On the one-loop effective potential in the higher-derivative four-dimensional chiral superfield theory with a nonconventional kinetic term

We explicitly calculate the one-loop effective potential for a higher-derivative four-dimensional chiral superfield theory with a nonconventional kinetic term. We consider the cases of minimal and nonminimal general Lagrangians. In particular, we find that in the minimal case the divergent part of the one-loop effective potential vanishes by reason of the chirality.Comment: 9 page

Desenvolvimento de Cryptolaemus montrouzieri (Coleoptera: Coccinellidae) alimentado com ovos de Ceratitis capitata (Diptera: Tephritidae).

O objetivo deste trabalho foi avaliar o desenvolvimento de C. montrouzieri criado em uma dieta composta apenas por ovos de C. capitata para possibilitar um método de criação desta joaninha com baixo custo, de modo a obter este inimigo natural em quantidades suficientes para utilização em programas de manejo integrado de pragas

Nanocellulose bio-based composites for food packaging

The food industry is increasingly demanding advanced and eco-friendly sustainable packaging materials with improved physical, mechanical and barrier properties. The currently used materials are synthetic and non-degradable, therefore raising environmental concerns. Consequently, research efforts have been made in recent years towards the development of bio-based sustainable packaging materials. In this review, the potential of nanocelluloses as nanofillers or as coatings for the development of bio-based nanocomposites is discussed, namely: (i) the physico-chemical interaction of nanocellulose with the adjacent polymeric phase, (ii) the effect of nanocellulose modification/functionalization on the final properties of the composites, (iii) the production methods for such composites, and (iv) the effect of nanocellulose on the overall migration, toxicity, and the potential risk to human health. Lastly, the technology readiness level of nanocellulose and nanocellulose based composites for the market of food packaging is discussed.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.” The authors also acknowledge the financial support of the FCT (ESF) through the grant given to Francisco A.G.S. Silva (SFRH/BD/146375/2019).info:eu-repo/semantics/publishedVersio

Regenerated bacterial cellulose fibres

The global shortage of cotton for textile production, forces the exploitation of forests´ lignocellulosic biomass to produce man-made cellulosic fibres (MMCF). This has a considerable environmental impact, pressing the textile industry to search for new sustainable materials and to the development of sustainable recycling processes. Bacterial cellulose (BC), an exopolysaccharide produced by fermentation, could represent such an alternative. In particular, we tested the possibility of improving the mechanical properties of cellulose filaments with a low degree of polymerization (DP) by combining them with high DP from BC, so far exploited to little extent in the textile field. In this work, BC with different degrees of polymerization (DPcuaxam) (BCneat: 927; BCdep:634 and BCblend: 814) were dissolved in N-methylmorpholine-N-oxide (NMMO) and their spinnability was studied. The rheological behaviour of the dopes was assessed and all were found to be spinnable, at suitable concentrations (BCneat:9.0%; BCdep:12.2%; BCblend:10.5%). A continuous spinning was obtained and the resulting filaments offered similar mechanical performance to those of Lyocell. Further, the blending of BC pulps with different DPs (BCblend, obtained by combining BCneat and BCdep) allowed the production of fibres with higher stiffness (breaking tenacity 56.4 CN.tex1) and lower elongation (8.29%), as compared to samples with more homogeneous size distribution (neat BC and depolymerized BC).info:eu-repo/semantics/publishedVersio

A Critical Approach to the Theoretical Corpus of the Commercial Associations

Texto dispoñible en galego e españolEste artigo é unha primeira aproximación ao marco teórico a partir do cal se construíron os esforzos de integración económica rexional e o seu obxectivo é estudar a súa utilidade para analizar os procesos de integración. A evolución dos enfoques teóricos aquí discutidos xustifican a existencia dunha perspectiva que permite formular a hipótese de que os procesos de integración económica entre economías asimétricas non necesariamente elevan o benestar dos participantes nin do mundo no seu conxuntoEste artículo es una primera aproximación al marco teórico a partir del cual se han construido los esfuerzos de integración económica regional y su objetivo es estudiar su utilidad para analizar los procesos de integración. La evolución de los enfoques teóricos aquí discutidos justifica la existencia de una perspectiva que permite formular la hipótesis de que los procesos de integración económica entre economías asimétricas no necesariamente elevan el bienestar de los participantes ni del mundo en su conjuntoThis article is a first approach to a theoretical frame from which different efforts of regional economic integration have been constructed, and its interest is to study its utility when analyzing integration processes. The evolution of the theoretical basis hereby discussed grants justification to the existence of a perspective that allows the formulation of an hypotheses that states that the economic integration processes among assymetric economies do not necessarily raise the welfare of the participants, particularly, and of the world, in a general viewS

Principais espécies arbóreas hospedeiras de cipó-titica (Heteropsis flexuosa) em Rondônia.

O objetivo deste trabalho foi identificar as principais espécies arbóreas hospedeiras de cipó titica (Heteropsis flexuosa) em Floresta Ombrófila Aberta como base para o manejo e conservação da espécie.bitstream/CPAF-RO-2009-09/12383/1/ct96_cipo-titica.pd

Bacterial cellulose as a novel stabilizer and texturizer for cosmetic and food applications

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Bacterial nanocellulose (BNC) is a sophisticated material produced biotechnologically by different microorganisms, but most efficiently by acetic acid bacteria from the genera Gluconacetobacter. While chemically identical to plant cellulose, BNC is chemically pure. Each BNC nanofiber is a bundle of cellulose nanofibrils. Due to their nano-size, these aggregates of extended cellulose chains have a rather large surface area. The unique properties of BNC account for an extraordinary physico-chemical and mechanical behaviour. For industrial applications, hydrocolloidal microcrystalline cellulose from vegetable sources is widely used to regulate the texture, rheology, stability and organoleptic properties of the formulations [1]. Several studies are being carried out to investigate the technological role of BNC. Preliminary results already showed that BNC is technically superior to these vegetable celluloses, and can outperform plant celluloses in several applications within the food industry. As a novel hydrocolloid, BNC presents important features such as the stabilization of heterogeneous systems (air-liquid, solid-liquid and liquidliquid): it is able to stabilize aerogels, increasing the incorporation of air in the liquid matrix (overrun), so it can be used as an additive in ice cream, smoothies and whipped cream; it can stabilize solid particles in a liquid matrix (e.g. cocoa particles in chocolate milk); BNC also stabilizes of oil-in-water emulsions, in spoonable and pourable dressings, without the need to add any other emulsifying agents. [...]info:eu-repo/semantics/publishedVersio

Development of bacterial cellulose composites for food packaging and textiles

Most of all petroleum-based materials are used for a short period of time but then take centuries to degrade. Food packaging and textile are examples of industries that are truly dependent of synthetic materials. Therefore, there is an increasing interest on seeking alternatives to these materials. Plant nanocellulose (PNC) has been actively studied, yet the high demand may arise environmental issues such deforestation and wood processing. An alternative source is bacterial cellulose (BC), produced by bacteria of the genus Komagataeibacter, through fermentation. BC has a great potential due to great mechanical performance, despite some drawbacks such high water affinity (for food packaging) and high molecular weight (for textiles). Different approaches were used with the attempt to reduce water vapor permeability and functionalize BC based composite for Food packaging. For textiles, highly performing fibres were developed after using adapted Lyocell and Ioncell technologies.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, BIOPROTECT - Development of Biodegradable Packaging Material with Active Properties for Food Preservation POCI-01-0247-FEDER-069858, COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional DevelopmentFund under the scope of Norte2020 - Programa Operacional Regional do Norte.” The authors also acknowledge the financial support of the FCT (ESF) through the grant given to Francisco A.G.S. Silva (SFRH/BD/146375/2019). The authors also thank all the support given by the Thuringian Institute for Textile and Plastics Research (TITK) and the department of Bioproducts and Biosystems at Aalto University. The authors also thank the support of Aquitex - Acabamentos Químicos Têxteis, S.A.info:eu-repo/semantics/publishedVersio

Optimization of bacterial nanocellulose fermentation using lignocellulosic residues and development of novel BNC-starch composites

In papermaking industry, significant fraction of fibres that cannot be re-utilized are wasted, which raise economic and environmental concerns[1]. On the other hand, development of renewable polymeric materials became a priority for the sustainability of several industries. Bacterial nanocellulose (BNC), a biopolymer extruded by Gluconacetobacter xylinus as a 3D nanofibrillar network, provide interesting properties as high porosity, high water retention, biocompatibility, non-toxicity and biodegradability [2]. These properties have sustained promising applications in the biomedical field, papermaking, composites and foods. However, large-scale BNC production remains a challenge, due to ineffective fermentation systems and high operating costs [2-3]. Therefore, the production of BNC through lignocellulosic residues has been studied. Recycled-paper-sludge (RPS) composed of small fibres with 40% of carbohydrates were hydrolysed and used as a carbon source in culture media formulation. Then, a Response Surface Methodology (RSM) optimization with RPS was assessed in order to maximize BNC production, through static fermentation with K. hansenii ATCC 53582. Overall, the results suggest that RPS had potential to be an alternative carbon source for BNC production with a maximum BNC yield of 5 g/L. BNC produced as described above was then used for the development of novel green thermoplastic nanocomposites, combined with starch. When mixed with water and glycerol (with heat and shear), starch undergoes spontaneous destructuring, forming thermoplastic starch (TPS). In particular to food packaging applications, BNC has remained unexploited in spite of being considered to have enormous potential [4-5]. In this work, two approaches for composite production were assessed. Firstly, BNC 3D membrane was filled with biodegradable bio-based thermoplastic starch (TPS), where the production was achieved in a two-step process: impregnation of TPS in the BNC membrane, followed by drying. Different thicknesses of BNC membrane were studied (1-5 mm) as two impregnation time (24h;72h). The second approach consisted on the use of glycerol-TPS as matrix, where different concentrations (0.05 -0.5% w/v) of cellulose (Plant (PC) and BNC) was added. TPS-BNC and TPS-PC films were prepared by solution casting method. All nanocomposites manufactured were then characterized in terms of mechanical properties, morphology and permeability to water vapor (WVT). Overall, enhanced mechanical and barrier properties were obtained with BNC-TPS composites. In comparison to TPS-BNC and TPS-PC films, higher young modulus and tensile strength was obtained with the BNC-TPS composites. Being longer andinfo:eu-repo/semantics/publishedVersio