Investigations into the toxicity of Echium plantagineum in sheep: 1. Field grazing experiments

A field grazing trial was undertaken to monitor the health and production of crossbred sheep grazing pasture where Echium plantagineum constituted a considerable proportion of the available forage. The trial, conducted for 19 months over successive grazing seasons, demonstrated a significant difference in production, with sheep on the E. plantagineum pasture being lighter and growing less wool compared with sheep on Echium-free pasture. No mortalities involving pyrrolizidine alkaloid poisoning were recorded in sheep grazing E. plantagineum, although there was histological evidence of moderately severe liver damage associated with high liver copper concentrations in at least one sheep following the grazing of large quantities of the plant.     

High-Tc superconductors in the two-dimensional limit:

The free modulation of interlayer distance in a layered high-transition temperature (high-Tc) superconductor is of crucial importance not only for the study of the superconducting mechanism but also for the practical application of high-Tc superconducting materials. Two-dimensional (2D) superconductors were achieved by intercalating a long-chain organic compound into bismuth-based high-Tc cuprates. Although the intercalation of the organic chain increased the interlayer distance remarkably, to tens of angstroms, the superconducting transition temperature of the intercalate was nearly the same as that of the pristine material, suggesting the 2D nature of the high-Tc superconductivity.     

Volatile compounds emitted by sclerotia of Sclerotinia minor,Sclerotinia sclerotiorum,and Sclerotium rolfsii

Volatile compounds emitted by sclerotia of Sclerotinia minor, Sclerotinia sclerotiorum, and Sclerotium rolfsii were identified by solid phase microextraction followed by gas chromatography and mass spectometry. Both S. minor and S. sclerotiorum emitted 2-methylenebornane and 2-methylisoborneol. In addition, S. minor emitted mesityl oxide, gamma-butyrolactone, cis- and trans-linalool oxide, linalool, and trans-nerolidol. S. sclerotiorum emitted 2-methyl-2-bornene, 1-methylcamphene, and a diterpene with a molecular weight of 272. Sclerotium rolfsii did not emit any of these compounds but did emit delta-cadinene and cis-calamenene. Chemicals emitted by S. minor and S. sclerotiorum were tested to determine if they could stimulate germination of conidia of Sporidesmium sclerotivorum, a mycoparasite on sclerotia of Sclerotinia spp. Chemicals were tested at 1 part per billion to 100 parts per million, both in direct contact with conidia and near, but not in, physical contact. None of the chemicals alone nor a combination of all chemicals induced germination of conidia of S. sclerotivorum.     

Thermochemistry and aqueous solubilities of hydrotalcite-like solids

Hydrotalcites are used in technology as catalysts and anion exchangers and are important sinks for environmental contaminants. Their compositional variability makes it important, but difficult, to estimate their aqueous solubility. We report calorimetric measurements of the heats of formation of cobalt-aluminum hydrotalcite phases. The heat and free energy of formation from the elements are equal to those of mechanical mixtures of binary compounds, namely hydroxides and carbonates. The interlayer anion is much more important than the cation in determining the solubility of the hydrotalcite phase and its ability to contain or release heavy metals to the environment. Because hydrotalcites do not have an unreactive polymer as a structural core, their aqueous stability will change dramatically with composition, particularly with anion content. This simple mechanical mixture model allows prediction of aqueous solubilities and trace metal retention in a variety of geochemical settings.     

The origin of aluminum flocs in polluted streams

About 240,000 square kilometers of Earth's surface is disrupted by mining, which creates watersheds that are polluted by acidity, aluminum, and heavy metals. Mixing of acidic effluent from old mines and acidic soils into waters with a higher pH causes precipitation of amorphous aluminum oxyhydroxide flocs that move in streams as suspended solids and transport adsorbed contaminants. On the basis of samples from nine streams, we show that these flocs probably form from aggregation of the epsilon -Keggin polyoxocation AlO4Al12(OH)24(H2O)12(7+)(aq) (Al13), because all of the flocs contain distinct Al(O)4 centers similar to that of the Al13 nanocluster.     

A review of Ireland's waterbirds,with emphasis on wintering migrants and reference to H5N1 avian influenza

Ireland is characterised by its diversity and large abundance of wetlands, making it attractive to a wide variety of waterbirds throughout the year. This paper presents an overview of Ireland's waterbirds, including ecological factors relevant to the potential introduction, maintenance, transmission and spread of infectious agents, including the H5N1 avian influenza virus, in Ireland. Particular emphasis is placed on five groups of wintering migrants (dabbling and sieving wildfowl, grazing wildfowl, diving wildfowl, waders and gulls), noting that the H5N1 avian influenza virus has mainly been isolated from this subset of waterbirds. Ireland's wetlands are visited during the spring and summer months by hundreds of thousands of waterbirds which come to breed, predominantly from southern latitudes, and during the autumn and winter by waterbirds which come from a variety of origins (predominantly northern latitudes), and which are widely distributed and often congregate in mixed-species flocks. The distribution, feeding habits and social interactions of the five groups of wintering migrants are considered in detail. Throughout Ireland, there is interaction between different waterbird populations (breeding migrants, the wintering migrants and resident waterbird populations). There is also a regular and complex pattern of movement between feeding and roosting areas, and between wetlands and farmland. These interactions are likely to facilitate the rapid transmission and spread of the H5N1 avian influenza virus, if it were present in Ireland.     

Survival and dispersal of a defined cohort of Irish cattle

An understanding of livestock movement is critical to effective disease prevention, control and prediction. However, livestock movement in Ireland has not yet been quantified. This study has sought to define the survival and dispersal of a defined cohort of cattle born in Co. Kerry during 2000. The cohort was observed for a maximum of four years, from January 1, 2000 to December 31, 2004. Beef and dairy animals moved an average 1.31 and 0.83 times, respectively. At study end, 18.8% of the beef animals remained alive on Irish farms, including 6.7% at the farm-of-birth, compared with 48.6% and 27.7% for dairy animals respectively. Beef animals werae dispersed to all Irish counties, but mainly to Cork, Limerick, Tipperary and Galway. Dairy animals mainly moved to Cork, Limerick, and Tipperary, with less animals going to Galway, Meath and Kilkenny. The four-year survival probability was 0.07 (male beef animals), 0.25 (male dairy), 0.38 (female beef), and 0.72 (female dairy). Although there was considerable dispersal, the number of moves per animal was less than expected.     

The prevalence and significance of hyperglycemia in hospitalized cats

Objective – To report the prevalence of hyperglycemia in cats admitted to a veterinary hospital and to determine if hyperglycemic cats had increased morbidity and mortality when compared with normoglycemic cats.
Design – Retrospective clinical study.
Setting – Community-based referral hospital.
Animals – Nondiabetic cats admitted to the hospital.
Interventions – None.
Measurements and Main Results – The medical records of nondiabetic cats admitted to the hospital over a 1-year period were reviewed. There were 182 cats that met the criteria for inclusion in the study. Information obtained included signalment, length of hospitalization, initial and highest blood glucose measurement, diagnosis, treatment, and final disposition. Sixty-three percent of cats (116/182) were hyperglycemic at the time of presentation. Total incidence of hyperglycemia at any point during hospitalization was 64% (118/182). No association was found between hyperglycemia either initially or at any point during the hospitalization and mortality. However, a significant association was documented between the presence of hyperglycemia and increased length of hospitalization (LOH) ( P =0.04). The duration of LOH was also significantly associated with the degree of hyperglycemia ( P =0.01). A number of different disease processes were represented in the study population. However, the number of cats in each disease category was small and no association could be found between any of them and blood glucose affecting mortality and morbidity.
Conclusion – The prevalence of hyperglycemia in feline patients admitted to a primary referral hospital was 64%. Cats with hyperglycemia had a longer LOH when compared with normoglycemic cats; however, presence of hyperglycemia did not impact mortality in this population of cats.