New Dihydroalkylhexenones from Lannea edulis

Activity-guided isolation of radical-scavenging compounds from the dichloromethane extract of the root bark of Lannea edulis led to isolation of two known bioactive alkylphenols [cardonol 7 (1) and cardonol 13 (2)], and three new dihydroalkylhexenones were also isolated (3-5). Their structures were elucidated by spectroscopic and chemical methods. The absolute configuration of 4 was determined by the Mosher ester method

The development of an economic model of arable, agroforestry and forestry systems

International audienceA computer-based economic model of arable, forestry and silvoarable systems was developed as part of the ‘Silvoarable Agroforestry for Europe’ project. The process of developing the model is described in terms of: the model background and purpose, the systems modelled, the objective of the economic analysis, the viewpoint of the analysis, the spatial and temporal scales, the generation and use of biophysical data, the model platform and interface, and the inputs and outputs. The objectives of the economic analysis are to compare silvoarable, arable and forestry systems at a one-hectare scale, and to determine the feasibility of silvoarable systems at a farm-scale. At a one-hectare scale, a partial budget is used to undertake a discounted cost-benefit analysis. The farm-scale analysis allows for heterogeneous land types, multiple enterprises on each land type, phased planting, and farm fixed costs. The model runs on an annual time step and requires biophysical data. It operates in a commonly available spreadsheet and works in different European language versions of the software. The description of the model and the process of development should be useful for future users and those embarking on their own modelling projects. This research was carried out as part of the SAFE (Silvoarable Agroforestry for Europe) collaborative research project. SAFE is funded by the EU under its Quality of Life programme, contract number QLF5-CT-2001-00560, and the support is gratefully acknowledged

Prenylated Isoflavonoids from the Root Bark of Erythrina vogelii

Four new prenylated isoflavonoids, vogelins D-G (1-4), were isolated from the CH2Cl2 extract of Erythrina vogelii root bark in addition to the known compounds isolupalbigenin (5), ficuisoflavone (6), ulexone (7), isochandalon (8), and isoderrone (9). The structures 1-4 were elucidated by spectroscopic and chemical methods. The absolute configuration of compound 1 was determined on the basis of its CD spectrum. Possible biogenetic relationships among the E. vogelii isoflavonoids are briefly discussed

Développement et utilisation d'une grille d'analyse pour caractériser les modèles d'économie en agroforesterie

Correspondance: [email protected]; fax: +44-1525-863344)International audienceA review of existing computer models of silvoarable1 economics was undertaken for a project, entitled Silvoarable Agroforestry for Europe (SAFE), which aims to reduce uncertainty regarding the introduction and management of silvoarable systems in Europe. Because the published literature describing and comparing such models is sparse, a framework was developed and then used to characterise five computer models: POPMOD, ARBUSTRA, the Agroforestry Estate Model, WaNuLCAS, and the Agroforestry Calculator. Key characteristics described for each model were the background, systems modelled, objective of the economic analysis, economic viewpoint, spatial and temporal scales, generation and use of biophysical data, model platform and interface, and input requirements and outputs. Each of the models could produce a partial budget of the profitability of a silvoarable, arable, or forestry system at a one-hectare level using discounted costbenefit analysis. Whilst the research models undertook the analysis from a viewpoint of a generic farmer, models developed for decision-support also included appraisals from the perspectives of tenants, share-croppers, and participants in a joint-venture. The two farm-scale models, ARBUSTRA and the Agroforestry Estate Model, could also be used to examine the feasibility of silvoarable systems on an existing business, and to determine the effects of heterogeneous land types and phased planting. The framework allows users to identify the pertinent issues for selecting or developing a particular model

Taxiphyllin from Henriettella fascicularis

(2R)-alpha-(beta-D-Glucopyranosyloxy)-4-hydroxybenzeneaceto- nitrile (taxiphyllin) dihydrate, C14H17NO7.2H(2)O, is a naturally occurring cyanogenetic glycoside which has been isolated from Henriettella fascicularis (Sw.) C. Wright (Melastomataceae). Its structure is stabilized by a wealth of intermolecular O-H...O and O-H...N hydrogen bonds spun into a three-dimensional network. Further stabilization arises from an intramolecular O-H...O bond and weak intermolecular C-H...O interactions. The very anisotropic growth speeds of the basal pinacoids from methanol mirror a certain structural inhomogeneity

Incidence of paradoxical reactions in patients treated with tocilizumab for rheumatoid arthritis: Data from the French registry REGATE

International audienc