Factors influencing the dissolution of phosphate rock in a range of high P-fixing soils from Cameroon

A laboratory incubation experiment was conducted to evaluate the soil factors that influence the dissolution of two phosphate rocks (PRs) of different reactivity (Gafsa, GPR, reactive PR; and Togo-Hahotoe, HPR, low reactivity PR) in seven agricultural soils from Cameroon having variable phosphorus (P)- sorption capacities, organic carbon (C) contents, and exchangeable acidities. Ground PR was mixed with the soils at a rate of 500 mg P kg 21 soil and incubated at 30 degrees C for 85 days. Dissolution of the PRs was determined at various intervals using the Delta NaOH-P method ( the difference of the amount of P extracted by 0.5 M NaOH between the PR-treated soils and the control). Between 4 and 27% of HPR and 33 and 50% of GPR were dissolved in the soils. Calcium (Ca) saturation of cation exchange sites and proton supply strongly affected PR dissolution in these soils. Acid soils with pH-(H2O), < 5 (NKL, ODJ, NSM, MTF) dissolved more phosphate rock than those with pH-(H2O) > 5 (DSC, FGT, BAF). However, the lack of a sufficient Ca sink in the former constrained the dissolution of both PRs. The dissolution of GPR in the slightly acidic soils was limited by increase in Ca saturation and that of HPR was constrained by limited supply in protons. Generally, the dissolution of GPR was higher than that of HPR for each soil. The kinetics of dissolution of PR in the soils was best described by the power function equation P At B. More efficient use of PR in these soils can be achieved by raising the soil cation exchange capacity, thereby increasing the Ca sink size. This could be done by amending such soils with organic materials.

Les Français sous les bombes alliées, 1940-1945

Plus de 517 000 tonnes de bombes sont déversées sur l’Hexagone par les alliés entre 1940 et 1945, soit près de sept fois plus que le total largué sur le Royaume-Uni par la Luftwaffe. Plus de 57 000 Français en sont morts, dont plus de 38 000 au cours de la seule année 1944. Cet aspect fondamental de l’histoire des années noires, que les survivants et les familles des victimes ne connaissent que trop bien, et qui a fait l’objet de nombreuses études locales, est encore relativement marginalisé de la « grande histoire » de l’Occupation et de la Libération. Pourquoi et comment les armées aériennes alliées ont-ils attaqué la France ? Quelles mesures ont été prises par le gouvernement de Vichy pour protéger les populations ? Comment les Alliés ont-ils justifié les attaques auprès des Français, et comment la propagande vichyssoise a-t-elle essayé de les mettre à profit ? Comment les populations civiles ont-ils vécu les bombardements, et comment se sont-elles mobilisées pour se défendre ? Comment la Résistance a-t-elle réagi à des attaques qui ne pouvaient que nuire à son audience au sein des Français, ainsi qu’à celle des « Anglo-saxons » ? Autant de questions auxquelles l’ouvrage comme le documentaire répondent, avec l’appui de documents d’archives britanniques et françaises, mais aussi de témoignages nombreux et émouvants.

Parental responsibility beliefs: associations with parental anxiety and behaviours in the context of childhood anxiety disorders

Background: High levels of parental anxiety are associated with poor treatment outcomes for children with anxiety disorders. Associated parental cognitions and behaviours have been implicated as impediments to successful treatment. We examined the association between parental responsibility beliefs, maternal anxiety and parenting behaviours in the context of childhood anxiety disorders. Methods: Anxious and non-anxious mothers of 7-12 year old children with a current anxiety disorder reported their parental responsibility beliefs using a questionnaire measure. Parental behaviours towards their child during a stressor task were measured. Results: Parents with a current anxiety disorder reported a greater sense of responsibility for their child’s actions and wellbeing than parents who scored within the normal range for anxiety. Furthermore, higher parental responsibility was associated with more intrusive and less warm behaviours in parent-child interactions and there was an indirect effect between maternal anxiety and maternal intrusive behaviours via parental responsibility beliefs. Limitations: The sample was limited to a treatment-seeking, relatively high socio-economic population and only mothers were included so replication with more diverse groups is needed. The use of a range of stressor tasks may have allowed for a more comprehensive assessment of parental behaviours. Conclusions: The findings suggest that parental anxiety disorder is associated with an elevated sense of parental responsibility and may promote parental behaviours likely to inhibit optimum child treatment outcomes. Parental responsibility beliefs may therefore be important to target in child anxiety treatments in the context of parental anxiety disorders.