Polypyrrole materials doped with weakly coordinating anions: influence of substituents and the fate of the doping anion during the overoxidation process

The influence of weakly coordinating anions with different shapes and substituents has been studied to get the overoxidation resistance limit of the material, ORL. The anions utilized are derivatives of [Co(C₂B₉H₁₁)₂]⁻, [B₁₂H₁₂]²⁻ and [B₁₂H₁₁NH₃]⁻. The following tendencies have been established (1) boron cluster monoanions are to date the anions that offer the highest stability to overoxidation of PPy doped materials (2) the ORL stability of the material can not be attributed only to the shape of the cluster (3) monoanionic clusters are far superior than dianionic to get an ORL rise (4) cluster charge density reduction results in ORL rise as has been observed in [Co(C₂B₉H₁₁)₂]⁻ after incorporation of electron-withdrawing substituents with no electron back-donation (5) globular, rigid and large monoanions are less suitable for enhanced ORL values than elongated and non-rigid species (6) adequate anion's substitution produce a rise in the ORL of the material, thus polyether side-arms are beneficial with [Co(C₂B₉H₁₁)₂]⁻, whereas, T-shaped methylaryl groups are appealing in [B₁₂H₁₁NH₃]⁻ based materials, respectively, (7) substituents on the anions usually imply higher difficulty in the materials' growth. The high boron contents in these materials has permitted to learn on the fate of the doping anions during the overoxidation process. There is a built-up of the concentration of the doping anion in the electrolyte near surface area, whereas, a depletion is observed in the nearest inner layers.     

Effectiveness of antioxidants in preventing oxidation of palm oil enriched with heme iron: A model for iron fortification in baked products

Bakery products such as biscuits, cookies, and pastries represent a good medium for iron fortification in food products, since they are consumed by a large proportion of the population at risk of developing iron deficiency anemia, mainly children. The drawback, however, is that iron fortification can promote oxidation. To assess the extent of this, palm oil added with heme iron and different antioxidants was used as a model for evaluating the oxidative stability of some bakery products, such as baked goods containing chocolate. The palm oil samples were heated at 220°C for 10 min to mimic the conditions found during a typical baking processing. The selected antioxidants were a free radical scavenger (tocopherol extract (TE), 0 and 500 mg/kg), an oxygen scavenger (ascorbyl palmitate (AP), 0 and 500 mg/kg), and a chelating agent (citric acid (CA), 0 and 300 mg/kg). These antioxidants were combined using a factorial design and were compared to a control sample, which was not supplemented with antioxidants. Primary (peroxide value and lipid hydroperoxide content) and secondary oxidation parameters (p‐anisidine value, p‐AnV) were monitored over a period of 200 days in storage at room temperature. The combination of AP and CA was the most effective treatment in delaying the onset of oxidation. TE was not effective in preventing oxidation. The p‐AnV did not increase during the storage period, indicating that this oxidation marker was not suitable for monitoring oxidation in this model.     

High temperature lithium cells using conversion oxide electrodes

Oxidized stainless steel electrodes containing chromium oxides without any conducting additives or binder have been successfully cycled at high temperatures (up to 100 °C) in organic solvent-based electrolytes with high reversibility. Cycling at high temperature results in an enhancement of the capacity at lower voltages, which is maintained upon cycling. After studying different electrolyte candidates, the best results were obtained using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) dissolved in ethylene carbonate.     

In Vitro Characterization of Human CD24hiCD38hi Regulatory B Cells Shows CD9 Is Not a Stable Breg Cell Marker

Regulatory B (Breg) cells are endowed with immune suppressive functions. Various human and murine Breg subtypes have been reported. While interleukin (IL)-10 intracellular staining remains the most reliable way to identify Breg cells, this technique hinders further essential functional studies. Recent findings suggest that CD9 is an effective surface marker of murine IL-10 competent Breg cells. However, the stability of CD9 and its relevance as a unique marker for human Breg cells, which have been widely characterized as CD24^hiCD38^hi, have not been investigated. Here, we demonstrate that CD9 expression is sensitive to in vitro B cell stimulations. CD9 expression could either be re-expressed or downregulated in purified CD9-negative B cells and CD9-positive B cells, respectively. We found no significant differences in the Breg differentiation capacity of the CD9-negative and CD9-positive B cells. Furthermore, CD9-positive B cells co-express CD40 and CD86, suggesting their nature as B cell activation or co-stimulatory molecules, rather than regulatory ones. Therefore, we report the relatively unstable CD9 as a distinct surface molecule, indicating the need for further research for a more reliable marker to purify human Breg cells.     

Fenton and photo‐Fenton oxidation of a model mixture of dyes – overall kinetic analysis

The decolorisation and mineralisation of a model mixture of reactive dyes, under Fenton and photo‐Fenton conditions, have been investigated. A kinetic study was performed and rate constants and half‐life times determined from batch experimental data according to a pseudo‐first‐order degradation kinetic model. Moreover, the use of natural or artificial light, as well as the effect of temperature, was evaluated with the aim of finding the best Fenton process to promote the efficient degradation of the standard trichromatic system. The experimental results showed that the Fenton process run under solar light was the most effective. It is suggested that Fenton‐ and photo‐Fenton‐type reactions are viable techniques for the treatment of these types of dye mixtures, according to the high levels of colour, chemical oxygen demand and total organic carbon removal.     

Physico-chemical properties, composition and pollen spectrum of french lavender (Lavandula stoechas L.) honey produced in Spain

The palynological and physico-chemical properties of 26 samples of French lavender (Lavandula stoechas) honey commercially produced in Spain have been defined. Each sample was examined to determine the total pollen content, percentage ofL. stoechas pollen and pollen spectrum. On the basis of the honey pollen analysis, 14 samples were excluded as they were of different botanical origin (Echium spp.). In total 67 different pollen types were identified. The sugar spectrum showed low percentages of trisaccharides and sucrose. The enzymatic activity was lower than that found in other unifloral Spanish honeys. A minimum of 10%L. stoechas pollen and maximum of 30%Echium sp. pollen are the suggested requirements to characterize this honey.

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Zusammensetzung, physikalisch-chemische Eigenschaften und Pollenspektrum im spanischen Heidehonig (Lavandula stoechas L.)

Zusammenfassung Anhand von 26 Stichproben wurden die physikalisch-chemischen Eigenschaften und das Pollen-Spektrum des kommerziell vertriebenen spanischen Heidehonigs (Lavandula stoechas L.) bestimmt. Jede Stichprobe wurde auf den Gesamtgehalt an Pollen sowie den prozentualen Anteil an Pollen desL. stoechas und auf das Pollen-Spektrum untersucht. Aufgrund der Analyse des Melissen-Spektrums mußten 14 Stichproben ausgeschlossen werden, da sie unterschiedlichen botanischen Ursprungs waren (Echium spp.). Es wurden 67 verschiedene Pollenarten identifiziert. Das Zuckerspektrum wies einen geringen Anteil an Trisacchariden und Sucrose auf. Die enzymatische Aktivität dieser Honigarten war geringer bei anderen Blütenpflanzen. Als Mindestmenge an Pollen desL. stoechas werden 10% vorgeschlagen, und ein Pollenanteil von <30% beiEchium sp. ist für diesen Honig charakteristisch.

     

Distributing game instances in a hybrid client-server/P2P system to support MMORPG playability

MMORPG (Massively Multiplayer Online Role Playing Games) is the most popular genre among network gamers, and now attract millions of users, who play simultaneously in an evolving virtual world. This huge number of concurrent players requires the availability of high performance computation servers. Additionally, gaming aware distribution mechanisms are needed to distribute game instances among servers to avoid load imbalances that affect performance negatively. In this work, we tackle the problem of game distribution and scalability by means of a hybrid Client-Server/P2P architecture that can scale dynamically according to the demand. To manage peak loads that occur during the game, we distribute game computation across the system according to the behavior of MMORPGs. We distinguish between the computation associated with the Main Game, that affects all players, and the computation of Auxiliary Games that affects only a few players and acts in isolation from the execution of the Main Game. Taking this distinction into account, we propose a mechanism that is focused in the distribution of Auxiliary Games, as an entity, across the pool of servers and peers of the underlying hybrid architecture. We evaluate the performance of the balancing mechanism taking the criteria of latency and reliability into account, and we compare the effectiveness of the mechanism with a classic approach that applies load balancing to individually players in a Client-Server system. We show that the balancing mechanism based on the latency criteria provides lower latency than the classical proposal, while in relation to reliability, we obtain a failure probability of under 0.9 % in the worst case, which is amply compensated by the scalability provided by the use of the P2P area.