4582 research outputs found
Sort by
The relationship between single nucleotide polymorphisms of the NTRK2 gene and sporadic Alzheimer's disease in the Chinese Han population
No full textAlzheimer's disease (AD) is characterized by the degeneration of basal forebrain cholinergic neurons, whose survival and function are affected by neurotrophins and their receptors. The impaired signaling pathway of brain-derived neurotrophic factor/tropomyosin-related kinase B (BDNF/TrkB) is considered to play an important role in AD pathogenesis. To explore the association of polymorphisms within the NTRK2 gene (encoding TrkB) and sporadic AD (sAD), a case–control study was conducted in a Chinese Han cohort including 216 sAD patients and 244 control participants. Five single nucleotide polymorphisms (SNPs), with four of them within the promoter region and one in intron, were selected and genotyped with a polymerase chain reaction-ligase detection reaction (PCR-LDR) method. No association was revealed between these SNPs or the haplotypes containing four promoter SNPs and the risk of sAD. The results of this study indicate that polymorphisms in the selected regions of the NTRK2 gene are unlikely to confer the susceptibility of sAD in the Chinese Han population.
Using capacitive deionisation for inland brackish groundwater desalination in a remote location
No full textMineralogical characterisation of Indonesian laterites prior to and post atmospheric leaching
No full textThe limonite ore was found to contain Ni (1.2 wt.%) predominantly within Fe oxy/hydroxides, serpentine and phyllomanganate whilst in the residue Ni (0.4 wt.%) is present in highly crystalline leach resistant minerals, such as spinels. The majority of the Ni (1.6 wt.%) in the saprolite ore was present in serpentine with a small fraction also present in phyllomanganate. This association is further confirmed by the similar saprolite leach extraction curves of Ni and Mg. Goethite and jarosite are both found to be concentrated in the saprolite residue, as is consistent with the decrease in Fe extraction during the saprolite leach. For the final 11 h residue of the saprolite leach, the Ni (0.3 wt.%) is mainly present in undissolved lizardite and leach resistant pyroxene and spinel minerals.
Nanoporous anodic aluminium oxide: Advances in surface engineering and emerging applications
No full textAnodic aluminium oxide (AAO) has been investigated and utilized in numerous products for almost a century. But the rapidly increasing interest in nanoscale materials and their outstanding properties has propelled nanoporous AAO to the fore as one of the most popular nanomaterial with applications across a gamut of areas including molecular separation, catalysis, energy generation and storage, electronics and photonics, sensors and biosensors, drug delivery and template synthesis. Material fabrication of AAO is based on facile and inexpensive electrochemical anodization with the self-ordering process of nanopores not requiring any lithography or templating, and the outcome of the process are perfectly ordered and size controlled nanopores with distinctive pore geometries. Recent research on AAO is characterized by a remarkable trajectory of innovation, in particular with regards to control of surface functionality and, concomitantly, to the design of intricate structural features such as modulated, branched, and multilayered pore architectures. This review illuminates research on recent development of AAO focussing on surface and structural engineering, and on emerging applications. Key examples and critical preparative issues and resulting improvements sparking opportunities for further applications in AAO properties are discussed. We conclude this review with an outlook providing a critical perspective on future trends on surface and structural engineering of AAO.
The effect of impurities and cleavage characteristics on talc hydrophobicity and polymer adsorption
No full textWe have investigated three natural talc samples from different geographical locations (Rhode Island (USA), Delaware (USA), and Flinders Range (Australia)) to determine the effect of impurities and cleavage characteristics on hydrophobicity and polymer adsorption. Bulk (electron microprobe) and surface (X-ray photoelectron spectroscopy) composition measurements have indicated that the Rhode Island and Delaware talcs have the lowest level of Al atoms substituted within the talc structure (0.008%), and detectable at the cleaved basal plane surface (1.5 and 1.7%), and that the Flinders Range talc has the highest level of Al atoms (8.5% bulk; 8.2% surface). Contact angle measurements have highlighted the role of Al atom substitution and step-edge density (as revealed by AFM imaging) on themeasured hydrophobicity of the cleaved surfaces, with the Flinders Range talc and the Rhode Island talc having significantly lower contact angles than the Delaware talc (65° and 83°, respectively, versus 90° for the Delaware). In addition, we have characterised the adsorption of two polysaccharide polymers on the three talc samples (CMC and Dextrin TY) using in situ tapping mode AFM. CMC adsorbs with the same morphology on all three talc samples, whereas Dextrin TY presents three different morphologies on the talc surfaces. The potential implications of the observed variation in adsorption behaviour on mineral flotation are discussed.
Adapting ray tracing to spatial augmented reality
No full textRay tracing is an elegant and intuitive image generation method. The introduction of GPU-accelerated ray tracing and corresponding software frameworks makes this rendering technique a viable option for Augmented Reality applications. Spatial Augmented Reality employs projectors to illuminate physical models and is used in fields that require photorealism, such as design and prototyping. Ray tracing can be used to great effect in this Augmented Reality environment to create scenes of high visual fidelity. However, the peculiarities of SAR systems require that core ray tracing algorithms be adapted to this new rendering environment. This paper highlights the problems involved in using ray tracing in a SAR environment and provides solutions to overcome them. In particular, the following issues are addressed: ray generation, hybrid rendering and view-dependent rendering.
Kinect for interactive AR anatomy learning
No full textEducation of anatomy is a challenging but crucial element in educating medical professionals, but also for general education of pupils. Our research group has previously developed a prototype of an Augmented Reality (AR) magic mirror which allows intuitive visualization of realistic anatomical information on the user. However, the current overlay is imprecise as the magic mirror depends on the skeleton output from Kinect. These imprecisions affect the quality of education and learning. Hence, together with clinicians we have defined bone landmarks which users can touch easily on their body while standing in front of the sensor. We demonstrate that these landmarks allow the proper deformation of medical data within the magic mirror and onto the human body, resulting in a more precise augmentation.
Selection of parameters in active contours for the phenotypic analysis of plants
No full textWe show that over a series of shapes the range of parameters that provide convergence do follow a trend. We also show that not all contours that converge to the objects boundary do so in a stable manner, with a substantial amount oscillating continuously. However more information, such as more shapes and more parameter values, is required to draw meaningful and quantitative conclusions from such an analysis. Future work includes incorporating more of this information along with the application to more active contour models. Another exciting future direction is the use of 2D shape diagrams to quantify relationships between shapes, parameter values and levels of accuracy.