105 research outputs found

    Literacy Sponsorship and Official Paratexts: Promoting Character Literacy through the For the Strength of Youth Booklets (1965-2011)

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    Literacy sponsors continue to play a dynamic and integral role in acquiring and learning literacy knowledge and skills (fluency) within discourse communities. This thesis examines how a religious literacy sponsor, The Church of Jesus Christ of Latter-day Saints, utilizes the For the Strength of Youth (FSOY) publications and official paratexts to actively promote religious literacy and character development in the lives of adolescents. This thesis focuses specifically on the 2011 edition of the FSOY to explore the impact that recent advancements in digital technology have had on the evolution of the main-body text and official paratexts. A textual and paratextual analysis serves to illustrate how the Church promotes literacy acquisition and learning within the religious discourse community

    Micro X-ray fluorescence imaging coupled with chemometrics to detect and classify asbestos fibers in demolition waste

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    Asbestos was largely used in the past by several countries all over the world. From 1900 to 1990 asbestos-containing materials (ACMs) were produced in large amounts and mainly utilized to produce insulation, flame retardant materials, as well as to improve the mechanical and the chemical characteristics of construction materials. Its extensive use has therefore led to the presence of fibers in existing buildings and within the construction and demolition waste. A fast, reliable and accurate recognition of ACMs represents an important target to be reached. In this paper the use of micro X-ray fluorescence (micro-XRF) technique coupled with a statistical multivariate approach was applied and discussed with reference to ACMs characterization. Different elemental maps of the ACMs were preliminary acquired in order to evaluate distribution and composition of asbestos fibers, then samples energy spectra where collected and processed using chemometric methods to perform an automatic classification of the different typologies of asbestos fibers. Spectral data were analyzed using PLS-Toolbox™ (Eigenvector Research, Inc.) running into Matlab® (The Mathworks, Inc.) environment. An automatic classification model was then built and applied. Results showed that asbestos fibers were correctly identified and classified according to their chemical composition. The proposed approach, based on micro-XRF analysis combined with an automatic classification of the elemental maps, is not only effective and non-destructive, it is fast, and it does not require the presence of a trained operator. The application of the developed methodology can help to correctly characterize and manage demolition waste where ACMs are present

    Chrysotile detection in soils with proximal hyperspectral sensing and chemometrics

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    In this work the authors present an innovative methodology, based on proximal hyperspectral sensing and chemometric techniques, aimed at detecting asbestos containing soils. Short Wave InfraRed (SWIR) reflectance spectra of reference samples containing known chrysotile fractions were collected in laboratory. Since the identification of asbestos containing soils depends on the contaminant mass percentage (weight/weight), two supervised multivariate data projection methods were evaluated for asbestos concentration prediction. The first results are reported here, together with advantages and limits of the analytical methods. Orthogonal Partial Least Squares (PLS) regression showed the lowest error in prediction and the highest coefficient of determination in prediction. This technique would support screening activities frequently conducted during environmental assessment and remediation projects

    Shedding light on surface exposition of poly(ethylene glycol) and folate targeting units on nanoparticles of poly(ε-caprolactone) diblock copolymers: beyond a paradigm

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    Polymeric nanoparticles (NPs) of poly(\u3b5-caprolactone) (PCL) covered with a hydrophilic poly(ethylene glycol) (PEG) shell are usually prepared from diblock PEG-PCL copolymers through different techniques. Furthermore PEG, NPs can be decorated with targeting ligands to accumulate in specific cell lines. However, the density and conformation of PEG on the surface and its impact on the exposition of small targeting ligands has been poorly considered so far although this has a huge impact on biological behaviour. Here, we focus on PEG-PCL NPs and their folate-targeted version to encourage accumulation in cancer cells overexpressing folate receptor \u3b1. NPs were prepared with mixtures of PEG-PCL with different PEG length (short 1.0kDa, long 2.0kDa,) and a folate-functionalized PEG-PCL (PEG 1.5kDa) by the widely employed solvent displacement method. In depth characterization of NPs surface by 1H NMR, fluorescence and photon correlation spectroscopy evidenced a PEGylation extent below 7% with PEG in a mushroom conformation and the presence of folate more exposed to water pool in the case of copolymer with short PEG. NPs with short PEG adsorbed HSA forming a soft corona without aggregating. Although limited, PEGylation overall reduced NPs uptake in human macrophages. Uptake of NPs exposing folate prepared with short PEG was higher in KB cells (FR+) than in A549 (FR-), occurred via FR-receptor and involved lipid rafts-dependent endocytosis. In conclusion, the present results demonstrate that PEG length critically affects protein interaction and folate exposition with a logical impact on receptor-mediated cell uptake. Our study highlights that the too simplistic view suggesting that PEG-PCL gives PEG-coated NPs needs to be re-examined in the light of actual surface properties, which should always be considered case-by-case

    Lignosulfonates as fire retardants in wood flour-based particleboards

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    Wood flour particleboards (WFP), like other wood-based items, require the addition of fire retardants (FRs) to reduce their high flammability. In this work, a waste lignosulfonate (CaLS) from paper mill is used as a low-cost FR to reduce WFP flammability. CaLS is purified by dialysis and the dialysed lignosulfonate (LD) is used, alone or combined with ammonium polyphosphate (APP), as a FR additive in the preparation of urea-formaldehyde WFP. The fire behaviour of the modified WFPs is studied by cone calorimetry. The use of 15 wt.% LD reduces the peak of heat release rate (HRR) and total smoke production by 25%, also increasing char formation. HRR peak is further reduced up to 40%, if APP is introduced in the formulation. This work discloses a viable and cost-effective strategy for improving the fire retardancy performance of WFP by partial replacement of a commercial FR with a fully renewable additive, isolated through a green and cost-effective process. Copyright © 2019 Stefania Angelini et al

    Development of a petrographic classification of fly-ash components from coal combustion and co-combustion. (An ICCP Classification System, Fly-Ash Working Group – Commission III.)

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    A new system for the microscopic classification of fly-ash components has been developed by the Fly-Ash Working Group, Commission III of the ICCP and is presented herein. The studied fly-ashes were obtained from the combustion of single coals of varied rank, coal blends, and coals blended with other fuels (biomass, petroleum coke), in different operating conditions and by means of different technologies. Microscopic images of the fly-ash samples were used to test the optical criteria proposed for classifying the fly-ash components. The classification system developed is based on a small number of microscopic criteria, subdivided into six independent levels or categories, three of which are directed at whole particle identification on the basis of nature, origin and type of fly-ash particle, while the other three levels are directed at the smaller section identification on the basis of character, structure and optical texture of unburned carbons. To classify the inorganic components of the fly-ash, the criterion proposed is composition in terms of metallic/non-metallic character. To establish the classification criteria the petrographers involved in the work performed three successive round robins. Evaluation of the results by using firstly descriptive statistics and then the criteria and parameters employed by the ICCP in their accreditation programs indicated that the classification of the fly-ash components was accurate and that there was only a minor bias. The main conclusion of this study was that the proposed criteria are valuable for identifying, and classifying fly-ash components and for describing the optical properties of fly-ash particles
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