Partner choice and cooperation in social dilemmas can increase resource inequality

Cooperation is more likely when individuals can choose their interaction partner. However, partner choice may be detrimental in unequal societies, in which individuals differ in available resources and productivity, and thus in their attractiveness as interaction partners. Here we experimentally examine this conjecture in a repeated public goods game. Individuals (n = 336), participating in groups of eight participants, are assigned a high or low endowment and a high or low productivity factor (the value that their cooperation generates), creating four unique participant types. On each round, individuals are either assigned a partner (assigned partner condition) or paired based on their self-indicated preference for a partner type (partner choice condition). Results show that under partner choice, individuals who were assigned a high endowment and high productivity almost exclusively interact with each other, forcing other individuals into less valuable pairs. Consequently, pre-existing resource differences between individuals increase. These findings show how partner choice in social dilemmas can amplify resource inequality

Characterisation and application of NovaFiber lignin

Sulphur-free lignin coming from a novel alkaline-pulping process called NovaFiber, which has been developed by KIRAM AB, has been characterised and evaluated for potential applications. A Kraft lignin has been used for comparison. Considering the characterisation results of a NovaFiber softwood and Kraft lignin, it can be concluded that these lignins significantly differ in amounts of functional groups, molecular weight and acidity. This will affect their properties towards the potential applications studied in this project. The chemical composition and thermal stability to about 220degreesC of both types of lignin are comparable. The "high molecular" NovaFiber lignin is totally different from the other lignins due to a high ash content, as a result of the different precipitation procedure used. This study has shown that NovaFiber lignin has a great potential as functional additive for UV stabilisation of thermoplastics and as part of a phenol formaldehyde-based wood adhesive. Initial results demonstrate that NovaFiber and Kraft lignin act as UV stabilisers in polyethylene with comparable or only slightly inferior product performance, with respect to UV exposure, compared to a relatively very expensive commercially applied stabiliser (HALS). This means that NovaFiber lignin has a very good price/performance ratio. Without loss of adhesive strength, 31% of phenol formaldehyde can be replaced by NovaFiber and Kraft lignin in a wood adhesive. The adhesive properties have been improved to a level substantially higher than the phenol formaldehyde resin by using modified lignin, after sodium dithionite treatment, and/or by using a higher curing temperature. Furthermore, the processing of NovaFiber lignin is easier compared to Kraft lignin in respect of the mixing/solubility of the lignin in the thermoplastic or glue matrix and the amount of released odour seems to be much less. (C) 2004 Elsevier B.V. All rights reserved

Alpha-ketoamides as broad-spectrum inhibitors of coronavirus and enterovirus replication: structure-based design, synthesis, and activity assessment

The main protease of coronaviruses and the 3C protease of enteroviruses share a similar active-site architecture and a unique requirement for glutamine in the P1 position of the substrate. Because of their unique specificity and essential role in viral polyprotein processing, these proteases are suitable targets for the development of antiviral drugs. In order to obtain near-equipotent, broad-spectrum antivirals against alphacoronaviruses, betacoronaviruses, and enteroviruses, we pursued a structure-based design of peptidomimetic alpha-ketoamides as inhibitors of main and 3C proteases. Six crystal structures of protease-inhibitor complexes were determined as part of this study. Compounds synthesized were tested against the recombinant proteases as well as in viral replicons and virus-infected cell cultures; most of them were not cell-toxic. Optimization of the P2 substituent of the alpha-ketoamides proved crucial for achieving near-equipotency against the three virus genera. The best near-equipotent inhibitors, 11u (P2 = cyclopentylmethyl) and 11r (P2 = cyclo-hexylmethyl), display low-micromolar EC50 values against enteroviruses, alphacoronaviruses, and betacoronaviruses in cell cultures. In Huh7 cells, 11r exhibits three-digit picomolar activity against the Middle East Respiratory Syndrome coronavirus

Middle East Respiratory Syndrome Coronavirus (MERS-CoV): Announcement of the Coronavirus Study Group

Molecular basis of virus replication, viral pathogenesis and antiviral strategie

Avocado Fruit Quality Management during the Postharvest Supply Chain

Avocados are a popular subtropical fruit of high economic importance, and the European Union is the biggest importer of the bulk of the fruit coming from countries such as South Africa, Chile, and Israel. The fruit is highly nutritious, being rich in vitamins A, B, C, minerals, potassium, phosphorus, magnesium, iron, and antioxidants. The biggest challenge is that the fruit is highly susceptible to qualitative and quantitative postharvest losses. Successful maintenance of avocado fruit quality during the supply chain depends on many aspects, including adequate orchard management practices, harvesting practices, packing operations, postharvest treatments, temperature management, transportation and storage conditions, and ripening at destination. Postharvest losses are mostly attributed to flesh softening, decay, physiological disorders, and improper temperature management. Management of the supply chain is solely done to provide the fruit with the most favorable conditions to extend storage life, and retain quality and nutritional attributes of the fruit. The focus of this review is therefore to study the findings that have emanated from research done to retain overall avocado fruit quality and to reduce postharvest losses during the supply chain through the adoption of appropriate and novel postharvest technologies.Post-Harvest Innovation Programme (Fresh Produce Exporter Forum, South Africa, and Department of Science and Technology).http://www.tandfonline.com/loi/lfri202015-06-30hb201