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"Chambers, K"
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The Spectroscopic Classification of Astronomical Transients (SCAT) Survey: Overview, Pipeline Description, Initial Results, and Future Plans
by
Desai, D. D.
,
Auchettl, K.
,
de Jaeger, T.
in
Active galactic nuclei
,
ASTRONOMY AND ASTROPHYSICS
,
Atmospheric extinction
2022
We present the Spectroscopic Classification of Astronomical Transients (SCAT) survey, which is dedicated to spectrophotometric observations of transient objects such as supernovae and tidal disruption events. SCAT uses the SuperNova Integral-Field Spectrograph (SNIFS) on the University of Hawai’i 2.2 m (UH2.2m) telescope. SNIFS was designed specifically for accurate transient spectrophotometry, including absolute flux calibration and host-galaxy removal. We describe the data reduction and calibration pipeline including spectral extraction, telluric correction, atmospheric characterization, nightly photometricity, and spectrophotometric precision. We achieve ≲5% spectrophotometry across the full optical wavelength range (3500–9000 Å) under photometric conditions. The inclusion of photometry from the SNIFS multi-filter mosaic imager allows for decent spectrophotometric calibration (10%–20%) even under unfavorable weather/atmospheric conditions. SCAT obtained ≈640 spectra of transients over the first 3 yr of operations, including supernovae of all types, active galactic nuclei, cataclysmic variables, and rare transients such as superluminous supernovae and tidal disruption events. These observations will provide the community with benchmark spectrophotometry to constrain the next generation of hydrodynamic and radiative transfer models.
Journal Article
Robot-assisted laparoscopic prostatectomy versus open radical retropubic prostatectomy: early outcomes from a randomised controlled phase 3 study
2016
The absence of trial data comparing robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy is a crucial knowledge gap in uro-oncology. We aimed to compare these two approaches in terms of functional and oncological outcomes and report the early postoperative outcomes at 12 weeks.
In this randomised controlled phase 3 study, men who had newly diagnosed clinically localised prostate cancer and who had chosen surgery as their treatment approach, were able to read and speak English, had no previous history of head injury, dementia, or psychiatric illness or no other concurrent cancer, had an estimated life expectancy of 10 years or more, and were aged between 35 years and 70 years were eligible and recruited from the Royal Brisbane and Women's Hospital (Brisbane, QLD). Participants were randomly assigned (1:1) to receive either robot-assisted laparoscopic prostatectomy or radical retropubic prostatectomy. Randomisation was computer generated and occurred in blocks of ten. This was an open trial; however, study investigators involved in data analysis were masked to each patient's condition. Further, a masked central pathologist reviewed the biopsy and radical prostatectomy specimens. Primary outcomes were urinary function (urinary domain of EPIC) and sexual function (sexual domain of EPIC and IIEF) at 6 weeks, 12 weeks, and 24 months and oncological outcome (positive surgical margin status and biochemical and imaging evidence of progression at 24 months). The trial was powered to assess health-related and domain-specific quality of life outcomes over 24 months. We report here the early outcomes at 6 weeks and 12 weeks. The per-protocol populations were included in the primary and safety analyses. This trial was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), number ACTRN12611000661976.
Between Aug 23, 2010, and Nov 25, 2014, 326 men were enrolled, of whom 163 were randomly assigned to radical retropubic prostatectomy and 163 to robot-assisted laparoscopic prostatectomy. 18 withdrew (12 assigned to radical retropubic prostatectomy and six assigned to robot-assisted laparoscopic prostatectomy); thus, 151 in the radical retropubic prostatectomy group proceeded to surgery and 157 in the robot-assisted laparoscopic prostatectomy group. 121 assigned to radical retropubic prostatectomy completed the 12 week questionnaire versus 131 assigned to robot-assisted laparoscopic prostatectomy. Urinary function scores did not differ significantly between the radical retropubic prostatectomy group and robot-assisted laparoscopic prostatectomy group at 6 weeks post-surgery (74·50 vs 71·10; p=0·09) or 12 weeks post-surgery (83·80 vs 82·50; p=0·48). Sexual function scores did not differ significantly between the radical retropubic prostatectomy group and robot-assisted laparoscopic prostatectomy group at 6 weeks post-surgery (30·70 vs 32·70; p=0·45) or 12 weeks post-surgery (35·00 vs 38·90; p=0·18). Equivalence testing on the difference between the proportion of positive surgical margins between the two groups (15 [10%] in the radical retropubic prostatectomy group vs 23 [15%] in the robot-assisted laparoscopic prostatectomy group) showed that equality between the two techniques could not be established based on a 90% CI with a Δ of 10%. However, a superiority test showed that the two proportions were not significantly different (p=0·21). 14 patients (9%) in the radical retropubic prostatectomy group versus six (4%) in the robot-assisted laparoscopic prostatectomy group had postoperative complications (p=0·052). 12 (8%) men receiving radical retropubic prostatectomy and three (2%) men receiving robot-assisted laparoscopic prostatectomy experienced intraoperative adverse events.
These two techniques yield similar functional outcomes at 12 weeks. Longer term follow-up is needed. In the interim, we encourage patients to choose an experienced surgeon they trust and with whom they have rapport, rather than a specific surgical approach.
Cancer Council Queensland.
Journal Article
The handbook of language variation and change
by
J.K. Chambers
,
Natalie Schilling
in
Language and languages
,
LANGUAGE ARTS & DISCIPLINES
,
Linguistic change
2013
Reflecting a multitude of developments in the study of language change and variation over the last ten years, this extensively updated second edition features a number of new chapters and remains the authoritative reference volume on a core research area in linguistics. * A fully revised and expanded edition of this acclaimed reference work, which has established its reputation based on its unrivalled scope and depth of analysis in this interdisciplinary field * Includes seven new chapters, while the remainder have undergone thorough revision and updating to incorporate the latest research and reflect numerous developments in the field * Accessibly structured by theme, covering topics including data collection and evaluation, linguistic structure, language and time, language contact, language domains, and social differentiation * Brings together an experienced, international editorial and contributor team to provides an unrivalled learning, teaching and reference tool for researchers and students in sociolinguistics
The Microwell-mesh: A high-throughput 3D prostate cancer spheroid and drug-testing platform
2018
Treatment following early diagnosis of Prostate cancer (PCa) is increasingly successful, whilst the treatment of advanced and metastatic PCa remains challenging. A major limitation in the development of new therapies is the prediction of drug efficacy using
in vitro
models. Classic
in vitro
2-dimensional (2D) cell monolayer cultures are hypersensitive to anti-cancer drugs. As a result, there has been a surge in the development of platforms that enable three dimensional (3D) cultures thought to better replicate natural physiology and better predict drug efficacy. A deficiency associated with most 3D culture systems is that their complexity reduces the number of replicates and combination therapies that can be feasibly evaluated. Herein, we describe the use of a microwell platform that utilises a nylon mesh to retain 3D micro-tumours in discrete microwells; termed the
Microwell-mesh
. The Microwell-mesh enables the manufacture of ~150 micro-tumours per well in a 48-well plate, and response to anti-tumour drugs can be readily quantified. Our results demonstrate that 3D micro-tumours, unlike 2D monolayers, are not hypersensitive to Docetaxel or Abiraterone Acetate, providing a superior platform for the evaluation of sequential drug treatment. In summary, the Microwell-mesh provides an efficient 3D micro-tumour platform for single and sequential drug screening.
Journal Article
The Luminous Type Ia Supernova 2022ilv and Its Early Excess Emission
2023
We present observations and analysis of the hostless and luminous Type Ia supernova 2022ilv, illustrating it is part of the 2003fg-like family, often referred to as super-Chandrasekhar (Ia-SC) explosions. The Asteroid Terrestrial-impact Last Alert System light curve shows evidence of a short-lived, pulse-like early excess, similar to that detected in another luminous Type Ia supernova (SN 2020hvf). The light curve is broad, and the early spectra are remarkably similar to those of SN 2009dc. Adopting a redshift of z = 0.026 ± 0.005 for SN 2022ilv based on spectral matching, our model light curve requires a large 56Ni mass in the range 0.7–1.5 M ⊙ and a large ejecta mass in the range 1.6–2.3 M ⊙. The early excess can be explained by fast-moving SN ejecta interacting with a thin, dense shell of circumstellar material close to the progenitor (∼1013 cm) a few hours after the explosion. This may be realized in a double-degenerate scenario, wherein a white dwarf merger is preceded by the ejection of a small amount (∼10−3–10−2 M ⊙) of hydrogen and helium-poor tidally stripped material. A deep pre-explosion Pan-STARRS1 stack indicates no host galaxy to a limiting magnitude of r ∼ 24.5. This implies a surprisingly faint limit for any host of M r ≳ −11, providing further evidence that these types of explosions occur predominantly in low-metallicity environments.
Journal Article
The fastest unbound star in our Galaxy ejected by a thermonuclear supernova
2015
Hypervelocity stars (HVSs) travel with velocities so high that they exceed the escape velocity of the Galaxy. Several acceleration mechanisms have been discussed. Only one HVS (US 708, HVS 2) is a compact helium star. Here we present a spectroscopic and kinematic analysis of US 708. Traveling with a velocity of ∼1200 kilometers per second, it is the fastest unbound star in our Galaxy. In reconstructing its trajectory, the Galactic center becomes very unlikely as an origin, which is hardly consistent with the most favored ejection mechanism for the other HVSs. Furthermore, we detected that US 708 is a fast rotator. According to our binary evolution model, it was spun-up by tidal interaction in a close binary and is likely to be the ejected donor remnant of a thermonuclear supernova.
Journal Article
Robot-assisted laparoscopic prostatectomy versus open radical retropubic prostatectomy: 24-month outcomes from a randomised controlled study
by
Chambers, Suzanne K
,
Williams, Scott
,
Coughlin, Geoffrey D
in
Cancer surgery
,
Clinical trials
,
Data processing
2018
Previous trials have found similar early outcomes after robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy. We report functional and oncological postoperative outcomes up to 24 months after surgery for these two surgical techniques.
In this randomised controlled phase 3 study, men who had newly diagnosed clinically localised prostate cancer and who had chosen surgery as their treatment approach, and were aged between 35 years and 70 years were eligible and recruited from the Royal Brisbane and Women's Hospital (Brisbane, QLD, Australia). Participants were randomly assigned (1:1) to have either robot-assisted laparoscopic prostatectomy or open radical retropubic prostatectomy. Randomisation was computer generated and occurred in blocks of ten. This was an open trial; however, study investigators involved in data analysis were masked to each patient's surgical treatment. Primary outcomes were urinary function (urinary domain of Expanded Prostate Cancer Index Composite [EPIC]) and sexual function (sexual domain of EPIC and International Index of Erectile Function Questionnaire [IIEF]) at 6 months, 12 months, and 24 months and oncological outcome (biochemical recurrence and imaging evidence of progression). The trial was powered to assess health-related and domain-specific quality-of-life outcomes over 24 months. All analyses were done on a per-protocol basis. The trial was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12611000661976.
Between Aug 23, 2010, and Nov 25, 2014, 326 men were enrolled, of whom 163 were randomly assigned to robot-assisted laparoscopic prostatectomy and 163 to open radical retropubic prostatectomy. 18 withdrew (12 assigned to radical retropubic prostatectomy and six assigned to robot-assisted laparoscopic prostatectomy); thus, 151 in the radical retropubic prostatectomy group and 157 in the robot-assisted laparoscopic prostatectomy group proceeded to surgery. At the 24-month follow-up time point, 150 men remained in the robot-assisted laparoscopic prostatectomy group and 146 remained in the open radical retropubic prostatectomy group. Urinary function scores did not differ significantly between robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy at 6 months post-surgery (88·68 [95% CI 86·79–90·58] vs 88·45 [86·54–90·36]; p1<0·0001, p2<0·0001), 12 months post-surgery (90·76 [88·89–92·62] vs 91·53 [90·07–92·98]; p1<0·0001, p2<0·0001), or 24 months post-surgery (91·33 [89·64–93·03] vs 90·86 [89·01–92·70]; p1<0·0001, p2<0·0001). Sexual function scores were not significantly different between robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy at 6 months post-surgery (EPIC: 37·40 [33·60–41·19] vs 38·63 [34·76–42·49], p1=0·0001, p2<0·0001; IIEF: 29·75 [26·66–32·84] vs 29·78 [26·41–33·16], p1<0·0001, p2<0·0001), 12 months post-surgery (EPIC: 42·28 [38·05–46·51] vs 42·51 [38·29–46·72], p1<0·0001, p2<0·0001; IIEF: 33·10 [29·59–36·61] vs 33·50 [29·87–37·13], p1=0·0002, p2<0·0001), or 24 months post-surgery (EPIC: 45·70 [41·17–50·23] vs 46·90 [42·20–51·60], p1=0·0003, p2<0·0001; IIEF: 33·95 [30·11–37·78] vs 33·89 [29·82–37·96], p1=0·0003, p2=0·0004). Equivalence testing on the difference between the proportion of biochemical recurrences between the two groups (13 [9%] in the open radical retropubic prostatectomy group vs four [3%] in the robot-assisted laparoscopic prostatectomy group) showed that equality between the two techniques could not be established based on a 90% CI with a prespecified margin of 10%. However, a superiority test showed that the two proportions were significantly different (p=0·0199). Equivalence testing on the proportion of patients who had imaging evidence of progression revealed that the two groups were not significantly different (p=0·2956).
Robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy yielded similar functional outcomes at 24 months. We advise caution in interpreting the oncological outcomes of our study because of the absence of standardisation in postoperative management between the two trial groups and the use of additional cancer treatments. Clinicians and patients should view the benefits of a robotic approach as being largely related to its minimally invasive nature.
Cancer Council Queensland.
Journal Article
Identification of the Optical Counterpart of the Fast X-Ray Transient EP240414a
2025
Fast X-ray transients (FXTs) are extragalactic bursts of X-rays first identified in archival X-ray data and are now routinely discovered in real time by the Einstein Probe, which is continuously surveying the night sky in the soft (0.5–4 keV) X-ray regime. In this Letter, we report the discovery of the second optical counterpart (AT 2024gsa) to an FXT (EP 240414a). EP 240414a is located at a projected radial separation of 27 kpc from its likely host galaxy at z = 0.4018 ± 0.0010. The optical light curve of AT 2024gsa displays three distinct components. The initial decay from our first observation is followed by a rebrightening episode, displaying a rapid rise in luminosity to an absolute magnitude Mr ∼ −21 after two rest-frame days. While the early optical luminosity and decline rate are similar to those of luminous fast blue optical transients, the color temperature of AT 2024gsa is distinctly red and we show that the peak flux is inconsistent with a thermal origin. The third component peaks at Mi ∼ −19 at ≳16 rest-frame days post-FXT, and is compatible with an emerging supernova. We fit the riz-band data with a series of power laws and find that the decaying components are in agreement with gamma-ray burst afterglow models, and that the rebrightening may originate from refreshed shocks. By considering EP 240414a in context with all previously reported known-redshift FXT events, we propose that Einstein Probe FXT discoveries may predominantly result from (high-redshift) gamma-ray bursts, and thus appear to be distinct from the previously discovered lower-redshift, lower-luminosity population of FXTs.
Journal Article
A systematic review of the impact of stigma and nihilism on lung cancer outcomes
by
Sinclair, Sue
,
Chambers, Suzanne K
,
Hughes, Suzanne
in
Analysis
,
Attitude of Health Personnel
,
Biomedical and Life Sciences
2012
Background
This study systematically reviewed the evidence on the influence of stigma and nihilism on lung cancer patterns of care; patients’ psychosocial and quality of life (QOL) outcomes; and how this may link to public health programs.
Methods
Medline, EMBASE, ProQuest, CINAHL, PsycINFO databases were searched. Inclusion criteria were: included lung cancer patients and/or partners or caregivers and/or health professionals (either at least 80% of participants had lung cancer or were partners or caregivers of lung cancer patients, or there was a lung cancer specific sub-group focus or analysis), assessed stigma or nihilism with respect to lung cancer and published in English between 1
st
January 1999 and 31
st
January 2011. Trial quality and levels of evidence were assessed.
Results
Eighteen articles describing 15 studies met inclusion criteria. The seven qualitative studies were high quality with regard to data collection, analysis and reporting; however most lacked a clear theoretical framework; did not address interviewer bias; or provide a rationale for sample size. The eight quantitative studies were generally of low quality with highly selected samples, non-comparable groups and low participation rates and employed divergent theoretical and measurement approaches. Stigma about lung cancer was reported by patients and health professionals and was related to poorer QOL and higher psychological distress in patients. Clear empirical explorations of nihilism were not evident. There is qualitative evidence that from the patients’ perspectives public health programs contribute to stigma about lung cancer and this was supported by published commentary.
Conclusions
Health-related stigma presents as a part of the lung cancer experience however there are clear limitations in the research to date. Future longitudinal and multi-level research is needed and this should be more clearly linked to relevant theory.
Journal Article
The Circumstellar Environments of Double-peaked, Calcium-strong Transients 2021gno and 2021inl
2022
We present panchromatic observations and modeling of calcium-strong supernovae (SNe) 2021gno in the star-forming host-galaxy NGC 4165 and 2021inl in the outskirts of elliptical galaxy NGC 4923, both monitored through the Young Supernova Experiment transient survey. The light curves of both, SNe show two peaks, the former peak being derived from shock cooling emission (SCE) and/or shock interaction with circumstellar material (CSM). The primary peak in SN 2021gno is coincident with luminous, rapidly decaying X-ray emission (L x = 5 × 1041 erg s−1) detected by Swift-XRT at δ t = 1 day after explosion, this observation being the second-ever detection of X-rays from a calcium-strong transient. We interpret the X-ray emission in the context of shock interaction with CSM that extends to r < 3 × 1014 cm. Based on X-ray modeling, we calculate a CSM mass M CSM = (0.3−1.6) × 10−3 M ⊙ and density n = (1−4) × 1010 cm−3. Radio nondetections indicate a low-density environment at larger radii (r > 1016 cm) and mass-loss rate of Ṁ<10−4 M ⊙ yr−1. SCE modeling of both primary light-curve peaks indicates an extended-progenitor envelope mass M e = 0.02−0.05 M ⊙ and radius R e = 30−230 R ⊙. The explosion properties suggest progenitor systems containing either a low-mass massive star or a white dwarf (WD), the former being unlikely given the lack of local star formation. Furthermore, the environments of both SNe are consistent with low-mass hybrid He/C/O WD + C/O WD mergers.
Journal Article