Effect of selected ions from lyotropic series on lipid oxidation rate

Organic or inorganic salts, commonly present in foods as natural components or ingredients, can affect the hydrophobic/hydrophilic interactions among food components. In particular, modifying the physicochemical equilibrium in the media, the ionic species forming salts could affect the kinetics of chemical reactions occurring in foods. The aim of the present research was to study the influence of different ionic species from lyotropic series on the kinetics of lipid oxidation. For this purpose, salts containing antichaotropic (carbonate and acetate), neutral (Na⁺, K⁺) and chaotropic ions (Cl⁻) were added to soybean oil. Results indicate that potassium carbonate and potassium acetate present a strong antioxidant capacity, whereas no effect was detected for NaCl and KCl. The salt antioxidant activity was prevalently attributed to the antichaotropic anionic species present in the media, which could interact with hydroperoxides by virtue of their ability to form hydrogen bonds. These results appear to be of considerable interest for controlling the development of rancidity in foods.     

Cross-national differences in consumer responses to savoury crackers containing blackcurrant pomace

Juice-pressing residues, among them blackcurrant pomace, are valuable materials for being upgraded in food products. Their excellent nutritional profiles in line with their functional properties allow a wide range of applications. The current study was performed to evaluate the overall liking of a pomace-enriched thin crispy-baked bread product in five European countries, and to obtain suggestions for improvements. Moreover, data on the frequency of snack consumption, openness to new foods and an opinion on residues in food applications were acquired. Four hundred and sixty-six consumers from United Kingdom, Spain, Sweden, Italy and Germany were involved. On a 9-point hedonic scale, the pomace cracker was rated towards the direction of liking with 5.94 ± 1.90 on average. Contingency tables showed that the overall-liking correlated highly significant (p < 0.01) with the country of origin and sex of the respondents and their openness to new products. Significantly higher liking scores were provided by British and Spanish consumers and, among these respondents, savoury snacks were stated to be consumed most frequently. Therefore, the snack consumption frequency also appeared to be a driver for cross-national differences in hedonic responses. The consent for using pomace in food products was remarkably high (>90%) in all countries and stresses consumer awareness in terms of healthy longevity and sustainability.     

Satisfaction and switching intention in mobile services: Comparing lock-in and free contracts in the Spanish market

Switching costs are a relevant issue affecting market competition in the mobile services industry. However, customer switching costs have not disappeared, since numerous leading mobile services companies use lock-in strategies, such as obliged long-term contractual relationships. The present study provides and empirically test a conceptual model in order to analyze the creation of customer satisfaction and switching intention with mobile services, as well as to examine the differences between lock-in and free contracts in a South European mature market – Spain. For this purpose, drawing on a sample of 370 customers, we developed Structural Equation Modeling (SEM) through a multi-group analysis. Our findings suggest that service quality is one of the key determinants of satisfaction, while the availability of attractive alternatives is the main switching barrier. Moreover, some interesting differences were found between the two type of contracts analyzed. Consequently, we suggest shifting resources to customer retention through improved service quality for reducing customer churn rate.     

Thermodynamic assessment of the Sn-Co lead-free solder system

The Sn-Co-Cu eutectic alloy can be a less expensive alternative for the Sn-Ag-Cu alloy. In order to find the eutectic solder composition of the Sn-Co-Cu system, the Sn-Co binary system has been thoroughly assessed with the calculation of phase diagram (CALPHAD) method. The liquid phase, the FCC and HCP Co-rich solid solution, and the BCT Sn-rich solid solution have been described by the Redlich-Kister model. The Hillert-Jarl-Inden model has been used to describe the magnetic contributions to Gibbs energy in FCC and HCP. The CoSn₂, CoSn, Co₃Sn_{2_}β, and Co₃Sn_{2_}α phases have been treated as stoichiometric phases. A series of thermodynamic parameters have been obtained. The calculated phase diagram and thermodynamic properties are in good agreement with the experimental data. The obtained thermodynamic data was used to extrapolate the ternary Sn-Co-Cu phase diagram. The composition of the Sn-rich eutectic point of the Sn-Co-Cu system was found to be 224°C, 0.4% Co, and 0.7% Cu.     

Gated Mesoporous Silica Nanoparticles Using a Double‐Role Circular Peptide for the Controlled and Target‐Preferential Release of Doxorubicin in CXCR4‐Expresing Lymphoma Cells

B‐cell non‐Hodgkin's lymphoma (B‐NHL) is the most frequent malignant lymphoid neoplasm, which has a high degree of relapse and chemoresistance. Thus, strategies to improve currently used therapies are needed. In this context, a new CXCR4‐targeted delivery system is described using mesoporous silica nanoparticles (MSNs) that are loaded with doxorubicin and capped with a derivative of the T22 peptide (P). This design makes full use of the great affinity of the T22 peptide to CXCR4 receptor, which is overexpressed in lymphoma cells. The peptide is able to guide the gated nanoparticle to B‐NHL cells to facilitate MSNs uptake via the CXCR4 receptor. The endocyted P‐capped MSNs are also opened by endosomal proteolytic enzymes to allow intracellular doxorubicin delivery.     

Cognitive radio signal classification based on subspace decomposition and RBF neural networks

Spectrum sensing is one of the major challenges for commercial development of cognitive radio systems, since the detection of the presence of a primary user is a complex task that requires high reliability. This work proposes a signal classifier capable of detecting and identifying a primary user signal on a given channel of the radio spectrum. The proposed approach combines eigen-decomposition techniques and neural networks not only to decide about the presence of a primary user, but also to identify the primary user signal type, a feature that is not encountered in the current approaches proposed in literature. Besides the advantage of identifying the primary user type, the proposed method also considerably reduces the computational cost of the detection process. The proposed classification method has been applied to the development of five primary user signal Classification Modules, which includes wireless microphone, orthogonal frequency-division multiplexing and Digital Video Broadcasting-Terrestrial signals. The results show that the proposed classifier correctly detects and identifies the primary users, even under low signal to noise ratio and multipath scenarios.     

Self‐Assembling Azaindole Organogel for Organic Light‐Emitting Devices (OLEDs)

This study reports on the use of a self‐assembling organogel, 5‐(4‐nonylphenyl)‐7‐azaindole ( 1 ), as a new emitter in small‐molecule organic light emitting devices (OLEDs). The theoretical calculations along with the photophysical characterization studies suggest the coexistence of the monomer and dimer species at high concentration of compound 1 . The presence of this type of dimer (formed via H‐bonding) is responsible for the increased emission. However, the most notable feature is the 3D network of vastly interconnected fibers formed in the organogel that modifies the photophysical properties. Based on this, several OLED architectures are made in order to understand the mechanism involved in the electroluminescence (EL) behavior of 1 . Although the position of the EL spectra differs from that of the photoluminescence (PL) spectra, the trends observed in the device properties perfectly match with dimer formation. In this framework a better device performance is associated to a higher efficiency of dimer formation, which optimizes in the OLED prepared from the organogel. Therefore, these results show that the rational combination of a moiety showing a strong PL intensity increased upon aggregation with organogel properties is an efficient strategy to create alternative emitters for OLED devices.     

A Hydrogel Platform that Incorporates Laminin Isoforms for Efficient Presentation of Growth Factors – Neural Growth and Osteogenesis

Laminins (LMs) are important structural proteins of the extracellular matrix (ECM). The abundance of every LM isoform is tissue-dependent, suggesting that LM has tissue-specific roles. LM binds growth factors (GFs), which are powerful cytokines widely used in tissue engineering due to their ability to control stem cell differentiation. Currently, the most commonly used ECM mimetic material in vitro is Matrigel, a matrix of undefined composition containing LM and various GFs, but subjected to batch variability and lacking control of physicochemical properties. Inspired by Matrigel, a new and completely defined hydrogel platform based on hybrid LM-poly(ethylene glycol) (PEG) hydrogels with controllable stiffness (1–25 kPa) and degradability is proposed. Different LM isoforms are used to bind and efficiently display GFs (here, bone morphogenetic protein (BMP-2) and beta-nerve growth factor (β-NGF)), enabling their solid-phase presentation at ultralow doses to specifically target a range of tissues. The potential of this platform to trigger stem cell differentiation toward osteogenic lineages and stimulate neural cells growth in 3D, is demonstrated. These hydrogels enable 3D, synthetic, defined composition, and reproducible cell culture microenvironments reflecting the complexity of the native ECM, where GFs in combination with LM isoforms yield the full diversity of cellular processes.