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There is a compelling need across several industries to substitute non-degradable, intentionally added microplastics with biodegradable alternatives. Nonetheless, stringent performance criteria in actives' controlled release and manufacturing at scale of emerging materials hinder the replacement of polymers used for microplastics fabrication with circular ones. Here, the authors demonstrate that active microencapsulation in a structural protein such as silk fibroin can be achieved by modulating protein protonation and chain relaxation at the point of material assembly. Silk fibroin micelles' size is tuned from several to hundreds of nanometers, enabling the manufacturing-by retrofitting spray drying and spray freeze drying techniques-of microcapsules with tunable morphology and structure, that is, hollow-spongy, hollow-smooth, hollow crumpled matrices, and hollow crumpled multi-domain. Microcapsules degradation kinetics and sustained release of soluble and insoluble payloads typically used in cosmetic and agriculture applications are controlled by modulating fibroin's beta-sheet content from 20% to near 40%. Ultraviolet-visible studies indicate that burst release of a commonly used herbicide (i.e., saflufenacil) significantly decreases from 25% to 0.8% via silk fibroin microencapsulation. As a proof-of-concept for agrochemicals applications, a 6-day greenhouse trial demonstrates that saflufenacil delivered on corn plants via silk microcapsules reduces crop injury when compared to the non-encapsulated version.

Starting from a theory of interpretation stating that legal interprets are free, the Théorie des contraintes (Theory of constraints) tries to isolate some specific factors that influence, determine or simply occur in the law-decision process. The “constraints” reduce the field of possibilities for authors producing a legal enouncement, decision, or reasoning. It's not synonymous of obligations in the common legal sense, defining an obligation as a set of duties imposed by legal norms. The concept of “constraints” is not conceived in the order of “sollen” (ought) but in the order of “sein” (is). The hypothesis is as follows: there are specific legal constraints that are different from moral, economical, psychological or social factors, and such constraints also determine the legal decisions. This paper aims to conceptualize the specificity of such constraints and to establish typologies in order to allow a more precized identification.

Recension de l’ouvrage de Karine Parrot, Carte blanche : l’Etat contre les etrangers, La fabrique editions, Paris, 2019, par Eric Millard.

The electrostatically driven self-assembly of oppositely charged gold nanoparticles (Au NPs) and polystyrene/poly(N-isopropylacrylamide) (PS/PNIPAm) core-shell microgels (CSMs) has been investigated. The co-assembly was accomplished by addition of smaller Au NPs to CSMs in dilute conditions up to a number ratio of about 1 : 1, when the suspension is destabilized. A combination of different techniques (i.e. turbidimetric titration, electrophoretic mobility, UV-visible spectroscopy, dynamic light scattering and microscopy techniques) were used to investigate the association between the two particles and the stability of the different mixtures. Hereby we demonstrate that the size ratio between the two particles (about 4 to 1) and the asymmetric character of the association result in the formation of electrostatic hybrid complexes, analogous to dipolar colloidal molecules, which further rearrange into finite sized clusters for number ratios NAuNPs/NCSMs < 1.

The ambient temperature (20 degrees C) reversible addition fragmentation chain transfer (RAFT) polymerization of several water-soluble monomers conducted directly in aqueous media under gamma-initiation (at dose rates of 30 Gy h(-1)) proceeds in a controlled fashion. Using functional trithiocarbonates, i e.. S,S-bis(alpha,alpha'-dimethyl-alpha ‘’-acetic acid) trithiocarbonate (TRITT), 3-benzylsulfanyl thiocarbonylsulfanyl propionic acid (BPATT). and dithioester, i e, 4-cyanopentanoic acid dithiobenzoate (CPADB), as chain transfer agents, fully water-soluble polymers of monomers such as N,N-dimethylacrylamide, 2-hydroxyethyl acrylate, acrylamide or oligo(ethylene glycol) methacrylate and stimuli-responsive polymers of monomers such as acrylic acid. N-isopropylacrylamide, 2-(dimethylamino)ethyl methacrylate or 2-acrylamido-2-methylpropane sulfonic acid can be obtained over a wide range of degrees of polymerization up to 10,000 with low polydispersity (typically (M) over bar (w)/(M) over bar (n) < 1 2) to near quantitative conversions Well-defined block copolymers between these monomers, based on several asymmetric macro-RAM agents, can be obtained, suggesting that the RAFT agents are stable throughout the polymerization process so that complex and well-defined architectures can be obtained. (C) 2010 Elsevier Ltd All rights reserved.

We present the synthesis of well-defined bis-hydrophilic block terpolymers with two outer hydrophilic blocks and an inner hydrophobic block together with studies concerning their colloidal aggregates formed in water. The investigations aim at preparation of dynamic micelles with tunable corona properties. Highly functionalized poly(ethylene oxide) macro-chain-transfer agents (PEO-CTAs) of two molecular weights (2 and 5 kDa) are used as mediating agents in reversible addition fragmentation chain transfer (RAFT) polymerization. The synthesis is accomplished by first polymerizing n-butyl acrylate as a hydrophobic block and then chain extending the diblock copolymers further with various (meth)acrylamide derivatives, acrylamide (AAm), N-isopropylacrylamide (NIPAAm), N,N-diethylacrylamide (DEAAm,) and N-(2-hydroxypropyl)methacrylamide (HPMA). Due to the high degree of functionalization of the PEO-CTA, the blocking efficiency is near quantitative and the diblock copolymers can be obtained easily in a wide range...

The ambient temperature (20 oC) reversible addition fragmentation chain transfer (RAFT) polymerization of N-isopropylacrylamide (NIPAAm) and acrylic acid (AA) conducted directly in aqueous media under gamma-initiation (at dose rate of 30 Gy h-1) proceeds in a controlled (typically Mw/Mn < 1.2) to near quantitative conversions and up to number-average molecular weights of 2.5 x 105 g . mol-1for PNIPAAm and 1.1 x 105 g . mol-1 for PAA via two water-soluble trithiocarbonate chain transfer agents, i.e., S,S-bis(α,α′-dimethyl-α″-acetic acid)trithiocarbonate (TRITT) and 3-benzylsulfanylthiocarbonylsulfanyl propionic acid (BPATT). The generated polymers are successfully chain extended, which suggests that the RAFT agents are stable throughout the polymerization process so that complex and well-defined architectures can be obtained.

We report on the use of binary mixtures of oppositely charged gold nanoparticles (AuNPs) and spherical polyelectrolyte brushes (SPBs), consisting of a polystyrene core onto which long polystyrene sulfonate chains are grafted, as a simple model system to investigate the influence of directional interactions on self-assembly. We demonstrate that the mixing ratio, i.e., the number of AuNPs per SPB, has a profound influence on self-assembly. In particular we report on the formation of giant hollow fibers, and present a thorough characterization of these nanostructures. We speculate that the adsorption of a few AuNPs on the SPBs appears to direct the tubular self-assembly, and discuss the analogy to the case of modified proteins such as tubulin under the action of nucleotides.

New Melatonin-loaded vesicular nanocarriers were prepared by interfacial deposition using a blend of an amphiphilic diblock copolymer, poly(methyl methacrylate)-block-poly(2-(dimethylamino)ethyl methacrylate), PMMA-b-PDMAEMA, with poly(epsilon-caprolactone), PCL. Particle size and morphology of the nanocarriers was evaluated. Dynamic light scattering shows that the nanocarriers have hydrodynamic radii between 100 and 180 nm, with unimodal particle size distribution for each formulation. Shape and structure were visualized by transmission electron microscopy (TEM), cryogenic TEM and scanning electron microscopy. Standard TEM for nanocapsules showed an oily core surrounded by a thin layer composed by PCL/PMMA-b-PDMAEMA. Cryo-TEM also indicated the presence of spherical nano-objects with a diffuse polymer corona. Encapsulation efficiencies were determined assaying the nanoparticles by HPLC and higher values of ca. 25% are shown by the nanocapsules. We could successfully incorporate platinum nanoparticles into the nanocarrier as evidenced by TEM, which opens up the possibility for promising applications like monitoring the encapsulated drug in the body.

Conclusion du rapport sur la Justiciabilité des droits sociaux rédigé par Diane Roman; International audience; Le caractère de la justiciabilité des droits sociaux, et le phénomène de leur judiciarisation, semblent désormais démontrés. Les études mettent en évidence ce qui est davantage qu'une tendance, au-delà des normales différences entre systèmes juridiques et cultures politico-sociales. Le présent texte envisage une question importante qui ne peut être occultée, et qui va au-delà de la mise au jour juridique et de l'analyse située des dispositifs et décisions : celle de la signification théorique et politique de cette tendance.

The coupling of the reversible addition fragmentation chain transfer (RAFT) polymerization technique with the copper-catalyzed Huisgen 1,3-dipolar cycloaddition ("click chemistry") as a simple and effective way to generate polystyrene (PS) macrocycles is presented. The novel strategy entails the synthesis of linear PS backbones followed by endgroup modification to facilitate click chemistry for the formation of ring shaped polymers. An azido group modified 4-cyanopentanoic acid dithiobenzoate is employed as the chain transfer agent in the RAFT mediated polymerization of styrene to form PS with M-n from 2000 g mol(-1) to 6000 g mol(-1) and PDI < 1.2. To facilitate the cyclization of the polystyrene chains by click coupling, the thiocarbonylthio endgroup is removed and concomitantly replaced by an alkyne bearing function. This is carried out via the radical decomposition of excess azobis(4-cyano valeric acid) (ACVA) modified with an alkyne endgroup in the presence of the thiocarbonylthio-capped PS. The successful click endgroup modifications of several polystyrenes along with the results from the cyclization of a PS with M-n = 4300 g mol(-1) are discussed in detail. This improved method avoids the presence of thiocarbonylthio functions in the macrocycle, thus considerably increasing the chemical stability of these polymers. (C) 2008 Elsevier Ltd. All rights reserved.

3 propositions iconoclastes pour l'avenir de la politique familiale, en réponse à l'appel d'offre de la revue de la CNAF

The French situation might appear to be a paradox when studying women in constitutional law. On the one hand, the Constitution of 1958, as amended, has not fundamentally altered women's constitutional status. The prevailing principle of republican universalism, conceived during the French Revolution in 1789, remains the key notion in the constitutional debate and the inspiration of all legal provisions. On the other hand, a recent constitutional reform vested parliament with the power to organize a “parity” or strict gender equality, democracy. This power resulted in the enactment of a statute requiring that, under certain conditions, an equal number of male and female candidates must appear on the lists submitted to voters for most elections. From this point of view, the French experience could appear a very innovative one. France has a civil law system, with a clear separation between civil and administrative law (the former is codified for most issues, the latter is closer to case law) and separate adjudicative bodies (namely, the Cour de cassation [civil] and the Conseil d'Etat [administrative]). Insofar as most matters pertaining to women's legal status are governed by written texts (the Constitution, regular statutes, and sometimes administrative rules), adjudicative bodies are generally limited to applying those texts to concrete cases without creating new law. The current Constitution is known as the Constitution of the Vth Republic. Adopted in 1958, it established a system of government that is sometimes characterized as a “presidential” system and sometimes as a “unique parliamentary system.”

This paper intends to establish the reasons why there is no consistent conception of the science of legislation in Ross's works.

The paper aims at working out a comparison between the philosophical outlook known as logical positivism, on the one hand, and the jurisprudential movement known as legal realism, on the other. After having pointed out the methodological difficulties of such an undertaking, the author, on the basis of examples taken from Ross, Olivecrona, and the American realists, scrutinizes the tendency to downsizing the conceptual originality of Scandinavian legal realism, in front of its purported aim of developing a legal theory deeply affected by the tenets of logical positivism. Finally, the author focusses on present-day legal realism, claimimg it is a post-logical positivism project, both from a metaethical, and from a theoretical and strategic viewpoint.; Cet article a pour objectif de rapprocher le courant philosophique du positivisme logique et le courant du réalisme juridique en théorie du droit. Après avoir indiqué les difficultés méthodologiques d'un tel exercice, l'auteur suit, à partir d'exemples tirés de Ross, d'Olivecrona et du réalisme américain, la tendance qui conduit à dépasser l'originalité conceptuelle du réalisme juridique scandinave par la déclinaison dans le champ de la théorie du droit des positions essentielles du positivisme logique. Finalement; il est proposé de considérer le réalisme actuel comme un projet post-positiviste logique, aussi bien d'un point de vue méta éthique que théorique et stratégique

The paper aims at working out a comparison between the philosophical outlook known as logical positivism, on the one hand, and the jurisprudential movement known as legal realism, on the other. After having pointed out the methodological difficulties of such an undertaking, the author, on the basis of examples taken from Ross, Olivecrona, and the American realists, scrutinizes the tendency to downsizing the conceptual originality of Scandinavian legal realism, in front of its purported aim of developing a legal theory deeply affected by the tenets of logical positivism. Finally, the author focusses on present-day legal realism, claimimg it is a post-logical positivism project, both from a metaethical, and from a theoretical and strategic viewpoint., Cet article a pour objectif de rapprocher le courant philosophique du positivisme logique et le courant du réalisme juridique en théorie du droit. Après avoir indiqué les difficultés méthodologiques d'un tel exercice, l'auteur suit, à partir d'exemples tirés de Ross, d'Olivecrona et du réalisme américain, la tendance qui conduit à dépasser l'originalité conceptuelle du réalisme juridique scandinave par la déclinaison dans le champ de la théorie du droit des positions essentielles du positivisme logique. Finalement; il est proposé de considérer le réalisme actuel comme un projet post-positiviste logique, aussi bien d'un point de vue méta éthique que théorique et stratégique

International audience; L'article traite de l'articulation entre le travail scientifique et les convictions du citoyen en s'interrogeant sur l'impact du positivisme, sur les notions d'objectivité et d'impartialité, et finalement sur les dilemme de l'universitaire, y compris face à ses étudiants.