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Spherification methods to produce particles of millimetric size are detailed in this review, especially for encapsulation purpose and using alginate. Therefore, alginate properties and factors impacting its gelation, counting its structure and experimental conditions such as pH, temperature, crosslinker concentration, residence time and ionic strength, are largely discussed. Furthermore, the interest for using co-polymer in spherification is investigated. Thereby, alginate composite gels can enhance encapsulation efficiency, mechanical stability, barrier properties and thermal stability. The advantages and limitations of their use are discussed for each spherification process to improve the knowledge about alginate versatility. Alginate is still one of the most promising encapsulation materials.

Oil-alginate capsules were produced by annular jet breaking coextrusion. Effects of alginate flow rate (30–50 mL/min), oil flow rate (4–18 mL/min), applied frequency (80–200 Hz), calcium concentration (1.5–50 g/L) and alginate solution age (24–72 h) and their interactions, on capsules shape and encapsulation payload were studied using response surface method. Analysis exhibited that capsules size was inversely proportional to calcium concentration and frequency. Small capsules presented higher core centricity index while alginate ageing does not have significant effect of the studied responses. Encapsulation payload was strongly related to alginate network structure and influenced by calcium concentration. Multi-response method was performed to produce an optimum model and a phenomenological model was successfully applied to model the effects of CaCl2 and alginate flow rate on beads volume to facilitate further industrial applications.

To enhance physico-chemical properties of alginate liquid-core capsules, shellac was incorporated into the membrane (composite capsules) or as an additional external layer (coated capsules). The influence of pH, coating time, shellac concentration and preparation mechanism (acid or calcium precipitation) were investigated. Results showed that shellac significantly influenced the capsules properties. The feasibility of shellac incorporation was closely related to the preparation conditions as confirmed by Infrared spectroscopy. Optical, fluorescence and scanning electron microscopy, highlighted different capsules and membranes architectures. In contrast to simple and composite capsules, coated capsules showed a pH-dependent release of the entrapped vitamin especially after shellac crosslinking with calcium. Heating of coated capsules above the glass transition temperature investigated by Differential Scanning Calorimetry, led to irreversible structural change due to thermoplastic behavior of shellac and enhanced riboflavin retention under acidic conditions. This global approach is useful to control release mechanism of low molecular weight molecules from macro and micro-capsules.

International audience; Hypothesis: Alginate capsules have several applications. Their functionality depends considerably on their permeability, chemical and mechanical stability. Consequently, the creation of composite system by addition of further components is expected to control mechanical and release properties of alginate capsules. Experiments: Alginate and alginate-sodium caseinate composite liquid-core capsules were prepared by a simple extrusion. The influence of the preparation pH and sodium caseinate concentration on capsules physico-chemical properties was investigated. Findings: Results showed that sodium caseinate influenced significantly capsules properties. As regards to the membrane mechanical stability, composite capsules prepared at pH below the isoelectric point of sodium caseinate exhibited the highest surface Young's modulus, increasing with protein content, explained by potential electrostatic interactions between sodium caseinate amino-groups and alginate carboxylic group. The kinetic of cochineal red A release changed significantly for composite capsules and showed a pH-responsive release. Findings: Sodium caseinate-dye mixture studied by absorbance and fluorescence spectroscopy confirmed complex formation at pH 2 by electrostatic interactions between sodium caseinate tryptophan residues and cochineal red sulfonate-groups. Consequently, the release mechanism was explained by membrane adsorption process. Findings: This global approach is useful to control release mechanism from macro and micro-capsules by incorporating guest molecules which can interact with the entrapped molecule under specific conditions.

Hypothesis To enhance physicochemical properties of alginate aqueous-core capsules, conventional strategies were focused in literature on designing composite and coated capsules. In the present study, own effect of liquid-core composition on mechanical and release properties was investigated. Experiments Capsules were prepared by dripping a CaCl2 solution into an alginate gelling solution. Viscosity of CaCl2 solution was adjusted by adding cationic, anionic and non-ionic naturally derived polymers, respectively chitosan, xanthan gum and guar gum. In parallel, uniform alginate hydrogels were prepared by different methods (pouring, in situ forming and mixing). Mechanical stability of capsules and plane hydrogels were respectively evaluated by compression experiments and small amplitude oscillatory shear rheology and then correlated. Capsules permeability was evaluated by monitoring diffusion of encapsulated cochineal dye, riboflavin and BSA. The core–shell interactions were investigated by ATR-FTIR. Findings Results showed that inner polymer had an impact on membrane stability and could act as an internal coating or provide mechanical reinforcement. Mechanical properties of alginate capsules were in a good agreement with rheological behavior of plane hydrogels. Release behavior of the entrapped molecules changed considerably. This study demonstrated the importance of aqueous-core composition, and gave new insights for possible adjusting of microcapsules physicochemical properties by modulating core–shell interactions.

The interplay of chemical and mechanical effects is of crucial importance for understanding and solving key problems of geology, engineering and environmental science. We begin with an outline of the governing equations for a coupled multicomponent reactive transport model. Thermal coupling and heat flow is also considered. The reaction part of the model is kept very general and applies to a wide variety of problems including simulation of in situ leaching, mineralization (ore body genesis), environmental hazards and calcite leaching to name just a few. We briefly introduce the CSIRO symbolic finite element solver FASTFLO (http://www.cmis.csiro.au/fastflo) and illustrate the theory by a number of finite element solutions. While focussing initially on reactive transport dominated problems (deformation and damage negligible) we close with a limit load problem involving chemically induced reduction of the yield strength. We consider a stiff, smooth strip foundation on an infinite half plane (Prandtl case). The substrate deforms and partially plastifies (von Mises yield, Prandtl-Reuss flow rule). We then prescribe a constant concentration of a leachant on the surface of the half plane. The concentration of the leachant diffuses through the half plane, lowering the yield strength and ultimately causing unacceptably large deformation of the structure.

Annual Report on European SMEs: A Recovery on the Horizon?2013 is likely to mark a turning point for the EU SMEs. After five years of an uncertain economic environment, 2013 is expected to be the first year since 2008 with a combined increase in aggregated employment and value-added of EU’s SMEs. The total employment in the EU SMEs is expected to increase by 0.3% and value-added by 1% as compared to 2011. Preliminary forecasts expect the positive developments further accelerating in 2014. These promising projections are backed up by other positive signals. Over the last three years, an increasing number of Member States have seen their small business sectors returning to an expansion of employment and value-added, or at least a petering out of the decline. If the macroeconomic conditions hold, this development would mark the end of the most challenging crisis the European SMEs have experienced in the recent history. Viewed against the unparalleled depth and complexity of the crisis, such a turn-around is a remarkable testimony to the resilience of the EU SMEs. While in 2008-2011 the SMEs resisted the crisis better than large enterprises, in 2012 SMEs suffered a loss of jobs in the order of 610,000 jobs or a 0.7% decrease compared to 2011. Moreover, SMEs’ contribution to GDP declined by 1.3% from €3.44 trillion in 2011 to €3.39 trillion in 2012. A further consequence of the crisis was that the distribution of losses in employment and value added was very unevenly distributed among the Member States. About half of the 27 EU Member States created new employment in 2012, adding roughly 0.5 million net jobs to the employment stock in their respective sectors. The losses of jobs in SMEs are heavily concentrated in the more vulnerable Member States still affected by the sovereign debt crisis. However, even in their case the decline has slowed down significantly, indicating that the small businesses are bottoming out. European SMEs were significantly more resilient than large enterprises to the 2008 crisis, particularly in employment terms. However, after the crisis it has been more difficult also for them to recover. After 2009, large enterprises were leading the recovery in terms of output (gross value added), but as of 2012 they have surpassed SMEs – albeit only slightly - also in terms of employment. Thus, by 2012, large enterprises managed to regain almost 1.1 million of the 1.6 million jobs lost in 2009. The SMEs, which lost comparatively fewer jobs in preceding years, went through a rough patch in 2012. SMEs also trail behind large enterprises in terms of value added, since the latter have been faster to recover after 2009 and were somewhat less affected by the slowdown in 2012. Whilst large enterprises posted a decline in value added of €8.6 billion in 2012, medium-sized enterprises posted the highest loss in value added amounting to €17 billion, followed by micro-enterprises (€14 billion) and small-sized enterprises (€13.2 billion). The difference between the value added performance of SMEs and large enterprises over the period 2008 to 2012 reflects the weakness in domestic demand, which is a key market driver for SMEs, while large enterprises benefited from a better export performance. However, as domestic demand is expected to recover to some extent in 2013 and 2014, SMEs are forecast to perform somewhat similar to large enterprises over these two years.The SMEs in the service sectors, characterised by lower barriers to entry, performed better than SMEs in the manufacturing sector. 2012 was characterised by a decline in employment and value added by manufacturing SMEs. The one exception to these negative trends was a marginal increase in the number of medium-low tech manufacturing SMEs. At the same time, the number of SMEs in the knowledge intensive service sectors (KIS) grew in all SME size classes between 2008 and 2012. During the same period, employment in KIS SMEs grew at comparable rates with large enterprises (circa 4%). Similarly, SMEs in the high-tech KIS sectors posted a substantial increase in value added between 2008 and 2012. The poor performance of SMEs in the manufacturing sector is explained by the sharp decline of investments in capital formation and innovation caused by difficult credit conditions and the weakness of domestic demand. Indeed, the services provided to large businesses and other organisations by SMEs were less affected by tight credit conditions and, consequently, SMEs in the services sector started recovering in 2009. However, in 2013 and 2014 SMEs in the manufacturing sector are expected to undergo a significant recovery in terms of employment and somewhat less so in value added. SMEs in the service sectors, independently of the knowledge content of the services provided, are forecast to post positive growth rates in employment and value-added.The improvements in SMEs’ performance are underpinned by an impressive number of policy measures by the EU and the Member States since 2008. These policy developments, taken under the umbrella of the Small Business Act (SBA) for Europe have been instrumental in mitigating the effects of the crisis and in creating a pro-SME policy momentum across the European Union. In 2010-2012 only, the EU’s Member States implemented a total of almost 2,400 policy measures to support SMEs, i.e. an average of 800 measures per year, and almost 90 measures per country. Nevertheless, as evidenced by statistics, SMEs are still bearing the brunt of the crisis more than large enterprises. This calls for a move into top gear in SME policy making and to give a necessary boost to the green sprouts of recovery. Some of the essential ingredients required for SMEs to recover and prosper include harmonised policies, improved conditions to access finance, strong public demand for the goods and services produced by SMEs, an appropriate attention to labour market policies, a decrease in late payments, and simpler regulatory and administrative requirements. In fact, as evidenced in the third chapter of the report, countries characterised by a business friendly environment, a modern infrastructure, technologically advanced sectors and a highly skilled workforce are expected to recover much faster to pre-crisis levels.