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Historically, subsistence farmers around the Atlantic coast of NW Europe utilized marine algae as a fertilizer in agroecosystems, a practice that continued in small areas and is now considered to have real potential for re-establishing sustainable food production systems on marginal soils. Earthworms form a significant component of soil fauna, and their ecosystem services are well-documented. Therefore, palatability of marine organic amendments to faunal detritivores of terrestrial systems is of interest. This work aimed to assess the potential for growth of Aporrectodea caliginosa, Lumbricus rubellus and Aporrectodea longa fed with two common macroalgae (seaweeds), Laminaria digitata and Fucus serratus. In addition, choice chambers were constructed to permit earthworm selection of these macroalgae with more conventional organic materials, horse manure (HM) and birch leaves (BL). Over a period of 2 months, earthworm species showed significantly greater mass gain with conventional food (p Laminaria outperformed Fucus, which in turn was superior to soil alone. Similarly, when given a choice, a significant preference (p A. caliginosa when offered seaweeds only. By contrast, L. rubellus and A. longa showed significant preferences (p Laminaria over Fucus and fresh material over degraded. These results underline an interest to profit from natural resources (seaweeds) to maintain or improve soil biological quality in marginal coastal areas.

International audience; This paper presents several models addressing optimal portfolio choice, optimal portfolio liquidation, and optimal portfolio transition issues, in which the expected returns of risky assets are unknown. Our approach is based on a coupling between Bayesian learning and dynamic programming techniques that leads to partial differential equations. It enables to recover the well-known results of Karatzas and Zhao in a framework à la Merton, but also to deal with cases where martingale methods are no longer available. In particular, we address optimal portfolio choice, portfolio liquidation, and portfolio transition problems in a framework à la Almgren–Chriss, and we build therefore a model in which the agent takes into account in his decision process both the liquidity of assets and the uncertainty with respect to their expected return.

On reclaimed landfill sites, the addition of organic matter such as composted green waste (CGW) to soil-forming materials can support tree survival and growth. CGW addition may also assist the establishment of sustainable earthworm populations, and in turn these organisms can promote further soil development through their burrowing and feeding activity. Despite such potentially mutual benefits, little research has been carried out into CGW and earthworm interactions with trees on reclaimed land. A twelve month, open field nursery experiment revealed the responses of the interactions between two tree species; Alnus cordata (Betulaceae) and Acer platanoides (Sapindaceae), CGW and the earthworms Aporrectodea longa (Lumbricidae) and Allolobophora chlorotica (Lumbricidae) in reclaimed soil. Controlled mesocosm conditions permitted a detailed investigation into the factors affecting tree growth and nutrient uptake, soil nutrient cycling and earthworm population dynamics. Results revealed that A. cordata growth was unaffected by CGW or earthworm addition. There was, however, a significant positive synergistic effect of earthworm activity and CGW addition on A. platanoides growth. CGW addition significantly increased levels of organic carbon and essential plant macro-nutrients in reclaimed soil while earthworm activity assisted decomposition of both leaf litter and CGW. Findings showed that CGW may serve as a suitable early source of organic matter to support earthworm population establishment on reclaimed sites. This experiment demonstrates that CGW improves reclaimed soil quality, thereafter supporting tree establishment and growth on reclaimed landfill.

Micro/nanostructures based naturally occurring building blocks have attracted much attention as potential materials in the field of bio-nanotechnology. In this context, peptides are ideal naturally occurring materials for tissue regeneration, scaffolding, and drug delivery. Herein we report an initial study of fabrication of spherical and tubular structures by self-assembly process using butoxy carbonyl (Boc)-diphenylalanine as a naturally occurring peptides under different solvent conditions in the presence and absence of superparamagnetic iron oxide (SPIONs) core. The novel nanocomposites have been characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) Thermogravimetric Analysis (TGA) and Magnetic Hyperthermia under Alternating Magnetic Field (AMF).

Background: The ecological importance of deadwood is widely acknowledged, however popular forestry practices may reduce deadwood from a site, and most European forests now fall below recommended targets, putting deadwood-associated species at risk. There is increasing evidence that earthworm species which live in alternative habitats such as deadwood can be missed by traditional sampling methods, which can lead to false classifications regarding species distributions and conservation status and value. Resolving the current lack of a systematic and quantitative methodology for surveying earthworms in microhabitats such as deadwood may therefore lead to valuable insights into earthworm species ecologies in forest ecosystems. The main aim of this research was to develop and trial a systematic method for surveying deadwood-associated earthworms, with potential future application to other invertebrates. Sampling of earthworms within soil, deadwood and soil beneath deadwood was carried out across a chronosequence of unmanaged oak forest stands. The results were then used to investigate the influence of soil and deadwood environmental factors and woodland age on the earthworm populations of oak-dominated broadleaf woodlands. \ud Results: Results from our surveys successfully show that in oak woodland habitats with deadwood, omitting deadwood microhabitats from earthworm sampling can lead to underestimates of total earthworm species richness, abundance and biomass. We also found a significantly greater proportion of juveniles within the earthworm communities of broadleaf deadwood, where temperature and moisture conditions were more favourable than surrounding open soil habitats. \ud Conclusions: The systematic method presented should be considered as additional and complementary to traditional sampling protocols, to provide a realistic estimate of earthworm populations in woodland systems. Adopting this quantitative approach to surveying the biodiversity value of deadwood may enable forest management practices to more effectively balance wood production against ecological and conservation values. Opportunities for further development of the sampling methodology are proposed.

When we observed earthworms (Lumbricus terrestris L.; the dew worm or nightcrawler), foraging on patchily distributed plant residues in the laboratory, we noticed an exceptional interaction in their acquisition of dead organic matter. We review this original observation and then relate a subsequent finding which indicates the importance of the phenomenon in the field.

To better understand the quantitative implications of human capital externalities at the aggregate level, we estimate a two-sector endogenous growth model with knowledge spill-overs. To achieve this, we account for trend growth in a model consistent fashion and employ a Markov-chain Monte-Carlo (MCMC) algorithm to estimate the model's posterior parameter distributions. Using U.S. quarterly data from 1964-2017, we find significant positive externalities to aggregate human capital. Our analysis further shows that eliminating this market failure leads to sizeable increases in education-time, endogenous growth and aggregate welfare.

This paper describes vermicomposting of kitchen organic waste with the use of Eisenia fetida earthworms in an ecological box. To control excessively proliferated Sciaridae in the box medium, an Owinema bio-preparation, which contains larvae of the nematode Steinernema feltiae, was used. The effect of this bioinsecticide on the earthworm population during vermicomposting of organic waste was assessed. It was found that the applied bio-preparation effectively limited the population of sciarids and also had a positive effect on the development of the earthworm population (it caused a significant increase in the number and biomass of mature and immature forms and cocoons produced (p &lt, 0.05)). The Owinema preparation also had a positive effect on the rate of organic waste vermicomposting.

We studied the soil community and habitat consequences of introducing a deep-burrowing, sedentary life-style earthworm, Lumbricus terrestris (dew-worm) into arable zero-till clay. Seventeen years after introduction, which was originally aimed at improving the macroporosity and permeability of the heavy clay soil, we returned to the gradient of L. terrestris dispersal (well established, more recent and no settlement) and investigated the temporal development of the ecosystem engineering impacts on different faunal groups (earthworms, enchytraeids and nematodes) and soil porosity. The faunal re- sponses were examined both at L. terrestris midden scale (individual living site) and field scale. We found that L. terrestris middens sustained elevated densities of all three faunal groups. In the case of earth- worms, there was evidence for temporal development of the engineering impact as the difference be- tween the midden and non-midden areas was more pronounced in the well-established areas than close to the leading edge of dispersal. The earthworm community composition was not altered at L. terrestris midden sites. The settlement of L. terrestris had no discernible effects on field-scale earthworm and nematode abundances, but enchytraeids were practically absent beyond the leading edge of the dispersal. This effect might, however, be partly explained by a gradient of increasing clay content. Soil macroporosity at L. terrestris midden sites did not increase with the age of L. terrestris settlement. Our results suggest that L. terrestris settlement in a clay soil can significantly increase the spatial patchiness of soil fauna, but may not, except in the case of enchytraeids, affect their field-scale abundances or the macroporosity of the soil in the vicinity of L. terrestris living sites.

Whilst the profiling of the transcriptome and proteome even of single-cells becomes feasible, the analysis of the translatome, which refers to all messenger RNAs (mRNAs) engaged with ribosomes for protein synthesis, is still an elaborate procedure requiring millions of cells. Herein, we report the generation and use of “smart materials”, namely molecularly imprinted polymers (MIPs) to facilitate the isolation of ribosomes and translated mRNAs from merely 1,000 cells. In particular, we show that a hydrogel-based ribosome imprinted polymer could recover ribosomes and associated mRNAs from human, simian and mice cellular extracts, but did not selectively enrich yeast ribosomes, thereby demonstrating selectivity. Furthermore, ribosome imprinted polymers enabled the sensitive measurement of an mRNA translational regulatory event, requiring 1,000-fold less cells than current methodologies. These results provide first evidence for the suitability of MIPs to selectively recover ribonucleoprotein complexes such as ribosomes, founding a novel means for sensitive detection of gene regulation.

Background\ud \ud Human embryonic stem cells (HESC) readily differentiate into an apparently haphazard array of cell types, corresponding to all three germ layers, when their culture conditions are altered, for example by growth in suspension as aggregates known as embryoid bodies (EBs). However, this diversity of differentiation means that the efficiency of producing any one particular cell type is inevitably low. Although pancreatic differentiation has been reported from HESC, practicable applications for the use of β-cells derived from HESC to treat diabetes will only be possible once techniques are developed to promote efficient differentiation along the pancreatic lineages.\ud \ud \ud Methods and Findings\ud \ud Here, we have tested whether the transcription factor, Pax4 can be used to drive the differentiation of HESC to a β-cell fate in vitro. We constitutively over-expressed Pax4 in HESCs by stable transfection, and used Q-PCR analysis, immunocytochemistry, ELISA, Ca2+ microfluorimetry and cell imaging to assess the role of Pax4 in the differentiation and intracellular Ca2+ homeostasis of β-cells developing in embryoid bodies produced from such HESC. Cells expressing key β-cell markers were isolated by fluorescence-activated cell sorting after staining for high zinc content using the vital dye, Newport Green.\ud \ud \ud Conclusion\ud \ud Constitutive expression of Pax4 in HESC substantially enhances their propensity to form putative β-cells. Our findings provide a novel foundation to study the mechanism of pancreatic β-cells differentiation during early human development and to help evaluate strategies for the generation of purified β-cells for future clinical applications

Extensive field surveys in Lancashire and Merseyside have shown that for both Smerinthus ocellata (the eyed hawkmoth) and Laothoe populi (the poplar hawkmoth) there is a correlation between larval and foodplant coloration. For L. populi, experiments have shown that foodplant determines the colour of full grown caterpillars. Siblings reared on Salix fragilis L. (which has green leaves) became yellow-green, intermediate-green or dull-green whereas those reared on Populus alba L. became either white or green. Further experiments have shown that reflected light intensity may be the vital cue which determines whether a caterpillar becomes white or green. Thus for this species. the polymorphism is environmentally rather than genetically determined. However, the genetic background appears to have some effect on the proportion of dull-green and intermediate-green morphs in broods. For S. ocellata, both laboratory and field experiments have shown that the coloration of caterpillars is also determined by some environmental factors related to light. There is no simple genetic or nutritional control of larval colour in this species.\ud Pigment extraction and analysis have shown that the proportions of different carotenoids in the main foodplants are very similar, as are the chlorophyll a to b ratios and carotenoid to chlorophyll ratios. The principal carotenoid in the food of both species of caterpillar, lutein, is sequestered by the insects in the integument and contributes to the animal's coloration. Cis-lutein is also present in small quantities in the integuments of both L. populi and S. ocellata caterpillars. Yellow-green L. populi larvae contain more lutein in the integument than dull-green morphs and in white caterpillars this carotenoid is barely\ud detectable.\ud Field predation experiments indicated that white caterpillars of L. populi are at a selective advantage compared with yellow-green morphs on the white undersurface of P. alba leaves. However, both white and green morphs suffered similar predation on S. fragilis bushes.