ABSTRACT
We examine the distribution of radio emission from ∼42 000 quasars from the Sloan Digital Sky Survey, as measured in the LOFAR Two-metre Sky Survey (LoTSS). We present a model of the radio ...luminosity distribution of the quasars that assumes that every quasar displays a superposition of two sources of radio emission: active galactic nuclei (jets) and star formation. Our two-component model provides an excellent match to the observed radio flux density distributions across a wide range of redshifts and quasar optical luminosities; this suggests that the jet-launching mechanism operates in all quasars but with different powering efficiency. The wide distribution of jet powers allows for a smooth transition between the ‘radio-quiet’ and ‘radio-loud’ quasar regimes, without need for any explicit bimodality. The best-fitting model parameters indicate that the star formation rate of quasar host galaxies correlates strongly with quasar luminosity and also increases with redshift at least out to z ∼ 2. For a model where star formation rate scales as $L_{\rm bol}^{\alpha } (1+z)^{\beta }$, we find α = 0.47 ± 0.01 and β = 1.61 ± 0.05, in agreement with far-infrared studies. Quasars contribute ≈0.15 per cent of the cosmic star formation rate density at z = 0.5, rising to 0.4 per cent by z ∼ 2. The typical radio jet power is seen to increase with both increasing optical luminosity and black hole mass independently, but does not vary with redshift, suggesting intrinsic properties govern the production of the radio jets. We discuss the implications of these results for the triggering of quasar activity and the launching of jets.
Entamoeba histolytica is a protozoan parasite that causes colitis and liver abscesses. Several Entamoeba species and strains with differing levels of virulence have been identified. E. histolytica ...HM-1:IMSS is a virulent strain, E. histolytica Rahman is a nonvirulent strain, and Entamoeba dispar is a nonvirulent species. We used an E. histolytica DNA microarray consisting of 2,110 genes to assess the transcriptional differences between these species/strains with the goal of identifying genes whose expression correlated with a virulence phenotype. We found 415 genes expressed at lower levels in E. dispar and 32 genes with lower expression in E. histolytica Rahman than in E. histolytica HM-1:IMSS. Overall, 29 genes had decreased expression in both the nonvirulent species/strains than the virulent E. histolytica HM-1:IMSS. Interestingly, a number of genes with potential roles in stress response and virulence had decreased expression in either one or both nonvirulent Entamoeba species/strains. These included genes encoding Fe hydrogenase (9.m00419), peroxiredoxin (176.m00112), type A flavoprotein (6.m00467), lysozyme (6.m00454), sphingomyelinase C (29.m00231), and a hypothetical protein with homology to both a Plasmodium sporozoite threonine-asparagine-rich protein (STARP) and a streptococcal hemagglutinin (238.m00054). The function of these genes in Entamoeba and their specific roles in parasite virulence need to be determined. We also found that a number of the non-long-terminal-repeat retrotransposons (EhLINEs and EhSINEs), which have been shown to modulate gene expression and genomic evolution, had lower expression in the nonvirulent species/strains than in E. histolytica HM-1:IMSS. Our results, identifying expression profiles and patterns indicative of a virulence phenotype, may be useful in characterizing the transcriptional framework of virulence.
Metastasising cells express the intermediate filament protein vimentin, which is used to diagnose invasive tumours in the clinic. We aimed to clarify how vimentin regulates the motility of ...metastasising fibroblasts. STED super-resolution microscopy, live-cell imaging and quantitative proteomics revealed that oncogene-expressing and metastasising fibroblasts show a less-elongated cell shape, reduced cell spreading, increased cell migration speed, reduced directionality, and stronger coupling between these migration parameters compared to normal control cells. In total, we identified and compared 555 proteins in the vimentin interactome. In metastasising cells, the levels of keratin 18 and Rab5C were increased, while those of actin and collagen were decreased. Inhibition of HDAC6 reversed the shape, spreading and migration phenotypes of metastasising cells back to normal. Inhibition of HDAC6 also decreased the levels of talin 1, tropomyosin, Rab GDI β, collagen and emilin 1 in the vimentin interactome, and partially reversed the nanoscale vimentin organisation in oncogene-expressing cells. These findings describe the changes in the vimentin interactome and nanoscale distribution that accompany the defective cell shape, spreading and migration of metastasising cells. These results support the hypothesis that oncogenes can act through HDAC6 to regulate the vimentin binding of the cytoskeletal and cell-extracellular matrix adhesion components that contribute to the defective motility of metastasising cells.
Stereotactic radiosurgery (SRS) is an alternative to surgery or whole brain radiotherapy for the control of single or multiple brain metastases in patients with breast cancer. To date, there is no ...clear consensus on factors that might predict overall survival following SRS. The aim of this study was to assess the overall survival of breast cancer patients with brain metastases treated with SRS at a single centre and to examine the factors that might influence survival.
A retrospective analysis of consecutive patients with breast cancer and brain metastases, considered suitable for SRS by the regional neuro-oncology multidisciplinary team. All patients were treated at a single National Health Service centre.
In total, 91 patients received SRS between 2013 and 2017, of whom 15 (16.5%) were alive at the time of analysis. The median overall survival post-SRS was 15.7 months (interquartile range 7.7–23.8 months) with no significant effect of age on survival (67 patients ≤ 65 years, 16.3 months; 26 patients > 65 years, 11.4 months, P = 0.129). The primary tumour receptor status was an important determinant of outcome: 31 oestrogen receptor positive (ER+)/human epidermal growth factor receptor 2 negative (HER2–) patients had a median overall survival of 13.8 months, 14 ER+/HER2+ patients had a median overall survival of 21.4 months, 30 ER–/HER2+ patients had a median overall survival of 20.4 months and 16 patients with triple negative breast cancer (TNBC) had a median overall survival of 8.5 months. A larger total volume of tumour treated (>10 cm3), but not the number of individual metastases treated, was associated with worse survival (P = 0.0002) in this series. Patients with stable extracranial disease at the time of SRS had improved overall survival compared with those with progressive extracranial disease (30 patients stable extracranial disease overall survival = 20.1 months versus 33 patients progressive extracranial disease overall survival = 11.4 months; P = 0.0011). Seventeen patients had no extracranial disease at the time of SRS, with a median overall survival of 13.1 months.
This single-centre series of consecutive patients with brain metastases from breast cancer, treated with SRS, had a similar overall survival compared with previous studies of SRS. TNBC and ER+/HER2– histology, metastatic volumes >10 cm3 and progressive extracranial disease at the time of SRS were associated with worse survival.
•There is improving overall survival in breast cancer patients with brain metastases treated with stereotactic radiosurgery.•Factors influencing survival post-stereotactic radiosurgery are receptor status, systemic disease control and volume of metastases treated.•Patients with disease limited to the CNS had worse survival than those with stable extracranial disease, suggesting a possible role for systemic therapy in this patient subset.
Coal seam (CS) gas operations coproduce water with gas from confined CS aquifers. This CS water represents a potential agricultural resource if the water is able to be chemically amended to comply ...with management guidelines. Stoichiometric quantities of sulphur and gypsum amendments can be used to neutralise the alkalinity and reduce the sodicity of CS water respectively. These amendments can either be mixed in-line at a water treatment plant or applied directly to land prior to the application of CS water (a practice termed land amendment irrigation - LAI). This study compared the efficacy of LAI with in-line chemical amendment of CS water and irrigation with non-saline, non-sodic and non-alkaline (good quality) water under field conditions in southern Queensland. Soil chemical properties, soluble Ca, Mg, K, Na, electrical conductivity (EC), pH, chloride and alkalinity, as well as saturated hydraulic conductivity were measured to determine the impact of the irrigation treatments on soil chemical and physical conditions. Irrigation of lucerne pasture using solid-set sprinklers applied a total of 6.7 ML/ha of each treatment irrigation water to the experimental plots over a 10-month period. Alkalinity was neutralised using LAI, with no increase in soil alkalinity observed. Soil sodicity did not exceed threshold electrolyte concentration values under either CS water irrigation treatment. Soil chemical and physical properties were comparable for both LAI and in-line chemical amendment of CS water. Soil saturated hydraulic conductivity was maintained under all irrigation treatments. Results showed that the constrained capacity of the irrigation system was unable to meet crop evapotranspiration demand. This resulted in accumulation of salt within the root-zone under the CS water treatments compared to the good quality water treatment. LAI successfully chemically amended Bowen Basin CS water facilitating its beneficial use for agricultural irrigation.
•The first Australian field demonstration of successful land amendment irrigation.•Gypsum/sulphur land-application effectively treated sodic-alkaline irrigation.•In-line water treatment was comparable to land amendment irrigation.•Treatment magnitude provided adequate buffering in lieu of a leaching fraction.
Strongyloides stercoralis is a parasitic roundworm causing chronic infection that is endemic in Southeast Asia. Vietnam veterans are considered to be at high risk of Strongyloides infection. The ...prevalence of persistent infection in this group is unknown. This study aimed to establish the seropositivity rate of Strongyloides antibodies in South Australian Vietnam veterans and to identify the most reported symptoms within the seropositive group.
This cross‐sectional study recruited 309 veterans who had served in Vietnamese territory between 1962 and 1975 and were currently resident in South Australia. Participants completed a self‐administered questionnaire examining demographics, deployment, somatic symptoms and depression. Venous blood was collected for Strongyloides serology and eosinophil count. Participants who demonstrated positive Strongyloides serology underwent faecal microscopy for parasites.
A total of 309 participants were recruited and 256 completed the questionnaire. Strongyloides seropositivity was demonstrated in 29 of 249 participants (11.6%). No participant had Strongyloides larvae detected by faecal microscopy. On multivariate analysis, only dermatological symptoms were associated with positive serology (OR 4.84, 95%CI 1.31–17.92, p‐value 0.01).
This study found a high seroprevalence (11.6%) of Strongyloides antibodies within the Vietnam veteran community in South Australia. Seropositivity was associated with increased likelihood of dermatological symptoms.
Post‐deployment screening and eradication therapy for Strongyloides should be offered to ADF staff after service in Strongyloides‐endemic areas. This should include those veterans who left the service many years ago.
The American College of Radiology's (ACR) Nuclear Medicine and PET Accreditation Programs evaluate qualifications of personnel, equipment, image quality, and quality control measures. It is believed ...that these are primary factors that impact the quality of patient imaging. The ACR accreditation allows facilities to critique and improve their practices as part of their preparation for the accreditation evaluation process. The goals of the ACR Nuclear Medicine and PET Accreditation Programs are improvement in the quality of imaging, provision of educational information by raising awareness of imaging issues, and the recognition of imaging facilities which meet program objectives. This presentation will outline the program requirements, highlighting some of the common pitfalls that may cause deficiencies in both the clinical and phantom submissions.
Educational Objectives:
1. General information describing the ACR Accreditation Programs.
2. Information about the Diagnostic Modality Accreditation Programs.
3. Specific information about the ACR Nuclear Medicine and PET Accreditation Program, to include the application process, clinical images submission and quality control requirements.
This essay contrasts scholarship on printed authority within buccaneer ethnographies, contemporary apologetics for colonial enterprise, and the role of publicity in the delineation of piracy within ...print to ask: ‘when is a pirate not a pirate?’. Beginning with the ethnographies relating to the buccaneers’ crossing of the Isthmus of Darien during the ‘Pacific Adventure’ (1679–1682), this paper describes how the buccaneers escaped prosecution through their literary materials and became socially rehabilitated as credible explorers. Drawing on materials which highlight the diverse readings of piracy within the different ‘news-cultures’ and maritime traditions which existed in the Atlantic archipelago, this paper develops an argument for a ‘popular’ conception and interpretation of piracy within publicity and periodical print which reflects its utility within competing political and maritime enterprises. Using contrasting examples of the negotiation and renegotiation of what constituted ‘piracy’ within the promotion of the attempted colonisation of the Isthmus of Darien by the Company of Scotland (1696–1700), and the literary campaign which surrounded the trial of the crew of the Worcester for piracy in 1705, this essay argues for the role of ‘public opinion’ and popular print culture in the making and unmaking of pirates in early modern anglophone print.
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