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Since its invasion in late 2016, the fall armyworm has a widespread year-round distribution within Africa where it continues to threaten cereal production, particularly maize. Most recommended control advice emphasises the need for interventions against larvae early after colonization of a new maize crop by adults followed by a later intervention if an infestation persists. The current times for action are approximate action thresholds based on scouting which are difficult to implement as early development stages are cryptic and farmers, especially smallholders, have limited time for crop assessments. To improve the impact of controls, the modelling of early and late instar larval population emergence and development in relation to physiological time from planting was developed to enable times to action to be predicted and conveyed to farmers. The two larval population emergence models were built from field fall armyworm data from maize in Zambia and validated from similar data from multiple maize sites in Kenya. A component was included in the models to allow synchronization of maize emergence with larval development. Physiological time, in degree-days, was estimated using Earth Observation land surface temperature data sets. As precise information on action thresholds is lacking for Africa, recent published data on thresholds based on economic injury levels from Colombia were used as a guide but the models can be updated when new information becomes available for Africa. The practical implementation of the models in Africa is discussed including the outcome of some recent preliminary trials with maize farmers in Kenya. • Phenology models were developed for Fall Armyworm larvae populations in Africa. • These enable advanced alerts to be sent to farmers for optimum time for controls. • The models incorporate continuous breeding and larval population growth. • The models were built from field data from Zambia and validated in Kenya. • The models are driven by real-time EO data on land surface temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Several novel series of nitrile-containing fluoroquinolones with weakly basic amines are reported which have reduced potential for hERG (human ether-a-go-go gene) channel inhibition as measured by the dofetilide assay. The new fluoroquinolones are potent against both Gram-positive and fastidious Gram-negative strains, including Methicillin resistant Staphylococcus aureus and fluoroquinolone-resistant Streptococcus pneumoniae. Several analogs also showed low potential for human genotoxicity as measured by the clonogenicity test. Compounds 22 and 37 (designated PF-00951966 and PF-02298732, respectively), which had good in vitro activity and in vitro safety profiles, also showed good pharmacokinetic properties in rats. [Copyright &y& Elsevier]

Abstract: Lipid A is an essential component of the Gram negative outer membrane, which protects the bacterium from attack of many antibiotics. The Lipid A biosynthesis pathway is essential for Gram negative bacterial growth and is unique to these bacteria. The first committed step in Lipid A biosynthesis is catalysis by LpxC, a zinc dependent deacetylase. We show the design of an LpxC inhibitor utilizing a robust model which directed efficient design of picomolar inhibitors. Analysis of physiochemical properties drove design to focus on an optimal lipophilicity profile. Further structure based design took advantage of a conserved water network over the active site, and with the optimal lipophilicity profile, led to an improved LpxC inhibitor with in vivo activity against wild type Pseudomonas aeruginosa. [Copyright &y& Elsevier]