81 resultados para Production of hydroxyl-terminated liquid natural rubber


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Deleterious responses to pathogens during infancy may contribute to infection and associated asthma. Chlamydia respiratory infections in early life are common causes of pneumonia and lead to reduced lung function and asthma. We investigated the role of interleukin-13 (IL-13) in promoting early-life Chlamydia respiratory infection, infection-induced airway hyperresponsiveness (AHR), and severe allergic airway disease (AAD). Infected infant Il13−/− mice had reduced infection, inflammation, and mucus-secreting cell hyperplasia. Surprisingly, infection of wild-type (WT) mice did not increase IL-13 production but reduced IL-13Rα2 decoy receptor levels compared with sham-inoculated controls. Infection of WT but not Il13−/− mice induced persistent AHR. Infection and associated pathology were restored in infected Il13−/− mice by reconstitution with IL-13. Stat6−/− mice were also largely protected. Neutralization of IL-13 during infection prevented subsequent infection-induced severe AAD. Thus, early-life Chlamydia respiratory infection reduces IL-13Rα2 production, which may enhance the effects of constitutive IL-13 and promote more severe infection, persistent AHR, and AAD.

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Particles having at least regions of at least one metal oxide having nano-sized grains are produced by providing particles of a material having an initial, nonequiaxed particle shape, prepg. a mixt. of these particles and at last one metal oxide precursor, and treating the mixt. such that the precursor reacts with the particles. The process can be a co-pptn. process, sol-gel synthesis, micro-emulsion method, surfactant-based process, or a process that uses polymers. Complex metal oxide nanoparticles are produced by (a) prepg. a soln. contg. metal cations, (b) mixing the soln. with a surfactant to form micelles within the soln., and (c) heating the micellar liq. to form metal oxide and to remove the surfactant. The formed metal oxide particles have essentially the same morphol. (particle size and shape) as the initial morphol. of the material particles provided. [on SciFinder(R)]

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A method of producing particles having nano-sized grains comprises the steps of: (a) prepg. a soln. contg. one or more metal cations; (b) mixing the soln. from step (a) with one or more surfactants to form a surfactant/liq. mixt. and (c) heating the mixt. from step (b) above to form the particles. [on SciFinder(R)]

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A method of producing porous complex oxides includes the steps of providing a mixt. of (a) precursor elements suitable to produce the complex oxide, or (b) one or more precursor elements suitable to produce particles of the complex oxide and one or more metal oxide particles; and (c) a particulate carbon-contg. pore-forming material selected to provide pore sizes in the range of 7-250 nm, and treating the mixt. to (i) form the porous complex oxide in which two or more of the precursor elements from (a) above or one or more of the precursor elements and one or more of the metals in the metal oxide particles from (b) above are incorporated into a phase of the complex metal oxide and the complex metal oxide has grain sizes in the range of 1-150 nm, and (ii) removing the pore-forming material under conditions such that the porous structure and compn. of the complex oxide is substantially preserved. The method may be used to produce nonrefractory metal oxides as well. The mixt. further includes a surfactant, or a polymer. [on SciFinder(R)]

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Porous complex oxides are produced by reacting metal oxide precursors in the presence of a pore-forming material to provide pore sizes in the range of 7-250 nm, followed by removal of the pore-forming material under conditions preserving the structure and compn. of the formed oxides. The pore-forming material are carbon black particles having a particle size of 10-100 nm. The carbon particles are removed from the formed oxide by heating at 100-300°. A surfactant can be added to the reaction mixt. [on SciFinder(R)]

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A method of producing particles having nano-sized grains comprises the steps of: (a) prepg. a soln. contg. one or more metal cations; (b) mixing the soln. from step (a) with one or more surfactants to form a surfactant/liq. mixt. and (c) heating the mixt. from step (b) above to form the particles. [on SciFinder(R)]

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A method for producing metal oxide particles having nano-sized grains is disclosed. A solution of metal cations is mixed with surfactant under conditions such that surfactant micelles are formed. This mixture is then heated to form the metal oxide particles; this heating step removing the surfactant, forming the metal oxide and creating the pore structure of the particles. The pore structures are disordered. This method is particularly advantageous for production of complex (multi-component) metal oxides in which the different atomic species are homogeneously dispersed.

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Bi-2212 thick film on silver tapes are seen as a simple and low cost alternative to high temperature superconducting wires produced by the Powder In Thbe (PIT) technique, particularly in react and wind applications. A rig for the continuous production of Bi-2212 tapes for use in react and wind component manufacture has been developed and commissioned. The rig consists of several sections, each fully automatic, for task specific duties in the production of HTS tape. The major sections are: tape coating, sintering and annealing. High temperature superconducting tapes with engineering critical current densities of 10 kA/cm2 (77 K, self field), and lengths of up to 100 m have been produced using the rig. Properties of the finished tape are discussed and results are presented for current density versus bend radius and applied strain. Depending on tape content and thickness, irreversible strain tirrm varies between 0.04 and 0.1 %. Cyclic bending tests when applied strain does not exceed Eirrm showed negligible reduction in J c along the length of the tape.

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In this paper we will examine passenger actions and activities at the security screening points of Australian domestic and international airports. Our findings and analysis provide a more complete understanding of the current airport passenger security screening experience. Data in this paper is comprised of field studies conducted at two Australian airports, one domestic and one international. Video data was collected by cameras situated either side of the security screening point. A total of one hundred and ninety-six passengers were observed. Two methods of analysis are used. First, the activities of passengers are coded and analysed to reveal the common activities at domestic and international security regimes and between quiet and busy periods. Second, observation of passenger activities is used to reveal uncommon aspects. The results show that passengers do more at security screening that being passively scanned. Passengers queue, unpack the required items from their bags and from their pockets, walk through the metal-detector, re-pack and occasionally return to be re-screened. For each of these activities, passengers must understand the procedures at the security screening point and must co-ordinate various actions and objects in time and space. Through this coordination passengers are active participants in making the security checkpoint function – they are co-producers of the security screening process.

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Rice ragged stunt virus (RRSV) is an important pathogen of rice affecting its cultivation in South and South East Asia. An approach based on pathogen derived resistance (PDR) was used to produce RRSV resistant rice cultivars. Sequences from the coding region of RRSV genome segments 7 and 10 (non-structural genes), and 5, 8 and 9 (structural genes) were placed in sense or antisense orientation behind the plant expression promoters CaMV35S, RolC, Ubil, Actl and RBTV. Rice cultivars Taipei 309 and Chinsurah Boro II were transformed by biolistic and/or Agrobacterium-mediated delivery of one or more of these PDR gene constructs. A large number of transgenic lines were produced from calli derived from mature or immature embryos, co-bombarded with the marker gene hph encoding hygromycin resistance and RRSV PDR genes or co-cultivated with strains having the binary vector containing these two genes. Both Mendelian and non-Mendelian segregations were observed in transgenic progeny, especially with transgenic lines produced by biolistics. Preliminary tests conducted in China on selected transgenic lines indicate that plants with RRSV segment 5 antisense PDR gene confer RRSV resistance.

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Successful control of sexually transmitted diseases (STDs) through vaccination will require the development of vaccine strategies that target protective immunity to both the female and male reproductive tracts (MRT). In the male, the immune privileged nature of the male reproductive tract provides a barrier to entry of serum immunoglobulins into the male reproductive ducts, thereby preventing the induction of protective immunity using conventional injectable vaccination techniques. In this study we investigated the potential of intranasal (IN) immunization to elicit anti-chlamydial immunity in BALB/c male mice. Intranasal immunization with Chlamydia muridarum major outer membrane protein (MOMP) admixed with cholera toxin (CT) resulted in high levels of MOMP-specific IgA in prostatic fluids (PF) and MOMP-specific IgA-secreting cells in the prostate. Prostatic fluid IgA inhibited in vitro infection of McCoy cells with C. muridarum. Using RT-PCR we also show that mRNA for the polymeric immunoglobulin receptor (PIgR), which transports IgA across mucosal epithelia, is expressed only in the prostate but not in other regions of the male reproductive ducts upstream of the prostate. These data suggest that using intranasal immunization to target IgA to the prostate may protect males against STDs while at the same time maintaining the state of immune privilege within the MRT.

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Much of what is written about digital technologies in preschool contexts focuses on young children’s acquisition of skills rather than their meaning-making during use of technologies. In this paper, we consider how the viewing of a YouTube video was used by a teacher and children to produce shared understandings about it. Conversation analysis of talk and interaction during the viewing of the video establishes some of the ways that individual accounts of events were produced for others and then endorsed as shared understandings. The analysis establishes how adults and children made use of verbal and embodied actions during interactions to produce shared understandings of the YouTube video, the events it recorded and written commentary about those events

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In this chapter the authors discuss and informal learning settings such as fan fiction sites and their relations to teaching and learning within formal learning settings. Young people today spend a lot of time with social media built on user generated content. These media are often characterized by participatory culture which offers a good environment for developing skills and identity work. In this chapter the authors problematize fan fiction sites as informal learning settings where the possibilities to learn are powerful and significant. They also discuss the learning processes connected to the development of literacies. Here the rhetoric principle of “imitatio” plays a vital part as well as the co-production of texts on the sites, strongly supported by the beta reader and the power of positive feedback. They also display that some fans, through the online publication of fan fiction, are able to develop their craft in a way which previously have been impossible.

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Sugarcane products represent an abundant and relatively low cost carbon resource that can be utilised to produce chemical intermediates such as levulinic acid and furanics. These chemicals can be easily upgraded to commodity and specialty chemicals and biofuels by high yielding and well established technologies. However, there are challenges and technical hurdles that need to be overcome before these chemical intermediates can be cost-effectively produced in commercial quantities. The paper reviews production of levulinic acid and furanics from sugars by homogeneous mineral acid catalysts, and reports on preliminary studies on the production of these compounds with environmentally friendly biodegradable sulfonic acids. The yields (>50% of theoretical) of levulinic acid, formic acid and furfural obtained with these organic acids are comparable to that of sulphuric acid currently used for their production.

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There are many attractive alternatives to produce chemicals similar to those currently produced from fossil fuel resources. The most viable renewable resource of fixed carbon is biomass. This paper examines processing conditions for the production and recovery of furanics from bagasse as well as bagasse pulp. It is shown that bio-oil consisting mainly of furanics (~84% chloromethly furfural) may be obtained in yields of ~78% and ~87% by weight from bagasse and bagasse pulp respectively using a biphasic acid hydrolysis system. The biphasic system consists of an organic layer of dichloroethane and an aqueous phase of concentrated hydrochloric acid. Generally the lower the impurity content and the higher the cellulose content, the higher the furanics yield.