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This article presents the results of a study that analyses students' historical narratives of the nation in relation to historical consciousness and how their sense of self-identification with groups affects their narrative structure and orientation. This study was conducted with French Canadian students registered in two high schools (n=58) and one university (n=18) in Ottawa, the federal capital of Canada. I found that a strong sense of identification leads young people to construct more engaging and militant stories of the collective past, with greater historical appropriation (using the collective 'we') and a sense of continuity with past actualities. I then discuss the implications of this study for research on the narrative competence of historical consciousness and what history education might do in school to promote historical consciousness in Canada. [ABSTRACT FROM AUTHOR]

This article presents the results of a Canadian study of prospective history teachers conducted in 2012-2013. Using an online questionnaire to assess a broad range of questions pertaining to their knowledge of history, their trust in historical sources, their experiences in high school and university classes, and their views about school history, it offers new empirical evidence on how the growing generation of Canadian teachers are prepared for the teaching profession. Implications of this study for teacher education and practice teaching are also presented. [ABSTRACT FROM AUTHOR]

Abstract: Dextran hydrogels have been previously investigated as drug delivery vehicles and more recently as macroporous scaffolds; however, the non-cell-adhesive nature of dextran has limited its utility for tissue engineering. To overcome this limitation, macroporous scaffolds of methacrylated dextran (Dex-MA) copolymerized with aminoethyl methacrylate (AEMA) were synthesized, thereby introducing primary amine groups for covalent immobilization of extracellular-matrix-derived peptides. The amino group density for hydrogels copolymerized with 0.5wt% AEMA was found to be 36.1±0.4μmol/cm3 by elemental analysis. To further enhance cellular interaction, poly(Dex-MA-co-AEMA) hydrogels were modified with either CRGDS or a mixture of CDPGYIGSR and CQAASIKVAV (1:1, v/v) using sulfo-(N-maleimidomethyl)cyclohexane-1-carboxylate (sulfo-SMCC). The immobilized peptide concentration was determined using amino acid analysis at: 2.6±0.9μmol/cm3 for CRGDS-derived hydrogels and 2.2±0.3μmol/cm3 plus 1.9±0.2μmol/cm3 for CDPGYIGSR plus CQAASIKVAV-derived hydrogels, respectively. Cellular interactions of primary embryonic chick dorsal root ganglia (DRGs) were compared on the hydrogels. Cell adhesion and neurite outgrowth on poly(Dex-MA) increased with copolymerization of AEMA and further improved with peptide modification and significantly for CDPGYIGSR/CQAASIKVAV-derived poly(Dex-MA-co-AEMA) hydrogels. Moreover, DRGs penetrated within the first 600μm of the scaffolds, thereby demonstrating the potential of this scaffold for guided cell and axonal regeneration in vivo. [Copyright &y& Elsevier]

Abstract: Dextran hydrogels have been studied as drug delivery vehicles but not as scaffolds for tissue-engineering likely because previously synthesized dextran hydrogels had pores too small for cell penetration. Our goal was to create macroporous, interconnected dextran scaffolds. To this end, we took advantage of the liquid–liquid immiscibility of poly(ethylene glycol) and methacrylated dextran during radical crosslinking of the methacrylated moieties. By controlling the degree of methacrylate substitution on dextran, dextran molar mass and PEG concentration, macroporous hydrogels were created. The presence of PEG in solution had a significant effect on the final morphology of the dextran hydrogel leading to the formation of different types of structures, from microporous gel to macroporous gel-wall to a macroporous interconnected-beaded structure. A series of formulation diagrams were prepared which allowed us to determine which conditions led to the formation of macroporous interconnected-beaded scaffolds. Dextran macroporous interconnected-beaded gels had a high water content, between 89% and 94%, a homogeneous morphology, determined by scanning electron microscopy, with interconnected macroporous pores, as determined by protein diffusivity where the effective diffusion coefficients of BSA were calculated to be 3.1×10−7 cm2/s for Dex-MA 40kDa DS 5 and 1×10−7 cm2/s for Dex-MA 6kDa DS10, which are similar to that of BSA in water, 5.9×10−7 cm2/s. Mercury intrusion porosimetry showed that the macroporous interconnected-beaded scaffolds had a bimodal distribution of macropores, with a median diameter of 41μm, interconnected by throats, which had a median diameter of 11μm. Together, these data suggest that the dextran scaffolds will be advantageous in applications that require an interconnected macroporous geometry, such as those of tissue engineering where cell penetration and nutrient diffusion are necessary for tissue regeneration. [Copyright &y& Elsevier]

History is an often unsettling and sometimes uncomfortable subject. It is controversial and often very sensitive. There is some consensus about its importance in the school curriculum but much less agreement about what it is for (Slater 1995: xi). [ABSTRACT FROM AUTHOR]

Height equivalent to a theoretical plate (HETP) calculations, essential for the design of randomly packed distillation columns were extracted from the open literature to generate a working database including over 2350 measurements (only total molar reflux data). The merging of mass transfer characteristics from non-aqueous and aqueous separation experiments has instigated the generation of a consistent correlation predicting HETP. Based on results presented elsewhere for absorption and stripping conditions (Ind. Eng. Chem. Res. 41 (2002) 4911), a set of artificial neural network (ANN) correlations for the gas–liquid interfacial area (aw) and the pure local mass transfer coefficients (kγ, γ=G or L) was proposed with the following dimensionless structures: aw/aT=f(ReL, FrL, EoL, I, χ, K) and Shγ=f(Reγ, Frγ, Scγ, χ). The gas–liquid interfacial area and the pure local mass transfer coefficients were extracted using a reconciliation procedure which combined actually measured interfacial areas with pseudo-interfacial areas inferred from the actually measured volumetric mass transfer coefficients (kLaw, KLaw, kGaw, KGaw—absorption and stripping) and HETP (distillation). The neural network weights of the two aw and kγ correlations were adjusted using a least-squared composite criterion simultaneously over the six mass transfer parameters’ databases. The optimized set of ANN correlations yielded an average absolute relative error (AARE) of 21.3% for the 2357 HETP measurements available. Likewise, the measured interfacial area and volumetric mass transfer coefficients (3770 data) were correlated with an AARE of approximately 26.5%, which undeniably proves the intimate correspondence of absorption and distillation mass transfer characteristics in randomly packed towers. HETP predictions remain as well in accordance with the physical evidence reported in the literature. [Copyright &y& Elsevier]

Lipid interaction with ePTFE arterial prostheses has been identified in previous studies as being one of the causes leading to graft failure. Our research group has previously proposed a mathematical model of the lipid uptake mechanism in Teflon® prostheses as two first-order reactions based on in vitro experiments. The present study sought to determine whether surface modification with methoxy poly(ethylene glycol) (MPEG) derivatives of various molecular weights modified the kinetics of lipid transport through microporous PTFE membranes. PTFE films and ePTFE tubular microporous membranes were functionalized with amine groups using an ammonia radio frequency glow discharge plasma. MPEGs were conjugated as succinimidyl activated esters on the aminated-PTFE surfaces. In order to maximize the surface coverage by MPEGs, the conjugation reactions were performed under conditions near the cloud point. XPS and contact angle analyses confirmed the ability to covalently graft activated MPEGs to amino-functionalized PTFE surfaces of the films and microporous membranes. Lipid adsorption onto PTFE films monitored by ATR-FTIR spectroscopy demonstrated that the surface coverage by each MPEG resulted in a significant decrease in lipid adsorption regardless of the MPEG molecular weight (Mw). ATR-FTIR spectroscopy and FTIR microscopy were used to characterize lipid adsorption onto the PTFE microporous membrane surface and lipid absorption across the microporous structure, respectively. The surface modification by the MPEG, regardless of its Mw, resulted in both decrease of lipid adsorption onto the surface of the modified membrane and delayed lipid uptake kinetics. It was concluded that MPEG anchored to the surface of a PTFE microporous membrane may modify mass transport through the ePTFE porous structure. [Copyright &y& Elsevier]