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Item Metadata only 1,2,3-Triazolyl amino acids as AMPA receptor ligands(Pergamon-Elsevier Science Ltd, 2010) Stanley, N.; Pedersen, D.; Nielsen, B.; Kvist, T.; Mathiesen, J.; Brauner-Osborne, H.; Taylor, D.; Abell, A.The central nervous system glutamate receptors are an important target for drug discovery. Herein we report initial investigations into the synthesis and glutamate receptor activity of 1,2,3-triazolyl amino acids. Two compounds were found to be selective AMPA receptor ligands, which warrant further investigation.Item Metadata only 110W 790nm pumped 1908nm thulium fibre laser(IEEE, 2008) Bennetts, S.; Hemming, A.; Davidson, A.; Lancaster, D.; Joint Conference of the Opto-Electronics and Communications Conference and the Australian Conference On Optical Fibre Technology (2008 : Sydney, NSW)We describe the highest power 790nm pumped 1908nm thulium fibre laser reported with an output of 110W and a resolution limited linewidth of 0.5nm.Item Metadata only 12mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources(Blackwell Publishing Ltd, 2011) Nicholas, B.; Rowell, G.; Burton, M.; Walsh, A.; Fukui, Y.; Kawamura, A.; Longmore, S.; Keto, E.We present 12 mm Mopra observations of dense molecular gas towards the W28 supernova remnant (SNR) field. The focus is on the dense molecular gas towards the TeV gamma-ray sources detected by the HESS telescopes, which likely trace the cosmic rays from W28 and possibly other sources in the region. Using the NH3 inversion transitions we reveal several dense cores inside the molecular clouds, the majority of which coincide with high-mass star formation and H ii regions, including the energetic ultracompact H ii region G5.89−0.39. A key exception to this is the cloud north-east of W28, which is well known to be disrupted as evidenced by clusters of 1720 MHz OH masers and broad CO line emission. Here we detect broad NH3, up to the (9,9) transition, with linewidths up to 16 km s−1. This broad NH3 emission spatially matches well with the TeV source HESS J1801−233 and CO emission, and its velocity dispersion distribution suggests external disruption from the W28 SNR direction. Other lines are detected, such as HC3N and HC5N, H2O masers, and many radio recombination lines, all of which are primarily found towards the southern high-mass star formation regions. These observations provide a new view on to the internal structures and dynamics of the dense molecular gas towards the W28 SNR field and, in tandem with future higher-resolution TeV gamma-ray observations, will offer the chance to probe the transport of cosmic rays into molecular clouds.Item Metadata only 2 μm laser characteristics and spectroscopic properties of Yb³⁺/Ho³⁺ co-doped GPGN(OSA/IEEE, 2020) Khalid, M.; Ebendorff-Heidepriem, H.; Lancaster, D.G.; Conference on Lasers and Electro-Optics Pacific Rim (CLEO PR) (3 Aug 2020 - 5 Aug 2020 : virtual online)A new Yb3+/Ho3+ co-doped germanate glass is fabricated and its spectroscopic properties are investigated to present its suitability as a potential gain medium for 2 pm laser operation. Rate equations are further applied to study the 2 pm laser characteristics of the glass pumped at 976 nm. The simulation shows that > 15 % laser slope efficiency can be achieved at 2050 nm by reducing the intracavity losses below 0.5 dB.Item Metadata only 2-nitroveratryl as a photocleavable thiol-protecting group for directed disulfide bond formation in the chemical synthesis of insulin(Wiley-VCH Verlag, 2014) Karas, J.; Scanlon, D.; Forbes, B.; Vetter, I.; Lewis, R.; Gardiner, J.; Separovic, F.; Wade, J.; Hossain, M.Chemical synthesis of peptides can allow the option of sequential formation of multiple cysteines through exploitation of judiciously chosen regioselective thiol-protecting groups. We report the use of 2-nitroveratryl (oNv) as a new orthogonal group that can be cleaved by photolysis under ambient conditions. In combination with complementary S-pyridinesulfenyl activation, disulfide bonds are formed rapidly in situ. The preparation of Fmoc-Cys(oNv)-OH is described together with its use for the solid-phase synthesis of complex cystine-rich peptides, such as insulin.Item Metadata only 2.1 μm waveguide laser fabricated by femtosecond laser direct-writing in Ho³⁺, Tm³⁺:ZBLAN glass(Optical Soc Amer, 2012) Lancaster, D.; Gross, S.; Ebendorff-Heidepriem, H.; Fuerbach, A.; Withford, M.; Monro, T.We report the first Ho3+ doped waveguide laser, which was realized by femtosecond direct-writing of a depressed cladding structure into ZBLAN glass. Tm3+ sensitizing allows the 9 mm long Ho3+ gain medium to be conveniently pumped at 790 nm, achieving an optical-to-optical slope efficiency of 20% and a threshold of 20 mW. The potentially widely tunable laser produces up to 76 mW at 2052 nm and also operates at shorter wavelengths near 1880 nm and 1978 nm for certain cavity configurations.Item Metadata only 2D-DIGE analysis of sera from transgenic mouse models reveals novel candidate protein biomarkers for human gastric cancer(Elsevier BV, 2012) Penno, M.; Klingler-Hoffmann, M.; Brazzatti, J.; Boussioutas, A.; Putoczki, T.; Ernst, M.; Hoffmann, P.The gp130(F/F) genetically engineered mouse (GEM) model reproducibly and predictably develops a gastric adenoma phenotype resembling the primary lesions of human intestinal-type gastric cancer (GC). Accordingly, changes to the serum proteome of gp130(F/F) mice may uncover early-stage GC biomarkers. Here, we have employed several double and compound mutant GEM strains that display distinct phenotypes with respect to gastric tumour load and inflammatory response, thereby mimicking different states of inflammation-associated early-stage GC in humans. This allowed us to distinguish between proteomic changes associated with tumourigenesis rather than confounding systemic inflammation. The comparative proteomic workflow involved depletion of high abundance proteins, 2D-DIGE analysis and protein identification by LC-MS/MS. The differential expression of 112 2D-DIGE spots specifically correlated with the tumour-bearing phenotype, corresponding to 31 murine proteins and their 28 human orthologues. Eight proteins were selected for validation in GC patient sera versus healthy controls. Significant increases in serum apolipoprotein E and haptoglobin, and decreases in afamin and clusterin, were confirmed by ELISA. Receiver operating characteristic analysis revealed that these proteins may be more sensitive and specific discriminators of GC than the existing clinical marker CA72-4.Item Open Access 3D dose distribution measurement using 2D imaging from NaCl optical crystals(IOP Publishing, 2020) Chapsky, A.; Spooner, N.A.; Santos, A.; Rutten, T.; Micro-Mini & Nano Dosimetry and Innovative Technologies in Radiation Oncology (MMND ITRO) (10 Feb 2020 - 16 Feb 2020 : Wollongong, Australia)In radiotherapy practice, 1D and 2D dosimeters are used for dose verification prior to patient treatment. Along with high accuracy and precision of dose measurements that these dosimeters provide, acquisition of dose deposition data in three dimensions requires extrapolation of measured data. Development of a 3D dosimeter would provide continuous information of dose distribution in matter. In this work, NaCl 3D crystal has shown that radiation deposition can be imaged using blue laser stimulation in two dimensions. It was further shown that the intensity of collected signal has near – linear dose dependence, however complete signal readout is required, to compensate for gradual signal collection at different depths along the profile of the stimulating laser beam, due to attenuation of the beam within the crystal. A method to extend dose measurement to three dimensions using imaging is proposed.Item Metadata only 3D glass printing for fibre preforms(2022) Radionova, A.; Australian Institute of Physics Congress (AIP) ANFF Pre Conference Workshop (11 Dec 2022 - 11 Dec 2022 : Adelaide)Item Metadata only 3D printing Bullseye glass preform for fibre drawing(2022) Pan, X.; Denker, M.; Radionova, A.; Wei, Y.; Schartner, E.; Koutsonikolas, T.; Ebendorff-Heidepriem, H.; International Workshop on Speciality Optical Fibres and Their Applications (WSOF) (11 Dec 2022 - 16 Dec 2022 : Adelaide Convention Centre, Adelaide. South Australia)Item Metadata only 3D-printed extrusion dies: a versatile approach to optical material processing(Optical Society of America, 2014) Ebendorff-Heidepriem, H.; Schuppich, J.; Dowler, A.; Lima-Marques, L.; Monro, T.Abstract not availableItem Metadata only A 4W tunable Tm3+:Ho3+ silica fibre laser(2008) Hemming, A.; Sabella, A.; Bennetts, S.; Jackson, S.; Lancaster, D.; Conference on Lasers and Electro-Optics (2008 : San Jose, California)Item Metadata only 5-Benzylidenerhodanine and 5-benzylidene-2-4-thiazolidinedione based antibacterials(Pergamon-Elsevier Science Ltd, 2012) Zvarec, O.; Polyak, S.; Tieu, W.; Kuan, K.; Dai, H.; Pedersen, D.; Morona, R.; Zhang, L.; Booker, G.; Abell, A.Herein we outline the antibacterial activity of amino acid containing thiazolidinediones and rhodanines against Gram-positive bacteria Staphylococcus aureus ATCC 31890, Staphylococcus epidermidis and Bacillus subtilis ATCC 6633. The rhodanine derivatives were generally more active than the analogous thiazolidinediones. Compounds of series 5 showed some selectivity for Bacillus subtilis ATCC 6633, the extent of which is enhanced by the inclusion of a non-polar amino acid at the 5-position of the core thiazolidinediones and rhodanines scaffolds. SAR data of series 8 demonstrated improved activity against the clinically more significant Staphylococci with selectivity over Bacillus subtilis ATCC 6633 induced by introduction of a bulky aryl substituent at the 5-position of the core scaffolds.Item Metadata only 85 W Tm³⁺-doped silica fibre laser(IET, 2005) Frith, G.; Lancaster, D.; Jackson, S.An 85 W Tm³⁺-doped silica fibre laser is presented. To the best of the authors’ knowledge this is the highest output power achieved by pumping with 793 nm. The slope efficiency was 56%, the threshold 11 Wand the output wavelength centred at 2.04 µm. The high rate of cross relaxation in this laser provided a quantum efficiency of >130%.Item Metadata only 85W Tm³⁺-doped 2μm fibre laser pumped at 793nm.(IEEE, 2005) Frith, G.; Lancaster, D.; Jackson, S.; Lasers and Electro-Optics Society Annual Meeting (2005 : Sydney, NSW)Through diode pumping at 793 nm we have achieved 85 W output from a Tm3+-doped silica fibre laser operating at 2.04 μm. To the best of our knowledge this is the highest output power achieved for pumping at 793 nm. The slope efficiency was 56% giving an overall quantum efficiency of 130%.Item Metadata only A 226W hiqh power tm fibre laser(IEEE, 2008) Hemming, A.; Bennetts, S.; Davidson, A.; Carmody, N.; Lancaster, D.; Joint Conference of the Opto-Electronics and Communications Conference and the Australian Conference On Optical Fibre Technology (2008 : Sydney, NSW)Item Metadata only A 40% slope efficiency 790nm pumped 1.9 micrometre Tm3+: ZBLAN directly-written waveguide laser(IEEE, 2011) Lancaster, D.; Gross, S.; Ebendorff-Heidepriem, H.; Kuan, K.; Monro, T.; Fuerbach, A.; Whitford, M.; CLEO/Europe-EQEC (2011 : Munich, Germany)We report a thulium ZBLAN buried waveguide laser which produces 40mW at 1880nm and has a measured M^2 of 1.6. The waveguide structure is a depressed cladding written using a direct-write fs laser.Item Metadata only A 7 mm line survey of the shocked and disrupted molecular gas towards the W28 field TeV gamma-ray sources(Blackwell Publishing Ltd, 2012) Nicholas, B.; Rowell, G.; Burton, M.; Walsh, A.; Fukui, Y.; Kawamura, A.; Maxted, N.We present 7 mm Mopra observations of the dense molecular gas towards the W28 supernova remnant (SNR) field, following a previous 12 mm line survey of this region. These observations take advantage of the 7 mm beam size to probe the dense and disrupted gas in the region at ∼1 arcmin scales. Our observations are focused towards the north-eastern (NE) HESS J1801−233 and southern HESS J1800−240 B TeV gamma-ray sources, with slightly less observations towards HESS J1800−240 A and C. Using the CS (1–0) transition we reveal multiple regions of dense gas, cm−3. We report the discovery of dense gas towards HESS J1800−240 C, at the site of a 1720 MHz OH maser. The NE molecular cloud is known to be disrupted; many 1720 MHz OH masers and broad CO line emission are detected at the rim of W28. Here, we reveal this shock interaction region contains generally extended clumpy CS, as well as clumpy SiO and CH3OH emission with broad line profiles. The full width at half maximum (FWHM) of the molecular lines extend up to 18 km s−1 on the W28 side of the NE cloud. The detection of SiO towards maser clumps OH C, D, E and F provides further evidence of the shocked conditions in the NE cloud. Several other lines associated with star formation are also detected towards the southern source, notably the energetic H ii complex G5.89−0.39. The spatial match of dense gas with the TeV emission further supports the cosmic ray (CR) origin for the gamma-rays. We estimate the mass of several extended dense clouds within the field and predict the TeV flux from the dense cloud components. The predicted fluxes are of the order of 10−14 to 10−13 photons cm−2 s−1, which should be detectable and possibly resolved by a future TeV instrument, such as the Cherenkov Telescope Array.Item Metadata only A bright, pulsed, guide star laser for very large telescopes(SPIE, 2010) Munch, J.; Hamilton, M.; Hosken, D.; Simakov, N.; Veitch, P.; Adaptive Optics Systems II (2010 : San Diego, USA); Ellerbroek, B.L.; Hart, M.; Hubin, N.; Wizinowich, P.L.We demonstrate for the first time the practical feasibility of a new sodium guide star laser with a pulsed burst output of sufficient energy at 589nm to be useful for current applications and readily scalable to meet future requirements. We describe complete experimental design verification results of the pulse burst laser concept, optimized to eliminate guide-star elongation issues and to meet all requirements for Multi Conjugate Adaptive Optics (MCAO) for future extremely large ground-based telescopes (ELTs). It makes use of sum frequency generation (SFG) of two, Q-switched, injection mode-locked, wavelength stabilized Nd:YAG lasers, producing a macro-micro, pulse-burst output which is optimized in power and bandwidth to maximize the fluorescence from the high altitude sodium layer. © 2010 SPIE.Item Metadata only A carbon-nanofiber glass composite with high electrical conductivity(Wiley, 2020) Tao, G.; Chen, S.; Pandey, S.J.; Tan, F.A.; Ebendorff-Heidepriem, H.; Molinari, M.; Abouraddy, A.F.; Gaume, R.M.The use of oxide glasses is pervasive throughout everyday amenities and commodities. Such glasses are typically electrical insulators, and endowing them with electrical conductivity—without changing their salutary mechanical properties, weight, or thermoformability—enables new applications in multifunctional utensils, smart windows, and automotive parts. Previous strategies to impart electrical conductivity include modifying the glass composition or forming a solid‐in‐solid composite of the glass and a conductive phase. Here, we demonstrate—using the latter strategy—the highest reported room‐temperature electrical conductivity in a bulk oxide glass (~1800 S/m) corresponding to the theoretical limit for the loading fraction of the conductive phase. This is achieved through glass sintering of a mixture of carbon nanofibers (CNFs) and oxide flint (F2) or soda‐lime glasses, with the bulk conductivity further enhanced by a polyethylene‐block‐poly(ethylene glycol) additive. A theoretical model provides predictions that are in excellent agreement with the dependence of conductivity of these composites on the carbon‐loading fraction. Moreover, nanoscale electrical characterization of the composite samples provides evidence for the existence of a connected network of CNFs throughout the bulk. Our results establish a potentially low‐cost approach for producing large volumes of highly conductive glass independently of the glass composition.