In the past decade, our understanding of galaxy evolution has been revolutionized by the discovery that luminous, dusty starburst galaxies were 1,000 times more abundant in the early Universe than at ...present. It has, however, been difficult to measure the complete redshift distribution of these objects, especially at the highest redshifts (z > 4). Here we report a redshift survey at a wavelength of three millimetres, targeting carbon monoxide line emission from the star-forming molecular gas in the direction of extraordinarily bright millimetre-wave-selected sources. High-resolution imaging demonstrates that these sources are strongly gravitationally lensed by foreground galaxies. We detect spectral lines in 23 out of 26 sources and multiple lines in 12 of those 23 sources, from which we obtain robust, unambiguous redshifts. At least 10 of the sources are found to lie at z > 4, indicating that the fraction of dusty starburst galaxies at high redshifts is greater than previously thought. Models of lens geometries in the sample indicate that the background objects are ultra-luminous infrared galaxies, powered by extreme bursts of star formation.
We report the results of an 87 deg{sup 2} point-source survey centered at R.A. 5{sup h}30{sup m}, decl. -55{sup 0} taken with the South Pole Telescope at 1.4 and 2.0 mm wavelengths with arcminute ...resolution and milli-Jansky depth. Based on the ratio of flux in the two bands, we separate the detected sources into two populations, one consistent with synchrotron emission from active galactic nuclei and the other consistent with thermal emission from dust. We present source counts for each population from 11 to 640 mJy at 1.4 mm and from 4.4 to 800 mJy at 2.0 mm. The 2.0 mm counts are dominated by synchrotron-dominated sources across our reported flux range; the 1.4 mm counts are dominated by synchrotron-dominated sources above {approx}15 mJy and by dust-dominated sources below that flux level. We detect 141 synchrotron-dominated sources and 47 dust-dominated sources at signal-to-noise ratio S/N >4.5 in at least one band. All of the most significantly detected members of the synchrotron-dominated population are associated with sources in previously published radio catalogs. Some of the dust-dominated sources are associated with nearby (z << 1) galaxies whose dust emission is also detected by the Infrared Astronomy Satellite. However, most of the bright, dust-dominated sources have no counterparts in any existing catalogs. We argue that these sources represent the rarest and brightest members of the population commonly referred to as submillimeter galaxies (SMGs). Because these sources are selected at longer wavelengths than in typical SMG surveys, they are expected to have a higher mean redshift distribution and may provide a new window on galaxy formation in the early universe.
Past studies have suggested that long-duration γ-ray bursts have a 'standard' energy of Eγ 1051 erg in the ultra-relativistic ejecta, after correcting for asymmetries in the explosion ('jets'). But a ...group of sub-energetic bursts, including the peculiar GRB980425 associated with the supernova SN1998bw (Eγ 1048 erg), has recently been identified. Here we report radio observations of GRB030329 that allow us to undertake calorimetry of the explosion. Our data require a two-component explosion: a narrow (5° opening angle) ultra-relativistic component responsible for the γ-rays and early afterglow, and a wide, mildly relativistic component that produces the radio and optical afterglow more than 1.5 days after the explosion. The total energy release, which is dominated by the wide component, is similar to that of other γ-ray bursts, but the contribution of the γ-rays is energetically minor. Given the firm link of GRB030329 with SN2003dh, our result indicates a common origin for cosmic explosions in which, for reasons not yet understood, the energy in the highest-velocity ejecta is extremely variable.
We report the detection of CO(1-0) line emission in the bright, lensed star-forming galaxies SPT-S 233227−5358.5 (z = 2.73) and SPT-S 053816−5030.8 (z = 2.78), using the Australia Telescope Compact ...Array. Both galaxies were discovered in a large-area millimetre survey with the South Pole Telescope (SPT) and found to be gravitationally lensed by intervening structures. The measured CO intensities imply galaxies with molecular gas masses of (3.2 ± 0.5) × 1010(μ/15)−1(X
CO/0.8) and (1.7 ± 0.3) × 1010(μ/20)−1(X
CO/0.8) M, and gas depletion time-scales of 4.9 × 107(X
CO/0.8) and 2.6 × 107(X
CO/0.8) yr, respectively, where μ corresponds to the lens magnification and X
CO is the CO luminosity to gas mass conversion factor. In the case of SPT-S 053816−5030.8, we also obtained significant detections of the rest-frame 115.7 and 132.4 GHz radio continuum. Based on the radio-to-infrared spectral energy distribution and an assumed synchrotron spectral index, we find that 42 ± 10 and 55 ± 13 per cent of the flux at rest-frame 115.7 and 132.4 GHz arises from free-free emission. We find a radio-derived intrinsic star formation rate of 470 ± 170 M yr−1, consistent within the uncertainties with the infrared estimate. Based on the morphology of this object in the source plane, the derived gas mass and the possible flattening of the radio spectral index towards low frequencies, we argue that SPT-S 053816−5030.8 exhibits properties compatible with a scaled-up local ultraluminous infrared galaxy.
We revisit the discovery outburst of the X-ray transient XTE J1550−564 during which relativistic jets were observed in 1998 September, and review the radio images obtained with the Australian Long ...Baseline Array, and light curves obtained with the Molonglo Observatory Synthesis Telescope and the Australia Telescope Compact Array. Based on Hi spectra, we constrain the source distance to between 3.3 and 4.9 kpc. The radio images, taken some 2 d apart, show the evolution of an ejection event. The apparent separation velocity of the two outermost ejecta is at least 1.3c and may be as large as 1.9c; when relativistic effects are taken into account, the inferred true velocity is ≥ 0.8c. The flux densities appear to peak simultaneously during the outburst, with a rather flat (although still optically thin) spectral index of −0.2.
Sarcopenia, myosteatosis and obesity in cancer may confer negative clinical outcomes, but their prevalence and impact among patients with retroperitoneal and trunk soft tissue sarcoma have not been ...systematically studied. The aim of this study was to determine body composition among patients with retroperitoneal and trunk sarcoma, and assess impact on operative and oncologic outcomes.
Consecutive patients undergoing treatment with curative intent from 2009 to 2019 were studied. Subcutaneous fat area and visceral fat areas, intramuscular adipose, lean body mass and fat mass were determined at diagnosis by CT at L3. Univariable and multivariable linear, logistic and Cox proportional hazards regression were performed.
95 patients (43.2% retroperitoneal, 48.4% trunk, 46.3% multivisceral resection) were studied. Visceral obesity was evident in 47.4%. Postoperative morbidity occurred in 25.9%, with preoperative radiotherapy (OR10.53 95% CI 1.08–102.39, P = 0.042) and fat mass (OR1.41 1.12–1.79, P = 0.004) independently predictive on multivariable analysis, while intramuscular adipose independently predicted inpatient LOS (P < 0.001), wound infection (P = 0.024, OR1.20 1.02–1.40) and major postoperative morbidity (P = 0.027, OR1.15 1.02–1.31). Increasing fat mass, subcutaneous fat area and intramuscular adipose were associated with greater tumor size (all P < 0.01), while intramuscular adipose predicted disease progression during neoadjuvant therapy (P = 0.024), and independently predicted disease specific survival (DSS) (P = 0.005, HR1.11 1.03–1.20) and overall survival (OS) on multivariable analysis (P < 0.001, HR1.19 1.08–1.31).
Visceral obesity is common in retroperitoneal and trunk sarcoma, and measures of adiposity are associated with adverse operative, but not oncologic outcomes. Myosteatosis is independently associated with postoperative morbidity and adverse oncologic outcomes. Body composition may represent a marker of risk among patients with retroperitoneal and trunk sarcoma.
•The impact of sarcopenia, myosteatosis and obesity on patients with soft tissue sarcoma is poorly understood.•Nutritional status is a key marker of peri-operative and oncologic risk among patients with retroperitoneal and trunk soft tissue sarcoma.•Increased adiposity was associated with postoperative morbidity, with total fat mass an independent predictor of complications.•Myosteatosis was associated with increased postoperative morbidity and adverse long-term oncologic outcomes.•Comprehensive nutritional assessment may contribute to optimization of care for patients with this complex attritional group of cancers
Magnetic resonance follow-through (MRFT) is a new cross-sectional imaging modality with the potential to accurately stage ileal Crohn's disease (CD), while avoiding ionizing radiation and the ...discomfort associated with enteroclysis. We aimed to assess the reliability of this technique in assessing the extent and activity of ileal CD, and to assess its influence on subsequent management.
Out of a total of 342 patients undergoing MRFT between 2004 and 2008, 221 were performed in 191 patients with confirmed CD. Case notes were reviewed in detail with documentation of all investigations pre- and post-MRFT. Agreement between inflammatory markers, histopathology, and MRFT findings was determined.
Overall, 116/221 (52.5%) of MRFTs showed active ileal CD, and 76/221 (34.4%) quiescent CD, while 29/221 (13.1%) were suboptimal. Overall, 66 strictures and 18 fistulae were identified. There was substantial agreement between active ileal CD on MRFT and histopathology (n = 59; kappa = 0.66; P = 0.0006; sensitivity 85.1%, specificity 85.7%) and fecal calprotectin (n = 14; kappa = 0.72; P = 0.047), while C-reactive protein (CRP) showed moderate agreement (n = 107; kappa = 0.402; P = 0.00028). Management was influenced by MRFT reports following active (52/84, 62% treated medically) or quiescent (48/62, 77.4% managed conservatively) disease. Fibrotic strictures were predominantly treated surgically (7/14, 50%). In all, 13/32 (40.6%) patients with inflammatory ileal strictures required surgery, mostly due to steroid-resistant disease. Overall, 75 MR findings were documented in 221 MRFTs, including 1 renal cancer.
MRFT provides accurate information on ileal CD activity, with close agreement to inflammatory markers and histopathology. It represents a substantial advance in the staging of CD, while avoiding painful enteroclysis and radiation exposure in young patients.
The Australia Telescope Compact Array (ATCA) has been used at 1.38 and 2.38 GHz to survey seven southern Abell clusters of galaxies with high X-ray luminosities: A2746, A2837, A3126, A3216, A3230, ...A3827 and A3836. The clusters have also been surveyed at 0.843 GHz with the Molonglo Observatory Synthesis Telescope (MOST). We have listed a complete 1.38-GHz sample of 149 radio sources within the Abell circles centred on their X-ray centroids. We compare their identification fractions, emitted 1.38 GHz and optical powers, radio spectral indices and radial variation in projected source density with those of the radio-selected samples of Slee, Roy & Andernach. We compare our fractional radio luminosity function with that of the radio-selected samples of Ledlow & Owen and Slee et al. Three significant differences are noted between X-ray and radio-selected samples of clusters: (1) the X-ray sample has an excess of flat-spectrum radio sources; (2) the fractional radio luminosity function for the Fanaroff–Riley I (FR I) sources in the X-ray selected sample is much steeper, implying that fewer of their cluster galaxies become hosts for the stronger FR I radio galaxies; (3) a complete absence of Fanaroff–Riley II (FR II) radio galaxies in the X-ray selected sample. The average excess projected density of radio sources near our cluster centres is ∼five times the background source density.
Cutaneous neuroendocrine tumours are rare and aggressive tumours associated with advanced age and immunosuppression. They are typically characterised by a high rate of local recurrence and nodal ...disease. The presence of a mixed squamous cell component is rare. These tumours are uncommonly found on the hand. We present a case and histological images of a 78-year-old woman with a primary CK20 negative TTF-1 positive cutaneous neuroendocrine tumour with squamous dedifferentiation arising from the fifth digit with axillary metastasis showing a mixed phenotype. Initial biopsy of the lesion was positive for chromogranin, synaptophysin and TTF-1, but negative for CK20, Melan-A and S100. After CT of the thorax abdomen and pelvis and octreotide single positron emission CT demonstrated a 15 mm axillary metastasis and no evidence of distal disease, our patient underwent an amputation of the affected digit and an axillary lymph node dissection. She is currently awaiting adjuvant chemoradiotherapy. Only two cases are reported in the literature to have mixed squamous/neuroendocrine features. We present the first case which is CK20 negative and TTF-1 positive.
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