Migration and the epidemiological transition: insights from the Agincourt sub-district of northeast South Africa

KIMBACKGROUND: Migration and urbanization are central to sustainable development and health, but data on temporal trends in defined populations are scarce. Healthy men and women migrate because opportunities for employment and betterment are not equally distributed geographically. The disruption can result in unhealthy exposures and environments and income returns for the origin household. OBJECTIVES: The objectives of the paper are to describe the patterns, levels, and trends of temporary migration in rural northeast South Africa; the mortality trends by cause category over the period 2000-2011; and the associations between temporary migration and mortality by broad cause of death categories. METHOD: Longitudinal, Agincourt Health and Demographic Surveillance System data are used in a continuous, survival time, competing-risk model. FINDINGS: In rural, northeast South Africa, temporary migration, which involves migrants relocating mainly for work purposes and remaining linked to the rural household, is more important than age and sex in explaining variations in mortality, whatever the cause. In this setting, the changing relationship between temporary migration and communicable disease mortality is primarily affected by reduced exposure of the migrant to unhealthy conditions. The study suggests that the changing relationship between temporary migration and non-communicable disease mortality is mainly affected by increased livelihood benefits of longer duration migration. CONCLUSION: Since temporary migration is not associated with communicable diseases only, public health policies should account for population mobility whatever the targeted health risk. There is a need to strengthen the rural health care system, because migrants tend to return to the rural households when they need health care

Géochimie d'une toposéquence de sols tropicaux du Tchad : utilisation des méthodes statistiques

In der tropischen Bodenkette von Mindera (Tschad) konnten verschiedene pedologische und geochemische Faziestypen festgestellt werden. Von den höher gelegenen ausgewaschenen Typen zu den angereicherten Typen der tieferen Lagen findet man Kaolinit, konkretionierte Eisen-und Manganhydroxyde, Montmorillonit und schliesslich Kalziumkarbonat. Mit Hilfe statistischer Methoden ist es möglich die Proben in Gruppen zusammenzufassen, die Beziehungen zwischen Hauptund Spurenelementen festzustellen sowie deren Lokalisation in verschiedenen mineralogischen und geochemischen Faziestypen zu erkennen. So erscheint die landschaftliche Verteilung der Elemente sehr nuanciert : die Zusammensetzung der Bestandteile eines Faziestyps ist nicht konstant längs der Bodenkette, die relative Mobilität der Elemente hängt von dieser Fazies und den vorhandenen geochemischen Schranken ab.Геохимия последовательного ряда тропических почв чада. применение статистических методов. В ряде тропических почв Миндеры, территория Чад, различные педологические и геохимические фации располагаются, во времени и пространстве, в определенном порядке. Они характеризуются, от вышележащей выщелоченной до нижележащей замкнутой среды, следующим последовательним рядом : каолинит, конкреционные гидроокиси железа и потом марганца, монтмориллонит и карбонат кальция. Статистические методы (кистевой анализ, факторный анализ) позволяют выделить группы образцов, связь между главными элементами и микроэлементами, также как и их локализацию в различных минералогических и геохимических определенных фациях. Таким образом, хроматографическая схема элементов в ландшафтах представляется нюансированной : состав компонентов одной фации не постоянен в последовательном ряду ; порядок относительной подвижности элементов меняется в зависимости от фаций и природы геохимических барьеров.In the tropical soil catena of Mindera, Chad, several pedological faciès are distributed in space and time. From the leached environments of the upper part of the catena to the confined environments of the lower part, the succession is the following : kaolinite, iron then manganese hydroxide concretions, montmorillonite and calcium carbonate. The statistic methods (factor analysis and cluster analysis) permit the autours to establish groups of samples, relations between major elements and trace elements, as well as their distribution in the different mineralogical and geochemical facies defined. The scheme of the chromatography of elements in the landscapes is thus discriminative : the composition of the constituents of a facies is not constant along the catena ; the order of relative mobility of elements varies as a function of facies and of the nature of geochemical barriers.Dans la chaîne de sols tropicaux de Mindera, au Tchad, différents faciès pédologiques et géochimiques s'ordonnent dans l'espace et dans le temps. Ils sont caractérisés, depuis les milieux lessivés de l'amont aux milieux confinés de l'aval, par la succession suivante : kaolinite, hydroxydes concrétionnés de fer puis de manganèse, montmorillonite et carbonate de calcium. Les méthodes statistiques (analyse de grappe et analyse factorielle) permettent d'établir des groupes d'échantillons, les relations entre éléments majeurs et traces, ainsi que leur localisation dans les différents faciès minéralogiques et géochimiques définis. Le schéma de la Chromatographie des éléments dans les paysages est donc nuancé : la composition des constituants d'un faciès n'est pas constante le long de la toposéquence ; l'ordre de mobilité relative des éléments varie en fonction des faciès et de la nature des barrières géochimiques.Karpoff Anne-Marie, Bocquier Gérard, Isnard Pierre, Tardy Yves. Géochimie d'une toposéquence de sols tropicaux du Tchad. Utilisation des méthodes statistiques. In: Sciences Géologiques. Bulletin, tome 26, n°4, 1973. Sédimentologie et géochimie de la surface. pp. 315-338

Development of automated tools based on electronic identification for the improvement of organic livestock production systems

Technical constraints of livestock production in organic farming systems are numerous and require more attention than in conventional systems. The implementation of individual electronic identification that is planned in Europe offers the possibility of developing automated devices that may be well adapted to the practices of organic breeders. We developed an automated mounting detector, carried by a male, which makes it possible to detect any female in oestrus. Hence, this device is the unique solution for inseminating females when they are fertile, thus ensuring links with selection programmes. The second device developed is a dynamic sorting door based on respect for animal behaviour, preventing stress by allowing animals not to be unnecessarily confined. When associated with an electronic weighing device, it offers the possibility of adapting health treatments to the appropriate animals, in agreement with organic breeding specifications. Finally, electronic identification combined with GPS offers the breeder the possibility of simplifying the certification of animals in areas converted to organic farming. We believe that these technologies may greatly reduce the workload of breeders while improving animal welfare

Do adult health outcomes in urban population reflect local health risk? A matched cohort analysis of migration effects in Ouagadougou, Burkina Faso

Background Selective migration may affect health indicators in both urban and rural areas. Sub-Saharan African urban areas show evidence of both negative and positive selection on health status at outmigration. Health outcomes as measured in urban populations may not reflect local health risks and access to health services. Methods Using the Ouagadougou Health and Demographic Surveillance System and a migrant followup survey, we measured differences in health between matched non-migrants and outmigrants. We applied Cox and competing risks models on migration and death. Results Controlling for premigration health status, migrants who moved out of Ouagadougou have higher mortality (HR 3.24, 95%CI 1.23 to 8.58) than non-migrants and migrants moving to other Ouagadougou areas. However, these effects vanish in the matched sample controlling for all interactions between death determinants. These and other results show little evidence that migration led to higher mortality or worse health. Conclusions Health outcomes as measured in Ouagadougou population do reflect local health risks and access to health services despite high migration intensity. However, neither the hypothesis of effect of health on migration nor the hypothesis of negative effect of migration on health or survival was confirmed

Modeling Spanish anxiolytic consumption: Economic, demographic and behavioral influences

Anxiolytics (AX) are the psychotropic drugs prescribed for the treatment of anxiety and insomnia for 2–4 weeks, for longer periods of consumption (>1 month) may lead to the development of tolerance or addiction. In fact, its prescription was 16% of the total pharmaceutical expenditure in Spain in 2007. This paper deals with the development of a mathematical model describing the dynamic of the addiction to AX for the case study of the Spanish region of Castellón. The reasons believed to cause the development of addicts to AX are the economic situation, the marriage termination and the social contact. The simulations performed to forecast the addicts rate for the period 2010–2014 showed an increase from 6% in 2010 to 14% in 2014 with a fluctuation of about 2% between the possible economic scenarios. Finally, the analysis of sensitivity of the rate of addicts to the fluctuation of the social contact parameters was performed, letting us estimate its impact on the pharmaceutical expenditure.De La Poza, E.; Guadalajara Olmeda, MN.; Jódar Sánchez, LA.; Merello Giménez, P. (2013). Modeling Spanish anxiolytic consumption: Economic, demographic and behavioral influences. Mathematical and Computer Modelling. 57(7):1619-1624. https://doi.org/10.1016/j.mcm.2011.10.020S1619162457

A Synthesis of Global Urbanization Projections

This chapter reviews recent literature on global projections of future urbanization, covering the population, economic and physical extent perspectives. We report on several recent findings based on studies and reports on global patterns of urbanization. Specifically, we review new literature that makes projections about the spatial pattern, rate, and magnitude of urbanization change in the next 30–50 years. While projections should be viewed and utilized with caution, the chapter synthesis reports on several major findings that will have significant socioeconomic and environmental impacts including the following: By 2030, world urban population is expected to increase from the current 3.4 billion to almost 5 billion; Urban areas dominate the global economy – urban economies currently generate more than 90 % of global Gross Value Added; From 2000 to 2030, the percent increase in global urban land cover will be over 200 % whereas the global urban population will only grow by a little over 70 %. Our synthesis of recent projections suggest that between 50%–60% of the total urban land in existence in 2030 will be built in the first three decades of the 21st century. Challenges and limitations of urban dynamic projections are discussed, as well as possible innovative applications and potential pathways towards sustainable urban futures