Objectives
Sinonasal inverted papilloma (IP) has several unfavourable characteristics and therefore requires careful monitoring. The goal of this study was to identify whether serum squamous cell ...carcinoma antigen (SCCa) could predict IP recurrence.
Design
A retrospective cohort study.
Setting
Department of otolaryngology/head and neck surgery, Erasmus Medical Centre, Rotterdam, the Netherlands.
Participants
One hundred and thirty patients with IP treated at our centre with SCCa measurements available were included.
Main outcome measurements
Follow‐up of patients with IP since 2005, recurrence was defined as new disease within primary localisation at least 3 months after adequate surgical removal. We analysed the association between IP recurrence and serum SCCa values measured preoperatively, postoperatively and during follow‐up.
Results
Preoperative SCCa values or values measured during follow‐up were not associated with risk of recurrence. Postoperative SCCa was positively associated with the risk of recurrence (P < 0.001). Postoperative SCCa had a good discriminative ability for the identification of recurrence with an area under the curve of 80.9%.
Conclusion
Postoperative SCCa is strongly associated with risk of recurrence. This might help the surgeon in the postoperative setting by identifying high‐risk patients and planning follow‐up strategy tailored to the individual patient.
We present the first 7-mm observations of two high-redshift, Lyα-bright radio galaxies (MRC 2104−242 and MRC 0943−242) performed with the 2 × 2 GHz instantaneous bandwidth of the Compact Array ...Broadband Backend (CABB) at the Australia Telescope Compact Array (ATCA). The aim was to search for 12CO(1−0) emission in these systems and test the millimetre capabilities of CABB for performing spectral line observations at high redshifts. We show that the stable band and enhanced velocity coverage of CABB, combined with hybrid array configurations, provide the ATCA with excellent 7-mm capabilities that allow reliable searches for the ground transition of CO at high redshifts. In this paper we explicitly discuss the calibration procedures used to reach our results. We set a firm upper limit to the mass of molecular gas in MRC 2104−242 (z= 2.5) of
M⊙. For MRC 0943−242 (z= 2.9) we derive an upper limit of
M⊙. We also find a tentative 3σ CO detection in the outer part of the giant Lyα halo that surrounds MRC 0943−242. The 30-33 GHz radio continuum of MRC 2104−242 and MRC 0943−242 is reliably detected. Both radio sources show a spectral index of α≈−1.5 between 1.4 and 30 GHz, with no evidence for spectral curvature within this range of frequencies.
Background
The importance and value of the principles of evidence‐based practice (EBP) in the decision‐making process is recognized by speech–language therapists (SLTs) worldwide and as a result ...curricula for speech–language therapy students incorporated EBP principles. However, the willingness actually to use EBP principles in their future profession not only depends on EBP knowledge and skills, but also on self‐efficacy and task value students perceive towards EBP.
Aims
To investigate the relation between EBP knowledge and skills, and EBP self‐efficacy and task value in different year groups of Dutch SLT students.
Methods & Procedures
Students from three year groups filled in a tool that measured EBP knowledge and skills: the Dutch Modified Fresno (DMF). EBP self‐efficacy and task value were assessed by using a 20‐item questionnaire. Both tools were validated for this population. Mean scores for the three year groups were calculated and tested for group differences using a one‐way analysis of variance (ANOVA) with a post‐hoc Games–Howell procedure. With a multiple linear regression technique it was assessed whether EBP self‐efficacy and task value predict learning achievement scores on the DMF. Other possible predictors included in the model were: level of prior education, standard of English, having had mathematics in prior education and the SLT study year.
Outcome & Results
A total of 149 students filled in both measurement tools. Mean scores on EBP knowledge and skills were significantly different for the three year groups, with students who were further along their studies scoring higher on the DMF. Mean scores on the EBP self‐efficacy and task value questionnaire were the same for the three year groups: all students valued EBP positive but self‐efficacy was low in all groups. Of the possible predictors, only the year in which students study and EBP self‐efficacy were significant predictors for learning achievements in EBP.
Conclusions & Implications
Despite a significant increase in EBP knowledge and skills over the years as assessed by the DMF, the integrated EBP curriculum did not raise levels of EBP self‐efficacy and task value. This lack of feeling competent might have an impact on students’ willingness actually to use EBP. In curricula, therefore, there should be a focus on how to raise EBP self‐efficacy in SLT students. This goes even beyond the educational department because a professional culture in which professionals are competent and confident EBP users would have a positive effect on EBP self‐efficacy in students.
Context. Deriving physical parameters from gamma-ray burst (GRB) afterglow observations remains a challenge, even 20 years after the discovery of afterglows. The main reason for the lack of progress ...is that the peak of the synchrotron emission is in the sub-mm range, thus requiring radio observations in conjunction with X-ray/optical/near-infrared data in order to measure the corresponding spectral slopes and consequently remove the ambiguity with respect to slow vs. fast cooling and the ordering of the characteristic frequencies. Aims. We have embarked on a multifrequency, multi-epoch observing campaign to obtain sufficient data for a given GRB that allows us to test the simplest version of the fireball afterglow model. Methods. We observed GRB 151027B, the 1000th Swift-detected GRB, with GROND in the optical–near-IR, ALMA in the sub-millimeter, ATCA in the radio band; we combined this with public Swift/XRT X-ray data. Results. While some observations at crucial times only return upper limits or surprising features, the fireball model is narrowly constrained by our data set, and allows us to draw a consistent picture with a fully determined parameter set. Surprisingly, we find rapid, large-amplitude flux density variations in the radio band which are extreme not only for GRBs, but generally for any radio source. We interpret them as scintillation effects, though their extreme nature requires the scattering screen to be at a much smaller distance than usually assumed, multiple screens, or a combination of the two. Conclusions. The data are consistent with the simplest fireball scenario for a blast wave moving into a constant-density medium, and slow-cooling electrons. All fireball parameters are constrained at or better than a factor of 2, except for the density and the fraction of the energy in the magnetic field which has a factor of 10 uncertainty in both directions.
Objectives
Identification at time of diagnosis of those vestibular schwannomas that will not grow.
Design
Retrospective cohort study of consecutive patients diagnosed with a sporadic vestibular ...schwannoma that were entered in the wait‐and‐scan protocol.
Setting
Academic referral centre.
Participants
The study group contained 155 patients with a sporadic vestibular schwannoma first seen in the full 8‐year period 2000–2007: continual wait‐and‐scan (n = 89) and initial wait‐and‐scan until intervention (n = 66).
Main outcome measures
Tumour growth, defined as more than 2 mm linear difference in any plane between the diagnostic MRI‐scan and the last available scan, was related to clinical parameters at diagnosis: localisation of the tumour (solely intracanalicular versus cisternal extension), sudden sensorineural hearing loss, sensorineural hearing loss longer than 2 years and vertigo/instability.
Results
Hearing loss longer than 2 years and an entirely intracanalicular localisation were associated with no tumour growth by univariate and multivariate Cox analysis. Combining both factors at time of diagnosis resulted in a group with low risk of growth (n = 36, median follow‐up of 6.2 years) with a Hazard Ratio for growth of 0.37 (95% CI, 0.19–0.69). This subgroup is about 25% of the wait‐and‐scan population. Thirty‐one percent showed growth, while in the remaining higher risk group of 119 patients 62% showed growth. For the growing schwannomas, the median time for growth becoming manifest is 1.9 years after diagnostic MRI.
Conclusions
In this study on vestibular schwannoma patients that start in a wait‐and‐scan protocol, about a quarter may be set apart having a low risk for growth. These patients at diagnosis combine a history of hearing loss longer than 2 years and a fully intracanalicular schwannoma. They seem to be not needed yearly MRI checks.
Context. The nature and evolutionary properties of the faint radio population, responsible for the steepening observed in the 1.4 GHz source counts below 1 milliJy, are not yet entirely clear. Radio ...spectral indices may help to constrain the origin of the radio emission in such faint radio sources and may be fundamental in understanding eventual links to the optical light. Aims. We study the spectral index behaviour of sources that were found in the 1.4 GHz ATESP survey (Prandoni et al. 2000a, A&AS, 146, 31; 2000b, A&AS, 146, 41), considering that the ATESP is one of the most extensive sub-mJy surveys existing at present. Methods. Using the Australia Telescope Compact Array we observed at 5 GHz part of the region covered by the sub-mJy ATESP survey. In particular we imaged a one square degree area for which deep optical imaging in UBVRIJK is available. In this paper we present the 5 GHz survey and source catalogue, we derive the 5 GHz source counts and we discuss the 1.4-5 GHz spectral index properties of the ATESP sources. The analysis of the optical properties of the sample will be the subject of a following paper. Results. The 5 GHz survey has produced a catalogue of 111 radio sources, complete down to a (6\sigma) limit S_{\rm lim}(5 similar to {\rm GHz}) \sim 0.4 mJy. We take advantage of the better spatial resolution at 5 GHz (2\arcsec compared to 8\arcsec at 1.4 GHz) to infer radio source structures and sizes. The 5 GHz source counts derived by the present sample are consistent with those reported in the literature, but improve significantly the statistics in the flux range 0.4\la S_{5 similar to {\rm GHz}}\la 1 mJy. The ATESP sources show a flattening of the 1.4-5 GHz spectral index with decreasing flux density, which is particularly significant for the 5 GHz selected sample. Such a flattening confirm previous results coming from smaller samples and is consistent with a flattening of the 5 GHz source counts occurring at fluxes \la0.5 mJy.
Aims. With the afterglow of GRB 100621A being the brightest detected so far in X-rays, and superb GROND coverage in the optical/near-infrared during the first few hours, an observational verification ...of basic fireball predictions seemed possible. Methods. In order to constrain the broad-band spectral energy distribution of the afterglow of GRB 100621A, dedicated observations were performed in the optical/near-infrared with the 7-channel Gamma-Ray Burst Optical and Near-infrared Detector (GROND) at the 2.2 m MPG/ESO telescope, in the sub-millimeter band with the large bolometer array LABOCA at APEX, and at radio frequencies with ATCA. Utilizing also Swift X-ray observations, we attempt an interpretation of the observational data within the fireball scenario. Results. The afterglow of GRB 100621A shows a very complex temporal and spectral evolution. We identify three different emission components, the most spectacular one causing a sudden intensity jump about one hour after the prompt emission. The spectrum of this component is much steeper than the canonical afterglow. We interpret this component using a two-shell collision prescription after the first shell has been decelerated by the circumburst medium. We use the fireball scenario to derive constraints on the microphysical parameters of the first shell. Long-term energy injection into a narrow jet seems to provide an adequate description. Another noteworthy result is the large (AV = 3.6 mag) line-of-sight host extinction of the afterglow in an otherwise extremely blue host galaxy. Conclusions. Some GRB afterglows have shown complex features, and that of GRB 100621A is another good example. Yet, detailed observational campaigns of the brightest afterglows promise to deepen our understanding of the formation of afterglows and the subsequent interaction with the circumburst medium.
Obsessive–compulsive disorder (OCD) has been related to altered mechanisms of action monitoring and target detection, and it has been hypothesized that hyperactive striatal–cortical circuits ...constitute the underlying pathophysiology. This study used event-related brain potentials (ERPs) to explore this hypothesis. A choice reaction time experiment was carried out in a group of OCD patients and a normal comparison group. The P3b component of the ERP to targets was taken as an indicator of the target-evaluation process and the response-locked error-related negativity (ERN) served as an indicator of action monitoring. We hypothesized that the OCD group would show a shortened P3b latency and an amplitude-enhanced ERN. Consistent with our expectations, the P3b latency was shorter and the ERN amplitude was higher in the OCD group. Unexpectedly, we also observed a prolonged ERN latency in the OCD group and a more posterior topography of this component. The data provide partial support for the hypothesis of a hyperactive neural network in OCD. In addition the disorder must involve pathophysiological processes that are presumably related to other aspects of its complex and heterogeneous clinical hallmarks.
SGR 1833−0832 was discovered on 2010 March 19, thanks to the Swift detection of a short hard X-ray burst and follow-up X-ray observations. Since then, it was repeatedly observed with Swift, Rossi ...X-ray Timing Explorer and XMM-Newton. Using these data, which span about 225 d, we studied the long-term spectral and timing characteristics of SGR 1833−0832. We found evidence for diffuse emission surrounding SGR 1833−0832, which is most likely a halo produced by the scattering of the point-source X-ray radiation by dust along the line of sight, and we show that the source X-ray spectrum is well described by an absorbed blackbody, with temperature kT∼ 1.2 keV and absorbing column N
H= (10.4 ± 0.2) × 1022 cm−2, while different or more complex models are disfavoured. The source persistent X-ray emission remained fairly constant at ∼3.7 × 10−12 erg cm−2 s−1 for the first ∼20 d after the onset of the bursting episode, then it faded by a factor of ∼40 in the subsequent ∼140 d, following a power-law trend with index α≃−0.5. We obtained a phase-coherent timing solution with the longest baseline (∼225 d) to date for this source which, besides period P= 7.565 4084(4) s and period derivative
s s−1, includes higher order period derivatives. We also report on our search of the counterpart to the soft gamma-ray repeater (SGR) at radio frequencies using the Australia Telescope Compact Array and the Parkes Radio Telescope. No evidence for radio emission was found, down to flux densities of 0.9 mJy (at 1.5 GHz) and 0.09 mJy (at 1.4 GHz) for the continuum and pulsed emissions, respectively, consistently with other observations at different epochs. Finally, the analysis of the field of PSR B1830−08 (J1833−0827), which was serendipitously imaged by the XMM-Newton observations, led to the discovery of the X-ray pulsar wind nebula generated by this 85-ms radio pulsar. We discuss its possible association with the unidentified TeV source HESS J1834−087.
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