A universal method to assess the potential of phosphorus loss from soil to aquatic ecosystems

Background, aim, and scope  

Phosphorus loss from terrestrial to the aquatic ecosystems contributes to eutrophication of surface waters. To maintain the world's vital freshwater ecosystems, the reduction of eutrophication is crucial. This needs the prevention of overfertilization of agricultural soils with phosphorus. However, the methods of risk assessment for the P loss potential from soils lack uniformity and are difficult for routine analysis. Therefore, the efficient detection of areas with a high risk of P loss requires a simple and universal soil test method that is cost effective and applicable in both industrialized and developing countries.     

Degradation of poly(3-hydroxybutyrate), PHB,by bacteria and purification of a novel PHB depolymerase fromComamonas sp.

Bacteria capable of growing on poly(3-hydroxybutyrate), PHB, as the sole source of carbon and energy were isolated from various soils, lake water, activated sludge, and air. Although all bacteria utilized a wide variety of monomeric substrates for growth, most of the strains were restricted to degrade PHB and copolymers of 3-hydroxybutyrate and 3-hydroxyvalerate, P(3HB-co-3HV). Five strains were also able to decompose a homopolymer of 3-hydroxyvalerate, PHV. Poly(3-hydroxyoctanoate), PHO, was not degraded by any of the isolates. One strain, which was identified asComamonas sp., was selected, and the extracellular depolymerase of this strain was purified from the medium by ammonium sulfate precipitation and by chromatography on DEAE-Sephacel and Butyl-Sepharose 4B. The purified PHB depolymerase was not a glycoprotein. The relative molecular masses of the native enzyme and of the subunits were 45,000 or 44,000, respectively. The purified enzyme hydrolyzed PHB, P(3HB-co-3HV), and—at a very low rate—also PHV. Polyhydroxyalkanoates, PHA, with six or more carbon atoms per monomer or characteristic substrates for lipases were not hydrolyzed. In contrast to the PHB depolymerases ofPseudomonas lemoignei andAlcaligenes faecalis T₁, which are sensitive toward phenylmethylsulfonyl fluoride (PMSF) and which hydrolyze PHB mainly to the dimeric and trimeric esters of 3-hydroxybutyrate, the depolymerase ofComamonas sp. was insensitive toward PMSF and hydrolyzed PHB to monomeric 3-hydroxybutyrate indicating a different mechanism of PHB hydrolysis. Furthermore, the pH optimum of the reaction catalyzed by the depolymerase ofComamonas sp. was in the alkaline range at 9.4.     

CDM Projects under the Kyoto Protocol: A Methodology for Sustainability Assessment – Experiences from South Africa and Uruguay

Under the Clean Development Mechanism (CDM) of the Kyoto Protocol, industrialised countries may finance greenhouse gases mitigation projects in developing countries. The Kyoto Protocol explicitly requires that the CDM shall assist developing countries to achieve sustainable development. However, a clear definition of sustainability for CDM projects is still debatable. MATA-CDM (Multi-Attributive Assessment of CDM Projects) is an approach that facilitates a quantitative assessment of potential projects regarding their contribution to sustainable development. This paper presents applications of MATA-CDM in two different countries. In South Africa, the application was done mainly for academic and demonstrative purposes, whereas in Uruguay it was implemented together with the responsible Designated National Authority (DNA). The work in both countries included the selection of sustainability criteria and measurable indicators. Experts weighted the criteria using personal interviews and a multi-stakeholder workshop. This method was applied to three potential CDM projects in South Africa and one in Uruguay. Results show that under the conditions of this study, the MATA-CDM approach yet fails to yield a perfect quantitative overall sustainability assessment of CDM projects but that several findings could be useful to further develop the approach with the aim to translate the vague term sustainable development to a mainstream project level. Valuable experience was in particular collected with different stakeholder processes to perform criteria weighting.     

Job satisfaction: a meta‐analysis of stabilities

Evidence suggesting that job satisfaction is caused by individual dispositions is reviewed, and stability coefficients for job satisfaction in previous studies are analysed with a meta‐analytic procedure. Previous longitudinal studies analysing job changer samples imply an upper limit estimate of 0.51 for direct dispositional influences on job satisfaction. A study of job changers considering the stability of working conditions suggests that this estimate has to be considerably corrected downwards. At present, it is concluded that it is more likely that dispositions indirectly affect job satisfaction via selection and self‐selection processes. Implications for job satisfaction as a tool for organizational assessment are discussed. Copyright © 2001 John Wiley & Sons, Ltd.     

Prenatal diagnosis of SMPD4 loss - A neurodevelopmental disorder with microcephaly,arthrogryposis and structural brain anomalies

SMPD4 loss is a rare neurodevelopmental disorder that leads to severe mental and physical disability and early death in infancy. Most cases of this genetic condition have been diagnosed postnatally. This article focuses on the prenatal findings of affected fetuses. The phenotypes can include growth restriction, arthrogryposis (clenched hands, foot deformity), as well as cerebral abnormalities (simplified gyral pattern/lissencephaly, cerebellar hypoplasia, corpus callosum deformity). SMPD4 loss is detectable via exome sequencing. Here, two fetuses displayed a homozygotic pathogen variant in the SMPD4 gene, encoding for the enzyme Sphingomyelinase-4. Both parents were heterozygous carriers of the pathogenic variant. On detection of the above mentioned signs exome sequencing is indicated, with focus on the SMPD4 gene.