend on the availability of construction material in the area, the evolution of construction techniques and the codes in force at the time of construction. This paper aims to improve the exposure modelling at regional scale, investigating the variability of masonry building typologies distribution. It proposes a methodology to recalibrate the exposure models at regional scale and evaluates the influence of the improved characterization of regional vulnerability on damage and risk assessment. The study shows that the analysis of local building typologies may strongly impact on the evaluation of the seismic risk at territorial scale.

Variation of Phylioquinone (Vitamin K1) Concentrations in Hemodialysis Patients

1995 ◽  
Vol 74 (05) ◽  
pp. 1252-1254 ◽  
Author(s):  
Martin Kohlmeier ◽  
Jörg Saupe ◽  
Hans-Joachim Drossel ◽  
Martin J Shearer
Keyword(s):  
Important Determinant ◽  
Apoe Genotype ◽  
Serum Triglyceride ◽  
Hemodialysis Patients ◽  
Interindividual Variation ◽  
Residual Variance ◽  
Vitamin K1 ◽  
Serum Concentrations ◽  
Intraindividual Variation ◽  
Apolipoprotein E Genotypes

SummaryIntra- and interindividual variation of phylloquinone (vitamin K1) concentrations was investigated by repeat analysis of serum from 28 hemodialysis patients with different apolipoprotein E genotypes. Phylloquinone concentrations ranged from 0.1 to 9.0 nM, with a mean of 1.08 nM (standard deviation 1.90 nM).Most of the variation in serum phylloquinone concentrations was due to differences between patients; the ratio of intra-to interindividual variation was 0.17. Serum triglyceride concentrations and apoE genotype together accounted for 64% of interindividual variation; in contrast, only 6% of intraindividual variation could be attributed to differences in triglyceride concentrations.The small residual variance implies that different phylloquinone consumption levels contributed relatively little to the variation of serum concentrations (<36% of interindividual variance). The results suggest that individual disposition is a more important determinant of serum phylloquinone concentrations than dietary phylloquinone intake.

scholarly journals On the importance of intraindividual variation in nutritional research

2020 ◽  
Vol 11 (6) ◽  
pp. 511-517
Author(s):  
O.F.A. Larsen ◽  
E. Claassen ◽  
R.J. Brummer
Keyword(s):  
Statistical Power ◽  
Intervention Studies ◽  
Dietary Habits ◽  
Nutritional Intervention ◽  
Interindividual Variation ◽  
Intraindividual Variation ◽  
Potential Efficacy ◽  
Determining Factors ◽  
Study Population ◽  
Study Participants

Nutritional intervention studies, like those with pre- and probiotics, are often hampered by low effect sizes, reducing the power to demonstrate potential efficacy. Here, we perform computer simulations of a hypothetical clinical trial using such an intervention in order to elucidate determining factors that can be influenced in order to optimise the statistical power. Our simulations demonstrate that steering the study population towards a low intraindividual variation dramatically improves statistical power. A more than 10-fold decrease of number-to-treat could be reached. Also, a careful balancing between the number of subjects and measurements per subject, in combination with possible stratification of the subjects into responders and non-responders, based on inherent intraindividual variation, improves the likelihood to reach statistically significant results. Our results also show that traditional dogmas, with respect to clinical trials, i.e. aiming at low interindividual variation and a high number (n) of study participants, should be re-evaluated in favour of reducing intraindividual variation. This reduction in intraindividual variation could be achieved by maintaining a steady lifestyle, including dietary habits among others, within the timeframe of the intervention study.

scholarly journals Neighborhood Residence and Assessments of Racial Profiling Using Census Data

2019 ◽  
Vol 5 ◽  
pp. 237802311881874
Author(s):  
Lance Hannon
Keyword(s):  
At Risk ◽  
Racial Disparities ◽  
Census Data ◽  
Racial Profiling ◽  
Future Research ◽  
Racial Composition ◽  
Racial Disproportionality ◽  
Population At Risk ◽  
Residential Population

People frequently compare the racial composition of stopped individuals with the racial composition of the local residential population to assess unequal policing. This type of evaluation rests on the assumption that the census-derived population accurately reflects the population at risk to be stopped. For vehicle stops, existing research indicates that this assumption is very problematic, resulting in highly unreliable assessments of black-white policing disparities. However, there is little research on the significance of this assumption for stopped urban pedestrians. Analyzing more than 100,000 investigatory stops in Chicago, the present study finds that similar to vehicle stops, most pedestrian investigations do not involve neighborhood residents, and estimates of racial disproportionality are inflated when this issue is ignored. Still, the degree to which estimates are inflated appears less than that previously reported for vehicle stops, and sizable racial disparities remain unexplained after the issue is taken into account. Implications for future research are discussed.

scholarly journals Trends in Maori and Non-Maori Labour Force Participation, Incomes and Restructuring, 1981 to 1991

1970 ◽  
Author(s):  
Ben Amey
Keyword(s):  
Census Data ◽  
Labour Force ◽  
Economic Restructuring ◽  
Labour Force Participation ◽  
Family Type ◽  
Relative Impact ◽  
Participation Rates ◽  
Income Levels ◽  
Labour Force Status ◽  
Distribution Trends

The aim of this paper is to determine the relative impact of economic restructuring on Maori during the 1980s and early 1990s. The data come from special tabulations compiled from Census data. A combination of income classes and medians are used as measures to identify trends by ethnicity, family type, and labour force status. In particular, Maori and Non-Maori labour force participation rates are compared with income distribution trends to determine relationships between income levels and labour force participation. The degree of Maori income inequality increased during the 1980s both relative to 1981 and to Non-Maori families in 1991.

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