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Paper is one of the most promising materials for food packaging and wrapping due to its low environmental impact, but surface treatments are often needed to improve its performance, e.g., the resistance to fats and oils. In this context, this research is focused on the formulation of a new paper bio-coating. Paper was coated with liquids containing poly(hexano-6-lactone) (PCL), glycerol and variable percentages of starch (5-10% w/w PCL dry weight), agar-agar (0-1.5% w/w PCL dry weight), and polyethylene glycol (PEG) (5% or 15% w/w PCL dry weight) to improve coating uniformity and diffusion. A design of experiments approach was implemented to find statistically reliable results in terms of the best coating formulation. Coated paper was characterized through mechanical and physical properties. Results showed that agar content (1.5% w/w PCL dry weight) has a beneficial effect on increasing the resistance to oil. Furthermore, the best coating composition has been calculated, and it is 10% w/w PCL dry weight of starch, 1.5% w/w PCL dry weight of agar, and 15% w/w PCL dry weight of PEG.
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In the present work, a statistical optimization of a sustainable coating for core-shell NPK (Nitrogen-Phosphorus-Potassium) fertilizers was investigated. The environmental green coating was enriched in nitrogen using a biomass and renewable source, namely the nitrogen rich fraction of black soldier fly larvae (BSFL) (Hermetia Illucens, Diptera: Stratiomyidae) reared on vegetable waste. A rational approach was proposed with the aim of calculating the best formulation of the coating, considering both its manufacturing behavior, such as adhesion to the core, and its physical properties, such as homogeneity or plasticity. From a circular economy perspective, together with the nitrogen-rich fraction from BSFL (from 51 to 90 wt.%), water and glycerol were considered for the coating formulation in different proportion: from 10 to 32 wt.% and from 0 to 17 wt.% respectively. The Design of Experiments technique was implemented to limit the total number of tests for the coating formulation (18 tests). ANOVA was employed, with the aim of obtaining mathematical models to derive a better precise and objective formulation. The results show that the use of glycerol can be avoided, as well as only a limited amount of water (11 wt.%) is necessary to obtain an optimized coating formulation, thereafter, satisfying the more relevant technological and physical properties for the coating manufacturing.
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Dípteros , Fertilizantes , Animales , Larva , Nitrógeno , Glicerol , AguaRESUMEN
The building sector is responsible for a third of the global energy consumption and a quarter of greenhouse gas emissions. Phase change materials (PCMs) have shown high potential for latent thermal energy storage (LTES) through their integration in building materials, with the aim of enhancing the efficient use of energy. Although research on PCMs began decades ago, this technology is still far from being widespread. This work analyses the main contributions to the employment of PCMs in the building sector, to better understand the motivations behind the restricted employment of PCM-based LTES technologies. The main research and review studies are critically discussed, focusing on: strategies used to regulate indoor thermal conditions, the variation of mechanical properties in PCMs-based mortars and cements, and applications with ground-coupled heat pumps. The employment of materials obtained from wastes and natural sources was also taken in account as a possible key to developing composite materials with good performance and sustainability at the same time. As a result, the integration of PCMs in LTES is still in its early stages, but reveals high potential for employment in the building sector, thanks to the continuous design improvement and optimization driven by high-performance materials and a new way of coupling with tailored envelopes.
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Insects are becoming increasingly relevant as protein sources in food and feed. The Black Soldier Fly (BSF) is one of the most utilized, thanks to its ability to live on many leftovers. Vegetable processing industries produce huge amounts of by-products, and it is important to efficiently rear BSF on different substrates to assure an economical advantage in bioconversion and to overcome the seasonality of some leftovers. This work evaluated how different substrates affect the protein and amino acid content of BSF. BSF prepupae reared on different substrates showed total protein content varying between 35% and 49% on dry matter. Significant lower protein contents were detected in BSF grown on fruit by-products, while higher contents were observed when autumnal leftovers were employed. BSF protein content was mainly correlated to fibre and protein content in the diet. Among amino acids, lysine, valine and leucine were most affected by the diet. Essential amino acids satisfied the Food and Agricultural Organization (FAO) requirements for human nutrition, except for lysine in few cases. BSF could be a flexible tool to bio-convert a wide range of vegetable by-products of different seasonality in a high-quality protein-rich biomass, even if significant differences in the protein fraction were observed according to the rearing substrate.
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In this study, an organic nitrogen-based coating was developed based on black soldier fly (BSF) prepupae reared on poultry dejections and deposited on ceramic lightweight aggregates (LWAs), containing phosphorous (P) and potassium (K) from agroresidues, leading to a complete nitrogen, phosphorus, and potassium (NPK) fertilizer. To obtain a resistant coating with good adhesion to LWAs, different plasticizing agents were tested (e.g., glycerol, cellulose, and polyethylene glycol). The coating formulation was optimized through a design-of-experiment (DoE) approach to correlate the effect of each mixture component on the coating's performance. BSF biomass was characterized through chemical and thermal routes, as well as the final coated LWAs, confirming their general agreement to fertilizer's requirements. Release tests in static conditions highlighted the barrier action of the coating, preventing uncontrolled release of potassium and phosphorus contained in the LWAs as well as the release of nitrogen after 21 days (near to 20%). Germination and growth tests indicated a valuable increase of the growth index, whereas the germination process is limited by the coating barrier effect. This work proposes a new product in the field of slow-release fertilizers designed by rational methodologies and innovative materials based on waste valorization, fully in agreement with a circular economy perspective.
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Most of the leftovers from agricultural productions and industrial processing of vegetables are currently discarded as waste, augmenting production costs and environmental impacts. Black soldier flies (BSF) are non-pest insects that can grow on various types of organic materials. The larvae initially act as fast and efficient bioconverters, before being further valorized as biomass rich in proteins, fats and chitin. The aim of the present study was to exploit the potential of BSF prepupae reared on vegetable leftovers with high seasonality, and to obtain compounds with high added value and further industrial and agronomic uses such as food/feed, soil improver or fuel. The optimization of BSF rearing substrates based on different leftovers combinations was performed through a Mixture Design approach. Initially, a database was built detailing the availability, seasonality and nutrient composition of the vegetable by-products. According to the seasonal availability of the agri-food leftovers, three main groups were identified: annual, summer and autumn mixtures, in order to promote the exploitation of the highest quantity of leftovers. This approach allowed the obtainment of statistically reliable correlations (R2 > 0.75) between the employed leftovers and the content of lipid and nitrogen compounds (protein and chitin) of the BSF prepupae. In particular, a mixture of vegetable leftovers available in autumn that included legume (25 wt%), cereal (20 wt%) and vegetable (25 wt%) wastes proved to be the best combination in terms of insect growth (-25% development time compared to the control group) and nutritional composition. The chemical composition of the insect biomass allowed the identification of potential applications with high added value, such as food ingredients (protein and fats) or nutraceuticals (chitin). The identification of the optimal parameters to ensure the greatest possible efficiency would promote the scale-up of BSF rearing to an industrial level.
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Simuliidae , Animales , Biomasa , Larva , Estaciones del Año , VerdurasRESUMEN
BACKGROUND: Vaccination strategies against bacterial meningitis vary across countries. In the United States, a single dose of quadrivalent meningococcal conjugate vaccine (MenACWY) is recommended at 11-12â¯years of age, with a booster dose approximately 5â¯years later. We assessed immune responses to a booster dose of MenACWY-CRM vaccine after priming with MenACWY-CRM or MenACWY-D vaccines in adolescents and adults. METHODS: In this phase IIIb, multicenter, open-label study, healthy 15-55-year-olds, who received MenACWY-CRM (Nâ¯=â¯301) or MenACWY-D (Nâ¯=â¯300) 4-6â¯years earlier or were meningococcal vaccine-naïve (Nâ¯=â¯100), received one MenACWY-CRM vaccine dose. Immunogenicity was evaluated pre-vaccination, 3 or 5â¯days post-vaccination (sampling subgroups), and 28â¯days post-vaccination by serum bactericidal activity assay using human complement (hSBA). After vaccination, participants were monitored for 7â¯days for reactogenicity, 29â¯days for unsolicited adverse events (AEs), and 181â¯days for serious AEs and medically-attended AEs. RESULTS: Sufficiency of the immune response to a MenACWY-CRM booster dose was demonstrated; the lower limit of the 1-sided 97.5% confidence interval for percentages of participants with hSBA seroresponse at 28â¯days post-vaccination was >75% for each serogroup in those primed with either the MenACWY-CRM or MenACWY-D vaccine. Seroresponse was observed in ≥93.24% of primed participants and ≥35.87% of naïve participants 28â¯days post-vaccination. At 5â¯days post-booster, among primed participants, hSBA titers ≥1:8 were achieved in ≥47.14% of participants for MenA and in ≥85.52% of participants for MenC, MenW and MenY, and 3.25- to 8.59-fold increases in hSBA geometric mean titers against each vaccine serogroup were observed. No safety concerns were raised throughout the 6-month follow-up period. CONCLUSIONS: A booster dose of the MenACWY-CRM vaccine induced a robust and rapid anamnestic response in adolescents and adults, irrespectively of either MenACWY-CRM or MenACWY-D vaccine administered 4-6â¯years earlier, with an acceptable clinical safety profile. ClinicalTrials.gov registration: NCT02986854.
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Inmunogenicidad Vacunal/inmunología , Meningitis Meningocócica/prevención & control , Vacunas Meningococicas/inmunología , Neisseria meningitidis/inmunología , Adolescente , Adulto , Anticuerpos Antibacterianos/sangre , Proteínas del Sistema Complemento/inmunología , Femenino , Humanos , Inmunización Secundaria , Memoria Inmunológica/inmunología , Masculino , Meningitis Meningocócica/inmunología , Persona de Mediana Edad , Vacunación , Adulto JovenRESUMEN
PURPOSE: Results from a post-marketing study to generate evidence on 1-year antibody persistence and safety following vaccination of infants from South Korea with the quadrivalent meningococcal conjugate vaccine MenACWY-CRM. MATERIALS AND METHODS: In this phase IV, open-label, multi-center study (NCT02446691), 128 infants received MenACWY-CRM at ages 2, 4, 6, and 12 months. One-year antibody persistence following the full vaccination course was evaluated (primary objective) for the four meningococcal serogroups (Men) by serum bactericidal activity assay using human or rabbit complement (hSBA/rSBA). Immune responses at 1-month post-vaccination and safety were also assessed. RESULTS: The percentage of children with hSBA titers ≥8 ranged between 94% (MenA) and 100% (MenY/W) 1-month post-vaccination, and from 39% (MenA) to 89% (MenY) 1-year post-vaccination. At least 99% and 92% of children had rSBA titers ≥8 and ≥128 against each meningococcal serogroup, 1-month post-vaccination. One-year post-vaccination, the percentage of children with rSBA titers ≥8 and ≥128 ranged from 54% (MenC) to 99% (MenA) and from 30% (MenC) to 98% (MenA). Geometric mean titers declined from 1-month to 1-year post-vaccination, when they varied between 6.8 (MenA) and 53.6 (MenW) by hSBA and between 17.2 (MenC) and 2,269.5 (MenA) by rSBA. At least one solicited and unsolicited adverse event was reported for 79% and 66% of children. Of 36 serious adverse events reported, none were vaccination-related. CONCLUSION: Antibody persistence (hSBA/rSBA titers ≥8) was determined in 39%-99% of children 1 year after a 4-dose MenACWY-CRM series during infancy, with an acceptable clinical safety profile.
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BACKGROUND: The quadrivalent meningococcal conjugate vaccine MenACWY-CRM has been shown to be immunogenic and well-tolerated in infants and toddlers. We evaluated antibody persistence for up to 4â¯years after vaccination with MenACWY-CRM in the first years of life and response to a booster dose administered at 60â¯months of age. METHODS: This was phase 3b, open-label, multicenter extension trial (NCT01148017). We assessed by hSBA and rSBA the persistence of antibody responses to serogroups ACWY in 203 healthy 60-month-olds receiving 4 doses of MenACWY-CRM during infancy (ACWY-4 group), or 2 doses at 12/13 and 15â¯months or 1 dose at 18â¯months of age (ACWY-2 group). We administered a MenACWY-CRM dose to 224 primed and 45 naïve 60-month-olds and evaluated safety and antibody response 1â¯month later. RESULTS: Antibody persistence measured by both assays was higher in primed than naïve 60-month-olds. The percentages of primed children with hSBA titers ≥8 was low for serogroup A (6-25%) and moderate for serogroups C (27-43%), Y (69-74%) and W (56-69%). For all serogroups, hSBA antibody geometric mean titers (GMTs) tended to be higher in the ACWY-2 than the ACWY-4 group. Post-booster/single dose, ≥96% of primed and ≥73% of naïve children had hSBA titers ≥8 against each serogroup, and hSBA GMTs were higher in primed children. The booster dose was well-tolerated and no safety concern was identified. We further assessed persistence using rSBA across different age groups and detected no overall correlation between rSBA and hSBA titers. CONCLUSIONS: Primary vaccination of infants/toddlers with MenACWY-CRM resulted in moderate antibody persistence against serogroups C, W and Y for up to 4â¯years after the last priming dose. Regardless of priming schedule, a MenACWY-CRM booster dose at 60â¯months of age induced a robust immune response against all serogroups and was well-tolerated in all children.
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Anticuerpos Antibacterianos/inmunología , Vacunas Meningococicas/inmunología , Actividad Bactericida de la Sangre/inmunología , Preescolar , Femenino , Humanos , Inmunización Secundaria/métodos , Masculino , Infecciones Meningocócicas/inmunología , Neisseria meningitidis/inmunología , Serogrupo , Factores de Tiempo , Vacunación/métodos , Vacunas Conjugadas/inmunologíaRESUMEN
In this study proteins extracted from prepupae of Hermetia illucens, also known as black soldier fly, are investigated as promising base for a new type of bioplastics for agricultural purposes. Design of experiments techniques are employed to perform a rational study on the effects of different combination of glycerol as plasticizer, citric acid as cross-linking agent and distilled water as solvent on the capability of proteins to form a free-standing film through casting technique, keeping as fixed the quantity of proteins. Glycerol shows interesting properties as plasticizer contributing to the formation of homogenous and free-standing film. Moreover, mechanical and thermal characterizations are performed to estimate the effect of increasing amounts of proteins on the final properties and thickness of the specimens. Proteins derived from H. illucens can be successfully employed as base for bioplastics to be employed for agricultural purposes.
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Plásticos Biodegradables , Dípteros/química , Proteínas de Insectos/química , Membranas Artificiales , Animales , Plásticos Biodegradables/síntesis química , Plásticos Biodegradables/química , Pupa/químicaRESUMEN
BACKGROUND: Neisseria meningitidis serogroups A, B, C, W and Y cause most meningococcal disease worldwide. An investigational MenABCWY vaccine combining serogroup B antigens and a meningococcal ACWY CRM197-glycoconjugate vaccine (MenACWY-CRM) could provide protection against all 5 serogroups. Complement mediated bactericidal activity induced by MenABCWY was tested against a panel of 110 randomly-selected serogroup B strains causing invasive disease in the US to evaluate the vaccine's breadth of coverage (BoC). METHODS: We conducted this observer-blind study (NCT02140762) and its extension (NCT02285777) in 8 centers in the US. Adolescents aged 10-18â¯years were randomized (1:1) to receive either 3 MenABCWY doses (MenABCWY group), on a 0, 2, 6-month (M) schedule or a single MenACWY-CRM dose at M2 and placebo at 0,6-M (Control group). MenABCWY BoC was calculated as (1â¯-â¯relative risk)â¯×â¯100 (relative riskâ¯=â¯ratio between the percentage of samples seronegative at 1:4 dilution against the selected strains in the MenABCWY vs Control group). BoC was determined at 1â¯M and 4â¯M after 2 and 3 doses, using an endogenous complement serum bactericidal assay. Immunogenicity and safety were assessed. RESULTS: 301 and 189 adolescents were vaccinated in the parent and extension study, respectively. At 1â¯M post-vaccination, the BoC of MenABCWY across the 110 serogroup B strains was 67% (95%CI: 65-69) after 2 doses and 71% (95%CI: 69-73) after 3 doses. BoC decreased to 44% (95%CI: 41-47) and 51% (95%CI: 48-55) at 4â¯M after 2 and 3 MenABCWY doses, respectively. Robust immune responses to antigen-specific test strains for each serogroup were observed at all timepoints in the MenABCWY group. No reactogenicity or safety concerns arose during the study. CONCLUSION: Two or 3 doses of MenABCWY showed similar BoC against the panel of invasive US serogroup B isolates and comparable immunogenicity against the antigen-specific test strains, with no safety concerns identified.