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BCH (Bnip-2 and Cdc42GAP homology) domains are a novel class of protein-interacting domains. First identified in BNIP2 and in Cdc42GAP, a GTPaseactivating-protein (GAP), canonical BCH domains play important and varied roles in the control of cell morphology and apoptosis induction, amongst others. However, this domain is currently classified under lipid-interacting sec14 domains due to low sequence identity (~20%). Given this intriguing similarity, the relationship between BCH and sec14 domains is worth further study. As BCH/sec14 domains are closely associated with cell signaling and human disease, characterization of these domains and the elucidation of their functional diversity could better aid our understanding of their cellular functions and disease pathogenesis.

An exact solution to many current computational problems, such as the famous Travelling Salesman Problem (TSP), require a complete tree traversal in order to determine. This is often unfeasible, as the time complexity of the tree traversal grows exponentially with the size of the input, thus leading to an essentially computationally intractable problem. The branch and bound technique is an approach commonly used to speed this process. It entails dynamically pruning off branches of the tree in which the answer is probably not found in, hence reducing the amount of data that is needed to be traversed and the total time and resources required to perform the computation. In this paper, we introduce a new load-balancing strategy for the execution of such a branch and bound algorithm in parallel, using a three-tiered hierarchical approach, to perform fractal image compression, which is essentially a complete tree traversal problem. This novel heuristic is aimed at achieving optimal load-balancing and minimising unnecessary network traffic and bottlenecking, which functions by predicting the optimum search depth and hence controlling the coarseness of the input that is assigned to each worker node. Our scheme additionally enables us to tailor to the specifications of different clusters, as the heuristic is adjusted based on network speed and processor speed, which vary appreciably from cluster to cluster. We further discuss how to apply our method to other large tree search problems, such as the TSP and other NP-complete problems. We have also enhanced an existing load-balancing strategy outlined in Crivelli et. al. (2004, IBM Journal of Research and Development), by prioritising the reallocation of idle worker nodes such that supervisors who are in need of more help receive a larger share of the free workers.

This project aims to explore the potential of inexpensive in-situ deposition of niobium nitride nanowires to improve electrical conductivity. Transition metal nitrides are well known for attributes such as superconductivity, high melting point, simple structure as well as excellent electrical and thermal conductivities. In particular, niobium nitride possesses exceptional hardness and high reflectivity, as well as being a stable field emitter, making it well suited to applications as a cold cathode material. Niobium nitrides are formed by the uptake of nitrogen by niobium. This is achieved by the exothermic formation of an interstitial solid solution of nitrogen atoms in the bcc lattice of the niobium. Existing research has established the possibility of preparing niobium nitride by heating niobium in nitrogen or ammonia over a range of temperatures, by heating niobium pentaoxide and carbon in the presence of nitrogen as well as by chemical vapor deposition of other niobium compounds, nitrogen or hydrogen. For the purpose of this study, a two-step process was used for synthesis. The benefits of a two-step process over direct ammonolysis are apparent, from the greater degree of freedom pertaining to parameter determination. Additionally, characterization of niobium pentaoxide nanowires synthesize under similar conditions is also made possible by terminating the reaction earlier. NbN nanowires were synthesized by annealing niobium pentaoxide nanowires at 850 oC for 2 hours. Subsequent characterization was done using Raman Spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The presence of NbN nanowires via the conversion of Nb2O5 was ascertained by the absence of sharp peaks at 1000 cm-1 for Raman Spectroscopy and XRD plots. Field emission (FE) properties and electrical properties of NbN nanowires were then measured. NbN nanowires were found to have a high turn-on voltage, stable and relatively good field emission characteristics, demonstrating its potential as a cold cathode material. No current saturation was observed for an applied electric field of 0 to 6.0 V/ μm (5). This suggests a low degree of contact resistance for nanowires produced by this method of annealing, since the passage of electrons is not obstructed. Hence there will only be a small voltage drop between the SiO2 substrate and NbN nanowires. Samples containing NbN nanowires were dislodged by ultrasound to form an aqueous suspension of nanowires. A drop of suspension was dripped onto gold-finger substrates, and current-voltage (I-V) measurements of resultant nanowire bridges were taken. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Nanowire bridges obtained by heat-drying were denser and had better electrical properties than those obtained by evaporation to dryness. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Further work would include varying the cooling processes to observe any changes or deformation. Additionally, niobium nitride nanowires can be hybridized with carbon nanotubes (CNTs). A more in-depth comparison between niobium oxide and niobium nitride nanowires is also proposed, along with exploration of the nitrification of other transition metals.

Introduction The discovery of titania (TiO2) nanotubes suggests vast improvements over extant titania properties. Titania nanotubes are aligned in highly-ordered arrays with a large geometric surface area, making them the ideal material for many applications. However, the mechanism responsible for the growth rates of highly-ordered nanotubes with optimal adhesive properties is not fully explained or understood. Purpose of Research The aims of this project were threefold: to explore the effects of different anodizing parameters on the fabrication of titania nanotubes; to study the photocatalytic activity of the nanotubes; and to deposit gold nanoparticles into the nanotubes. Methodology Nanotube Fabrication: Titanium foil was subjected to potentiostatic anodization with the use of various fluorinebased electrolytes, anodization voltage and duration to compare the effects of different parameters. Scanning electron microscopy (SEM) was used to characterize the nanotube diameter and length of the anodized samples. Photo-electrochemica1 Water-splitting: A PEC cell was assembled using the nanotubes as the photoanode and the samples were anodically polarized in a 1M KOH electrolyte. A potentiostat was employed to control the applied bias and to measure the photocurrent response under light irradiation. Overall photoconversion efficiency (ηc) of the samples was then calculated. Catalyst Support: A gold precursor solution was prepared with HAuC14‧3H2O. Using a novel depositionprecipitation (DP) protocol, gold nanoparticles were deposited on the nanotubes. SEM was used to scan for traces of gold and their locations. Energy-Dispersive X-ray (EDX) spectroscopy was used to confirm the identity of the gold nanoparticles. Data and Discussion Nanotube Fabrication: Preliminary studies found the glycerol/water and glycerol/formamide combinations to be the most promising. In glycerol/water-based electrolytes, higher water content corresponded to a decrease in nanotube length while higher anodization voltage resulted in a significant increase in tube diameter and length. In glycerol/formamide-based electrolytes, higher water content corresponded to a decrease in nanotube diameter while higher fluorine concentration resulted in an increase in inter-tubular spacing. The effects of various fabrication parameters were better understood, contributing to greater control over array dimensions. Photo-electrochemical Water-splitting: A higher anodizaion voltage resulted in a significant improvement in photoconversion efficiency. However, this trend was reversed in chlorine-doped samples, where a longer anodization duration corresponded with better photoconversion efficiency. Doping was found to enhance the photoresponse of the samples, with 6.32 % photoconversion efficiency obtained, suggesting new strategies for light harvesting and a step closer towards commercially-viable solar energy. Catalyst Support: Gold nanoparticles (5-10 nm) were successfully deposited onto the titania nanotube samples. Based on current literature, this was the first successful attempt at depositing gold nanoparticles into titania nanotubes. An EDX spectrum confirmed the identity of the gold nanoparticles. Compared to current catalytic converters, the gold/titania nanotube structure offered a larger catalytic surface area for reactants and the ability to function at low temperatures. Conclusion: By understanding the effects of various parameters on titania nanotube fabrication, the anodization process can be optimized to enable more precise control over array dimensions. High photocatalytic efficiency has also been achieved. In addition, doping is found to improve the photoresponse of titania nanotubes. Gold nanoparticles have been deposited, to our knowledge for the first time, onto the surface and inner walls of titania nanotubes.

The zebrafish (Danio rerio) is a popular model organism used for elucidating complex\r developmental pathways and processes. Although the Zebrafish Genome Project is\r nearing completion, the function of most genes remains to be discovered. In zebrafish,\r where an efficient gene targeting method is still absent, costly Morpholinos (MOs) have\r been widely used to ‘knockdown’ specific genes.

Most neurological diseases are characterized by the presence of protein aggregates,\r suggesting that aberrations in protein homeostasis are associated with neuronal demise. In eukaryotic cells, protein homeostasis is maintained by the chaperone, ubiquitin proteasome (UPS) and autophagy systems. As age is a risk factor for several types of neurodegenerative diseases, the function of these various protein homeostatic systems could become compromised with age. To understand the events that occur during normal aging, we examined the expression of key markers associated with the aforementioned systems in mice aged 1, 3, and >18 months. We found that proteasome activity and the amount of proteasome-related structures remained unaffected with age. Interestingly though, an agerelated increase of a novel Hsp70 chaperone protein species (herein designated Hsp70*) was observed. The expression of Hsp70* is also increased markedly in cells treated with pharmacological agents that promote proteasome inhibition, suggesting a functional interaction between the chaperone system and the UPS. Taken together, our results suggest that there is some form of crosstalk between the chaperone system and the UPS involving the observed HSP70 species.

Chitin, a polysaccharide common in biocomposites, has an interwoven organic framework that can act as a scaffold for mineralization in natural systems. Acidic amino acids, namely aspartic (Asp) and glutamic (Glu) acids, are the primary active molecules at biomineralisation interphases in mollusks and play an important role in controlling the polymorph and morphology of the associated mineral.\r In this study, chitin was extracted from squid pens and used as a scaffold for crystallization. The chitin scaffold was functionalized with glutamic acid and aspartic acid separately to create an artificial microenvironment for the study of biomineralization of calcium carbonate. The objective was to investigate the usefulness of the extracted chitin to serve as a scaffold for calcium carbonate crystallization, especially the fidelity of the polymorph nucleated to the amino acids and proteins used.

Synthesis of halooximes has attracted much attention given their importance as precursors to proline derivatives1, unnatural amino acids2 and a host of alkaloids3. Halooximes have numerous industrial and biological applications 4, for example oxime ethers increases specific channel opening activities, acting as potential targets in drug treatment for various diseases 5, most adrenergic β-receptor blocking compounds also conform to the structure of oxime ethers 6. They also have vitro antifungal activities against certain plants7. A known method for the synthesis of 3 using Me3SiX as a Lewis acid, via intermediate enamines with acyclic/ cyclic bis(oxy)enamines, gives yields between 21-68%. Low yield stems from lack of reaction specificity2. In this work, we investigate coupling nitrogen-oxides with CoBr2 to synthesise halooximes in high yield. Initial cyclic/ acyclic bis(oxy)enamines were prepared by reacting 1 equiv. nitro compound with 2.4 equiv. in excess of dichloromethane under argon atmosphere at a temperature of 0ºC. 2.2 equiv. of TMS-Br was further added and left to stir till thermal equilibrium with room conditions. The cyclic/ acyclic bis(oxy)enamine was isolated upon aqueous work-up, filtration and evaporation. Synthesis of halooximes was carried out by reacting 8mL to 1mmol equiv. of THF and 2 equiv. of CoBr2 under argon atmosphere and left to stir till CoBr2 dissolves. 2mL to 1mmol equiv. of CH2Cl2 was added to 1 equiv. of bis(oxy)enamines. The reaction mixture was left to stir at room temperature for 2 hours, after which aqueous work-up, filtration and evaporation were carried out. Our results are summarized in Table 1. We also obtained relatively high percentage yields for the direct synthesis of bromooximes from cyclic nitronates via a one-pot procedure: Low yield stems from lack of reaction specificity2. In this work, we investigate coupling nitrogen-oxides with CoBr2 to synthesise halooximes in high yield. Initial cyclic/ acyclic bis(oxy)enamines were prepared by reacting 1 equiv. nitro compound with 2.4 equiv. in excess of dichloromethane under argon atmosphere at a temperature of 0ºC. 2.2 equiv. of TMS-Br was further added and left to stir till thermal equilibrium with room conditions. The cyclic/ acyclic bis(oxy)enamine was isolated upon aqueous work-up, filtration and evaporation. Synthesis of halooximes was carried out by reacting 8mL to 1mmol equiv. of THF and 2 equiv. of CoBr2 under argon atmosphere and left to stir till CoBr2 dissolves. 2mL to 1mmol equiv. of CH2Cl2 was added to 1 equiv. of bis(oxy)enamines. The reaction mixture was left to stir at room temperature for 2 hours, after which aqueous work-up, filtration and evaporation were carried out. Our results are summarized in Table 1. We also obtained relatively high percentage yields for the direct synthesis of bromooximes from cyclic nitronates via a one-pot procedure:

CD157 is a 31kDa ectoenzyme that is expressed at elevated levels in patients\r with rheumatoid arthritis (RA). The full function of this protein has yet to be\r determined, and the correlation between CD157 and RA is not well\r understood.