13Polyhydroxyalkanoates (PHAs) are bioplastics that can replace conventional 14 petroleum derived products in various applications. One of the major barriers for 15 their widespread introduction in the market is the higher production costs when 16 compared with their petrochemical counterparts. In this work, a process was 17 successfully implemented with high productivity based on wheat straw, a cheap 18 and readily available agricultural residue, as raw material. The strain 19Burkholderia sacchari DSM 17165 which is able to metabolize glucose, xylose 20 and arabinose, the main sugars present in wheat straw hydrolysates (WSH), 21 was used. Results in shake flask showed that B. sacchari cells accumulated ca 22 * Corresponding author. Tel.: +351 21 8419137; fax: +351 21 8419062.e-mail address: teresa.cesario@ist.utl.pt 2 70 % g P(3HB)/g cell-dry-weight with a yield of polymer on sugars (Y P/S ) of 0.18 23 g/g when grown on a mixture of commercial C6 and C5 sugars (control), while 24 these values reached ca 60 % g P(3HB)/g cell-dry-weight and 0.19 g/g, 25 respectively, when WSHs were used as carbon source. In fed-batch cultures 26 carried out in 2L stirred tank reactors on WSH, a maximum polymer 27 concentration of 105 g/L was reached after 61 h of cultivation corresponding to 28 an accumulation of 72% of CDW. Polymer yield and productivity were 0.22 g 29 P(3HB)/g total sugar consumed and 1.6 g/L . h, respectively. The selected 30 feeding strategy successfully overcame the carbon catabolite repression 31 phenomenon observed in sugar mixtures containing hexoses and pentoses. 32 This is the first work describing fed-batch cultivations aiming at PHA production 33 using real lignocellulosic hydrolysates. Additionally, the P(3HB) volumetric 34 productivities attained are, by far, the highest achieved ever on agricultural 35 wastes hydrolysates. 36 Keywords 37Wheat straw hydrolysates ; poly 3-hydroxybutyrate; Burkholderia sacchari; carbon

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This paper focuses on the commodification processes and the aestheticization practices that shape gated communities and on the way these are connected to their segregational dimension, which is illustrated through the case of the Lisbon Metropolitan Area (LMA). First, I discuss the (increasing) aestheticization of commodities, emphasising some of the more problematic theoretical issues it involves. Following this discussion I present and analyse the 'Lisbon case'. I provide a brief overview of gated communities in the LMA and then present and analyse the results obtained through a content analysis of LMA gated community advertisements and observation of their site semantics as conveyed through general built form, including physical location, planning, architecture, landscaping, and toponymy. I relate these findings to the LMA gated community market characteristics and to the broader prevailing socio-spatial context regarding their emergence.

Efficient production of poly-3-hydroxybutyrate (P(3HB)) based on glucose-xylose mixtures simulating different types of lignocellulosic hydrolysate (LCH) was addressed using Burkholderia sacchari, a wild strain capable of metabolizing both sugars and producing P(3HB). Carbon catabolite repression was avoided by maintaining glucose concentration below 10g/L. Xylose concentrations above 30g/L were inhibitory for growth and production. In fed-batch cultivations, pulse size and feed addition rate were controlled in order to reach high productivities and efficient sugar consumptions. High xylose uptake and P(3HB) productivity were attained with glucose-rich mixtures (glucose/xylose ratio in the feed=1.5w/w) using high feeding rates, while with xylose-richer feeds (glucose/xylose=0.8w/w), a lower feeding rate is a robust strategy to avoid xylose build-up in the medium. Xylitol production was observed with xylose concentrations in the medium above 30-40g/L. With sugar mixtures featuring even lower glucose/xylose ratios, i.e. xylose-richer feeds (glucose/xylose=0.5), xylonic acid (a second byproduct) was produced. This is the first report of the ability of Burkholderia sacchari to produce both xylitol and xylonic acid.

A technique for poly-3-hydroxybutyrate (P(3HB)) extraction with safer, non-chlorinated solvents, was developed, aiming to attain high recovery yields and purities. A wide range of solvents was selected from the GlaxoSmithKline guide as sustainable industrial solvents and the solubility of P(3HB) on those solvents calculated using predictive equations from literature. Anisole, * Corresponding author: Tel.: +351 21 8419137; Fax: +351 21 8419062. e-mail address: teresa.cesario@tecnico.ulisboa.pt + Current address: Politecnico di Milano, Dipartimento di Chimica Materiali e Ingegneria Chimica "Giulio Natta". Via Mancinelli, 7 -20131 Milano MI 2 cyclohexanone and phenetole were used as extraction solvents and the relevant process variables (extraction temperature, extraction time and mass of cells/solvent volume ratio) were optimized.Polymer recovery yields of 97% and 93% were obtained with anisole and cyclohexanone, respectively, at 120-130°C using a cell/solvent ratio of 1.5% (w/v). Maximum polymer purities using these experimental conditions were 98% for both solvents. Recovery yields and polymer purity attained with chloroform (reference solvent) were 97 and 98%, respectively. Higher cell/solvent ratios of 6.0 % (w/v) showed slightly lower recovery yields and purities The average molecular weight and the thermal properties of the polymers extracted with the alternative solvents were comparable to those of the polymers obtained by chloroform extraction, showing that the applied conditions did not significantly alter the properties of the extracted P(3HB).

Burkholderia sacchari DSM 17165 is able to grow and produce poly(3-hydroxybutyrate) both on hexoses and pentoses. In a previous study, wheat straw lignocellulosic hydrolysates (WSH) containing high C6 and C5 sugar concentrations were shown to be excellent carbon sources for P(3HB) production.Using a similar feeding strategy developed for P(3HB) production based on WSH, fedbatch cultures were developed aiming at the production of the copolymer P(3HB-co-4HB) (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) by B. sacchari. The ability of this * Corresponding author. Tel.: +351 21 8419137; Fax: +351 21 8419062.e-mail address: teresa.cesario@tecnico.ulisboa.pt 2 strain to synthesize P(3HB-co-4HB) was first shown in shake flasks using gammabutyrolactone (GBL) as precursor of the 4HB units.Fed-batch cultures using glucose as carbon source (control) and GBL were developed to achieve high copolymer productivities and 4HB incorporations. The attained P(3HB-co-4HB) productivity and 4HB molar % were 0.7 g/(L·h) and 4.7 molar %, respectively.The 4HB incorporation was improved to 6.3 and 11.8 molar % by addition of 2 g/L propionic and acetic acid, respectively. When WSH were used as carbon source under the same feeding conditions, the values achieved were 0.5 g/(L·h) and 5.0 molar %, respectively. Burkholderia sacchari, a strain able to produce biopolymers based on xylose-rich lignocellulosic hydrolysates, is for the first time reported to produce P(3HB-co-4HB) using gamma butyrolactone as precursor.

Abstract. This paper examines the main features of the social production process of condomínios fechados across the Lisbon Metropolitan Area. This residential form first appeared in Portugal in the 1980's and spread quickly in the 1990's. The article opens with a preliminary analysis of the development of secured residential complexes, aimed at understanding its specificity and pinpointing the main factors involved in its social production. In this analysis, we do not focus on the Lisbon Metropolitan Area (LMA) alone but rather adopt a broader approach. In the second chapter we describe the research methods used, such as a survey of condomínios fechados built in the Lisbon Metropolitan Area between 1985 and 1999, interviews with social actors and content analysis of promotional materials. Finally, we present selected research results and discuss several issues central to understanding the social production of gated housing estates in the LMA, including the importance of foreign modeis, the supply side agency of the real estate market, and the broader social context.

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