47 results on '"Nightingale, James"'
Search Results
2. COSMOS-Web: An Overview of the JWST Cosmic Origins Survey
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Casey, Caitlin M, Kartaltepe, Jeyhan S, Drakos, Nicole E, Franco, Maximilien, Harish, Santosh, Paquereau, Louise, Ilbert, Olivier, Rose, Caitlin, Cox, Isabella G, Nightingale, James W, Robertson, Brant E, Silverman, John D, Koekemoer, Anton M, Massey, Richard, McCracken, Henry Joy, Rhodes, Jason, Akins, Hollis B, Allen, Natalie, Amvrosiadis, Aristeidis, Arango-Toro, Rafael C, Bagley, Micaela B, Bongiorno, Angela, Capak, Peter L, Champagne, Jaclyn B, Chartab, Nima, Ortiz, Óscar A Chávez, Chworowsky, Katherine, Cooke, Kevin C, Cooper, Olivia R, Darvish, Behnam, Ding, Xuheng, Faisst, Andreas L, Finkelstein, Steven L, Fujimoto, Seiji, Gentile, Fabrizio, Gillman, Steven, Gould, Katriona ML, Gozaliasl, Ghassem, Hayward, Christopher C, He, Qiuhan, Hemmati, Shoubaneh, Hirschmann, Michaela, Jahnke, Knud, Jin, Shuowen, Khostovan, Ali Ahmad, Kokorev, Vasily, Lambrides, Erini, Laigle, Clotilde, Larson, Rebecca L, Leung, Gene CK, Liu, Daizhong, Liaudat, Tobias, Long, Arianna S, Magdis, Georgios, Mahler, Guillaume, Mainieri, Vincenzo, Manning, Sinclaire M, Maraston, Claudia, Martin, Crystal L, McCleary, Jacqueline E, McKinney, Jed, McPartland, Conor JR, Mobasher, Bahram, Pattnaik, Rohan, Renzini, Alvio, Rich, R Michael, Sanders, David B, Sattari, Zahra, Scognamiglio, Diana, Scoville, Nick, Sheth, Kartik, Shuntov, Marko, Sparre, Martin, Suzuki, Tomoko L, Talia, Margherita, Toft, Sune, Trakhtenbrot, Benny, Urry, C Megan, Valentino, Francesco, Vanderhoof, Brittany N, Vardoulaki, Eleni, Weaver, John R, Whitaker, Katherine E, Wilkins, Stephen M, Yang, Lilan, and Zavala, Jorge A
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Astronomical Sciences ,Physical Sciences ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Physical Chemistry (incl. Structural) ,Astronomy & Astrophysics ,Astronomical sciences ,Particle and high energy physics ,Space sciences - Abstract
Abstract: We present the survey design, implementation, and outlook for COSMOS-Web, a 255 hr treasury program conducted by the James Webb Space Telescope in its first cycle of observations. COSMOS-Web is a contiguous 0.54 deg2 NIRCam imaging survey in four filters (F115W, F150W, F277W, and F444W) that will reach 5σ point-source depths ranging ∼27.5–28.2 mag. In parallel, we will obtain 0.19 deg2 of MIRI imaging in one filter (F770W) reaching 5σ point-source depths of ∼25.3–26.0 mag. COSMOS-Web will build on the rich heritage of multiwavelength observations and data products available in the COSMOS field. The design of COSMOS-Web is motivated by three primary science goals: (1) to discover thousands of galaxies in the Epoch of Reionization (6 ≲ z ≲ 11) and map reionization’s spatial distribution, environments, and drivers on scales sufficiently large to mitigate cosmic variance, (2) to identify hundreds of rare quiescent galaxies at z > 4 and place constraints on the formation of the universe’s most-massive galaxies (M ⋆ > 1010 M ⊙), and (3) directly measure the evolution of the stellar-mass-to-halo-mass relation using weak gravitational lensing out to z ∼ 2.5 and measure its variance with galaxies’ star formation histories and morphologies. In addition, we anticipate COSMOS-Web’s legacy value to reach far beyond these scientific goals, touching many other areas of astrophysics, such as the identification of the first direct collapse black hole candidates, ultracool subdwarf stars in the Galactic halo, and possibly the identification of z > 10 pair-instability supernovae. In this paper we provide an overview of the survey’s key measurements, specifications, goals, and prospects for new discovery.
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- 2023
3. Consumption prediction with privacy concern: Application and evaluation of Federated Learning
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Wang, Yingjie, Zobiri, Fairouz, Mustafa, Mustafa A., Nightingale, James, and Deconinck, Geert
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- 2024
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4. Unveiling lens light complexity with a novel multi-Gaussian expansion approach for strong gravitational lensing.
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He, Qiuhan, Nightingale, James W, Amvrosiadis, Aris, Robertson, Andrew, Cole, Shaun, Frenk, Carlos S, Massey, Richard, Li, Ran, Cao, Xiaoyue, Lange, Samuel C, and França, João Paulo C
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GRAVITATIONAL lenses , *GALACTIC magnitudes , *IMAGE processing - Abstract
In a strong gravitational lensing system, the distorted light from a source is analysed to infer the properties of the lens. However, light emitted by the lens itself can contaminate the image of the source, introducing systematic errors in the analysis. We present a simple and efficient lens light model based on the well-tested multi-Gaussian expansion (MGE) method for representing galaxy surface brightness profiles, which we combine with a semi-linear inversion scheme for pixelized source modelling. Testing it against realistic mock lensing images, we show that our scheme can fit the lensed images to the noise level, with relative differences between the true input and best-fitting lens light model remaining below 5 per cent. We apply the MGE lens light model to 38 lenses from the HST SLACS sample. We find that the new scheme provides a good fit for the majority of the sample with only 3 exceptions – these show clear asymmetric residuals in the lens light. We examine the radial dependence of the ellipticity and position angles and confirm that it is common for a typical lens galaxy to exhibit twisting non-elliptical isophotes and boxy / disky isophotes. Our MGE lens light model will be a valuable tool for understanding the hidden complexity of the lens mass distribution. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Strong gravitational lensing's 'external shear' is not shear.
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Etherington, Amy, Nightingale, James W, Massey, Richard, Tam, Sut-Ieng, Cao, XiaoYue, Niemiec, Anna, He, Qiuhan, Robertson, Andrew, Li, Ran, Amvrosiadis, Aristeidis, Cole, Shaun, Diego, Jose M, Frenk, Carlos S, Frye, Brenda L, Harvey, David, Jauzac, Mathilde, Koekemoer, Anton M, Lagattuta, David J, Lange, Samuel, and Limousin, Marceau
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GRAVITATIONAL lenses , *GALACTIC evolution , *PHYSICAL cosmology , *SPACE telescopes , *DARK matter , *GALAXY formation , *GALAXIES - Abstract
The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus 'external shear', which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight. A small amount of external shear could come from these sources, but we show that the vast majority does not. Except in a handful of rare systems, the best-fitting values do not correlate with independent measurements of line-of-sight shear: from weak lensing in 45 Hubble Space Telescope images, or in 50 mock images of lenses with complex distributions of mass. Instead, the best-fit external shear is aligned with the major or minor axis of 88 per cent of lens galaxies; and the amplitude of the external shear increases if that galaxy is discy. We conclude that 'external shear' attached to a power-law model is not physically meaningful, but a fudge to compensate for lack of model complexity. Since it biases other model parameters that are interpreted as physically meaningful in several science analyses (e.g. measuring galaxy evolution, dark matter physics or cosmological parameters), we recommend that future studies of galaxy-scale strong lensing should employ more flexible mass models. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Adenoid cystic carcinoma: a review of clinical features, treatment targets and advances in improving the immune response to monoclonal antibody therapy
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Nightingale, James, Lum, Benedict, Ladwa, Rahul, Simpson, Fiona, and Panizza, Benedict
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- 2021
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7. Scanning for dark matter subhaloes in Hubble Space Telescope imaging of 54 strong lenses.
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Nightingale, James W, He, Qiuhan, Cao, Xiaoyue, Amvrosiadis, Aristeidis, Etherington, Amy, Frenk, Carlos S, Hayes, Richard G, Robertson, Andrew, Cole, Shaun, Lange, Samuel, Li, Ran, and Massey, Richard
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SPACE telescopes , *DARK matter , *GRAVITATIONAL lenses , *DEGREES of freedom , *GALAXIES - Abstract
The cold dark matter (DM) model predicts that every galaxy contains thousands of DM subhaloes; almost all other DM models include a physical process that smooths away the subhaloes. The subhaloes are invisible, but could be detected via strong gravitational lensing, if they lie on the line of sight to a multiply imaged background source, and perturb its apparent shape. We present a predominantly automated strong lens analysis framework, and scan for DM subhaloes in Hubble Space Telescope imaging of 54 strong lenses. We identify five DM subhalo candidates, including two especially compelling candidates (one previously known in SLACS0946 + 1006) where a subhalo is favoured after all of our tests for systematics. We find that the detectability of subhaloes depends upon the assumed parametric form for the lens galaxy's mass distribution, especially its degree of azimuthal freedom. Using separate components for DM and stellar mass reveals two DM subhalo candidates and removes four false positives compared to the single power-law mass model that is common in the literature. We identify 45 lenses without substructures, the number of which is key to statistical tests able to rule out models of, for example, warm or self-interacting DM. Our full analysis results are available at https://github.com/Jammy2211/autolens_subhalo. [ABSTRACT FROM AUTHOR]
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- 2024
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8. 5G-UHD: Design, prototyping and empirical evaluation of adaptive Ultra-High-Definition video streaming based on scalable H.265 in virtualised 5G networks
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Salva-Garcia, Pablo, Alcaraz-Calero, Jose M., Alaez, Ricardo Marco, Chirivella-Perez, Enrique, Nightingale, James, and Wang, Qi
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- 2018
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9. Future mode of operations for 5G – The SELFNET approach enabled by SDN/NFV
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Neves, Pedro, Calé, Rui, Costa, Mário, Gaspar, Gonçalo, Alcaraz-Calero, Jose, Wang, Qi, Nightingale, James, Bernini, Giacomo, Carrozzo, Gino, Valdivieso, Ángel, García Villalba, Luis Javier, Barros, Maria, Gravas, Anastasius, Santos, José, Maia, Ricardo, and Preto, Ricardo
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- 2017
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10. Discovery of a radio jet in the Cloverleaf quasar at z = 2.56.
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Zhang, Lei, Zhang, Zhi-Yu, Nightingale, James W, Zou, Ze-Cheng, Cao, Xiaoyue, Tsai, Chao-Wei, Yang, Chentao, Shi, Yong, Wang, Junzhi, Xu, Dandan, Lin, Ling-Rui, Zhou, Jing, and Li, Ran
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QUASARS ,ACTIVE galactic nuclei ,GALACTIC evolution ,SUPERMASSIVE black holes ,GRAVITATIONAL lenses - Abstract
The fast growth of supermassive black holes and their feedback to the host galaxies play an important role in regulating the evolution of galaxies, especially in the early Universe. However, due to cosmological dimming and the limited angular resolution of most observations, it is difficult to resolve the feedback from the active galactic nuclei (AGNs) to their host galaxies. Gravitational lensing, for its magnification, provides a powerful tool to spatially differentiate emission originating from AGN and host galaxy at high-redshifts. Here, we report a discovery of a jet-like radio structure in a strongly lensed starburst quasar, H1413+117 or Cloverleaf at redshift z = 2.56, based on observational data at optical, submillimetre, and radio wavelengths. With both parametric and non-parametric lens models and with reconstructed images in the source plane, we find a well-separated, kpc-scaled, single-sided radio jet located at projected |${\sim }1.2\, \mathrm{kpc}$| to the north-west of the host galaxy in the source plane. This could indicate the co-existence of feedback from the AGN by both wind and jet in the Cloverleaf quasar. [ABSTRACT FROM AUTHOR]
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- 2023
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11. Special issue on multimedia fog/edge computing systems
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Jin, Yong, D’Agostino, Daniele, Achir, Nadjib, Nightingale, James, and Wang, Jiacun
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- 2020
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12. Beyond the bulge–halo conspiracy? Density profiles of early-type galaxies from extended-source strong lensing.
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Etherington, Amy, Nightingale, James W, Massey, Richard, Robertson, Andrew, Cao, XiaoYue, Amvrosiadis, Aristeidis, Cole, Shaun, Frenk, Carlos S, He, Qiuhan, Lagattuta, David J, Lange, Samuel, and Li, Ran
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GALAXIES , *STELLAR dynamics , *DARK matter , *SPACE telescopes , *STATISTICAL power analysis - Abstract
Observations suggest that the dark matter and stars in early-type galaxies 'conspire' to produce a surprisingly simple distribution of total mass, ρ(r) ∝ ρ−γ, with γ ≈ 2. We measure the distribution of mass in 48 early-type galaxies that gravitationally lens a resolved background source. By fitting the source light in every pixel of images from the Hubble Space Telescope , we find a mean |$\langle \gamma \rangle =2.075_{-0.024}^{+0.023}$| with an intrinsic scatter between galaxies of |$\sigma _\gamma =0.172^{+0.022}_{-0.032}$| for the overall sample. This is consistent with and has similar precision to traditional techniques that employ spectroscopic observations to supplement lensing with mass estimates from stellar dynamics. Comparing measurements of γ for individual lenses using both techniques, we find a statistically insignificant correlation of |$-0.150^{+0.223}_{-0.217}$| between the two, indicating a lack of statistical power or deviations from a power-law density in certain lenses. At fixed surface mass density, we measure a redshift dependence, |$\partial \langle \gamma \rangle /\partial z=0.345^{+0.322}_{-0.296}$| , that is consistent with traditional techniques for the same sample of Sloan Lens ACS and GALaxy-Lyα EmitteR sYstems (GALLERY) lenses. Interestingly, the consistency breaks down when we measure the dependence of γ on the surface mass density of a lens galaxy. We argue that this is tentative evidence for an inflection point in the total mass-density profile at a few times the galaxy effective radius – breaking the conspiracy. [ABSTRACT FROM AUTHOR]
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- 2023
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13. Testing strong lensing subhalo detection with a cosmological simulation.
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He, Qiuhan, Nightingale, James, Robertson, Andrew, Amvrosiadis, Aristeidis, Cole, Shaun, Frenk, Carlos S, Massey, Richard, Li, Ran, Amorisco, Nicola C, Metcalf, R Benton, Cao, Xiaoyue, and Etherington, Amy
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GRAVITATIONAL lenses , *HYPERGEOMETRIC series , *DARK matter , *GAUSSIAN distribution , *GALACTIC halos , *GALAXIES , *GALAXY clusters - Abstract
Strong gravitational lensing offers a compelling test of the cold dark matter paradigm, as it allows for subhaloes with masses of ∼109 M⊙ and below to be detected. We test commonly used techniques for detecting subhaloes superposed in images of strongly lensed galaxies. For the lens we take a simulated galaxy in a ∼1013 M⊙ halo grown in a high-resolution cosmological hydrodynamical simulation, which we view from two different directions. Though the resolution is high, we note the simulated galaxy still has an artificial core which adds additional complexity to the baryon dominated region. To remove particle noise, we represent the projected galaxy mass distribution by a series of Gaussian profiles which precisely capture the features of the projected galaxy. We first model the lens mass as a (broken) power-law density profile and then search for small haloes. Of the two projections, one has a regular elliptical shape, while the other has distinct deviations from an elliptical shape. For the former, the broken power-law model gives no false positives and correctly recovers the mass of the superposed small halo; however, for the latter we find false positives and the inferred halo mass is overestimated by ∼4–5 times. We then use a more complex model in which the lens mass is decomposed into stellar and dark matter components. In this case, we show that we can capture the simulated galaxy's complex projected structures and correctly infer the input small halo. [ABSTRACT FROM AUTHOR]
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- 2023
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14. The "External" Shears In Strong Lens Models.
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Nightingale, James W., Etherington, Amy, and Massey, Richard
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GRAVITATIONAL lenses , *DARK matter , *GALAXIES , *PHYSICAL cosmology - Abstract
The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power law plus 'external shear', which notionally accounts for line-of-sight galaxies and cosmic shear. We argue that it does not, using three lines of evidence from the analysis of 54 galaxy-scale strong lenses: (i) strong lensing external shears do not correlate with weak lensing; (ii) the measured shear magnitudes in strong lenses (which are field galaxies) are too large (exceeding 0.05) for their environment and; (iii) the external shear position angle preferentially aligns or anti-aligns with the mass model position angle, indicating an internal origin. We argue the measured strong lensing shears are therefore systematically accounting for missing complexity in the canonical elliptical power-law mass model. If we can introduce this complexity into our lens models, this will further lensing studies of galaxy formation, dark matter and Cosmology. [ABSTRACT FROM AUTHOR]
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- 2022
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15. The last stand before Rubin: semi-automated inverse modelling of galaxy-galaxy strong lensing systems.
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França, João Paulo C., Makler, Martin, Beloto, Ingrid, Cypriano, Eduardo, Oliveira, Renan A., Gonçalves, Thiago S., and Nightingale, James
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GENERAL relativity (Physics) ,OBSERVATORIES ,GRAVITATIONAL lenses ,SAMPLE size (Statistics) ,TELESCOPES - Abstract
Galaxy-galaxy strong lensing (SL) systems provide a unique opportunity to test modified gravity theories. Deviations from General Relativity are encoded in the post-Newtonian parameter (γ). As a preparation for the upcoming data from the Vera Rubin Observatory Legacy Survey of Space and Time (LSST), our research group collected imaging data of SL systems from ground-based telescopes and conducted spectroscopic observations of 21 systems on the Southern Astrophysical Research (SOAR) Telescope to measure the lens velocity dispersions, σ
v . We briefly describe the semi-automated SL modelling of the systems in this sample and combine the results with σv from SOAR to derive an estimate for γ. Our preliminary results yield a value of $$\gamma = 1.17_{ - 0.33}^{ + 0.29}$$ , which is consistent with General Relativity. Although the error bars are limited by the sample size, this result represents the first constraint on modified gravity obtained purely from ground-based data, with a sample completely independent from previous studies, and which allows for a self consistent end-to-end analysis. [ABSTRACT FROM AUTHOR]- Published
- 2022
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16. Empirical evaluation of H.264/SVC streaming in resource-constrained multihomed mobile networks
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Nightingale, James, Wang, Qi, and Grecos, Christos
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- 2014
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17. Galaxy–galaxy strong lens perturbations: line-of-sight haloes versus lens subhaloes.
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He, Qiuhan, Li, Ran, Frenk, Carlos S, Nightingale, James, Cole, Shaun, Amorisco, Nicola C, Massey, Richard, Robertson, Andrew, Etherington, Amy, Amvrosiadis, Aristeidis, and Cao, Xiaoyue
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CONFIGURATIONS (Geometry) ,DETECTION limit ,GRAVITATIONAL lenses ,DARK matter - Abstract
We rederive the number density of intervening line-of-sight haloes relative to lens subhaloes in galaxy-galaxy strong lensing observations, where these perturbers can generate detectable image fluctuations. Previous studies have calculated the detection limit of a line-of-sight small-mass dark halo by comparing the lensing deflection angles it would cause, to those caused by a subhalo within the lens. However, this overly simplifies the difference in observational consequences between a subhalo and a line-of-sight halo. Furthermore, it does not take into account degeneracies between an extra subhalo and the uncertain properties of the main lens. More in keeping with analyses of real-world observations, we regard a line-of-sight halo as detectable only if adding it to a smooth model generates a statistically significant improvement in the reconstructed image. We find that the number density of detectable line-of-sight perturbers has been overestimated by as much as a factor of two in the previous literature. For typical lensing geometries and configurations, very deep imaging is sensitive to twice as many line-of-sight perturbers as subhaloes, but moderate depth imaging is sensitive to only slightly more line-of-sight perturbers than subhaloes. [ABSTRACT FROM AUTHOR]
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- 2022
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18. Utility of Hydroxypropylmethylcellulose Acetate Succinate (HPMCAS) for Initiation and Maintenance of Drug Supersaturation in the GI Milieu
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Curatolo, William, Nightingale, James A., and Herbig, Scott M.
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- 2009
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19. Immunotherapy for the treatment of perineural spread in cutaneous head and neck squamous cell carcinoma: Time to rethink treatment paradigms.
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Nightingale, James, Gandhi, Mitesh, Helena, Jonathan, Bowman, James, McGrath, Margaret, Coward, Jermaine, Porceddu, Sandro, Ladwa, Rahul, and Panizza, Benedict
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SQUAMOUS cell carcinoma ,POSITRON emission tomography ,IMMUNE checkpoint inhibitors ,MAGNETIC resonance imaging ,HEAD & neck cancer ,IMMUNOTHERAPY - Abstract
Background: Immune checkpoint inhibitors have shown promising antitumour activity. Application in head and neck cutaneous squamous cell carcinoma (cSCC) large nerve perineural spread (PNS) is limited. Methods: Retrospective review of 13 patients with PNS receiving anti‐PD‐1 therapy from September 2017 to May 2021 is presented. Primary endpoints were objective response (complete or partial response) and median time to progression, determined by Head and Neck Multi‐Disciplinary Team (MDT) and independent radiology review of magnetic resonance imaging (MRI) and/or computed tomography/positron emission tomography (CT/PET). Results: Objective response was observed in 9/13 patients (69%), with complete response in 6 (46%) and partial response in 3 patients (23%). Median time to response was 2.1 months (IQR 1.8–2.7 months). There were 3 (23%) patients with progressive disease, with median time to progression of 3.5 months. There were no grade 3–4 treatment related adverse events. Conclusions: This case series supports developing evidence for anti‐PD‐1 checkpoint inhibitor therapy for perineural spread, supporting future prospective clinical trials in this patient population. [ABSTRACT FROM AUTHOR]
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- 2022
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20. forward-modelling method to infer the dark matter particle mass from strong gravitational lenses.
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He, Qiuhan, Robertson, Andrew, Nightingale, James, Cole, Shaun, Frenk, Carlos S, Massey, Richard, Amvrosiadis, Aristeidis, Li, Ran, Cao, Xiaoyue, and Etherington, Amy
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DARK matter ,SPACE telescopes ,SIGNAL-to-noise ratio ,COSMOGONY ,SPATIAL resolution ,GRAVITATIONAL lenses - Abstract
A fundamental prediction of the cold dark matter (CDM) model of structure formation is the existence of a vast population of dark matter haloes extending to subsolar masses. By contrast, other dark matter models, such as a warm thermal relic (WDM), predict a cutoff in the mass function at a mass which, for popular models, lies approximately between 10
7 and |$10^{10}\, {\rm M}_\odot$|. We use mock observations to demonstrate the viability of a forward modelling approach to extract information about low-mass dark haloes lying along the line of sight to galaxy–galaxy strong lenses. This can be used to constrain the mass of a thermal relic dark matter particle, mDM . With 50 strong lenses at Hubble Space Telescope resolution and a maximum pixel signal-to-noise ratio of ∼50, the expected median 2σ constraint for a CDM-like model (with a halo mass cutoff at |$10^{7}\, {\rm M}_\odot$|) is |$m_\mathrm{DM} \gt 4.10 \, \mathrm{keV}$| (50 per cent chance of constraining mDM to be better than 4.10 keV). If, however, the dark matter is a warm particle of |$m_\mathrm{DM}=2.2 \, \mathrm{keV}$| , our 'approximate Bayesian computation' method would result in a median estimate of mDM between 1.43 and 3.21 keV. Our method can be extended to the large samples of strong lenses that will be observed by future telescopes and could potentially rule out the standard CDM model of cosmogony. To aid future survey design, we quantify how these constraints will depend on data quality (spatial resolution and integration time) as well as on the lensing geometry (source and lens redshifts). [ABSTRACT FROM AUTHOR]- Published
- 2022
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21. Halo concentration strengthens dark matter constraints in galaxy–galaxy strong lensing analyses.
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Amorisco, Nicola C, Nightingale, James, He, Qiuhan, Amvrosiadis, Aristeidis, Cao, Xiaoyue, Cole, Shaun, Etherington, Amy, Frenk, Carlos S, Li, Ran, Massey, Richard, and Robertson, Andrew
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DARK matter , *GRAVITATIONAL lenses , *GALACTIC halos , *MAGNITUDE (Mathematics) - Abstract
A defining prediction of the cold dark matter cosmological model is the existence of a very large population of low-mass haloes. This population is absent in models in which the dark matter particle is warm (WDM). These alternatives can, in principle, be distinguished observationally because haloes along the line of sight can perturb galaxy–galaxy strong gravitational lenses. Furthermore, the WDM particle mass could be deduced because the cut-off in their halo mass function depends on the mass of the particle. We systematically explore the detectability of low-mass haloes in WDM models by simulating and fitting mock lensed images. Contrary to previous studies, we find that haloes are harder to detect when they are either behind or in front of the lens. Furthermore, we find that the perturbing effect of haloes increases with their concentration: Detectable haloes are systematically high-concentration haloes, and accounting for the scatter in the mass–concentration relation boosts the expected number of detections by as much as an order of magnitude. Haloes have lower concentration for lower particle masses and this further suppresses the number of detectable haloes beyond the reduction arising from the lower halo abundances alone. Taking these effects into account can make lensing constraints on the value of the mass function cut-off at least an order of magnitude more stringent than previously appreciated. [ABSTRACT FROM AUTHOR]
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- 2022
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22. Trans-oral robotic surgery: a safe and effective tool in head and neck surgery in an Australian rural setting.
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Huang, Johnson, Phillips, Nicholas, Nightingale, James, Kondalsamy-Chennakesavan, Srinivas, Grigg, Roger, and Mahendran, Suresh
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SURGICAL robots ,NECK ,TUMOR surgery ,SURGERY ,HEAD - Abstract
Background: Trans-oral robotic surgery (TORS) facilitates surgical resection of tumours as an alternative to open surgery and has demonstrated favourable oncological results. Given the novelty of TORS and the paucity of evidence on TORS-specific complications in a rural setting, we report our experience with TORS at an Australian rural head and neck centre. Methods: A retrospective review of all robotic cases performed at a regional head and neck centre in Queensland was undertaken from 2014 to 2019. Patient demographics, preoperative surgical risk, complications and outcomes such as margins and cancer recurrence were recorded. Complications were graded based on the Clavien-Dindo grading system. Descriptive statistics were used to present patient characteristics and statistical analyses were performed using Stata. Results: Forty-two TORS surgeries were performed. Twenty-one had histology confirming malignancy. There were no adverse intraoperative effects. Overall, seven patients (16.7%) had at least one complication. Four were recorded as a Clavien-Dindo 3b (post-operative bleed, wound infection and drain dislodgment). Of two cases with residual positive margins, one declined further surgery, and another received chemoradiotherapy. One patient recurred with distant metastatic disease, and another had locoregional nodal recurrence. The distribution of complications was significant across the pre-operative risk categories for both American Society of Anaesthesiologists and surgical risk score (P = 0.02). Conclusion: TORS in a rural head and neck centre is a safe and viable treatment option for patients so long as this is undertaken with appropriate training, mentorship and teamwork. [ABSTRACT FROM AUTHOR]
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- 2021
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23. Flow-Through System Effects on in Vitro Analysis of Transdermal Systems
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Sclafani, Joseph, Nightingale, James, Liu, Puchun, and Kurihara-Bergstrom, Tamie
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- 1993
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24. Solid-State Ionic Liquid: Key to Efficient Detection and Discrimination in Organic Semiconductor Gas Sensors.
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Limbu, Saurav, Stewart, Katherine, Nightingale, James, Yan, Hao, Balamurugan, Chandran, Hong, Soonil, Kim, Jehan, Lee, Kwanghee, Kwon, Sooncheol, and Kim, Ji-Seon
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- 2021
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25. Outpatient surgical management of non‐melanoma skin cancers of the head and neck in a regional centre: an analysis of costs and outcomes.
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Nightingale, James, Travers, Liam, Campbell, Jakob, Huang, Johnson, Green, Megan, Warren, Tim, and Fitzgerald, Garret
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HEAD & neck cancer , *SKIN cancer , *BASAL cell carcinoma , *COST analysis , *SQUAMOUS cell carcinoma , *MOHS surgery - Abstract
Background: Non‐melanoma skin cancer is the most commonly diagnosed malignancy in Australia. Lesions of the head and neck are often outside the scope of primary care providers. The challenges of cancer care in regional Australia necessitate careful resource planning. This study presents an outpatient model that minimizes health service cost with local general practitioner follow‐up. Methods: A retrospective review of 105 patients with 122 skin lesions in a dedicated Facial Lesion Assessment Management and Excision clinic was performed from July 2018 to 2019. Clinical outcomes, patient travel and cost analysis/comparison were recorded. Results: There were 85 malignant cases with 59 basal cell carcinomas and 25 squamous cell carcinomas. For basal cell carcinoma, clear margins (≥3 mm), close margins (<3 mm) and positive margins were achieved in 24 (48%), 23 (46%) and three (6%) cases, respectively. For squamous cell carcinoma, clear margins (≥5 mm), close margins (<5 mm) and positive margins were achieved in seven (38.8%), 11 (61.1%) and none (0%) of the cases, respectively. Complications included one haematoma and two wound infections. For 37% of patients living >100 km from the department, 72.3% had local general practitioner follow‐up. Inpatient cost was $2870, $5697 and $9300 for primary closure, local flap and full‐thickness skin graft, respectively, and outpatient cost was $746 for a single facial lesion. Conclusion: This study presents a cost‐effective model for the management of non‐melanoma skin cancers with improved departmental efficiency and streamlined patient care in an outpatient skin cancer management model in a regional centre. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
26. Molecular understanding of a π-conjugated polymer/solid-state ionic liquid complex as a highly sensitive and selective gas sensor.
- Author
-
Stewart, Katherine, Limbu, Saurav, Nightingale, James, Pagano, Katia, Park, Byoungwook, Hong, Soonil, Lee, Kwanghee, Kwon, Sooncheol, and Kim, Ji-Seon
- Abstract
Electric-field driven chemical doping modulation in a blend of solution-processed organic semiconductors (OSCs) and solid-state ionic liquids (SSILs) in response to volatile organic compounds (VOCs) provides a new exciting opportunity to facilitate printable and low-power chemical gas sensors (chemiresistors). In order to fully exploit this opportunity, a fundamental understanding of the molecular-level interactions among the OSCs, SSILs, and VOC components during the device operation is urgently needed. Herein, we demonstrate a highly sensitive and selective VOC gas sensor using π-conjugated polymer (here, P3HT as a model homopolymer) and SSIL blends. A newly developed SSIL forms a semi-crystalline solid at room temperature. P3HT with high molecular weight and regioregularity allows an extremely well-interconnected network in blends desirable for efficient charge transport. In P3HT:SSIL blends, we identify electric-field driven strong chemical interactions between π-CP and SSIL to tune the electrical conductivity of the π-CP. The enlarged interfacial areas in blends and the solid-state nature of the SSIL ensure highly tunable electrochemical interactions between them, efficiently modulating the electrical conductivity of the π-CP further upon exposure to different polar and non-polar VOCs. Our results demonstrate the π-conjugated polymer/SSIL complex as a new highly sensitive and selective gas sensor and provide a key scientific understanding of its molecular-level operational mechanism critical for developing molecular sensors towards next generation noninvasive diagnostics. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
27. Small molecule additive for low-power accumulation mode organic electrochemical transistors.
- Author
-
Nightingale, James, Pitsalidis, Charalampos, Pappa, Anna-Maria, Tan, Ellasia, Stewart, Katherine, Owens, Róisín M., and Kim, Ji-Seon
- Abstract
Low-voltage operation in accumulation mode organic electrochemical transistors (OECTs) is essential for biosensing applications and for potential use with low-voltage portable power supplies. Here, we employ a small molecule additive, dodecylbenzenesulfonate (DBSA), by adding it to the electrolyte in OECTs to improve the device performance. We find that DBSA lowers the operation voltage, increases the ON current, and increases the transconductance of the device. Such improvements are found for a range of p-type polymers including P3HT, PBTTT and DPPT-TT which have different electronic and structural properties. To investigate the device operational mechanism modulated by DBSA, we directly probe the molecular structure changes of three polymers upon charge injection (i.e. polaron formation) and correlate them to polaron density and OECT performance. We find that the electrolyte mixture (containing DBSA) enhances the electrochemical doping of the polymer by lowering the onset of oxidation and allowing the generation of a higher polaron density. For example, for P3HT the V
ON value decreases to 0.05 V, the ON current increases by ∼3 times, and the transconductance (gm ) increases to 4 mS, which is, to the best of our knowledge, the highest transconductance of P3HT OECT reported. These results demonstrate a simple, but effective way of using a small molecule additive, such as DBSA, and a possibility to utilise otherwise unsuitable polymers with deep highest occupied molecular orbital (HOMO) levels, for low-power accumulation mode OECTs. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
28. A highly sensitive molecular structural probe applied to in situ biosensing of metabolites using PEDOT:PSS.
- Author
-
Tan, Ellasia, Pappa, Anna‐Maria, Pitsalidis, Charalampos, Nightingale, James, Wood, Sebastian, Castro, Fernando A., Owens, Róisín M., and Kim, Ji‐Seon
- Abstract
A large amount of research within organic biosensors is dominated by organic electrochemical transistors (OECTs) that use conducting polymers such as poly(3,4‐ethylene dioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS). Despite the recent advances in OECT‐based biosensors, the sensing is solely reliant on the amperometric detection of the bioanalytes. This is typically accompanied by large undesirable parasitic electrical signals from the electroactive components in the electrolyte. Herein, we present the use of in situ resonance Raman spectroscopy to probe subtle molecular structural changes of PEDOT:PSS associated with its doping level. We demonstrate how such doping level changes of PEDOT:PSS can be used, for the first time, on operational OECTs for sensitive and selective metabolite sensing while simultaneously performing amperometric detection of the analyte. We test the sensitivity by molecularly sensing a lowest glucose concentration of 0.02 mM in phosphate‐buffered saline solution. By changing the electrolyte to cell culture media, the selectivity of in situ resonance Raman spectroscopy is emphasized as it remains unaffected by other electroactive components in the electrolyte. The application of this molecular structural probe highlights the importance of developing biosensing probes that benefit from high sensitivity of the material's structural and electrical properties while being complimentary with the electronic methods of detection. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
29. Galaxy structure with strong gravitational lensing: decomposing the internal mass distribution of massive elliptical galaxies.
- Author
-
Nightingale, James W, Massey, Richard J, Harvey, David R, Cooper, Andrew P, Etherington, Amy, Tam, Sut-Ieng, and Hayes, Richard G
- Subjects
- *
GRAVITATIONAL lenses , *ELLIPTICAL galaxies , *STELLAR mass , *GALAXIES , *CIRCUMSTELLAR matter , *GALAXY formation - Abstract
We investigate how strong gravitational lensing can test contemporary models of massive elliptical (ME) galaxy formation, by combining a traditional decomposition of their visible stellar distribution with a lensing analysis of their mass distribution. As a proof of concept, we study a sample of three ME lenses, observing that all are composed of two distinct baryonic structures, a 'red' central bulge surrounded by an extended envelope of stellar material. Whilst these two components look photometrically similar, their distinct lensing effects permit a clean decomposition of their mass structure. This allows us to infer two key pieces of information about each lens galaxy: (i) the stellar mass distribution (without invoking stellar populations models) and (ii) the inner dark matter halo mass. We argue that these two measurements are crucial to testing models of ME formation, as the stellar mass profile provides a diagnostic of baryonic accretion and feedback whilst the dark matter mass places each galaxy in the context of LCDM large-scale structure formation. We also detect large rotational offsets between the two stellar components and a lopsidedness in their outer mass distributions, which hold further information on the evolution of each ME. Finally, we discuss how this approach can be extended to galaxies of all Hubble types and what implication our results have for studies of strong gravitational lensing. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
30. Colour in bivalve shells: Using resonance Raman spectroscopy to compare pigments at different phylogenetic levels.
- Author
-
Wade, Jessica, Pugh, Hazel, Nightingale, James, Kim, Ji‐Seon, and Williams, Suzanne T.
- Subjects
RESONANCE Raman spectroscopy ,BIVALVE shells ,CAROTENOIDS ,PIGMENTS ,RYANODINE receptors - Abstract
Several studies have suggested that shell colour may be phylogenetically distributed within the phylum Mollusca, but this pattern is confounded by our ignorance of the homology of colour and lack of understanding about the identity of most molluscan pigments. We use resonance Raman spectroscopy to address this problem by examining bivalve pigments producing a range of colours and compare spectra from taxa at different phylogenetic levels. The spectra of most shell pigments exhibited a skeletal signature typical of partially methylated polyenes, possibly modified carotenoids, with the strongest peaks occurring between 1,501–1,540 cm−1 and 1,117–1,144 cm−1 due to the C═C (ν1) and C–C (ν2) stretching modes, respectively. Neither pigment class nor mineral structure differentiated Imparidentia and Pteriomorphia. Spectral acquisitions for purple pigments for two species of Asaphis suggest that identical or nearly identical pigments are shared within this genus, and some red pigments from distantly related species have similar spectra. Conversely, two species with brown shells have distinctly different pigments, highlighting the difficulty in determining the homology of colour even within a single class of pigments. Curiously, we were unable to detect any Raman activity for green‐coloured shell or pigment peaks for the yellow area of Codakia paytenorum, suggesting that these colours are due to structural elements or a pigment that is quite different from those observed in other taxa examined to date. Our results are consistent with the idea that classes of pigments are evolutionarily ancient but heritable modifications may be specific to clades. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
31. Guest editorials: Special issue on fog/edge networking for multimedia applications.
- Author
-
Jin, Yong, Shen, Hang, D'Agostino, Daniele, Achir, Nadjib, and Nightingale, James
- Subjects
MULTIMEDIA communications ,NETWORK routing protocols ,FOG ,TIME delay estimation ,WIRELESS sensor networks ,EDGES (Geometry) - Abstract
Technological advancements have enabled emerging multimedia applications, which require massive devices with real-time communication, computation, and control. Some of these challenges include: how to design an efficient fog/edge Networking based multimedia Networking framework, how to make multimedia systems more intelligent, how to achieve the efficient multimedia data processing and distribution with edge/fog Networking, and how to design an efficient incentive mechanism for performance enhancement. The thirteenth paper by I Suqin Wu i on "Communication Modulation Recognition Algorithm based on STFT Mechanism in Combination with Unsupervised Feature-learning Network" proposed a novel recognition algorithm based on deep learning network far communication signal features for dealing with the limitations of traditional communication modulation recognition algorithms. [Extracted from the article]
- Published
- 2019
- Full Text
- View/download PDF
32. Dark matter dynamics in Abell 3827: new data consistent with standard cold dark matter.
- Author
-
Massey, Richard, Harvey, David, Liesenborgs, Jori, Richard, Johan, Stach, Stuart, Swinbank, Mark, Taylor, Peter, Williams, Liliya, Clowe, Douglas, Courbin, Frédéric, Edge, Alastair, Israel, Holger, Jauzac, Mathilde, Joseph, Rémy, Jullo, Eric, Kitching, Thomas D., Leonard, Adrienne, Merten, Julian, Nagai, Daisuke, and Nightingale, James
- Subjects
DARK matter ,VERY large telescopes ,SPIRAL galaxies ,INTEGRAL field spectroscopy ,COMPUTER simulation - Abstract
We present integral field spectroscopy of galaxy cluster Abell 3827, using Atacama Large Millimetre Array (ALMA) and Very Large Telescope/Multi-Unit Spectroscopic Explorer. It reveals an unusual configuration of strong gravitational lensing in the cluster core, with at least seven lensed images of a single background spiral galaxy. Lens modelling based on Hubble Space Telescope imaging had suggested that the dark matter associated with one of the cluster's central galaxies may be offset. The new spectroscopic data enable better subtraction of foreground light, and better identification of multiple background images. The inferred distribution of dark matter is consistent with being centred on the galaxies, as expected by Λ cold dark matter. Each galaxy's dark matter also appears to be symmetric. Whilst, we do not find an offset between mass and light (suggestive of self-interacting dark matter) as previously reported, the numerical simulations that have been performed to calibrate Abell 3827 indicate that offsets and asymmetry are still worth looking for in collisions with particular geometries. Meanwhile, ALMA proves exceptionally useful for strong lens image identifications. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
33. 5G-QoE: QoE Modelling for Ultra-HD Video Streaming in 5G Networks.
- Author
-
Nightingale, James, Salva-Garcia, Pablo, Calero, Jose M. Alcaraz, and Wang, Qi
- Subjects
- *
5G networks , *STREAMING video & television , *HIGH definition television , *TELEVISION broadcasting , *ULTRAHIGH definition television - Abstract
Traffic on future fifth-generation (5G) mobile networks is predicted to be dominated by challenging video applications such as mobile broadcasting, remote surgery and augmented reality, demanding real-time, and ultra-high quality delivery. Two of the main expectations of 5G networks are that they will be able to handle ultra-high-definition (UHD) video streaming and that they will deliver services that meet the requirements of the end user’s perceived quality by adopting quality of experience (QoE) aware network management approaches. This paper proposes a 5G-QoE framework to address the QoE modeling for UHD video flows in 5G networks. Particularly, it focuses on providing a QoE prediction model that is both sufficiently accurate and of low enough complexity to be employed as a continuous real-time indicator of the “health” of video application flows at the scale required in future 5G networks. The model has been developed and implemented as part of the EU 5G PPP SELFNET autonomic management framework, where it provides a primary indicator of the likely perceptual quality of UHD video application flows traversing a realistic multi-tenanted 5G mobile edge network testbed. The proposed 5G-QoE framework has been implemented in the 5G testbed, and the high accuracy of QoE prediction has been validated through comparing the predicted QoE values with not only subjective testing results but also empirical measurements in the testbed. As such, 5G-QoE would enable a holistic video flow self-optimisation system employing the cutting-edge Scalable H.265 video encoding to transmit UHD video applications in a QoE-aware manner. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
34. The SELFNET Approach for Autonomic Management in an NFV/SDN Networking Paradigm.
- Author
-
Neves, Pedro, Calé, Rui, Costa, Mário Rui, Parada, Carlos, Parreira, Bruno, Alcaraz-Calero, Jose, Wang, Qi, Nightingale, James, Chirivella-Perez, Enrique, Jiang, Wei, Schotten, Hans Dieter, Koutsopoulos, Konstantinos, Gavras, Anastasius, and Barros, Maria João
- Subjects
SOFTWARE-defined networking ,KEY performance indicators (Management) ,5G networks ,VIRTUAL networks ,COMPUTER network management - Abstract
To meet the challenging key performance indicators of the fifth generation (5G) system, the network infrastructure becomes more heterogeneous and complex. This will bring a high pressure on the reduction of OPEX and the improvement of the user experience. Hence, shifting today’s manual and semi-automatic network management into an autonomic and intelligent framework will play a vital role in the upcoming 5G system. Based on the cutting-edge technologies, such as Software-Defined Networking and Network Function Virtualization, a novel management framework upon the software-defined and Virtualized Network is proposed by EU H2020 SELFNET project. In the paper, the reference architecture of SELFNET, which is divided into Infrastructure Layer, Virtualized Network Layer, SON Control Layer, SON Autonomic Layer, NFV Orchestration and Management Layer, and Access Layer, will be presented. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
35. QoE-Driven, Energy-Aware Video Adaptation in 5G Networks: The SELFNET Self-Optimisation Use Case.
- Author
-
Nightingale, James, Wang, Qi, Alcaraz Calero, Jose M., Chirivella-Perez, Enrique, Ulbricht, Marian, Alonso-López, Jesús A., Preto, Ricardo, Batista, Tiago, Teixeira, Tiago, Barros, Maria Joao, and Reinsch, Christiane
- Subjects
- *
5G networks , *ENERGY consumption , *QUALITY of service , *VIRTUAL reality - Abstract
Sharp increase of video traffic is expected to account for the majority of traffic in future 5G networks. This paper introduces the SELFNET 5G project and describes the video streaming use case that will be used to demonstrate the self-optimising capabilities of SELFNET’s autonomic network management framework. SELFNET’s framework will provide an advanced self-organizing network (SON) underpinned by seamless integration of Software Defined Networking (SDN), Network Function Virtualization (NFV), and network intelligence. The self-optimisation video streaming use case is going beyond traditional quality of service approaches to network management. A set of monitoring and analysis components will facilitate a user-oriented, quality of experience (QoE) and energy-aware approach. Firstly, novel SON-Sensors will monitor both traditional network state metrics and new video and energy related metrics. The combination of these low level metrics provides highly innovative health of network (HoN) composite metrics. HoN composite metrics are processed via autonomous decisions not only maintaining but also proactively optimising users’ video QoE while minimising the end-to-end energy consumption of the 5G network. This contribution provided a detailed technical overview of this ambitious use case. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
36. Video adaptation for consumer devices: opportunities and challenges offered by new standards.
- Author
-
Nightingale, James, Wang, Qi, Grecos, Christos, and Goma, Sergio
- Subjects
- *
DATA compression (Telecommunication) , *STREAMING technology , *BANDWIDTH allocation , *HOUSEHOLD electronics , *MOBILE communication systems - Abstract
Video and multimedia streaming services continue to grow in popularity and are rapidly becoming the largest consumers of network capacity in both fixed and mobile networks. In this article we discuss the latest advances in video compression technology and demonstrate their potential to improve service quality for consumers while reducing bandwidth consumption. Our study focuses on the adaptation of scalable, highly compressed video streams to meet the resource constraints of a wide range of portable consumer devices in mobile environments. Exploring SHVC, the scalable extension to the recently standardized High Efficiency Video Coding scheme, we show the bandwidth savings that can be achieved over current encoding schemes and highlight the challenges that lie ahead in realizing a deployable and user-centric system. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
37. The impact of network impairment on quality of experience (QoE) in H.265/HEVC video streaming.
- Author
-
Nightingale, James, Wang, Qi, Grecos, Christos, and Goma, Sergio
- Subjects
- *
STREAMING video & television , *BENCHMARKING (Management) , *DATA packeting , *QUALITY standards , *ROBUST control , *BANDWIDTHS - Abstract
Users of modern portable consumer devices (smartphones, tablets etc.) expect ubiquitous delivery of high quality services, which fully utilise the capabilities of their devices. Video streaming is one of the most widely used yet challenging services for operators to deliver with assured service levels. This challenge is more apparent in wireless networks where bandwidth constraints and packet loss are common. The lower bandwidth requirements of High Efficiency Video Coding (HEVC) provide the potential to enable service providers to deliver high quality video streams in low-bandwidth networks; however, packet loss may result in greater damage in perceived quality given the higher compression ratio. This work considers the delivery of HEVC encoded video streams in impaired network environments and quantifies the effects of network impairment on HEVC video streaming from the perspective of the end user. HEVC encoded streams were transmitted over a test network with both wired and wireless segments that had imperfect communication channels subject to packet loss. Two different error concealment methods were employed to mitigate packet loss and overcome reference decoder robustness issues. The perceptual quality of received video was subjectively assessed by a panel of viewers. Existing subjective studies of HEVC quality have not considered the implications of network impairments. Analysis of results has quantified the effects of packet loss in HEVC on perceptual quality and provided valuable insight into the relative importance of the main factors observed to influence user perception in HEVC streaming. The outputs from this study show the relative importance and relationship between those factors that affect human perception of quality in impaired HEVC encoded video streams. The subjective analysis is supported by comparison with commonly used objective quality measurement techniques. Outputs from this work may be used in the development of quality of experience (QoE) oriented streaming applications for HEVC in loss prone networks. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
38. Performance Evaluation of Concurrent Multipath Video Streaming in Multihomed Mobile Networks.
- Author
-
Nightingale, James, Qi Wang, and Grecos, Christos
- Subjects
STREAMING video & television ,COMPUTER networks ,BANDWIDTHS ,VIDEO coding ,VIDEOS ,EMPIRICAL research - Abstract
High-quality real-time video streaming to users in mobile networks is challenging due to the dynamically changing nature of the network paths, particularly the limited bandwidth and varying end-to-end delay. In this paper, we empirically investigate the performance of multipath streaming in the context of multihomed mobile networks. Existing schemes that make use of the aggregated bandwidth of multiple paths can overcome bandwidth limitations on a single path but suffer an efficiency penalty caused by retransmission of lost packets in reliable transport schemes or path switching overheads in unreliable transport schemes. This work focuses on the evaluation of schemes to permit concurrent use of multiple paths to deliver video streams. A comprehensive streaming framework for concurrent multipath video streaming is proposed and experimentally evaluated, using current stateof- the-art H.264 Scalable Video Coding (H.264/SVC) and the next generation High Efficiency Video Coding (HEVC) standards. It provides a valuable insight into the benefit of using such schemes in conjunction with encoder specific packet prioritisation mechanisms for quality-aware packet scheduling and scalable streaming. The remaining obstacles to deployment of concurrent multipath schemes are identified, and the challenges in realising HEVC based concurrent multipath streaming are highlighted. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
39. Efficient Charge Carrier Injection and Balance Achieved by Low Electrochemical Doping in Solution‐Processed Polymer Light‐Emitting Diodes.
- Author
-
Yan, Hao, Limbu, Saurav, Wang, Xuhua, Nightingale, James, Hamilton, Iain, Wade, Jessica, Kwon, Sooncheol, Lee, Kwanghee, and Kim, Ji‐Seon
- Subjects
CHARGE injection ,CHARGE carriers ,ELECTROLUMINESCENCE ,DIODES ,HOLE mobility - Abstract
Charge carrier injection and transport in polymer light‐emitting diodes (PLEDs) is strongly limited by the energy level offset at organic/(in)organic interfaces and the mismatch in electron and hole mobilities. Herein, these limitations are overcome via electrochemical doping of a light‐emitting polymer. Less than 1 wt% of doping agent is enough to effectively tune charge injection and balance and hence significantly improve PLED performance. For thick single‐layer (1.2 µm) PLEDs, dramatic reductions in current and luminance turn‐on voltages (VJ = 11.6 V from 20.0 V and VL = 12.7 V from 19.8 V with/without doping) accompanied by reduced efficiency roll‐off are observed. For thinner (<100 nm) PLEDs, electrochemical doping removes a thickness dependence on VJ and VL, enabling homogeneous electroluminescence emission in large‐area doped devices. Such efficient charge injection and balance properties achieved in doped PLEDs are attributed to a strong electrochemical interaction between the polymer and the doping agents, which is probed by in situ electric‐field‐dependent Raman spectroscopy combined with further electrical and energetic analysis. This approach to control charge injection and balance in solution‐processed PLEDs by low electrochemical doping provides a simple yet feasible strategy for developing high‐quality and efficient lighting applications that are fully compatible with printing technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
40. Special Issue on Mobile Multimedia Big Data Embedded Systems.
- Author
-
Gelan Yang and Nightingale, James
- Subjects
- *
BIG data , *EMBEDDED computer systems , *MULTIMEDIA systems , *MULTIMEDIA communications , *TECHNOLOGICAL innovations - Published
- 2018
- Full Text
- View/download PDF
41. Cognition Cloud Model for Next Generation Mobile Internet: Communication, Control, and Application.
- Author
-
Jin, Yong, Yan, Chaobo, and Nightingale, James
- Subjects
CLOUD computing ,WIRELESS Internet ,RESOURCE allocation - Published
- 2016
- Full Text
- View/download PDF
42. Surgia -- inspiring future surgeons and anaesthetists at Griffith University Medical School.
- Author
-
Nightingale, James, Cattanach, Daniel, and Dolan-Evans, Elliot
- Published
- 2013
43. HEVStream: a framework for streaming and evaluation of high efficiency video coding (HEVC) content in loss-prone networks.
- Author
-
Nightingale, James, Wang, Qi, and Grecos, Christos
- Subjects
- *
STREAMING technology , *VIDEO coding , *BANDWIDTHS , *IMAGE quality in imaging systems , *TIME delay systems , *SIGNAL-to-noise ratio - Abstract
High Efficiency Video Coding (HEVC) is the next generation video compression standard currently under development within the ITU-T/ISO sponsored Joint Collaborative Team on Video Coding (JCT-VC). The standardization, and eventual adoption, of HEVC will contribute significantly to the future development of many consumer devices. Areas such as broadcast television, multimedia streaming, mobile communications and multimedia/video content storage will all be impacted by implementation of the emerging HEVC standard. Up to this point in time the research focus of HEVC has been on improvements to video compression efficiency and little work has been conducted into streaming of HEVC. In this work we consider the practical barriers to HEVC streaming in realistic environments and propose HEVStream, a streaming and evaluation framework for HEVC encoded content. Our framework fills the current gap in enabling networked HEVC visual applications and permits the implementation, testing and evaluation of HEVC encoded video streaming under a range of packet loss, bandwidth restriction and network delay scenarios in a realistic testbed environment. We provide a basic error concealment method for HEVC to overcome limitations within the decoder and an RTP packetisation format for HEVC Network Abstraction Layer (NAL) units. Comprehensive results of HEVC streaming experiments under various network circumstances are reported. These results provide an insight into the reduction in picture quality, measured as peak signal to noise ratio (PSNR), that can be expected under a wide range of network constraint and packet loss conditions. We report an average loss of 3.61dB when a bandwidth reduction of 10% is applied. We believe that this work will be amongst the first to report on successful design and implementation of HEVC network applications, and evaluation of the effects of network constraints or limitations on the quality of HEVC encoded video streams. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
44. Removing path-switching cost in video delivery over multiple paths in mobile networks.
- Author
-
Nightingale, James, Wang, Qi, and Grecos, Christos
- Subjects
- *
STREAMING video & television , *MOBILE communication systems , *SWITCHING theory , *STREAMING technology , *ARTIFICIAL neural networks , *SYNCHRONOUS capacitors , *BANDWIDTHS - Abstract
The pace at which powerful portable wireless consumer devices such as smartphones and tablets have been adopted has not been matched by the ability of mobile networks to deliver high-quality video streams consistently to such nomadic users. In this work, we propose CMT-NEMO, a novel concurrent multipath transfer scheme for the delivery of scalable video content to users in multihomed mobile networks such as those expected to be found in public transport scenarios. Recent research in this context has shown that the single largest limiting factor for perceived video quality is the overhead introduced by path switching operations in multihomed mobile networks. CMT-NEMO eliminates the need for path switching and, by removing the associated path switching latency, provides a substantial performance improvement across a wide range of bandwidths and test sequences. An average Y-PSNR improvement of 5.9 dB is achieved when compared with previously proposed schemes. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
45. Optimised transmission of H.264 scalable video streams over multiple paths in mobile networks.
- Author
-
Nightingale, James, Wang, Qi, and Grecos, Christos
- Subjects
- *
STREAMING video & television , *MOBILE communication systems , *WIRELESS communications , *SMARTPHONES , *SCALABILITY , *MOBILE computing , *SYNCHRONOUS capacitors - Abstract
Consumer demand for portable wireless devices such as smartphones or tablets capable of receiving high quality video content has risen sharply in recent years. This paper considers the real-time delivery of streamed H.264 Scalable Video Coding (SVC) content to users of such devices within mobile networks (e.g. situations where they are part of a group moving together on a bus or a train). We propose a novel scheme for the multipath delivery of H.264 SVC content to users in multihomed mobile networks .By implementing our scheme on a realistic testbed, we show that it offers a significant improvement in received video quality over previously proposed alternative schemes1. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
46. Variation of human skin permeation in vitro: Ionic vs neutral compounds
- Author
-
Liu, Puchun, Nightingale, James A.S., and Kurihara-Bergstrom, Tamie
- Published
- 1993
- Full Text
- View/download PDF
47. Enhanced transdermal delivery of estradiol in vitro using binary vehicles of isopropyl myristate and short-chain alkanols
- Author
-
Goldberg-Cettina, Melinda, Liu, Puchun, Nightingale, James, and Kurihara-Bergstrom, Tamie
- Published
- 1995
- Full Text
- View/download PDF
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