Cognitive evaluation for conceptual design: cognitive role of a 3D sculpture tool in the design thinking process

ABSTRACT

This study focuses on the decisive role played by the digital design environment in the cognitive design process and design thinking. To analyse the cognitive role of digital design tools, we carried out a protocol analysis of conventional design sketching and a 3D sculpture tool. Cognitive evaluation was a differentiating factor when considering the contextual role of the 3D sculpture tool in subsequent evaluations, non-sequential evaluations for conversion, and passive approaches within the design process. Cognitive evaluation played the following roles: validation, extension, navigation, exploration, and confirmation. The navigation, exploration, and extension roles played by non-sequential evaluation were mainly related to inductive design thinking. Finally, the types of cognitive evaluation and their roles when using the 3D sculpture tool were different, according to the design thinking type. This study explored the multidimensional roles of cognitive evaluation using a 3D sculpture tool and its relationship with design thinking types.     

Fabrication and Optical Properties of Periodic Ag Nano‐Pore and Nano‐Particle Arrays with Controlled Shape and Size over Macroscopic Length Scales

A facile and economical route to preparation of highly ordered sliver pore or particle arrays with controlled pore‐shape and size extended over cm² areas is described. The substrates are prepared at planar and curved surfaces via sphere‐imprinted polymer (PDMS) templating using polystyrene spheres with diameters of 820, 600, or 430 nm. Nano‐pore arrays are created by sputtering 80 nm of Ag directly onto the templates and nano‐particle arrays are prepared by electrode‐less deposition of Ag from Tollen's reagent. The shape of the nano‐pore or particles in the array conformed to that of the imprint of the sphere on the template. Stretching the flexible template enable creation of cuboid shaped nano‐voids and nano‐particles following Ag deposition. Diffuse reflectance from the spherical Ag nano‐cavity arrays showed absorbance maxima at wavelengths comparable similar to the diameter of the templating sphere, whereas reflectance from the cuboid arrays, showed little correlation with the sphere diameter. The cuboid nano‐particle arrays showed the most intense visible absorption which is red‐shifted compared to the spherical arrays. White light diffraction from the arrays, observed by rotating 1 cm² substrates relative to a fixed light source, reflected exactly the symmetry axes of the periodic nano‐features in the arrays demonstrating the remarkable macroscopic order of the periodic structures. Raman spectra of 1‐benzenethiol adsorbed at the arrays indicated SERS enhancements from the substrates are attributed mainly to surface nano‐roughness with only moderate contributions from the periodically corrugated structures. Despite excitation at the major resonance dip in the reflectance spectrum, a weak, localized rim dipole mode is found to elicit a small increase in the SERS enhancement factor for the 430 nm diameter spherical arrays. FDTD studies of nano‐void arrays provided insights into v arious factors affecting the SERS experiment and confirmed the array's plasmonic spectra are dominated by propagating plasmon modes under microscope excitation/collection angles.     

Proteomic analysis of integral plasma membrane proteins

Efficient methods for profiling proteins integral to the plasma membrane are highly desirable for the identification of overexpressed proteins in disease cells. Such methods will aid in both understanding basic biological processes and discovering protein targets for the design of therapeutic monoclonal antibodies. Avoiding contamination by subcellular organelles and cytosolic proteins is crucial to the successful proteomic analysis of integral plasma membrane proteins. Here we report a biotin-directed affinity purification (BDAP) method for the preparation of integral plasma membrane proteins, which involves (1) biotinylation of cell surface membrane proteins in viable cells, (2) affinity enrichment using streptavidin beads, and (3) depletion of plasma membrane-associated cytosolic proteins by harsh washes with high-salt and high-pH buffers. The integral plasma membrane proteins are then extracted and subjected to SDS-PAGE separation and HPLC/MS/MS for protein identification. We used the BDAP method to prepare integral plasma membrane proteins from a human lung cancer cell line. Western blotting analysis showed that the preparation was almost completely devoid of actin, a major cytosolic protein. Nano-HPLC/MS/MS analysis of only 30 microg of protein extracted from the affinity-enriched integral plasma membrane preparation led to the identification of 898 unique proteins, of which 781 were annotated with regard to their plasma membrane localization. Among the annotated proteins, at least 526 (67.3%) were integral plasma membrane proteins. Notable among them were 62 prenylated proteins and 45 Ras family proteins. To our knowledge, this is the most comprehensive proteomic analysis of integral plasma membrane proteins in mammalian cells to date. Given the importance of integral membrane proteins for drug design, the described approach will expedite the characterization of plasma membrane subproteomes and the discovery of plasma membrane protein drug targets.     

Automatic heat-shrink sleeve applicator using the low-temperature catalytic combustor

Catalytic combustion for applying heat shrink sleeves (HSS) to a pipeline in KOGAS was investigated. We used a low temperature catalytic combustor in order to place HSS in the conduit. The surface temperature of the catalytic combustor maintained the conditions at which HSS can become well-adhesive at the conduit. Therefore, the automatic HSS construction provided the chance to establish gas pipeline safety by an automatic catalytic combustor device.     

Surface photochemistry: efficient photocatalysis by CdS supported on a solid surface

The photocatalytic efficiency of a series of CdS samples: (i) a colloidal solution in aqueous CH₃CN; (ii) suspensions of (a) supported colloidal particles, (b) bulk CdS, and (c) commercial powders, was compared with respect to stilbenec-t isomerization. The samples of type (ii a), prepared from cadmium chloride and H₂S showed a high photocatalytic activity, attributable to the combined effects of the catalyst particle size and the presence of chloride ions. Increased activity over the commercial sample was also shown in the conversion of hexamethyl(dewar)benzene to hexamethylbenzene, and in the cleavage of anthracene dimer. It has been found that bulk CdS is activated by grinding with < 10% of certain metal chlorides and bromides.     

Variability of the circadian heart rate in diabetes mellitus-related autonomic neuropathy

For assessing the alterations of circadian heart rate variability 66 diabetic patients (age: 52.9 +/- 1.0 years; x +/- SEM) and 23 control subjects (age: 52.7 +/- 1.7 years) were investigated using 24 hours Holter monitoring. Autonomic neuropathy (AN) was evaluated by tests for cardiovascular reflexes and patients were classified as being without AN (n = 26), having mild (n = 25) or definitive (n = 15) signs of AN. Minimal heart rates were significantly higher while maximal heart rates were considerably lower in patients with than without AN (60 +/- 2 min-1 versus 54 +/- 1, min-1, p < 0.05 and 125 +/- 4 min-1 versus 146 +/- 4 min-1, p < 0.01). Diabetic groups were comparable regarding values of averaged heart rates. The difference between the mean waking and sleeping averaged heart rates was the smallest in diabetic patients with definitive signs of AN (9 +/- 2 min-1) differing from those of control subjects (17 +/- 1 min-1, p < 0.01) and diabetic patients without (17 +/- 1 min-1, p < 0.001) or with mild (15 +/- 1 min-1, p < 0.05) signs of AN. Characteristic alteration, i.e. a reduction in circadian heart rate variability could be found in diabetic patients with signs of AN. This phenomenon has primarily been a consequence of more frequent sleeping heart rates due to dominant impairment in cardiac parasympathetic innervation.     

Optimizing aerosolization efficiency of dry-powder aggregates of thermally-sensitive polymeric nanoparticles produced by spray-freeze-drying

Dry powder inhaler (DPI) delivery of therapeutic nanoparticles requires the nanoparticles to be transformed into inhalable micro-scale aggregate structures (i.e. nano-aggregates). The present work details the spray-freeze-drying (SFD) production of dry-powder aggregates of thermally-sensitive polymeric nanoparticles. Specifically, the aim is to optimize the aerosolization efficiency of the nano-aggregates, while keeping the morphology, production yield, flowability, and aqueous reconstitution in the desirable range. For this purpose, the effects of SFD process parameters (i.e. atomization rate, feed concentration, and feed rate) and freeze-drying adjuvant formulation on the nano-aggregate characteristics are examined. Low melting-point poly (caprolactone) (PCL) nanoparticles are used as the model nanoparticles. Mannitol and leucine are used as the hydrophilic and hydrophobic adjuvants, respectively. Large spherical porous nano-aggregates, where PCL nanoparticles are physically dispersed in the porous adjuvant matrix, have been produced. The presence of mannitol is crucial in ensuring that the nano-aggregates readily reconstitute into individual nanoparticles upon exposure to an aqueous environment, so that they can perform their intended therapeutic functions. The presence of leucine, on the other hand, is mandatory to obtain high aerosolization efficiency as its presence reduces the nano-aggregate tendency to agglomerate. At the optimal condition, nano-aggregates exhibiting ED (Emitted Dose) ≈ 95%, FPF (Fine Particle Fraction) ≈ 30%, and MMAD (Mass Median Aerodynamic Diameter) ≈ 5.3 μm, which are comparable to the values obtained in commercial DPI, have been produced. The results signify the potential of SFD to be employed in the production of inhalable dosage form of thermally-sensitive therapeutic nanoparticles.     

Microbiologically influenced corrosion of underground pipelines under the disbonded coatings

The microbiologically influenced corrosion (MIC) of underground pipeline was identified. Corrosion was typically found under the disbonded area of girth welds coating where cathodic protection (CP) current could not penetrate. Sulfate reducing bacteria (SRB) and fermentative acid producing bacteria (APB) were confirmed as the microbes involved in the corrosion process. This corrosion occurred despite the fact that the CP level was well below the criteria of -850 mV (Cu/CuS0₄). Detailed field surveys and laboratory analysis revealed the presence of high numbers of microbes at these sites, metallurgical and mineralogical fingerprints of MIC. The results indicate that the synergistic effects of disbonding, the ineffective input of CP current under the disbonded coatings, and environments favorable to bacterial growth were the corrosion mechanism.