Mobilization of aluminium in soil by acid deposition and its uptake by grass cut for hay – a Chemical Time Bomb

Abstract. Analyses of soil and hay samples collected from the Park Grass Experiment at Rothamsted during the last 137 years indicate slow but significant increases in KCl- and EDTA-extractable aluminium in soil and a sudden and very large recent increase in the concentration of aluminium in the herbage. The latter is associated with a sudden increase in the rate of acidification of the soil over the last 10–15 years and the mobilization of aluminium as the soil enters the aluminium buffer range -a Chemical Time Bomb. Such severe acidification from atmospheric inputs on a well-buffered soil illustrates how quickly an apparently stable situation can change as a result of acid deposition. It highlights the need to protect soils and plants from the effects of acidification by decreasing acid inputs or by liming.     

THE PREVALENCE OF DIROFILARIA IMMITIS AND OTHER PARASITES IN URBAN POUND DOGS IN NORTH-EASTERN VICTORIA

SUMMARY The results of a survey investigating the prevalence of dirofilaria immitis and other helminth and protozoan infections in urban dogs in north-eastern Victoria are presented. D. immitis was detected in 2.7% of the general population (8.3% of dogs older than 2 years). Microfilariae of D. immitis were not detected in the peripheral circulation of 30% of dogs infected with the adult parasites. The most prevalent gastro-intestinal parasites were Dipylidium caninum 57%; Trichuris vulpis 41%; Toxocara canis 38%; and Uncinaria stenocephala 26%. The prevalence of T. canis in dogs less than one year of age was 73% and this decreased with increasing age. No Echinococcus granulosus adults were detected. Sarcocystis spp and Isospora ohioensis were the most commonly seen coccidians.     

Synthesis and structure of a terminal uranium nitride complex

The terminal uranium nitride linkage is a fundamental target in the study of f-orbital participation in metal-ligand multiple bonding but has previously eluded characterization in an isolable molecule. Here, we report the preparation of the terminal uranium(V) nitride complex [UN(Tren(TIPS))][Na(12-crown-4)(2)] {in which Tren(TIPS) = [N(CH(2)CH(2)NSiPr(i)(3))(3)](3-) and Pr(i) = CH(CH(3))(2)} by reaction of the uranium(III) complex [U(Tren(TIPS))] with sodium azide followed by abstraction and encapsulation of the sodium cation by the polydentate crown ether 12-crown-4. Single-crystal x-ray diffraction reveals a uranium-terminal nitride bond length of 1.825(15) angstroms (where 15 is the standard uncertainty). The structural assignment is supported by means of (15)N-isotopic labeling, electronic absorption spectroscopy, magnetometry, electronic structure calculations, elemental analyses, and liberation of ammonia after treatment with water.     

Waxy durum acts as a unique form of crumb softener in bread

Flour milled from waxy durum grain was incorporated into bread formulations and its effects on crumb softness and loaf volume compared to those of added fats and emulsifiers. Waxy durum had a small effect on increasing loaf volume, and little of this effect could be explained by dough height or oven spring; effects of most other additives were closely related to dough height or oven spring. For all additives, the relationship between crumb softness and loaf volume fitted a power law relationship. Waxy durum and some of the additives had a greater softening effect than predicted from their effect on volume while others produced a much firmer crumb. With only one exception, when combined with other additives waxy durum reduced compression of the crumb more than predicted on the basis of the effects on loaf volume of the additives alone. In common with some of the added lipids, during compression analysis, crumb prepared with waxy durum flour had similar levels of structural damage as crumb baked from the standard formulation; other lipids and emulsifiers produced more fragile crumb. Waxy durum flour appears to have unique effects on crumb softness.     

Preface—evaluating the response of critical zone processes to human impacts with sediment source fingerprinting

Journal of Soils and Sediments -