Promoting ecological restoration in France: issues and solutions

Ecological restoration has developed greatly over recent decades. Promoting harmonious relationships between scientists and practitioners, between restoration ecology and ecological restoration, is essential to improving restoration projects. These relationships are difficult to achieve at a global scale, although international action remains essential. Therefore, regional and national networks are attempting to take up the challenge. With several European countries planning to create their own network in the coming years, insights from current practice are helpful. Here, we (1) describe the context in which ecological restoration is developing in France and (2) present the French restoration network, Réseau d'Echanges et de Valorisation en Ecologie de la Restauration (REVER). Most public policies related to restoration in France are derived from European Union (EU) directives, such as those on water, ecological networks, biodiversity, and protected species and natural habitat. Restoration can also be undertaken through Environmental Impact Assessment (EIA) or subsequent to damage. Following the model of the International Society for Ecological Restoration, the French network for ecological restoration (REVER) aims at accompanying and promoting restoration by facilitating relationships between the various stakeholders: practitioners, scientists, site managers, etc. To encourage exchange of knowledge and experience, REVER manages a website, organizes workshops, and provides links with SER‐Europe and Society for Ecological Restoration International (SERI). This article provides information that will be of interest to other countries trying to meet the Aichi targets of the convention on biological diversity: the restoration of 15% of degraded ecosystems by 2020.     

Trophoblast giant cell release of placental lactogens: temporal and regional characteristics

Placental lactogen (PL) production by rat trophoblast giant cells was studied using in vitro methods. The influence of trophoblast giant cell location within the conceptus and day of trophoblast giant cell isolation on the type of PL released in vitro were investigated. The effect of trophoblast giant cell location on the amount of PL, progesterone, and testosterone released in vitro was also evaluated. Trophoblast giant cells release two types of PLs in vitro; a high-molecular-weight lactogen, PL-1, and a low-molecular-weight lactogen, PL-2. The type of PL released by trophoblast giant cells was not influenced by their location within the conceptus at the time of dissection. Location did influence the amount of hormone produced by trophoblast giant cells. Mural trophoblast giant cells were more active in the production of PL, progesterone, and testosterone. The type of PL released by trophoblast giant cells is highly dependent upon the day of gestation the cells are removed for study. Trophoblast giant cells isolated on Day 10 of gestation release predominantly PL-1, while those cells isolated 24 hr later (Day 11 of gestation) release predominantly PL-2. The switch from PL-1 to PL-2 production that occurs in vivo does not occur under the in vitro conditions employed in this report.     

Soybean phosphatidylcholine vesicles containing plant sterols: a fluorescence anisotropy study

The typical plant sterols (sitosterol, stigmasterol and campesterol) were compared with respect to their ability to regulate membrane fluidity of soybean phosphatidylcholine (PC) vesicles. Fluidity changes were monitored by the steady-state fluorescence anisotropy with 1,6-diphenyl-1,3,5-hexatriene as a probe and assigned to a measure of the acyl chain orientational order. Sitosterol and campesterol appear to be the most suitable sterols in ordering the acyl chains of soybean lecithin bilayers, even more efficient than cholesterol, the standard of reference for sterol effects on membranes, suggesting that they play a significant role in the regulation of plant membrane properties. Stigmasterol is shown to be much less active. Cycloartenol, a biosynthetic precursor of plant sterols, increases the acyl chain order with the same efficiency as cholesterol. We also investigated the effects of two unusual sterols, 24-methylpollinastanol and 14 alpha,24-dimethylcholest-8-en-3 beta-ol, which were shown to accumulate in plants treated with fungicides belonging to two important classes, N-substituted morpholines and triazoles, respectively. These two sterols exhibit a behavior very similar to that of stigmasterol. The results are discussed in terms of sterol effects on the molecular packing of soybean PC bilayers.     

Analysis of zooplankton feeding experiments: some methodological considerations

Studies of the feeding ecology of zooplankton are noted morefor the problems associated with their quantitative analysesthan for their conclusions. In order to illustrate one particularlyinsidious problem, I use several more or less traditional methodsto obtain rather different results from experiments with themarine calanoid copepod Eucalanus pileatus and a variety ofphytoplankton. If the probabilities of encountering algal cellsof various taxa are proportional to their environmental frequencies,as is implicit in a feeding mechanism based upon improbableanalogy with a leaky sieve, E. pileatus seems to capture largecells more efficiently than small ones. If these frequenciesare weighted by the average cross-sectional areas of individualcells (i.e., those of spheres of equivalent volume), as wouldbe appropriate if they were intercepted (i.e., encountered)by single fibers (e.g., maxillary setae or setules), then E.pileatus seems to capture small cells more efficiently thanlarge ones. Inasmuch as these conflicting observations resultfrom different conceptions of the feeding mechanism, and sievingis only one of several reasonable alternatives that emerge fromthe relevant fluid dynamics, evidently the mechanism of feedingmust be elucidated before passive selection can be properlycharacterized. However, the feeding mechanism need not be understoodin order to study consumers whose behavior changes with therelative abundance of prey. I find that selectivity by E. pileatusvaries with algal concentration, and that large cells are consumeddisproportionately relative to their frequencies at high concentrations(in accord with results of other investigators), but that smallcells are consumed disproportionately relative to their encounterprobabilities (here a function of size as well as frequency,although other characteristics, such as scent and shape, maybe involved as well) irrespective of concentration. This observationis incompatible with the contemporary paradigm of zooplanktonfeeding, but it does not seem unreasonable considering the sizeand spatial distributions of particles in the ocean. Consequently,these results support the alternative hypothesis that consumersadapt to characteristics of the prey that they encounter mostfrequently.     

Novel cellulose derivatives. Part VI. Preparation and thermal analysis of two novel cellulose esters with fluorine-containing substituents

Two novel cellulose esters were prepared with fluorine (F)-containing substituents using homogeneous phase reaction chemistry in DMAc/LiCl. The partially substituted derivatives and their corresponding perpropionates proved to be thermoplastic polymers. The 2,2-difluoroethoxy and 2,2,3,3,4,4,5,5-octafluoropentoxy substituents were easily identified by ¹H- and ¹⁹F-NMR spectroscopy without disclosing their precise location on the anhydroglucose unit. Thermal analysis revealed modest or no crystallinity; glass transition temperatures between 53 and 113°C; and improved thermal stability as compared to their F-free counterparts.