Risks of risk decisions

The analytical approaches utilized for evaluating the acceptability of technological risk originate from analogies to financial cost-benefit risk analysis. These analogies appear generally valid for viewing risk from a societal basis, but are not applicable to individual risk assessments. Conflicts arising from these different views of risk assessment provide insights to the origins of individual, intuitive evaluations. Societal risk decisions made under conflict represent political compromises, and the resulting decision process creates substantial conflict costs. The pragmatic use of quantitative risk criteria (safety targets) may be useful in reducing these costs.     

Relationship between Nitrogen Use Efficiency and Response Index in Winter Wheat

Although nitrogen use efficiency (NUE) of small grains is well documented at 33% worldwide, there has been little research relating NUE to yield factors. This study examined the relationship between NUE and the response index at harvest (RI_HARVEST) of winter wheat (Triticum aestivum L.). Yield data from a long-term fertility study established at Lahoma, Oklahoma in 1971 was used to explore the relationship. In this report, six nitrogen (N) rates at non-limiting levels of P and K were evaluated. Regression analysis showed a positive relationship between NUE and RI_HARVEST for all years across all N rates (r² = 0.37). But this relationship was improved (r² = 0.45) when both RI_NDVI and RI_HARVEST were included in the model. The linear relationship between NUE and RI_HARVEST was significantly improved, when yield data and corresponding NUE were separated according to the annually applied fixed N rate. As the N rate increased the resulting slope of the relationship between NUE and RI was reduced. These analyses also demonstrate that temporal variability in NUE exists and that NUE can be predicted.     

Cilia and cilia-related disorders

Abstract

Extract

Among the puzzling aspects of the recently described autosomal recessive polycystic kidney disease (ARPKD) of sheep (Johnstone et al 2005 Johnstone, AC, Davidson, BI, Roe, AR, Eccles, MR and Jolly, RD. 2005. Congenital polycystic kidney disease in lambs. New Zealand Veterinary Journal, 53: 307–314. [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) is the multiplicity of organ systems affected and the phenotypic variations that occur between the various animal species. It has been shown in studies of other inherited polycystic kidney disease syndromes that the normal gene products of a mutant are likely to be involved in ciliary structure and function. The studies that have led to this recognition can be expected to eventually provide the basis for a better understanding of the functioning of this organelle, and the pathogenesis of lesions in the related diseases.

It is well known that cilia are important in the perception of light, olfactory stimuli and sound and that motile cilia provide cell motility (e.g. sperm) and transport of mucus and other fluids. Recent research has indicated that the involvement of the primary cili-um/basal body complex is of central importance in the detection and cellular response to extracellular movement of fluid, critical phases of embryonic development, cell cycle regulation and maintenance of cell polarity.

Confocal microscopic studies of renal cyst epithelium in ovine ARPKD have shown that only 30% of cells have a cilium and that these are often truncated (McGlashan et al 2005 McGlashan, SR, Poole, CA, Stayner, C, Johnstone, AC, Eccles, MR and Jensen, CG. 2005. “Primary cilia in fibrosis associated with two models of polycystic kidney disease”. In Proceedings of the 45th Annual Conference of the American Society for Cell Biology December 10–14 [Google Scholar]). The observation, although preliminary, strongly supports the argument that the mutant gene in this disease of sheep normally encodes for a protein essential for primary ciliary function.     

Effects of <Emphasis Type="Italic">Acacia seyal</Emphasis> and biochar on soil properties and sorghum yield in agroforestry systems in South Sudan

We studied the effects of Acacia seyal Del. intercropping and biochar soil amendment on soil physico-chemical properties and sorghum (Sorghum bicolor L.) yields in a two-year field experiment conducted on a silt loam site near Renk in South Sudan. A split-plot design with three replications was used. The main factor was tree-cropping system (dense acacia + sorghum, scattered acacia + sorghum, and sole sorghum) and biochar (0 and 10 Mg ha^?1) was the subplot factor. The two acacia systems had lower soil pH, N and higher C/N ratios compared to the sole sorghum system. Biochar significantly increased soil C, exchangeable K⁺ contents, field capacity and available water content, but reduced soil exchangeable Ca²⁺ and effective CEC, and had no effect on soil pH. Acacia intercropping significantly reduced sorghum grain yields while biochar had no significant effect on sorghum yields. The land equivalent ratio (LER) for sorghum yield was 0.3 for both acacia systems in 2011, with or without biochar, but increased in 2012 to 0.6 for the scattered acacia system when combined with biochar. The reduction in sorghum yields by the A. seyal trees was probably due to a combination of competition for water and nutrients and shading. The lack of a yield response to biochar maybe due to insufficient time or too low a dosage. Further research is needed to test for the effects of tree intercropping and biochar and their interactions on soil properties and crop yields in drylands.     

Identification of a new Escherichia coli She haemolysin homolog in avian E. coli

Haemolysin is one type of virulence factor that assists in the pathogenesis of Escherichia coli. Currently, hemolytic activity in E. coli has been attributed to haemolysin genes found in either uropathogenic or enterohemorrhagic E. coli. Both haemolysins are classified as RTX toxins because they both have repeats in toxin domains and share similar operon organization, sequence homology, and mechanisms of action. Haemolytic avian E. coli isolates, however, lack either E. coli haemolysin gene. To investigate the avian E. coli haemolysin, a genomic library was made from an avian pathogenic E. coli. A haemolytic clone that was isolated was shown to contain homology with sheA, an E. coli K- 12 gene which causes haemolysis when present in high copy number. The cloned haemolysin gene, hlyE, lacked the conserved amino acid sequence and accessory genes common to all RTX toxins. DNA hybridizations and polymerase chain reaction amplifications showed that the nucleotide sequences homologous to hlyE were not present in a collection of three O157: H7 E. coli, five haemolytic canine uropathogenic E. coli, one haemolytic O26 E. coli, and three haemolytic avian pathogenic E. coli. Thus we have identified a new E. coli haemolysin distinct from the RTX haemolysins and have shown that some avian pathogenic E. coli possess a haemolysin with no apparent homology to hlyE or RTX haemolysins.     

Serum sickness in a dog associated with antivenin therapy for snake bite caused by Crotalus adamanteus

Objective: This case report describes antivenin‐associated acute and delayed hypersensitivity reactions in a dog envenomated by an Eastern diamondback rattlesnake (Crotalus adamanteus), specifically reviewing the syndrome of antivenin‐associated serum sickness. Clinician awareness of this syndrome is important in order to allow for its recognition and appropriate treatment. Case summary: A Boxer dog was envenomated by an Eastern diamondback rattlesnake. Shock, echinocytosis, and coagulopathy were manifested, and the dog was given antivenin crotalidae polyvalent therapy and supportive care. The early onset of an anaphylactoid reaction was attributed to antivenin therapy and was managed with diphenhydramine and subcutaneous epinephrine therapy. Fever, chemosis, and limb edema occurred during the 3rd through 6th hospital days following antivenin therapy and were consistent with serum sickness syndrome as described in humans. Further immunoassay support reflecting complement activation and response to treatment were characteristic. New information provided: To our knowledge, this describes the first reported case of antivenin‐associated serum sickness in a dog.