Modelling Taylor Rule Uncertainty

In recent years, one has witnessed a widespread attention on the way monetary policy is conducted and in particular on the role of the so-called monetary policy rules. The conventional approach in the literature consists in estimating reaction functions for a monetary authority (the Federal Reserve, in most cases) in which a nominal interest rate, directly or indirectly controlled by that monetary authority, is adjusted in response to deviations of inflation (current or expected) from target and of output from potential. These reaction functions, usually called Taylor rules, following John Taylor's seminal paper published in 1993, match a number of normative principles set forth in the literature for optimal monetary policy. This provides a good reason for the growing prominence of indications given by Taylor rule estimations in debates about current and prospective monetary policy stance. However, they are usually presented as point estimates for the interest rate, giving a sense of accuracy that can be misleading. Typically, no emphasis is placed on the risks of those estimates and, at least to a certain extent, the reader is encouraged to concentrate on an apparently precise central projection, ignoring the wide degree of uncertainty and operational difficulties surrounding the estimates. As in any forecasting exercise, there is uncertainty regarding both the estimated parameters and the way the explanatory variables evolve during the forecasting horizon. Our work presents a methodology to estimate a probability density function for the interest rate resulting from the application of a Taylor rule (the Taylor interest rate) which acknowledges that not only the explanatory variables but also the parameters of the rule are random variables.

Dynamics of antiproton plasma in a time-dependent harmonic trap

An antiproton plasma confined in a quasi-1D device is described in terms of a self-consistent fluid formulation using a variational approach. Unlike previous treatments, the use of the time-dependent variational method allows to retain the thermal and Coulomb effects. A certain Ansatz is proposed for the number density and fluid velocity fields, which reduces the problem essentially to ordinary nonlinear differential equations. In adiabatic cooling, the frequency of the trap potential is slowly decreased. An adiabatic equation of state is assumed for closure. The numerical simulation of the nonlinear dynamics is performed, for realistic parameters

Using choreographies to support the gamification process on the development of an application to reduce electricity costs

Building automation systems contribute to reduce electricity costs by managing distributed energy resources in an efficient way. However, a large share of consumption cannot be optimized through automation alone, since it mainly depends on human interactions. Gamification can be used as one form of changing users’ behaviours [1], but its implementation does require assumptions on the behaviour patterns that need to be identified, encouraged, or discouraged. To tackle this problem, we propose a framework that joins building automation solutions with gamification techniques to enable behavioural demand response.info:eu-repo/semantics/publishedVersio

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 Specialized Long-Term Distribution System Expansion Planning Method With the Integration of Distributed Energy Resources

The electrical distribution system (EDS) has undergone major changes in the last decade due to the increasing integration of distributed generation (DG), particularly renewable energy DG. Since renewable energy resources have uncertain generation, energy storage systems (ESSs) in the EDS can reduce the impact of those uncertainties. Besides, electric vehicles (EVs) have been increasing in recent years leveraged by environmental concerns, bringing new challenges to the operation and planning of the EDS. In this context, new approaches for the distribution system expansion planning (DSEP) problem should consider the distributed energy resources (DG units, ESSs, and EVs) and address environmental impacts. This paper proposes a mixed-integer linear programming model for the DSEP problem considering DG units, ESSs, and EV charging stations, thus incorporating the environmental impact and uncertainties associated with demand (conventional and EVs) and renewable generation. In contrast to other approaches, the proposed model includes the simultaneous optimization of investments in substations, circuits, and distributed energy resources, including environmental aspects (CO 2 emissions). The optimization method was developed in the modeling language AMPL and solved via CPLEX. Tests carried out with a 24-node system illustrate its effectiveness as a valuable tool that can assist EDS planners in the integration of distributed energy resources.This work was supported in part by the Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES), in the scope of the Program CAPES-PrInt, under Grant 88887.310463/2018-00 and Grant 88887.570741/2020-00; in part by the Brazilian National Council for Scientific and Technological Development (CNPq) under Grant 313047/2017-0; in part by the São Paulo Research Foundation (FAPESP) through CENERGETIC Research Project under Grant 2015/21972-6, Grant 2017/02831-8, Grant 2018/23617-7, Grant 2018/20990-9, and Grant 2018/08008-4; in part by the Fundo Europeu de Desenvolvimento Regional (FEDER) Funds through the Operational Program for Competitiveness and Internationalization (COMPETE2020) under Project POCI-01-0145-FEDER-028983; and in part by the National Funds through the Fundação para a Ciência e Tecnologia (FCT) Portuguese Foundation for Science and Technology under Project PTDC/EEI-EEE/28983/2017 (CENERGETIC), Project CEECIND/02814/2017, and Project UIDB/000760/2020.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

Development of layered BNC composites for Food Packaging

The food industry is increasingly demanding advanced and sustainable packaging materials with improved physical, mechanical and barrier properties. The currently used materials are synthetic and non-degradable, which raises environmental concerns. Research efforts have been made in recent years towards the development of bio-based sustainable packaging materials. One of those is nanocellulose, which have a potential to be used as matrix, as nanofillers or as coatings for composites [1]. A promising material is bacterial nanocellulose (BNC), a biopolymer extruded by Komagaebacter xylinus as a 3D nanofibrillar network. BNC offers interesting properties such as high porosity, biocompatibility, non-toxicity and biodegradability [2]. From a food packaging perspective, BNC has a great potential due to the great mechanical performance. However, the high water affinity of BNC is ta major obstacle for food packaging applications [3]. Therefore, the first task was to develop a layered biodegradable composite based on a plasticized BNC (either with glycerol or polyethylene glycol) and poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), as an attempt to improve the water vapour permeability. The PHBV coating on plasticized BNC reduced significantly the water vapour permeability (from 0.990 to 0.032 g.m.m².day¹.Pa¹), increased the hydrophobicity (contact angle from 10-40° to 80-90°), but decreased the stiffness (from 3.1 GPa to 1.3 Gpa) of the BNC composite. The mechanical and barrier properties of the obtained layered composite were considered suitable for food packaging applications. Although the results obtained being important for food packaging, its commercial use is still far off due to production costs and low production capacity, especially when compared to plant-based nanocellulose [1]. Nevertheless, BNC is a proven material to support substances that play an active/intelligent role in food packaging, with ability to carry and release active substances [4, 5]. Therefore, a functionalized BNC film was developed, by in situ incorporating zinc oxide nanoparticles (ZnONPs). The synthesis of ZnONPs was based on co-precipitation method, using zinc acetate and sodium hydroxide (NaOH) (added dropwise) as reactants. In order to prevent aggregation of ZnO NPs, polyvinyl alcohol (PVOH) was used as capping agent. Overall, dropwise addition of NaOH in zinc acetate-PVOH (with immersed BNC), allowed the production of ZnONPs (144 nm), with low polydispersity index (0.139) and a homogeneous distribution of ZnONPs on the BNC. Concerning the antimicrobial activity, the minimum ZnO dosage for antimicrobial activity was 20%mZnO/mBNCZnO, being effective on gram bacteria (such Escherichia Coli) but only on some gram + bacteria (such Staphylococcus Aureus). The migration of ZnO onto food simulators are under testing.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

HTLV-I/II e doadores de sangue: determinantes associados à soropositividade em população de baixo risco

OBJECTIVE: Blood donors in Brazil have been routinely screened for HTLV-I/II since 1993. A study was performed to estimate the prevalence of HTLV-I/II infection in a low risk population and to better understand determinants associated with seropositivity. METHODS: HTLV-I/II seropositive (n=135), indeterminate (n=167) and seronegative blood donors (n=116) were enrolled in an open prevalence prospective cohort study. A cross-sectional epidemiological study of positive, indeterminate and seronegative HTLV-I/II subjects was conducted to assess behavioral and environmental risk factors for seropositivity. HTLV-I/II serological status was confirmed using enzyme-linked immunosorbent assay (EIA) and Western blot (WB). RESULTS: The three groups were not homogeneous. HTLV-I/II seropositivity was associated to past blood transfusion and years of schooling, a marker of socioeconomic status, and use of non-intravenous illegal drugs. CONCLUSIONS: The study results reinforce the importance of continuous monitoring and improvement of blood donor selection process.OBJETIVO: Doadores de sangue no Brasil têm sido avaliados sorologicamente para o HTLV-I/II desde 1993. Assim, realizou-se estudo para estimar a prevalência dessa infecção em população de baixo risco e para melhor compreender os determinantes associados à soropositividade. MÉTODOS: Doadores de sangue soropositivos (n=135), soroindeterminados (n=167) e soronegativos (n=116) foram arrolados como participantes de uma coorte aberta e prevalente. Estudo transversal dos participantes desses três grupos avaliou fatores de risco comportamentais e ambientais para soropositividade. O status sorológico foi definido usando a reação de EIA (enzyme linked immunosorbent assay) e o teste Western blot (WB). RESULTADOS: Os três grupos apresentaram heterogeneidade entre si. A soropositividade mostrou-se associada à história pregressa de transfusão de sangue, em nível educacional, como um marcador de condição socioeconômica e ao uso de drogas ilegais não endovenosas. CONCLUSÕES: Os resultados confirmam a importância de um monitoramento e refinamento do processo de seleção dos doadores de sangue