Modelling and simulating decision processes of linked lives: An approach based on concurrent processes and stochastic race.

Individuals' decision processes play a central role in understanding modern migration phenomena and other demographic processes. Their integration into agent-based computational demography depends largely on suitable support by a modelling language. We are developing the Modelling Language for Linked Lives (ML3) to describe the diverse decision processes of linked lives succinctly in continuous time.

Multistate modelling extended by behavioural rules: An application to migration.

We propose to extend demographic multistate models by adding a behavioural element: behavioural rules explain intentions and thus transitions. Our framework is inspired by the Theory of Planned Behaviour. We exemplify our approach with a model of migration from Senegal to France.

Emigration Rates From Sample Surveys: An Application to Senegal.

What is the emigration rate of a country, and how reliable is that figure? Answering these questions is not at all straightforward. Most data on international migration are census data on foreign-born population. These migrant stock data describe the immigrant population in destination countries but offer limited information on the rate at which people leave their country of origin.

INTERNATIONAL MIGRATION. International migration under the microscope.

International migration affects all countries of the world. It is anticipated that in an increasingly interconnected world, migration will increase. People migrate for various reasons ranging from pursuing a better life to reuniting with families to escaping war and natural disaster.

Decision-Making in Agent-Based Models of Migration: State of the Art and Challenges.

We review agent-based models (ABM) of human migration with respect to their decision-making rules. The most prominent behavioural theories used as decision rules are the random utility theory, as implemented in the discrete choice model, and the theory of planned behaviour. We identify the critical choices that must be made in developing an ABM, namely the modelling of decision processes and social networks.

Compression or expansion of dementia in Germany? An observational study of short-term trends in incidence and death rates of dementia between 2006/07 and 2009/10 based on German health insurance data.

Introduction: There have been recent reports about a decline in dementia incidence, but only little is known about trends in the mortality of patients with dementia. Only the simultaneous analysis of both trends can inform whether the reported decline in dementia has led to a compression of dementia into higher ages.

Methods: We used health claims data from the largest public health insurer in Germany over the two time periods 2004/07 and 2007/10.

The proteome of erythrocyte-derived microparticles from plasma: new clues for erythrocyte aging and vesiculation.

Vesicle formation is an integral part of the physiological erythrocyte aging process. Recent biophysical and immunochemical data have suggested that vesicles originate by the extrusion of membrane patches that, during aging, have become damaged and simultaneously enriched in removal signals. Thereby, vesiculation may serve to postpone the untimely removal of functional cells.

Higher education delays and shortens cognitive impairment: a multistate life table analysis of the US Health and Retirement Study.

Improved health may extend or shorten the duration of cognitive impairment by postponing incidence or death. We assess the duration of cognitive impairment in the US Health and Retirement Study (1992-2004) by self reported BMI, smoking and levels of education in men and women and three ethnic groups. We define multistate life tables by the transition rates to cognitive impairment, recovery and death and estimate Cox proportional hazard ratios for the studied determinants.

Susceptibility to hyperosmotic stress-induced phosphatidylserine exposure increases during red blood cell storage.

Background: During storage of red blood cell (RBCs) before transfusion, RBCs undergo a series of structural and functional changes that include the exposure of phosphatidylserine (PS), a potent removal signal. It was postulated that, during blood bank storage, the susceptibility to stress-induced PS exposure increases, thereby rendering a considerable fraction of the RBCs susceptible to rapid removal after transfusion.

Study Design And Methods: RBCs were processed and stored following standard Dutch blood bank procedures.

Smoking kills, obesity disables: a multistate approach of the US Health and Retirement Survey.

Increasing BMI causes concerns about the consequences for health care. Decreasing cardiovascular mortality has lowered obesity-related mortality, extending duration of disability. We hypothesized increased duration of disability among overweight and obese individuals.

The burden of mortality of obesity at middle and old age is small. A life table analysis of the US Health and Retirement Survey.

The evidence of effect of overweight and obesity on mortality at middle and old age is conflicting. The increased relative risk of cardiovascular disease and diabetes for overweight and obese individuals compared to normal weight is well documented, but the absolute risk of cardiovascular death has decreased spectacularly since the 1980s. We estimate the burden of mortality of obesity among middle and old aged adults in the Health and Retirement Survey (HRS), a US prospective longitudinal study.

Erythrocyte vesiculation: a self-protective mechanism?

Previous studies demonstrated that 20% of haemoglobin is lost from circulating erythrocytes during their total lifespan by vesiculation. To study whether removal molecules other than membrane-bound haemoglobin were present in erythrocyte-derived vesicles, flow cytometry and immunoblot analysis were employed to examine the presence of phosphatidylserine (PS) and IgG, and senescent cell antigens respectively. It was demonstrated that 67% of glycophorin A-positive vesicles exposed PS, and that half of these vesicles also contained IgG.

Association between age at menarche and early-life nutritional status in rural Bangladesh.

Age at menarche is associated with anthropometry in adolescence. Recently, there has been growing support for the hypothesis that timing of menarche may be set early in life but modified by changes in body size and composition in childhood. To evaluate this, a cohort of 255 girls aged <5 years recruited in 1988 were followed up in 2001 in Matlab, Bangladesh.

Coeliac disease in Dutch patients with Hashimoto's thyroiditis and vice versa.

Aim: To define the association between Hashimoto's thyroiditis and coeliac disease in Dutch patients.

Methods: A total of 104 consecutive patients with Hashimoto's thyroiditis underwent coeliac serological tests (antigliadins, transglutaminase and endomysium antibodies) and HLA-DQ typing. Small intestinal biopsy was performed when any of coeliac serological tests was positive.

Disentangling women's responses on complex dietary intake patterns from an Indian cross-sectional survey: a latent class analysis.

Objective: To investigate the degree of individual heterogeneity related to complex dietary behaviour and to further examine the associations of different dietary compositions with selected characteristics.

Design: Latent class analysis was applied to data from the recent cross-sectional National Family Health Survey that collected information on the intake frequency of selected foods. Different responses regarding intake frequency were condensed into a set of five meaningful latent clusters representing different dietary patterns and these clusters were then labelled based on the reported degree of diet mixing.

Erythrocyte aging: a more than superficial resemblance to apoptosis?

In physiological circumstances, erythrocyte aging leads to binding of autologous IgG followed by recognition and removal through phagocytosis, mainly by Kupffer cells in the liver. This process is triggered by the appearance of a senescent erythrocyte-specific antigen. The functional and structural characteristics of senescent erythrocytes strongly suggest that this antigen originates on band 3, probably by calcium-induced proteolysis.

Liver Kupffer cells rapidly remove red blood cell-derived vesicles from the circulation by scavenger receptors.

Previous studies have shown that during the lifespan of red blood cells (RBCs) 20% of hemoglobin is lost by shedding of hemoglobin-containing vesicles. However, the fate of these vesicles is unknown. To study this fate we used a rat model, after having established that rat RBCs lose hemoglobin in the same way as human RBCs, and that RBC-derived vesicles are preferentially labeled by Na2(51) CrO4.

Compression of women's reproductive spans in Andhra Pradesh, India.

Context: The total fertility rate in Andhra Pradesh, India, has recently decreased to near-replacement level; however, the reasons for the fertility decline are unknown.

Methods: Data from the second round of the National Family Health Survey were used to examine the reproductive span-the duration between first marriage and menopause or sterilization-among 4,032 ever-married women aged 15-49 living in Andhra Pradesh in 1998-1999.

Results: Between 1992-1993 and 1998-1999, the median age at which women married remained at 15.

Smoking decreases the duration of life lived with and without cardiovascular disease: a life course analysis of the Framingham Heart Study.

Aims: To compare the burden of cardiovascular disease in terms of lifetime risk and life years lived with disease between smokers and non-smokers.

Methods And Results: We constructed multi-state life tables describing transitions through various cardiovascular diseases for 4723 smokers and non-smokers observed during 20 biannual observations in the Original Framingham Heart Study. Non-smokers live 8.

Intravenous midazolam sedation in pediatric diagnostic upper digestive endoscopy. A prospective study in a general hospital.

The positive role of benzodiazepines (Midazolam) in conscious sedation in pediatric patients is widely known. However, problems concerning the role of sedation in diagnostic upper endoscopy are a matter for debate as little is known about dosage and timing. We prospectively evaluated the efficacy, safety and optimal intravenous sedation dosage of midazolam in 257 consecutive patients, aged 2 months to 18 years old, who underwent upper endoscopy of the gastrointestinal tract.

Obesity in adulthood and its consequences for life expectancy: a life-table analysis.

Background: Overweight and obesity in adulthood are linked to an increased risk for death and disease. Their potential effect on life expectancy and premature death has not yet been described.

Objective: To analyze reductions in life expectancy and increases in premature death associated with overweight and obesity at 40 years of age.

Hemoglobin loss from erythrocytes in vivo results from spleen-facilitated vesiculation.

Previous studies have shown that approximately 20% of hemoglobin is lost from circulating red blood cells (RBCs), mainly during the second half of the cells' life span. Because hemoglobin-containing vesicles are known to circulate in plasma, these vesicles were isolated. Flow cytometry studies showed that most RBC-derived vesicles contain hemoglobin with all hemoglobin components present.

Weaning initiation patterns and subsequent linear growth progression among children aged 2-4 years in India.

Background: Reliance on full breastfeeding alone for a longer time could have deleterious nutritional and health implications at later stages of children's lives. About 47% of children are weaned at age >or=6 months and more than 50% of children in India under 4 years are stunted. We investigated the association between timing of weaning and stunting of children in India, using the data from National Family Health Survey, 1992-1993.