Anatomy education environment measurement inventory (AEEMI): a cross-validation study in Malaysian medical schools

Background: The Anatomy Education Environment Measurement Inventory (AEEMI) evaluates the perception of medical students of educational climates with regard to teaching and learning anatomy. The study aimed to cross-validate the AEEMI, which was previously studied in a public medical school, and proposed a valid universal model of AEEMI across public and private medical schools in Malaysia. Methods: The initial 11-factor and 132-item AEEMI was distributed to 1930 pre-clinical and clinical year medical students from 11 medical schools in Malaysia. The study examined the construct validity of the AEEMI using exploratory and confirmatory factor analyses. Results: The best-fit model of AEEMI was achieved using 5 factors and 26 items (χ 2 = 3300.71 (df = 1680), P < 0.001, χ 2/df = 1.965, Root Mean Square of Error Approximation (RMSEA) = 0.018, Goodness-of-fit Index (GFI) = 0.929, Comparative Fit Index (CFI) = 0.962, Normed Fit Index (NFI) = 0.927, Tucker–Lewis Index (TLI) = 0.956) with Cronbach’s alpha values ranging from 0.621 to 0.927. Findings of the cross-validation across institutions and phases of medical training indicated that the AEEMI measures nearly the same constructs as the previously validated version with several modifications to the item placement within each factor. Conclusions: These results confirmed that variability exists within factors of the anatomy education environment among institutions. Hence, with modifications to the internal structure, the proposed model of the AEEMI can be considered universally applicable in the Malaysian context and thus can be used as one of the tools for auditing and benchmarking the anatomy curriculum

A method for controlling the aggregation of gold nanoparticles: Tuning of optical and spectroscopic properties

Gold nanoparticles (AuNPs) have many interesting optical properties, which are derived from their surface plasmon resonance (SPR). However, the SPR of single AuNPs occurs around 520 nm, which is a limitation for biomedical imaging applications, because the maximum falls outside the tissue transparency window (similar to 650-1000 nm). Here the aggregation of AuNPs is mediated by balancing aggregation and steric stabilization processes. This is achieved by varying the relative amounts of hydrophobic small molecules, which act as aggregating agents, and end functional hydrophilic polymers that serve as steric stabilizing agents. This approach allows the position of the SPR shifted into the tissue transparency window, while maintaining colloidal stability. Importantly, increased depolarized scattering and surface enhanced Raman scattering (SERS) cross sections in this region are achieved compared to the single nanoparticles. By varying the structure of the aggregating agent slightly, the SERS spectra exhibit significant changes, thus demonstrating the potential to encode different aggregates. The aggregates have potential applications in biomedical imaging, as an encoding strategy for combinatorial chemistry, and for use in flow cytometry applications

Synthesis and characterisation of hybrid polymer-gold nanoparticles : towards novel biosensors

A method is reported for the self-assembly of hybrid polymer-gold nanoparticles. To this end a methacrylate block copolymer has been synthesized by radical addition fragmentation chain transfer (RAFT) polymerization. The resultant block copolymer has a sulfur-containing dithiocarbamate end group. Due to the high degree of interaction of sulfur containing functionalities and gold, the dithiocarbamate end groups have been used as a means to generate hybrid polymer gold nanoparticles. The synthesized polymers and nanoparticles have been characterized by a series of analytical techniques, including diffusion ordered NMR spectroscopy (DOSY), which has been utilized to demonstrate block copolymer formation and formation of the polymer-gold hybrids

A Method for Controlling the Aggregation of Gold Nanoparticles: Tuning of Optical and Spectroscopic Properties

Gold nanoparticles (AuNPs) have many interesting optical properties, which are derived from their surface plasmon resonance (SPR). However, the SPR of single AuNPs occurs around 520 nm, which is a limitation for biomedical imaging applications, because the maximum falls outside the tissue transparency window (∼650–1000 nm). Here the aggregation of AuNPs is mediated by balancing aggregation and steric stabilization processes. This is achieved by varying the relative amounts of hydrophobic small molecules, which act as aggregating agents, and end functional hydrophilic polymers that serve as steric stabilizing agents. This approach allows the position of the SPR shifted into the tissue transparency window, while maintaining colloidal stability. Importantly, increased depolarized scattering and surface enhanced Raman scattering (SERS) cross sections in this region are achieved compared to the single nanoparticles. By varying the structure of the aggregating agent slightly, the SERS spectra exhibit significant changes, thus demonstrating the potential to encode different aggregates. The aggregates have potential applications in biomedical imaging, as an encoding strategy for combinatorial chemistry, and for use in flow cytometry applications

Interactions of iodoperfluorobenzene compounds with gold nanoparticles

Understanding the interactions of small molecules with gold nanoparticles is important for controlling their surface chemistry and, hence, how they can be used in specific applications. The interaction of iodoperfluorobenzene compounds with gold nanoparticles was investigated by UV-Vis difference spectroscopy, surface enhanced Raman spectroscopy (SERS) and Synchrotron X-ray photoelectron spectroscopy (XPS). Results from UV-Vis difference spectroscopy demonstrated that iodoperfluorobenzene compounds undergo charge transfer complexation with gold nanoparticles. SERS of the small molecule-gold nanoparticle adducts provided further evidence for formation of charge transfer complexes, while Synchrotron X-ray photoelectron spectroscopy provided evidence of the binding mechanism. Demonstration of interactions of iodoperfluorobenzene compounds with gold nanoparticles further expands the molecular toolbox that is available for functionalising gold nanoparticles and has significant potential for expanding the scope for generation of hybrid halogen bonded materials

Hinged bis-porphyrin scaffolds I: The synthesis of a new porphyrin diene and its role in constructing hinged porphyrin dyads and cavity systems

Norbornene building BLOCKs formed by the reaction of porphyrin 1,3-dienes with norbornadiene or dimethyl tricyclo[4.2.1.02,5]nona-2,7-diene-3,4-dicarboxylate were coupled with an ester-activated cyclobutene epoxide BLOCK to afford the first examples of hinged porphyrin-spacer-acceptor dyads. Similar dual coupling with a bis-(cyclobutene epoxide) formed doubly hinged POR-spacer-POR scaffolds separated by up to 16σ-bonds. The ability of the doubly hinged ZnPOR-16σ-ZnPOR scaffold to adopt cavity-shaped conformations was indicated by semiempirical AM1 calculations of these conformationally flexible bis-porphyrin scaffolds

Hinged bis-porphyrin scaffolds I. The synthesis of a new porphyrin diene and its role in constructing hinged porphyrin dyads and cavity systems

Norbornene building BLOCKs formed by the reaction of porphyrin 1,3-dienes with norbornadiene or dimethyl tricyclo[4.2.1.0(2,5)]nona-2,7-diene-3,4-dicarboxylate were coupled with an ester-activated cyclobutene epoxide BLOCK to afford the first examples of hinged porphyrin-spacer-acceptor dyads. Similar dual coupling with a bis-(cyclobutene epoxide) formed doubly hinged POR-spacer-POR scaffolds separated by up to 16 sigma-bonds. The ability of the doubly hinged ZnPOR-16 sigma-ZnPOR scaffold to adopt cavity-shaped conformations was indicated by semiempirical AM1 calculations of these conformationally flexible bis-porphyrin scaffolds. (C) 2008 Elsevier Ltd. All rights reserved