FORMATION, CHARACTERIZATION, AND UTILIZATION OF MULTILAYER NANOEMULSIONS IN FOODS

Multilayer coatings have been proposed as a promising nanotechnology for improving the performance of emulsion-based products in numerous research fields. In foods, these multilayer coatings can be used to improve the encapsulation and protection of bioactive ingredients in delivery systems during storage and passage through the gastrointestinal tract (1, 2). Therefore, there is strong interest in understanding the formation, properties, and performance of these novel coatings. Multilayer coatings are formed by layer-by-layer electrostatic deposition of oppositely charged biopolymers, such as proteins and polysaccharides. A better understanding of the formation and properties of biopolymer multilayer coatings could lead to novel foods with improved performance. The purpose of this research was to improve our understanding of the fabrication and behavior of multilayer nanoemulsions suitable for application in the food industry. First, the interaction of anionic ɣ-poly-glutamic acid (PGA) and cationic ɛ-poly-L-lysine (PLL) in solution was examined so as to better understand their behavior at interfaces. Electrostatic complexes were formed with a 1:4 mass ratio of polyanion-to-polycation at saturation (pH 7.4). The surface potential and aggregation stability of the complexes was highly dependent on solution pH (2 to 12), which was attributed to alterations in the electrical characteristics of the two polyelectrolytes. In particular, insoluble complexes were formed under pH conditions where there was a strong electrostatic attraction between the two polyelectrolytes, whereas soluble complexes were formed when there was only a weak attraction. The addition of salt (³ 20 mM NaCl) promoted aggregation of the complexes, presumably due to screening of the electrostatic interactions between them. Conversely, temperature (25 to 90 oC) did not have a major impact on the stability of the complexes. These results may be useful for the design of effective oral delivery systems for bioactive agents in foods and other products. Secondly, the same biopolymers were used to form multilayer coatings around the lipid droplets in oil-in-water nanoemulsions using a sequential layer-by-layer electrostatic deposition approach. Cationic poly-L-lysine (PLL) and anionic poly-glutamic acid (PGA) were used as a pair of oppositely charged polypeptides (pH 4.0). First, a primary emulsion (10% w/w soybean oil-in-water emulsion) was formed consisting of small lipid droplets (d32 = 500 µm) coated by a natural surfactant (0.05% w/w quillaja saponin). Then, cationic PLL was deposited onto the surfaces of the anionic saponin-coated droplets. Lastly, anionic PGA was deposited onto the surfaces of the cationic PLL-saponin-coated droplets. We then assessed the ability of the coatings to protect the lipid droplets from aggregation when the pH (2.0-9.0), ionic strength (0 to 350 mM), or temperature (30-90°C) were altered. The properties of the primary, secondary, and tertiary emulsions were monitored by measuring the mean particle diameter (d32), electrical characteristics (ζ-potential), and microstructure of the lipid droplets. The electrical characteristics of the droplets could be modulated by controlling the number and type of layers used. The primary emulsion had the best resistance to varying environmental conditions, while the secondary emulsion had the worst, suggesting electrostatic deposition should only be used to obtain specific functionalities. Interestingly, PLL detached from the surfaces of the secondary emulsions at high salt concentrations due to electrostatic screening, which improved their salt stability. This phenomenon may be useful for some food applications, e.g., having cationic droplets during food storage, but anionic ones inside the human body. Thirdly, multilayer coatings were formed from saponins, polypeptides, and polysaccharides using medium chain triglyceride (MCT) lipid droplets as templates (pH 4.0). First, an emulsion containing negatively charged lipid droplets was created using quillaja saponin (QS) as an anionic emulsifier. Second, these anionic droplets were coated with a cationic polypeptide (poly-L-lysine, PLL) to form positively-charged droplets. Finally, these cationic droplets were coated with a negatively-charged polysaccharide, either pectin (PE) or κ-carrageenan (KC), to form anionic droplets. Overall, the 1-layer emulsions had the best resistance to salt, pH, and heat, indicating that quillaja saponins were effective emulsifiers. The 2-layer emulsions had better pH-stability than the 3-layer emulsions, which tended to strongly aggregate under acidic conditions. Conversely, the 3-layer emulsions had better salt-stability than the 2-layer emulsions, which tended to aggregate strongly even at low salt levels (50-100 mM NaCl). All the emulsions were relatively stable to heating (90oC, 30 min). Fourth, the kinetics of β-carotene degradation in multilayer nanoemulsions was measured. Primary emulsions were formed containing anionic quillaja saponin-coated MCT oil droplets loaded with β-carotene. Secondary emulsions were then formed by depositing cationic polypeptide poly-l-lysine (PLL) onto these anionic droplets. Tertiary emulsions were then formed by depositing anionic poly-glutamic acid (PGA), pectin (PE) or κ-carrageenan (KC) onto these cationic droplets. All the multilayer emulsions were prepared at pH 4.0 to ensure the biopolymers had opposite charges. The kinetics of β-carotene degradation in the different emulsions were then measured when they were incubated at 55°C. In addition, changes in the particle size and ζ-potential of the emulsions were measured using light scattering methods. The chemical stability of the encapsulated carotenoid was highly dependent on the nature the nature of the coating used. The secondary emulsions, which had cationic PLL as an external layer, gave the best protection against color fading, with a final yellowness (b*) of 82% after two weeks. Conversely, the tertiary emulsions, which had anionic polysaccharides or polypeptides as an external layer, gave the worst protection. For instance, when KC was used as the external layer the final yellowness was only 32% after two weeks. These results show that the stability of carotenoids can be improved by controlling the properties of multilayer coatings around oil droplets

Multi-Objective Optimization of a Vehicle Body by Combining Gradient-based Methods and Vehicle Concept Modelling

Abstract In the automotive field, size optimization procedures can be combined with concept modelling approaches, in order to design a vehicle Body-In-White (BIW) model with optimal static and dynamic performances already in the early design stages. However, this specific optimization problem, with hundreds of design variables, limited design space and often conflicting objectives, makes the choice of the appropriate optimization method really difficult. The aim of this paper is to show an industrial case study, where two different implementations of the classical gradient-based (GB) method are used in combination with a technique for vehicle body concept modelling to achieve a multi-objective BIW optimization of a passenger car

What Matters Most to Patients and Rheumatologists? A Discrete Choice Experiment in Rheumatoid Arthritis

Introduction: To determine patient and rheumatologist preferences for rheumatoid arthritis (RA) treatment attributes in Spain and to evaluate their attitude towards shared decision-making (SDM). Methods: Observational, descriptive, exploratory and cross-sectional study based on a discrete choice experiment (DCE). To identify the attributes and their levels, a literature review and two focus groups (patients [P] = 5; rheumatologists [R] = 4) were undertaken. Seven attributes with 2–4 levels were presented in eight scenarios. Attribute utility and relative importance (RI) were assessed using a conditional logit model. Patient preferences for SDM were assessed using an ad hoc questionnaire. Results: Ninety rheumatologists [52.2% women; mean years of experience 18.1 (SD: 9.0); seeing an average of 24.4 RA patients/week (SD: 15.3)] and 137 RA patients [mean age: 47.5 years (SD: 10.7); 84.0% women; mean time since diagnosis of RA: 14.2 years (SD: 11.8) and time in treatment: 13.2 years (SD: 11.2), mean HAQ score 1.2 (SD: 0.7)] participated in the study. In terms of RI, rheumatologists and RA patients viewed: time with optimal QoL: R: 23.41%/P: 35.05%; substantial symptom improvement: R: 13.15%/P: 3.62%; time to onset of treatment action: R: 16.24%/P: 13.56%; severe adverse events: R: 10.89%/P: 11.20%; mild adverse events: R: 4.16%/P: 0.91%; mode of administration: R: 25.23%/P: 25.00%; and added cost: R: 6.93%/P: 10.66%. Nearly 73% of RA patients were involved in treatment decision-making to a greater or lesser extent; however, 27.4% did not participate at all. Conclusion: Both for rheumatologists and patients, the top three decision-making drivers are time with optimal quality, treatment mode of administration and time to onset of action, although in different ranking order. Patients were willing to be more involved in the treatment decision-making process

Assessment of Copper Total Bioaccumulation and Genotoxicity in Boac River, Marinduque Island, Philippines Two Decades Post-Mining Disaster: Pseudodon sp. as Aquatic Fauna Indicator

In 1996, a mining drainage tunnel burst and released copper wastes into the Boac River—rendering it dead. Two decades after the disaster, the river is now used for aquaculture farming. This study assessed the total bioaccumulation of copper and its genotoxicity in the mussel Pseudodon sp. farmed in the river. A total of 30 Pseudodon sp. were collected randomly from the downstream tributaries of the river in September 2015. Total bioaccumulation in terms of total copper concentrations was determined by atomic absorption spectrometry and the genotoxicity by micronucleus cytome assay. The total copper concentrations were present in the soft tissues (Mean + Standard Error of the Mean [SEM] of 0.0550 + 0.0003 ppm). Genotoxic indicators of nuclear alterations showed the formation of micronuclei yielding the highest frequency (Mean + SEM of 10.257 + 0.793 per 1000 cells). Binucleated, nuclear buds, agranular, apoptotic, and necrotic nuclear anomalies were likewise evident. Total copper concentrations and the frequency of the hemocyte micronuclei occurrences showed a significant relationship (r=0.366; p = 0.047) while the other nuclear abnormalities were not significantly related to the total copper concentrations. Continuous biomonitoring of mining-affected areas is necessary to safeguard people’s health from the effects of mining wastes. Keywords: bioaccumulation · copper · energy use · genotoxicity · heavy metal · mining · nuclear abnormalitie

O gene do receptor GABA A- γ2 (GABRG2) no transtorno obsessivo-compulsivo

OBJECTIVE: The γ-aminobutyric acid type A (GABA A) system may be implicated in obsessive-compulsive disorder, based on its major role in modulation of anxiety and its function as the principal inhibitory neurotransmitter system in the cortex. In addition, glutamatergic/GABAergic mechanisms appear to play a role in the pathophysiology of obsessive-compulsive disorder, making the GABA A receptor-γ2 (GABργ2) gene a good candidate for susceptibility in this disorder. METHOD: 118 probands meeting DSM-IV criteria for primary obsessive-compulsive disorder and their available parents were recruited for participation in this study and informed consent was obtained. An NciI restriction site polymorphism in the second intron was genotyped and data was analyzed using the Transmission Disequilibrium Test. RESULTS: In total, 61 of the participating families were informative (i.e., with at least one heterozygous parent). No biases were observed in the transmission of either of the two alleles (χ2 = 0.016, 1 d.f., p = 0.898) to the affected probands in the total sample. CONCLUSION/DISCUSSION: While these results do not provide support for a major role for the GABA A receptor-γ2 in obsessive-compulsive disorder, further investigations of this gene in larger samples are warranted

Short and long term surface chemistry and wetting behaviour of stainless steel with 1D and 2D periodic structures induced by bursts of femtosecond laser pulses

We investigate the short and long term wettability of laser textured stainless steel samples in order to better understand the interplay between surface topography and chemistry. Very different 1D and 2D periodic as well as non-periodic surface patterns were produced by exploiting the extreme flexibility of a setup consisting of five rotating birefringent crystals, which allows generating bursts of up to 32 femtosecond laser pulses with fixed intra-burst delay of 1.5 ps. The change of the surface morphology as a function of the pulse splitting, the burst polarization state and the fluence was systematically studied. The surface topography was characterized by SEM and AFM microscopy. The laser textured samples exhibited, initially, superhydrophilic behaviour which, during exposure to ambient air, turned into superhydrophobic with an exponential growth of the static contact angle. The dynamic contact angle measurements revealed a water adhesive character which was explained by XPS analyses of the surfaces that showed an increase of hydrocarbons and more oxidized metal species with the aging. The characteristic water adhesiveness and superhydrophobicity of laser textured surfaces can be exploited for no loss droplet reversible transportation or harvesting

Analytical and clinical evaluation of DiaSorin Liaison® Calprotectin fecal assay adapted for serum samples

Background Calprotectin is a calcium-binding protein that can be measured in serum, plasma, and feces. Increased serum and plasma calprotectin concentrations have been found in chronic inflammatory rheumatic disorders. An analytical and clinical evaluation of the DiaSorin Liaison (R) fecal Calprotectin assay using LIAISON (R) XL was performed. Methods The protocol included an analytical and clinical evaluation in which imprecision, the linearity of dilution, differences between serum and plasma samples and method comparison with CalproLab (TM) ELISA kit were assessed. Serum calprotectin concentrations in active (n = 26) and remission (n = 23) rheumatoid arthritis (RA) patients were compared. Results The intra-day and inter-day analytical imprecision CVs ranged from 2.9% to 4.0% and 2.7% to 10.4%, respectively. Correlation between measured and expected values was high (R > 0.99), indicating good linearity. The Wilcoxon signed-rank test showed that serum and plasma matched samples presented statistically significant differences (p < 0.001) being the highest concentrations of calprotectin observed in serum samples. Deming regression equation was as follows: Diasorin calprotectin (mu g/ml) = -0.32 (95% CI: -0.65 - -0.05) +1.58 (95% CI: 1.42-1.79).* Calprolab calprotectin (mu g/ml). Significantly higher serum calprotectin levels were found in RA patients with active disease when compared to patients with low disease activity or in clinical remission (mean +/- SD) [(3.35 mu g/ml +/- 1.55) vs. (1.63 mu g/ml +/- 0.52), p < 0.001] and these levels correlated well with all disease activity indices. Conclusions The DiaSorin Liaison (R) fecal Calprotectin assay adapted for serum samples showed adequate technical performances and the clinical performances were similar to other assays

Buenas prácticas agrícolas en la frutihorticultura del partido de General Pueyrredón

La presente propuesta tiene por objetivo analizar la incidencia que tiene, en la producción frutihortícola del partido de General Pueyrredon, la incorporación de Buenas Prácticas Agrícolas (BPA) y la implementación de certificaciones que avalan las demandas actuales ligadas a la calidad de estos productos. Se indaga acerca de las características de los agentes agrarios que han incorporado estas prácticas de diferenciación, se propone conocer sus motivaciones y examinar los alcances de las instituciones y regulaciones locales y extralocales en estos procesos, así como analizar si estos dispositivos pueden constituir una herramienta de inclusión y oportunidad de insertarse en nuevos y exigentes mercados o una forma de concentrar el grupo de oferentes, configurando un mecanismo de exclusión. Los resultados preliminares muestran escasas modalidades de diferenciación en cuanto a BPA en la frutihorticultura, asociadas a protocolos y certificaciones, implementadas solo por productores empresariales que participan en la comercialización externa o son proveedores de alguna cadena de supermercados. Además, se observa la incorporación de parámetros de calidad generados localmente por actores tales como asociaciones de productores e instituciones técnicas. Estos procesos recientes vinculados a la introducción del concepto de calidad y su puesta en práctica implican tensiones y transformaciones en las relaciones socio-productivas, acentuadas por la obligatoriedad de aplicar BPA en el sector, a partir de los años 2020 y 2021. Se adopta una estrategia metodológica fundamentalmente cualitativa, con entrevistas semiestructuradas a distintos informantes calificados. Se complementa con el análisis de documentos bibliográficos, normativas sobre BPA, informes de certificadoras, así como otras fuentes de información relevantes.Evento realizado junto con el VII Congreso Nacional de Geografía de Universidades PúblicasFacultad de Humanidades y Ciencias de la Educació

Development and Validation of “Hazard O’Clock”: A Home Hazard and Disaster Awareness Game

The Philippines is the fourth most disaster-prone country in the world due to its location in the Pacific Ring of Fire and Pacific Typhoon Belt. When it comes to these disasters, children below the age of 18 are considered to be among the most vulnerable. This study aimed to develop a mobile game about Disaster Risk Reduction and Management (DRRM) in the home setting that can be used as a teaching aid for children. The information integrated into the game was from different resources made by various government agencies. The Analysis, Design, Development, Implementation, and Evaluation (ADDIE) model was used in the development of the game, and game development educators and STEM educators evaluated it. Using a 5-point Likert scale survey, the game’s quality and appropriateness were evaluated for the following categories: Instructional Content, Functional Suitability, Performance Efficiency, and Usability. For each category, the mean score ratings were 4.43, 4.43, 4.80, and 4.60 respectively. Overall, the game received a rating of 4.52 indicating that it is Very Appropriate for its purpose. The research findings have shown that the game, Hazard O’Clock, could be used as a teaching aid for DRRM