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The purpose of this article is to shed light on the "darker" side of language in cross-cultural communication and explore ways that it can be addressed, using a dialogical approach. Bakhtin's dialogical perspective conceptualizes sensemaking as the co-construction of meaning through interconnected utterances ("addressivity" and "responsivity"), multivoicedness ("polyphony"), and multiple speaking styles ("heteroglossia"). We use these concepts to analyze the social processes underlying linguistic hegemony and language-based in-group behavior in a case study of the performance of six multicultural teams at an American subsidiary in France. We found that although dialogical practices proved to be effective in deterring the emergence of the dark side of language, the lack of a dialogical mindset prevailed in four of the six teams. These findings point to the need for cross-cultural management policies which reward addressivity, polyphony, and heteroglossia while penalizing team members who use their superior language skills to dominate others. [ABSTRACT FROM AUTHOR]

Polylactones are important biodegradable and biocompatible environmentally friendly polyesters widely used for many applications and more particularly for biomedical applications. This review covers recent advances dealing with their synthesis by ring-opening polymerization (ROP). First, lactones polymerized by ROP will be reviewed with special attention paid to the effect of the ring size on polymerizability. Aliphatic polyesters synthesized by the ROP of lactones can also be obtained by polycondensation. The advantages of ROP compared with polycondensation will be highlighted. The second section is devoted to the different mechanisms used to carry out ROP, such as anionic, coordination, cationic, enzymatic, and organocatalytic polymerization. Special attention will be paid to the control imparted to the polymerization by the use of catalysts and initiators. The polymerization of lactones substituted by functional groups will be shown to afford functionalized aliphatic polyesters. The final section will focus on the synthesis of different architectures such as star-shaped, graft, hyperbranched, and macrocyclic polylactones in the frame of macromolecular engineering. [ABSTRACT FROM AUTHOR]

Abstract: Advanced drug delivery systems rely on the availability of biocompatible materials. Moreover, biodegradability is highly desirable in the design of those systems. Consequently, aliphatic polyesters appear as a class of promising materials since they combine both properties. Nevertheless, their use in practical biomedical systems relies on clinical approval which not only depends on the material itself but also on its reproducible synthesis with the absence of residual toxics. The first sections of this review aim at reporting on the evolution of the initiators/catalytic systems and of the synthesis conditions (particularly the use of supercritical CO2 as polymerization medium) in order to produce aliphatic polyesters with controlled macromolecular parameters by still “greener” ways. In addition, the further development of delivery systems also depends on the synthesis of materials exhibiting novel properties, such as amphiphilicity or pH-sensitivity that are emerging from the active research in macromolecular engineering. Functionalizing aliphatic polyesters is quite tedious due to their sensitivity towards hydrolytic degradation. The last section of this review is discussing several strategies to obtain functional (co)polyesters of various architectures providing them with novel properties. [Copyright &y& Elsevier]

The infection of plants by obligate parasitic nematodes constitutes an interesting model for investigating plant cytoskeleton functions. Root knot nematodes have evolved the ability to manipulate host functions to their own advantage by redifferentiating root cells into multinucleate and hypertrophied feeding cells. These giant cells result from repeated rounds of karyokinesis without cell division. Detailed functional analyses demonstrated that Arabidopsis thaliana Microtubule-Associated Protein65-3 (MAP65-3) was essential for giant cell ontogenesis and that cytokinesis was initiated but not completed in giant cells. In developing giant cells, MAP65-3 was associated with a novel kind of cell plate--the giant cell mini cell plate--that separates daughter nuclei. In the absence of functional MAP65-3, giant cells developed but failed to fully differentiate and were eventually destroyed. These defects in giant cells impaired the maturation of nematode larvae. Thus, MAP65-3 is essential for giant cell development during root knot nematode infection. Subcellular localization of MAP65-3 and analysis of microtubule organization in the dyc283 T-DNA map65-3 mutant demonstrated that MAP65-3 played a critical role in organizing the mitotic microtubule array during both early and late mitosis in all plant organs. Here, we propose a model for the role of MAP65-3 in giant cell ontogenesis. [ABSTRACT FROM AUTHOR]

During a compatible interaction, root-knot nematodes ( Meloidogyne spp.) induce the redifferentiation of root cells into multinucleate nematode feeding cells (giant cells). Hyperplasia and hypertrophy of the surrounding cells leads to the formation of a root gall. We investigated the plant response to root-knot nematodes by carrying out a global analysis of gene expression during gall formation in Arabidopsis, using giant cell-enriched root tissues. Among 22 089 genes monitored with the complete Arabidopsis transcriptome microarray gene-specific tag, we identified 3373 genes that display significant differential expression between uninfected root tissues and galls at different developmental stages. Quantitative PCR analysis and the use of promoter GUS fusions confirmed the changes in mRNA levels observed in our microarray analysis. We showed that a comparable number of genes were found to be up- and downregulated, indicating that gene downregulation might be essential to allow proper gall formation. Moreover, many genes belonging to the same family are differently regulated in feeding cells. This genome-wide overview of gene expression during plant–nematode interaction provides new insights into nematode feeding-cell formation, and highlights that the suppression of plant defence is associated with nematode feeding-site development. [ABSTRACT FROM AUTHOR]

Sedentary plant-parasitic nematodes are able to induce the redifferentiation of root cells into multinucleate nematode feeding sites (NFSs). We have isolated by promoter trapping an Arabidopsis thaliana gene that is essential for the early steps of NFS formation induced by the root-knot nematode Meloidogyne incognita. Its pattern of expression is similar to that of key regulators of the cell cycle, but it is not observed with the cyst nematode. Later in NFS development, this gene is induced by both root-knot and cyst nematodes. It encodes a protein similar to the D-ribulose-5-phosphate 3-epimerase (RPE) (EC 5.1.3.1), a key enzyme in the reductive Calvin cycle and the oxidative pentose phosphate pathway (OPPP). Quantitative RT—PCR showed the accumulation of RPE transcripts in potato, as in Arabidopsis NFS. Homozygous rpe plants have a germination mutant phenotype that can be rescued in dwarf plants on sucrose-supplemented medium. During root development, this gene is expressed in the meristems and initiation sites of lateral roots. These results suggest that the genetic control of NFSs and the first stages of meristem formation share common steps and confirms the previous cytological observations which indicate that root cells undergo metabolic reprogramming when they turn into NFSs. [ABSTRACT FROM AUTHOR]

Abstract This paper explores an original approach in which greenhouse gas (GHG) emissions and carbon (C) accumulation are assessed monthly and at landscape scale to account for the highly seasonal monsoon climate and the mobility of pastoral herds that characterize West African pastoral ecosystems. The study was conducted in northern Senegal, in the service area of the Widou Thiengoly borehole, a circular zone of 706 km2 centered on the borehole. The C balance was calculated using an ecosystem approach, i.e. taking all main sources of GHG emissions and C sinks of the ecosystem, not only anthropogenic sources, into account. The annual C balance of the pastoral ecosystem was −0.04 ± 0.01 tC-eq.ha−1.year−1, showing that total GHG emissions were mitigated by C accumulation in trees, soil and livestock. The C balance varied considerably with the seasons, with a positive monthly balance in the wet season, from July to October (+0.58 tC-eq.ha−1.month−1) and a negative monthly balance in the cold dry season from November to February and the hot dry season from March to June (−0.57 and −0.05 tC-eq.ha−1.month−1 respectively). Care should be taken when generalizing these results, which were obtained in a dry year, because of strong inter-annual variations in rainfall. Highlights • Sahelian rangeland ecosystems have a neutral carbon balance. • Accumulation of carbon and greenhouse gas emissions vary strongly between seasons. • The main source of greenhouse gas emissions is livestock. • The main carbon sinks are trees and soils. • Seasonality is explained by both rainfall patterns and pastoral practices. [ABSTRACT FROM AUTHOR]

Ion Mobility (IM) coupled to Mass Spectrometry (MS) has been used for several decades, bringing a fast separation dimension to the MS detection. IM-MS is a convenient tool for structural elucidation. The folding of macromolecules is often assessed with the support of computational chemistry. However, this strategy is strongly dependent on computational initial guesses. Here, we propose the analysis of the Collision Cross-Section (CCS) trends of synthetic homopolymers based on a fitting method which does not rely on computational chemistry a prioris of the three-dimensional structures. The CCS trends were evaluated as a function of the polymer chain length and the charge state. This method is also applicable to mobility trends. It leads to two parameters containing all information available through IM(-MS) measurements. One parameter can be interpreted as an apparent density . The second parameter is related to the shape of the ions and leads us to introduce the concept of trends with constant apparent density . Based on the two fitting parameters, a method for IM trend predictions is elaborated. Experimental deviations from the predictions facilitate detecting structural rearrangements and three-dimensional structure differences of the cationized polymer ions. This leads for instance to an easy identification and prediction of the presence of different polymer topologies in complex polymer mixtures. The classification of predicted trends could as well allow for software-assisted data processing. Finally, we suggest the link between the CCS trends of homopolymers and those obtained from (monodisperse) biomolecules to interpret potential folding differences during IM-MS studies. [ABSTRACT FROM AUTHOR]

Abstract: Emergy accounting (EmA) was applied to a range of dairy systems, from low-input smallholder systems in South Mali (SM), to intermediate-input systems in two regions of France, Poitou-Charentes (PC) and Bretagne (BR), to high-input systems on Reunion Island (RI). These systems were studied at three different levels: whole-farm (dairy system and cropping system), dairy-system (dairy herd and forage land), and herd (animals only). Dairy farms in SM used the lowest total emergy at all levels and was the highest user of renewable resources. Despite the low quality of resources consumed (crop residues and natural pasture), efficiency of their use was similar to that of industrialised inputs by intensive systems in RI, PC and BR. In addition, among the systems studied, SM dairy farms lay closest to environmental sustainability, contradicting the usual image of high environmental impact of cattle production in developing countries. EmA also revealed characteristics of the three intensive systems. Systems from RI and PC had lower resource transformation efficiency and higher environmental impacts than those from BR, due mainly to feeding strategies that differed due to differing socio-climatic constraints. Application of EmA at multiple levels revealed the importance of a multi-level analysis. While the whole-farm level assesses the overall contribution of the system to its environment, the dairy-system level is suitable for comparison of multi-product systems. In contrast, the herd level focuses on herd management and bypasses debates about definition of system boundaries by excluding land management. Combining all levels highlights the contribution of livestock to the global agricultural system and identifies inefficiencies and influences of system components on the environment. [Copyright &y& Elsevier]

Abstract: This paper introduces a generic assessment method called pluri-energy analysis. It aims to assess the types of energy used in agricultural systems and their conversion efficiencies. Four types of energy are considered: fossil energy, gross energy contained in the biomass, energy from human and animal labor and solar energy. The method was applied to compare smallholder low-input dairy-production systems, which are common in developing countries, to the high-input systems encountered in OECD countries. The pluri-energy method is useful for analyzing the functioning of agricultural systems by highlighting their modes of energy management. Since most dairy systems in South Mali (SM) are low-input systems, they are primarily based on solar and labor energy types and do not require substantial fossil-energy inputs to produce milk. Farms in Poitou-Charentes (PC) and Bretagne (BR) show intermediate values of fossil-energy use for milk production, similar to that found in the literature for typical European systems. However, fossil-energy use for milk production is higher on PC than BR farms because of a higher proportion of maize silage in the forage area; grazing pastures are more common on BR farms. Farms on Reunion Island (RI) require a relatively large amount of fossil energy to produce milk, mainly because the island context limits the amount of arable land. Consequently, milk production is based on large imports of concentrated feed with a high fossil-energy cost. The method also enables assessment of fossil-energy-use efficiency in order to increase the performance of biological processes in agricultural systems. Comparing the low-input systems represented by SM to the high-input systems represented by RI, PC and BR, an increase in solar-energy conversion, and thus land productivity, was observed due to intensification via increased fossil-energy use. Conversely, though fossil-energy use at the herd level increased milk productivity, its effect on gross-energy conversion by the herd was less evident. Partitioning the total on-farm gross energy produced among animal co-products (milk, meat and manure) highlights the major functions of SM herds, which are managed to produce organic crop fertilizers. [Copyright &y& Elsevier]

Environmental impact assessment of agriculture has received increased attention over recent decades, leading to development of numerous methods. Among them, three deal with energy use: Energy Analysis (EA), Ecological Footprint (EF) and Emergy synthesis (Em). Based on a review of 197 references applying them to a variety of agricultural systems, this paper evaluates their ability to assess energy use. While EF assesses energy use as land use via a global accounting approach in which energy is only one component of the assessment, EA and Em are energy-focused and appear more appropriate to highlight ways to increase energy-use efficiency. EA presents a clear methodology via fossil energy use and its associated impacts but does not consider all energy sources. With inclusion of natural and renewable resources, Em focuses on other energy resources, such as solar radiation and energy from labour, but does not present impact indicators nor establish a clear link between activities and their environmental impacts. Improvements of the EA and Em methods could increase their ability to perform realistic and unbiased energy analysis or the diversity of livestock systems encountered in the world. First, to consider all energy sources, as Em does, EA could include solar radiation received by farm surfaces and energy expenditure by humans and animals to accomplish farm operations. Second, boundaries of the studied system in EA and Em must include draft animals, humans and communal grazing lands. Third, special attention should be given to update and locally adapt energy coefficients and transformities. [Copyright &y& Elsevier]

Background: In eukaryotes, the spindle assembly checkpoint (SAC) ensures that chromosomes undergoing mitosis do not segregate until they are properly attached to the microtubules of the spindle. Methodology/Principal Findings: We investigated the mechanism underlying this surveillance mechanism in plants, by characterising the orthogolous SAC proteins BUBR1, BUB3 and MAD2 from Arabidopsis. We showed that the cell cycle-regulated BUBR1, BUB3.1 and MAD2 proteins interacted physically with each other. Furthermore, BUBR1 and MAD2 interacted specifically at chromocenters. Following SAC activation by global defects in spindle assembly, these three interacting partners localised to unattached kinetochores. In addition, in cases of 'wait anaphase', plant SAC proteins were associated with both kinetochores and kinetochore microtubules. Unexpectedly, BUB3.1 was also found in the phragmoplast midline during the final step of cell division in plants. Conclusions/Significance: We conclude that plant BUBR1, BUB3.1 and MAD2 proteins may have the SAC protein functions conserved from yeast to humans. The association of BUB3.1 with both unattached kinetochore and phragmoplast suggests that in plant, BUB3.1 may have other roles beyond the spindle assembly checkpoint itself. Finally, this study of the SAC dynamics pinpoints uncharacterised roles of this surveillance mechanism in plant cell division. [ABSTRACT FROM AUTHOR]

Abstract: GAMEDE is a stock-flow dynamic simulation model designed with farmers to represent dairy farm functioning and the consequences of the farmer’s daily management decisions for whole-farm sustainability. Sustainability is evaluated according to its three pillars: technico-economic viability, respect for environment, and social liveability. The model provides original information for a better understanding of the processes regulating nitrogen dynamics within the farm, and the factors determining farmers’ decisions and practices. Model implementation experiments have revealed that GAMEDE is also a useful tool to support discussions and to generate knowledge exchange among various stakeholders who play an important role in the development of farm sustainability: farmers, extension agents and researchers. While a majority of researchers and advisers are specialised and a majority of farmers fix their attention on specific and narrow themes of farm management, such a comprehensive model can help stakeholders complement their knowledge to gain a holistic view of the farming system. This holistic and integrated view is crucial: (i) for researchers who wish to explain diversity in farming systems and understand decisional and biophysical processes and their interrelated effects operating in such complex agro-ecosystems, (ii) for advisers whose aim is to define alternative management strategies applicable in practice, i.e. taking into account farm specificities, and (iii) for farmers who must choose practices compatible with their resources, assets, constraints and objectives. Holism can also improve versatility and thus the generic character of models. Issues are narrowly specified and greatly vary both among categories of stakeholders (e.g. scientists versus farmers) and within each category (e.g. among farmers). A comprehensive model that: (i) details all farm management operations, and (ii) represents their effects on different spatio-temporal levels and on the three sustainability dimensions, is more likely to respond to the various issues facing different stakeholders. We argue that capacity of models to respond to stakeholders’ questions has to be considered in future evaluations of decision support systems. [Copyright &y& Elsevier]

Abstract: Synthesis of an asymmetric tadpole-shaped aliphatic copolyester consisting of a poly(ɛ-caprolactone) ring and two poly(l-lactide) tails was reported for the first time. First, a high molecular weight cyclic PCL macroinitiator (M n =31,000) was prepared by intramolecular photocross-linking of “living” chains. Polymerization of l-lactide was resumed by the tin dialkoxide containing macrocycles, thus making the targeted tadpole-shaped copolyester available. A preliminary investigation of the crystallization of these copolyesters was carried out by differential scanning calorimetry and polarized optical microscopy. [Copyright &y& Elsevier]

Arabidopsis thaliana transgenic plants expressing the mannose binding lectin GNA from snowdrop (Galanthus nivalis), under the control of the constitutive 35S promoter of the Cauliflower Mosaic Virus (CaMV) with an enhancer sequence were produced. They were used to investigate the potential of this lectin to control the root-knot nematode Meloidogyne incognita. Homozygous lines expressing GNA in roots at an estimated range of 0.1–1.3% of total soluble proteins were selected. Protection against root-knot nematodes was investigated in an in vitro test. Some lines had a significant decrease (20–50%) in root gall number. However, one line showed a higher gall number compared to the control line. This effect, which is not correlated to GNA protein root level, suggests a complex action mechanism of lectin against nematodes. Nevertheless, GNA seems to have a strong potential against M. incognita and could be used as a component of integrated pest management programs. [Copyright &y& Elsevier]

Agricultural intensification to ensure food security and limit rural exodus is a major issue in sub-Saharan Africa. The potential of livestock farming to improve the sustainability of farming systems has been studied but rarely at the landscape level. However, because the herds move about in the landscape, thereby creating horizontal biomass and nutrient flows between plots and households, the landscape is the only level where all the interactions between the different components of the agro-ecosystem (animals, crops and trees) can be considered. Our objective was to develop a methodology that uses territorial metabolism for multicriteria assessment of sustainability to compare contrasted livestock systems. We compare two neighboring village terroirs in the former groundnut basin of Senegal. One village (Diohine), has kept a "traditional extensive system" based on fallow, free grazing and night corralling, while the other (Barry) uses a "modern semi-intensive system" based on livestock fattening in which the livestock is stall-fed with feed concentrate and crop residues. During the survey, village households were asked to describe their practices and to quantify biomass and nitrogen (N) flows to enable us to calculate sustainability indicators (productivity, balance, efficiency, dependency, profitability) at plot, household and village terroir levels. At village terroir level, introducing livestock fattening increased the livestock stocking rate (0.96 TLU ha-1 in Diohine and 2.31 TLU ha-1 in Barry) and spreading of solid manure on crop fields (respectively 337 and 482 kgDM ha-1). Fattening livestock requires large imports of feed concentrate, 23.67 kgN ha-1 in Barry versus 3.39 kgN ha-1 in Diohine. The improved livestock productivity of fattening (+217 kgLW ha-1) produces higher financial returns (+432€ household-1 year-1) that enable the use of more mineral fertilizers (6.28 kgN ha-1 in Barry versus 1.09 kgN ha-1 in Diohine). The additional N inputs in Barry enable increased yields of the main staple crop (millet) (+101 kgDM ha-1). The population density of Barry village is +78% higher (320 capita km-2 in Barry versus 180 capita km-2 in Diohine). The village nitrogen balance (24.88 kgN ha-1 in Barry versus 8.51 kgN ha-1 in Diohine) and N use efficiencies (respectively 0.64 and 0.15) demonstrate that nutrient cycling and soil fertility management are more sustainable in Barry. We propose a methodology to rebuild territorial metabolism from surveys. Territorial metabolism is used to calculate a set of multi-criteria sustainability indicators. This methodology will be particularly useful in sub-Saharan Africa where data on agricultural systems are lacking. [Display omitted] • Two neighboring villages with contrasted crop-livestock systems are compared • Livestock is shown to be a sustainable intensification pathway • Sustainability indicators have different values depending on the level of analysis • Multi-level analysis can identify bottlenecks in nutrient cycles in crop-livestock systems. [ABSTRACT FROM AUTHOR]

Although old molecules, alkylating agents and platinum derivatives are still widely used in the treatment of various solid tumors. However, systemic toxicity and cellular resistance mechanisms impede their efficacy. Innovative strategies, including local administration, optimization of treatment schedule/dosage, synergistic combinations, and the encapsulation of bioactive molecules in smart, multifunctional drug delivery systems, have shown promising results in potentiating anticancer activity while circumventing such hurdles. Furthermore, questioning of the old paradigm according to which nuclear DNA is the critical target of their anticancer activity has shed light on subcellular alternative and neglected targets that obviously participate in the mediation of cytotoxicity or resistance. Thus, rethinking of the use of these pivotal antineoplastic agents appears critical to improve clinical outcomes in the management of solid tumors. Highlights Alkylating agents and platinum derivatives remain key in the management of solid tumors. Conventional clinical practice is dramatically impeded by cellular and molecular resistance mechanisms to alkylating agents and platinum derivatives. The design of alternative strategies that aim at rethinking the use of these old drugs is of paramount importance to give them a new impetus in oncology. Synergistic combinations and optimization of the treatment schedule/dosage by metronomic chemotherapy have shown positive outcomes in cancer patients. Local drug delivery and targeting of critical organelles in cancer cells through the investigation of new routes of administration and the encapsulation of bioactive molecules inside smart, multifunctional drug delivery systems constitute promising strategies to potentiate the therapeutic index of alkylating agents and platinum derivatives while circumventing drug resistance. [ABSTRACT FROM AUTHOR]

Polymer characterizations are often performed using mass spectrometry (MS). Aside from MS and different tandem MS (MS/MS) techniques, ion mobility–mass spectrometry (IM-MS) has been recently added to the inventory of characterization technique. However, only few studies have focused on the reproducibility and robustness of polymer IM-MS analyses. Here, we perform collisional and electron-mediated activation of polymer ions before measuring IM drift times, collision cross-sections (CCS), or reduced ion mobilities (K0). The resulting IM behavior of different activated product ions is then compared to non-activated native intact polymer ions. First, we analyzed collision induced unfolding (CIU) of precursor ions to test the robustness of polymer ion shapes. Then, we focused on fragmentation product ions to test for shape retentions from the precursor ions: cation ejection species (CES) and product ions with m/z and charge state values identical to native intact polymer ions. The CES species are formed using both collision induced dissociation (CID) and electron transfer dissociation (ETD, formally ETnoD) experiments. Only small drift time, CCS, or K0 deviations between the activated/formed ions are observed compared to the native intact polymer ions. The polymer ion shapes seem to depend solely on their mass and charge state. The experiments were performed on three synthetic homopolymers: poly(ethoxy phosphate) (PEtP), poly(2-n-propyl-2-oxazoline) (Pn-PrOx), and poly(ethylene oxide) (PEO). These results confirm the robustness of polymer ion CCSs for IM calibration, especially singly charged polymer ions. The results are also discussed in the context of polymer analyses, CCS predictions, and probing ion–drift gas interaction potentials. Graphical Abstract [ABSTRACT FROM AUTHOR]

Domestic species such as cattle (Bos taurus taurus and B. t. indicus) represent attractive biological models to characterize the genetic basis of short‐term evolutionary response to climate pressure induced by their post‐domestication history. Here, using newly generated dense SNP genotyping data, we assessed the structuring of genetic diversity of 21 autochtonous cattle breeds from the whole Mediterranean basin and performed genome‐wide association analyses with covariables discriminating the different Mediterranean climate subtypes. This provided insights into both the demographic and adaptive histories of Mediterranean cattle. In particular, a detailed functional annotation of genes surrounding variants associated with climate variations highlighted several biological functions involved in Mediterranean climate adaptation such as thermotolerance, UV protection, pathogen resistance or metabolism with strong candidate genes identified (e.g., NDUFB3, FBN1, METTL3, LEF1, ANTXR2 and TCF7). Accordingly, our results suggest that main selective pressures affecting cattle in Mediterranean area may have been related to variation in heat and UV exposure, in food resources availability and in exposure to pathogens, such as anthrax bacteria (Bacillus anthracis). Furthermore, the observed contribution of the three main bovine ancestries (indicine, European and African taurine) in these different populations suggested that adaptation to local climate conditions may have either relied on standing genomic variation of taurine origin, or adaptive introgression from indicine origin, depending on the local breed origins. Taken together, our results highlight the genetic uniqueness of local Mediterranean cattle breeds and strongly support conservation of these populations. [ABSTRACT FROM AUTHOR]

Highlights • Flock mobility impacts on CH 4 can be modelled by taking into account feed diversity. • Flock mobility increased net CH 4 emissions of sheep farming systems. • Pastoral systems produced the highest lambs’ CH 4 emission per unit of product. • Ewes in sedentary systems produced the highest CH 4 emissions (kg/year). Abstract Ruminant livestock systems are significant sources of greenhouse gases (GHG). Livestock farming in regions with extreme climatic events have to face both scarcity and variability in feed resources. Herd mobility is a known major adaptation strategy to address seasonal availability of forage resources: it allows an increase in herd size, thereby improving labor productivity. The present study quantifies enteric methane (CH 4) emissions from French Mediterranean sheep farming systems, focusing on the use of diversified pastoral feed resources, and developing a calculator (Diversity of feed REsources and Enteric Methane emissions, DREEM). The DREEM calculator was developed to estimate at the animal level enteric CH 4 emissions (g/day) from empirical equations and be subsequently integrated, as a sub-table, into an economic and GHG (kg/year) balance model (Outil de Simulation du TRoupeau ovin ALaitant, OSTRAL) at the whole farm level. Several equations were taken from the literature to estimate enteric CH 4 emissions in DREEM calculator. Nature of forage and feed, animal feeding levels and performance were referenced according to the animal feeding system and tables in France and taking into account the French Mediterranean area studied. DREEM was used to estimate enteric CH 4 emissions from four sheep farming systems covering the main contrasting mobility and situations, from sedentary to highly mobile pastoral systems, in the French Mediterranean area. At the individual level, enteric CH 4 emissions (g/day) of ewes in the sedentary system were slightly higher than those of ewes in other systems. These differences were due mainly to differences in animal feeding level (intake / body weight) and feed resources characteristics. Overall, enteric CH 4 emissions of ewes and rams were slightly lower than French national inventory estimates. When enteric CH 4 emissions of lambs were expressed in g/kg of carcass, were lower in the less pastoral farming systems than in the other systems, because lambs’ average daily gains were higher. In double transhuming farming systems, lambs late slaughtering age led to lamb’s CH 4 contribution of 15% vs 2–5% in the other systems. Flock management, which depends on land use and ownership, greatly contributed to these results. [ABSTRACT FROM AUTHOR]

Pastoral farming systems have always adapted to the seasonal availability of forage resources and climate variability by moving animals. However, the role of animal mobility as a possible mitigating strategy in response to climate change has not been clearly documented. To understand this role, we investigated (i) the major methodological challenges linked to the diversity of grazing areas and other forage resources exploited by these systems and enteric emissions of methane; (ii) the impacts of grazing practices (carbon sequestration/emission) on soil and biomass carbon fluxes. We developed an approach based on two existing models (OSTRAL: Outil de Simulation du TRoupeau ovin ALlaitant and CASA: Carnegie Ames Stanford Approach) that we adapted and used in combination. This approach was applied to three French Mediterranean sheep and crop farming systems with different degrees of flock mobility (sedentary, single transhumance and double transhumance). The preliminary results produced by the whole farm model OSTRAL showed that two systems (sedentary and double transhumance) causing low carbon emissions. In the sedentary system, higher animal productivity offsets the increase in GHG emissions (in CO 2 eq) caused by feed production. In the pastoral system, grazing reduced total GHG emissions (in CO 2 eq). The CASA model proved to be useful to simulate the carbon balance under dynamic land cover in natural environments, whether used for grazing or not. This model can help assess the impact of grazing practices and carbon fluxes in systems linked to natural environments. The results of the first application showed that seasonal mobility of livestock increases the contribution of rangeland to feeding systems and improves the non-renewable energy balance of the system. It is thus extremely important to include the specificities of animals grazing in rangelands outside the structural limits of the farm when evaluating GHG emissions. [ABSTRACT FROM AUTHOR]

The copolymerization of ε-caprolactam with ethyl 4-(butylamino)benzoate was shown to occur in the presence of sodium salts and an acyllactam as activator in a one-step bulk reaction. The mechanism is based on the deprotonation of the two monomers yielding activated species able to attack an acyllactam or an ester group at the polymer chain ends. Novel copolyamides with different percentages of aromatic/aliphatic units were synthesized in a one-step bulk copolymerization within a few minutes at 140 °C and characterized by NMR spectroscopy, size exclusion chromatography, and thermal analysis (DSC). This methodology, combining simultaneous anionic ring-opening and condensation reactions, affords a new synthetic pathway to introduce an aromatic unit in an aliphatic polyamide backbone, and more specifically a polyamide 6 containing about 20 mol % of N-alkyl aromatic amides was prepared. [ABSTRACT FROM AUTHOR]

The polymerization of cyclic phosphates to poly(phosphoester)s, PPEs, is optimized for chip-based microreactors under continuous flow conditions. The anionic ring-opening polymerization of 2-isobutyoxy-2-oxo-1,3,2-dioxaphospholane (iBP) via the use of two organocatalytic systems allowed to polymerize to nearly quantitative monomer conversion within 10 or 3 min, respectively at a reaction temperature of 40 °C. Further, the optimized polymerization protocol was applied to 2-butenoxy-2-oxo-1,3,2-dioxaphospholane (BP) which yields a polymer that carries an alkene functionality per monomer repeating unit. This material can be postmodified in an UV-induced radical thiol–ene reaction, which was also shown to proceed with very high efficiency under UV-flow conditions. Eventually, both reactions were coupled in a two-stage reactor setup, showing that the thermally-activated polymerization can be coupled with high efficiency to the UV-activated post-polymerization modification reaction. The introduced reactor setup can in the future be used to produce and screen a broad variety of functional PPE materials with various functionalities and physical properties. [ABSTRACT FROM AUTHOR]

Since the discovery in the early 1950s of fixation of industrial atmospheric nitrogen through physico-chemical processes, mineral fertilisation has become the main means of fertilising cultivated land. However, several studies have shown that continued use of mineral fertilisers can accelerate soil acidification and reduce cation exchange capacity, water-holding capacity, and soil microbial activity, thereby reducing soil fertility. Other studies have underlined the importance of a nutrient balanced fertilisation protocol to sustain high grass yields. On the other hand, by recycling livestock manure, the use of organic fertiliser has been shown to lead to high soil productivity and to provide economic and environmental benefits to farmers. Our study focused on the short- and long-term effects of several types of fertilisers, (mineral, organic, and mixed organic-mineral), and several doses (ranging from 440 to 1,260kgN/ha/year) in a 15-year experiment on highly productive grassland. We showed that, in contrast to organic fertilisation, although the mineral treatments maintained soil nitrogen content, these treatments did not increase phosphorous and potassium concentrations, and in addition, led to soil acidification. Furthermore, although mineral fertilisation led to rapid increases in grass yield, its fertilisation effect weakened over time whereas some of the organic fertilisation treatments resulted in a gradual increase in grass yields. Significant differences in grassland productivity were observed between the effects of liquid manure and compost, liquid manure being more immediately effective while compost had a longer-term positive effect on grass yield. The mixed organic-mineral treatments were shown to be a good compromise, with a significant short-term increase in grass yields plus sustained grass production over time. • Mineral and manure fertilisation produce the most rapid increase in grass yields. • Total nitrogen input is the main factor in predicting grass yields. • Mineral fertilisation reduces soil nutrients and organic fertilisation increases them. • Long-term organic fertilisation, especially compost, increases grass yields. • Mixed fertilisation leads to both short- and long-term increases in grass yields. [ABSTRACT FROM AUTHOR]

• Organic and mineral fertilization increased both grass productivity and soil C stocks. • Carbon storage is still increasing after 15 years of intense fertilization. • Fertilization indirectly increases soil C stocks through increased plant productivity. • The main source of C stocks was direct inputs of organic C. • A large proportion of increased C stocks was observed in the deep soil layers. Previous long-term experiments conducted more than 10 years ago, showed that long-term application of organic fertilizer increased soil organic carbon (SOC) of grasslands. However, it was usually assumed that, independent of the successive additions of fertilizer, soils have an upper limit to their SOC due to the inability of the soil mineral phase to fix additional carbon. Andosols of the volcanic Reunion Island are typically very rich in carbon and are usually considered as saturated in SOC. To assess the long-term effect of different types of fertilization on SOC in these soils, SOC concentrations were recorded at yearly intervals for 15 years in one arenosol site and in two andosols sites across a topo-sequence. The types of fertilization tested included inorganic, organic, and a mix of inorganic and organic nutrient sources. The addition of organic fertilizers increased soil carbon in the top (0–15 cm) horizon in both the arenosol and the two andosols (up to +250% in the arenosol and up to +41% in the andosol), whereas inorganic fertilizers and the control treatment did not always result in a significant increase in SOC. After 15 years, no plateau was reached in C stocks even with the highest fertilization rates. Our results suggest that SOC build-up was mainly due to inputs of organic fertilizer C, rather than to increased C inputs due to the fertilizer-induced increased crop yield. In the andosol, all the fertilization treatments led to higher concentrations of carbon in the deeper layers. This suggests that SOC inputs lead to downward migration of OC to deep horizons. For C-rich soils like andosols, assessing the variations in carbon in the deep horizon is thus critical in estimating the effects of soil management on carbon sequestration. [ABSTRACT FROM AUTHOR]

ABSTRACT The allyl phosphoester group is shown to be a protecting group for the synthesis of anionic polyphosphodiesters. Our strategy relies on the synthesis of a cyclic phosphate monomer bearing a pendant allyl phosphoester group, its easy purification by fractional distillation, its organocatalyzed ring-opening polymerization by 1,8-diazobicyclo[5.4.0]undec-7-ene (DBU) and 1-[3,5- bis(trifluoromethyl)phenyl]-3-cyclohexyl-thiourea (TU). Finally, the deprotection of the allyl phosphoester group is carried out by reaction with sodium benzenethiolate in the absence of any detectable degradation. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2642-2648 [ABSTRACT FROM AUTHOR]

Aliphatic polyamide (PA) bearing fluorinated groups was synthesized in bulk with perfluorobutyryl-substituted α-amino-ε-caprolactam and ε-caprolactam by anionic ring-opening polymerization (AROP). The fluorinated monomer was obtained by condensation between cyclic lysine ( i.e. α-amino-ε-caprolactam) and perfluorobutyryl chloride. The effect of the fluorinated monomer fraction onto the AROP of ε-caprolactam was monitored by the exothermicity of this polymerization versus time. The properties and characteristics of the resulting polymers were studied by with differential scanning calorimetry, thermogravimetry, magic angle spinning NMR, FT-IR, and contact angle measurements. Polyamides bearing fluorinated groups exhibited better thermal stability than polyamide 6 (PA6) as well as a higher hydrophobic surface character as evidenced by surface tension measurements. The glass transition temperature of polyamide 6 was 53 °C and rose to 58 °C for a PA bearing fluorinated moieties, while fluorinated monomer insertion induced a decrease of the melting points from 216 to 198 °C. These copolymers displayed a maximum degradation temperature of 390 °C as compared to the 310 °C for PA6, and their surface energies decreased from 49.4 mN cm −1 (PA6 value) to 44.1 mN cm −1 . [ABSTRACT FROM AUTHOR]

Growing awareness of the multiple environmental impacts of livestock production has created a need to extend the definition of efficiency to a multidimensional eco-efficiency concept. Our paper proposes an original methodology, named “simulation based DEA” that combines an agronomic whole-farm model and an efficient frontier method for in-depth exploration of the determinants of eco-efficiency. GAMEDE, the whole-farm model we use, is randomly parameterized for key management practices and structural parameters to generate a large dataset of simulated dairy systems. The upper and lower bounds set for the stochastic choice of parameter values are a key point in the methodology and rely on expert knowledge derived from participatory modelling. For each simulation, numerous indicators describing the functioning and the performance of the production system are calculated and a set of inputs, outputs, and undesirable outputs, are then used to define the production technology in an efficiency frontier analysis. Data envelopment analysis, the efficiency frontier method applied, provides a multidimensional eco-efficiency score representing the increase in outputs that is possible with no increase in inputs or undesirable outputs. The eco-efficiency score can be linked to all the indicators of the production system calculated by the whole-farm model, after which it becomes possible to explore the managerial, structural, economic, agronomic, zootechnical, and environmental factors that explain different levels of eco-efficiency. In our case study, dairy farming in Reunion Island, livestock production is strongly constrained by land scarcity. Consequently the most eco-efficient farms appear to be intensive systems with high forage productivity to ensure feed self-sufficiency. While most studies on efficiency are restricted to a narrow dataset, the proposed methodology is innovative in that it makes it possible to cover a wide range of possible livestock farming systems in a given territory, including systems that do not exist at the present time, and to characterize them using multiple descriptive variables, at a limited cost in time and in the cost of surveys. Coupling whole-farm models and efficiency frontier analysis is a promising way to accurately identify the determinants of eco-efficiency and ecological intensification pathways. [ABSTRACT FROM AUTHOR]

In previous works, poly(D,L-lactide-co-εCL-poly(ethylene glycol) (poly(D,L-La-co-αPEGεCL) amphiphilic graftcopolymers were successfully synthesized according to a copper azide-alkyne cycloaddition (CuAAC) strategy. This paper aims at reporting on the behavior of this amphiphilic copolymer in water, which was not studied in the previous paper. Moreover, the ability of the copolymer to stabilize a PLA nanoparticles aqueous suspension is presented. For this purpose, dynamic light scattering (DLS) and transmission electron microscopy (TEM) are proposed to characterize the nanoparticles in solution. Otherwise, the strategy developed for the synthesis of the amphiphilic copolymers was adapted and extended to the synthesis of PLA-based degradable hydrogel, potentially applicable as drug-loaded degradable polymer implant. [ABSTRACT FROM AUTHOR]

The spindle assembly checkpoint ( SAC) is a refined surveillance mechanism which ensures that chromosomes undergoing mitosis do not segregate until they are properly attached to the spindle microtubules ( MT). The SAC has been extensively studied in metazoans and yeast, but little is known about its role in plants., We identified proteins interacting with a MT-associated protein MAP65-3, which plays a critical role in organising mitotic MT arrays, and carried out a functional analysis of previously and newly identified SAC components., We show that Arabidopsis SAC proteins BUB3.1, MAD2, BUBR1/ MAD3s and BRK1 interact with each other and with MAP65-3. We found that two BUBR1/ MAD3s interacted specifically at centromeres. When stably expressed in Arabidopsis, BRK1 localised to the kinetochores during all stages of the mitotic cell cycle. Early in mitosis, BUB3.1 and BUBR1/ MAD3.1 localise to the mitotic spindle, where MAP65-3 organises spindle MTs. A double-knockout mad3.1 mad3.2 mutant presented spindle MT abnormalities, chromosome misalignments on the metaphase plate and the production of lagging chromosomes and micronuclei during mitosis., We conclude that BRK1 and BUBR1/ MAD3-related proteins play a key role in ensuring faithful chromosome segregation during mitosis and that their interaction with MAP65-3 may be important for the regulation of MT-chromosome attachment. [ABSTRACT FROM AUTHOR]

Photosensitive polymers have gainedstrong attention in developmentof different polymeric systems for diverse applications. Particularattention is paid to polymers with cinnamoyl groups either in polymerbackbone or in pendent position owing to their excellent photoreactivityand thermoreactivity upon UV light irradiation or heating. This workaims at synthesizing a novel photo- and thermosensitive aliphaticpolyamide by anionic ring-opening copolymerization of ε-caprolactamand α-cinnamoylamido-ε-caprolactam. The photochemicalreversible cross-linking of solutions and thermal cross-linking ofspin-coated films made up of these new cinnamoyl-functionalized polyamideswere monitored by UV–vis spectroscopy. These aliphatic polyamidecopolymers were characterized by magic angle spinning solid-stateNMR, and their thermal behaviors were studied by thermogravimetricanalysis, differential scanning calorimetry, and dynamic mechanicalanalysis. [ABSTRACT FROM AUTHOR]

Abstract: Due to the large number of applications of bisphenol-A (BPA), the human exposure routes are multiple. We aimed to review shortly the food and non-food sources of BPA, and to evaluate their contribution to the human exposure. Food sources discussed here include epoxy resins, polycarbonate and other applications, such as paperboard and polyvinylchloride materials. Among the non-food sources, exposures through dust, thermal paper, dental materials, and medical devices were summarized. Based on the available data for these exposure sources, it was concluded that the exposure to BPA from non-food sources is generally lower than that from exposure from food by at least one order of magnitude for most studied subgroups. The use of urinary concentrations from biomonitoring studies was evaluated and the back-calculation of BPA intake seems reliable for the overall exposure assessment. In general, the total exposure to BPA is several orders of magnitude lower than the current tolerable daily intake of 50μg/kgbw/day. Finally, the paper concludes with some critical remarks and recommendations on future human exposure studies to BPA. [Copyright &y& Elsevier]

Summary [ABSTRACT FROM AUTHOR]

Root-knot nematodes (RKN) are obligatory plant parasitic worms that establish and maintain an intimate relationship with their host plants. During a compatible interaction, RKN induce the redifferentiation of root cells into multinucleate and hypertrophied giant cells essential for nematode growth and reproduction. These metabolically active feeding cells constitute the exclusive source of nutrients for the nematode. Detailed analysis of glutathione (GSH) and homoglutathione (hGSH) metabolism demonstrated the importance of these compounds for the success of nematode infection in Medicago truncatula. We reported quantification of GSH and hGSH and gene expression analysis showing that (h)GSH metabolism in neoformed gall organs differs from that in uninfected roots. Depletion of (h)GSH content impaired nematode egg mass formation and modified the sex ratio. In addition, gene expression and metabolomic analyses showed a substantial modification of starch and γ-aminobutyrate metabolism and of malate and glucose content in (h)GSH-depleted galls. Interestingly, these modifications did not occur in (h)GSH-depleted roots. These various results suggest that (h)GSH have a key role in the regulation of giant cell metabolism. The discovery of these specific plant regulatory elements could lead to the development of new pest management strategies against nematodes. [ABSTRACT FROM AUTHOR]

Background: Carotenoids are isoprenoid pigments, essential for photosynthesis and photoprotection in plants. The enzyme phytoene synthase (PSY) plays an essential role in mediating condensation of two geranylgeranyl diphosphate molecules, the first committed step in carotenogenesis. PSY are nuclear enzymes encoded by a small gene family consisting of three paralogous genes (PSY1-3) that have been widely characterized in rice, maize and sorghum. Results: In wheat, for which yellow pigment content is extremely important for flour colour, only PSY1 has been extensively studied because of its association with QTLs reported for yellow pigment whereas PSY2 has been partially characterized. Here, we report the isolation of bread wheat PSY3 genes from a Renan BAC library using Brachypodium as a model genome for the Triticeae to develop Conserved Orthologous Set markers prior to gene cloning and sequencing. Wheat PSY3 homoeologous genes were sequenced and annotated, unravelling their novel structure associated with intron-loss events and consequent exonic fusions. A wheat PSY3 promoter region was also investigated for the presence of cis-acting elements involved in the response to abscisic acid (ABA), since carotenoids also play an important role as precursors of signalling molecules devoted to plant development and biotic/abiotic stress responses. Expression of wheat PSYs in leaves and roots was investigated during ABA treatment to confirm the up-regulation of PSY3 during abiotic stress. Conclusions: We investigated the structural and functional determinisms of PSY genes in wheat. More generally, among eudicots and monocots, the PSY gene family was found to be associated with differences in gene copy numbers, allowing us to propose an evolutionary model for the entire PSY gene family in Grasses. [ABSTRACT FROM AUTHOR]

This article reports on the synthesis of a new pH-sensitive amphiphilic A2B mikto-arm star-shaped aliphatic copolyester [with A = poly(ε-caprolactone) and B = tertiary amine-bearing poly(ε-caprolactone)] with two hydrophobic arms and one hydrophilic arm when protonated at pH = 5.5. First, the ring-opening polymerization of ε-caprolactone (εCL) was initiated by an aliphatic diol substituted by an alkyne. The copper(I) catalyzed azide-alkyne cycloaddition (CuAAC) was use to convert the alkyne into a hydroxyl group prone to initiate the ring-opening copolymerization of γ-bromo-ε-caprolactone (γBrεCL) and εCL. After the substitution of the bromide atoms into azide functions, the N,N-dimethylprop-2-yn-1-amine was grafted onto the azide bearing PCL arm by CuAAC, with the purpose to make the B arm hydrophilic at low pH. The precursors of the A2B copolymers were characterized by 1H NMR, SEC, and MALDI-TOF. As expected, the A2B copolyester was soluble into water at pH = 5. The formation of polymersomes in water at pH 5 was assessed by DLS and TEM analyses. The effects of the architecture and the molecular weight of the A2B copolymers on the formation of polymersomes were investigated. Moreover, the versatility of our approach was demonstrated by the synthesis of an AB2 star-shaped copolyester. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

Abstract: On the tropical island of La Réunion, population growth, increasing demand in food products, agricultural densification, and the resulting pressure on the environment are representative of what is expected to happen in the majority of the world’s regions in the next decades. Crop-livestock integration is a possible solution for the sustainable intensification of farming systems. GAMEDE, a whole-farm model, was designed and used with six representative dairy farmers on the island to ex-ante assess differences in farm sustainability of various degrees of crop-livestock integration and to support discussions with farmers about these options. The model details the dynamics of the main biophysical and decisional processes affecting labour, gross margin, and energy and nutrient flows within the farm. We propose a method based on typology, modelling and participatory techniques to support policy making. All its methodological stages integrate both quantitative and qualitative data. The large majority of farm model implementation cases reported in the literature refers to constructed synthetic farms. However, in our case, actual farm simulation was particularly useful for capturing farmers’ expert knowledge and providing insights into how agro-ecosystems are really managed. This approach enabled taking farm diversity into account in defining relevant interventions. The reliability of extrapolations and recommendations for policy formulation based on farm-level simulation were verified by a rigorous evaluation of the representativeness of the farm sample, crossing expert data with data stemming from a multi-variate analysis. Our research indicates that actual farms can also be typical. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the synthesis of a novel amphiphilic AB2 triarm star-shaped copolymer with A=non-toxic and biocompatible hydrophilic poly(ethylene oxide) (PEO) and B=biodegradable and hydrophobic poly(ε-caprolactone) (PCL). A series of AB2 triarm star-shaped copolymers with different molecular-weights for the PCL block were successfully synthesized by a three-step procedure. α-Methoxy-ω-epoxy-poly(ethylene oxide) (PEO-epoxide) was first synthesized by the nucleophilic substitution of α-methoxy-ω-hydroxy-poly(ethylene oxide) (MPEO) on epichlorohydrin. In a second step, the α-methoxy-ω,ω′-dihydroxy-poly(ethylene oxide) (PEO(OH)2) macroinitiator was prepared by the selective hydrolysis of the ω-epoxy end-group of the PEO-epoxide chain. Finally, PEO(OH)2 was used as a macroinitiator for the ring-opening polymerization (ROP) of ε-caprolactone (εCL) catalyzed by tin octoaote (Sn(Oct)2). PEO-epoxide, PEO(OH)2 and the AB2 triarm star-shaped copolymers were assessed by 1H NMR spectroscopy, size exclusion chromatography (SEC) and MALDI-TOF. The behavior of the AB2 triarm star-shaped copolymer in aqueous solution was studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). [Copyright &y& Elsevier]

Abstract: Crop-livestock farms are complex systems. The interactions operating in such systems involve decisional, biophysical, structural, and environmental factors. Moreover, as farmers face a large range of management options, tools are needed to support their decision-making to enable them to reach production levels meeting their objectives and compatible with their human and physical resources, while controlling their effects on the environment. Gamede, a whole-dairy-farm model, has been developed to explore this complexity and to represent dynamically the effect of management decisions on biomass and nitrogen flows and on numerous sustainability indicators, such as milk and forage crop productivity, labour requirements, nitrogen balance, and nitrogen efficiency. This article describes the integration of six modules accounting for biophysical processes in a dairy farm (forage production; forage conditioning; herd demography; milk, excreta and animal biomass productions; grazing, quality of fertilisers; and nitrogen gaseous emissions) together with a decision system accounting for the farmer’s strategy and technical operations. Most of the six biophysical modules incorporate mathematical models from the literature, but the decision system stems from our own original work. Six commercial farms with different structures, agro-climatic conditions and management strategies were used for validation. The model can explain the differences found in their sustainability indicators at the year scale. The intra-year variability of the main biomass stocks and flows is also well explained. This quantitative validation was completed by a qualitative validation from researcher, adviser and farmer points of view, including simulations of prospective scenarios. [Copyright &y& Elsevier]

Abstract: A straightforward strategy is proposed to impart antimicrobial properties to biodegradable poly(oxepan-2-one) (poly(ɛ-caprolactone) or PCL), which is based on the grafting of pendant ammonium salts by “click” chemistry. First, statistical copolymerization of 3-chlorooxepan-2-one (α-chloro-ɛ-caprolactone or αClɛCL) with oxepan-2-one (ɛ-caprolactone or ɛCL) was initiated by 2,2-dibutyl-2-stanna-1,3-dioxepane (DSDOP). In a second step, pendant chlorides were converted into azides by reaction with sodium azide (NaN3). Finally, quaternary ammonium containing alkynes were quantitatively added to the pendant azide groups of PCL by the copper-catalyzed Huisgen''s 1,3-dipolar cycloaddition, which is a typical “click” reaction. An alternative two-step strategy based on the cycloaddition of the amine containing alkyne onto the pendant azides, followed by quaternization turned out to be less efficient. The antimicrobial activity was analyzed by the “shaking flask method” in the presence of Escherichia coli (E. coli). [Copyright &y& Elsevier]

Abstract: Copper-mediated azide–alkyne Huisgen''s 1,3-dipolar cycloaddition is a “click” reaction that was successfully used to prepare pH-responsive, amphiphilic and biodegradable networks. Indeed, this reaction proved to be very efficient in the “one pot” grafting of amino alkyne onto azide containing poly(ɛ-caprolactone) and the cross-linking of these chains by α,ω-dialkynyl poly(ethylene oxide). The pH-controlled release of guests hosted during the cross-linking step was illustrated with an entrapped model dye. [Copyright &y& Elsevier]

Summary: Sedentary endoparasitic nematodes are root parasites that interact with their hosts in a remarkable way. These obligate biotrophic pathogens establish an intimate relationship with their host plants, inducing the redifferentiation of root cells into specialized feeding cells. The successful establishment of feeding cells is essential for nematode development. Root-knot nematodes, of the genus Meloidogyne, have evolved strategies enabling them to induce feeding cell formation in thousands of plant species, probably by manipulating fundamental elements of plant cell development. Feeding cells enlarge and are converted into multinucleate giant cells through synchronous nuclear divisions without cell division. Fully differentiated giant cells may contain more than a hundred polyploid nuclei that may have undergone extensive endoreduplication. Hyperplasia and hypertrophy of the surrounding cells lead to the formation of the typical root gall. Giant cell formation requires extensive changes to gene expression. The induction of feeding cells remains poorly understood, but it is thought that effectors secreted by the nematode play a key role in parasitism, with potential direct effects on recipient host cells. In this review, we focus on the most recent investigations of the molecular basis of the plant–root-knot nematode interaction. Recently, microarray technology has been used to study the plant response to Meloidogyne spp. infection. Such a genome-wide expression profiling provides a global view of transcriptional changes, especially for genes involved in cell wall, transport processes and plant defense responses during giant cell formation. The identification of nematode-responsive plant genes constitutes a major step toward understanding how root-knot nematodes dramatically alter root development to induce and maintain giant cells. The characterization of nematode secretions as parasitism effectors and the development of RNAi technology should improve our understanding of the molecular events and regulatory mechanisms involved in plant parasitism. Finally, Meloidogyne genome sequences should provide further insight into plant–root-knot nematode interactions. [Copyright &y& Elsevier]

Abstract: The objective of this study was to identify precalving nutritional risk factors that may affect variation in first service conception risk in 21 commercial Holstein dairy herds in a tropical environment (Reunion Island). The data set included 473 lactation records in 404 cows. A multivariate logistic-regression model including herd as a random effect was used to analyse the relationship between first service conception risk and energy status (body condition score, plasma glucose, insulin, cholesterol, non-esterified fatty acids and β-hydroxybutyrate), nitrogen status (urea), hepatic function (γ-glutamyltransferase, glutamate deshydrogenase, albumin), and mineral deficiencies (calcium, phosphorus, magnesium), adjusting systematically for factors such as breeding, season, parity, previous milk yield and fertility, calving to first service interval and type of oestrus (spontaneous versus induced). The overall mean conception risk was 0.27±0.02 (mean±S.E.M., n =473). First service conception risk was penalized by calving to 1st service interval shorter than 60 days, synchronized oestrus, previous 305-day milk yield >8000kg (p <0.05), low blood glucose concentration in high-yielding cows (p <0.05) and combined high urea and β-hydroxybutyrate concentrations (p <0.01). Precalving energy imbalance, revealed by low prepartum glucose concentration, was a strong nutritional predictor of low first service conception risk in high-yielding cows. Some precalving nutritional disorders potentially associated with consumption of spoiled silage which induces elevated circulating urea and β-hydroxybutyrate have a delayed detrimental effect on conception, even if the true causes of this effect remain to be elucidated. As a conclusion, our findings should lead the breeders to pay more attention to the feeding of dry cows that is usually neglected in Reunion Island dairy farms. [Copyright &y& Elsevier]

Abstract: The comparison of organolanthanide complexes, (C5Me5)2SmMe(THF) (Sm1) and [(C5Me5)2Sm]2(PhCh name="dbnd" />C), with tin compounds, Bu2Sn(OMe)2 (Sn1) and Bu2Sn(OCH2CH2CH2O) (Sn2), in the preparation of random, diblock, and triblock copolymers composed of l-lactide (l-LA) or d, l-LA and cyclic carbonates, trimethylene carbonate (TMC) or 2,2-dimethyltrimethylene carbonate (DTC) is reported. The biodegradabilities of the resulting copolymers with proteinase K and a compost were examined. The copolymerization of l-LA with cyclic carbonates by Sm1 or Sm2 afforded copolymers with relatively low melting points (&#60;160°C) due to the accompanying epimerization in comparison with those obtained with Sn1 or Sn2. In the degradation of the polymers with a compost, the copolymers based on d, l-LA were more degradable than those based on l-LA. On the other hand, the effect of the incorporated cyclic carbonate on its degradability was more drastic in the copolymers based on l-LA than those in the copolymers based on d, l-LA. The introduction of only a small amount of the cyclic carbonates into PLLA significantly enhanced the degradability of PLLA with a compost or proteinase K. In the enzymatic degradation of l-LA-containing polymers, the copolymerization of l-LA with TMC was also quite effective to improve the degradability of PLLA. Triblock copolymerization tends to be effective to enhance the degradability of PLLA. [Copyright &y& Elsevier]

Plant-parasitic nematodes Meloidogyne spp induce an elaborate permanent feeding site characterized by the redifferentiation of root cells into multinucleate and hypertrophied giant cells. We have isolated by a promoter trap strategy an Arabidopsis thaliana formin gene, AtFH6, which is upregulated during giant cell formation. Formins are actin-nucleating proteins that stimulate de novo polymerization of actin filaments. We show here that three type-I formins were upregulated in giant cells and that the AtFH6 protein was anchored to the plasma membrane and uniformly distributed. Suppression of the budding defect of the Saccharomyces cerevisiae bni1Δ bnr1Δ mutant showed that AtFH6 regulates polarized growth by controlling the assembly of actin cables. Our results suggest that AtFH6 might be involved in the isotropic growth of hypertrophied feeding cells via the reorganization of the actin cytoskeleton. The actin cables would serve as tracks for vesicle trafficking needed for extensive plasma membrane and cell wall biogenesis. Therefore, determining how plant parasitic nematodes modify root cells into giant cells represents an attractive system to identify genes that regulate cell growth and morphogenesis. [ABSTRACT FROM AUTHOR]

The comparison of organolanthanide complexes, (C5Me5)2SmMe(THF) (Sm1) and [(C5Me5)2Sm]2(PhC&z.dbnd6;C&z.dbnd6;C&z.dbnd6;CPh) (Sm2), with tin compounds, Bu2Sn(OMe)2 (Sn1) and Bu2Sn(OCH2CH2CH2O) (Sn2), in the preparation of random and diblock copolymers composed of l-lactide (l-LA) or d,l-LA and #x03B5;-caprolactone (CL), and the preparation of triblock copolymers composed of l-LA/CL/l-LA was studied and the biodegradabilities of the resulting copolymers with proteinase K and a compost were examined. Poly(l-LA-ran-CL) shows much higher degradability than poly(l-LA) with proteinase K, and poly(l-LA), poly(l-LA-ran-CL) and poly(l-LA-b-CL) (b means block) prepared with Sm1 had better degradability than those synthesized with the Sn1 compound. The degradability of poly(l-LA-ran-CL) with proteinase K is higher than that of poly(l-LA-b-CL). Poly(LA-ran-CL) and poly(LA-b-CL) prepared with Sm1 revealed higher degradability than those obtained with Sn1 using a compost. Triblock copolymers, poly(l-LA-b-CL-b-l-LA), synthesized with Sm2 revealed nearly the same degradability with those obtained with Sn2 using a compost. Finally, biocompatibility was studied with macrophage activation assay using RAW 264.7, and metabolic viability assay using Cell Titer Aqueous non-radioactive Cell. [Copyright &y& Elsevier]

To characterize host genes required for a compatible interaction, we identified a novel recessive Arabidopsis thaliana mutant, nws1 (no wilt symptoms), that failed to develop wilt symptoms in response to virulent strains of the phytopathogenic bacterium, Ralstonia solanacearum. The absence of wilting in nws1 plants was not correlated with a cell death phenotype or a constitutive expression of salicylic acid-, jasmonic acid- or ethylene-associated genes. In addition, this mutation, which conferred a symptomless phenotype in response to all the R. solanacearum strains tested, was highly specific to this pathogen, because nws1 responses to other plant pathogens, including oomycetes, nematodes, viruses, and other bacteria, were identical to those of wild-type Col-5 plants. Finally, the lack of disease development was shown to be different than RRS1-R-mediated resistance. The identification of mutants such as nws1, that are unable to develop disease, should lead to the isolation of target host factors required for pathogen growth or fitness, or of factors modified by the invading microorganism to avoid or inactivate plant defense mechanisms, and should bring a better understanding of bacterial wilt diseases. [ABSTRACT FROM AUTHOR]

Fully biodegradable and surface-functionalized poly(D,L-lactide) (PLA) nanoparticles have been prepared by a co-precipitation technique. Novel amphiphilic random copolyesters P(CL-co-γ XCL) were synthesized by controlled copolymerization of ε-caprolactone and ε-caprolactone substituted in the γ-position by a hydrophilic X group, where X is either a cationic pyridinium (γ PyCL) or a non-ionic hydroxyl (γ OHCL). Nanoparticles were prepared by co-precipitation of PLA with the P(CL-co-γ XCL) copolyester from a DMSO solution. Small amounts of cationic P(CL-co-γ PyCL) copolymers are needed to quantitatively form stable nanoparticles (ca. 10 mg/100 mg PLA), although larger amounts of non-ionic P(CL-co-γ OHCL) copolymers are needed (&ges;12.5 mg/100 mg PLA). Copolymers with a low degree of polymerization (ca. 40) are more efficient stabilizers, probably because of faster migration towards the nanoparticle–water interface. The nanoparticle diameter decreases with the polymer concentration in DMSO, e.g. from ca. 160 nm (16 mg/ml) to ca. 100 nm (2 mg/ml) for PLA/P(CL-co-γ PyCL) nanoparticles. Migration of the P(CL-co-γ XCL) copolyesters to the nanoparticle surface was confirmed by measurement of the zeta potential, i.e. ca. +65 mV for P(CL-co-γ PyCL) and –7 mV for P(CL-co-γ OHCL). The polyamphiphilic copolyesters stabilize PLA nanoparticles by electrostatic or steric repulsions, depending on whether they are charged or not. They also impart functionality and reactivity to the surface, which opens up new opportunities for labelling and targeting purposes. [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol)-b-polyphosphoester (PEG-b-PPE) block copolymer nanoparticles are promising carriers for poorly water soluble drugs. To enhance the drug loading capacity and efficiency of such micelles, a strategy was investigated for increasing the lipophilicity of the PPE block of these PEG-b-PPE amphiphilic copolymers. A PEG-b-PPE copolymer bearing pendant vinyl groups along the PPE block was synthesized and then modified by thiol-ene click reaction with thiols bearing either a long linear alkyl chain (dodecyl) or a tocopherol moiety. Ketoconazole was used as model for hydrophobic drugs. Comparison of the drug loading with PEG-b-PPE bearing shorter pendant groups is reported evidencing the key role of the structure of the pendant group on the PPE backbone. Finally, a first evidence of the biocompatibility of these novel PEG-b-PPE copolymers was achieved by performing cytotoxicity tests. The PEG-b-PPE derived by tocopherol was evidenced as particularly promising as delivery system of poorly water-soluble drugs. [ABSTRACT FROM AUTHOR]