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A MUSE spectro-imaging study of the Th 28 jet: Precession in the inner jet
No full textContext. Th 28 is a Classical T Tauri star in the Lupus 3 cloud that drives an extended bipolar jet. Previous studies of the inner jet identified signatures of rotation around the outflow axis, a key result for theories of jet launching. Thus this is an important source in
which to investigate the poorly understood jet launching mechanism. Aims. In this study we investigate the morphology and kinematics of the Th 28 micro-jets, with the aim of characterising their structure and outflow activity, using optical integral-field spectroscopy observations obtained with VLT/MUSE.
Methods. We use spectro-imaging and position–velocity maps to investigate the kinematic and morphological features of the jet and to obtain a catalogue of emission lines in which the jet is visible. A Lucy-Richardson deconvolution procedure is used to differentiate the structure of the inner micro-jet region in selected emission lines. Spatial profiles extracted perpendicular to the jet axis are fitted to investigate the jet width, opening angle, and the evolution of the jet axis.
Results. We confirm the previously identified knot HHW2 within the red-shifted jet and identify three additional knots in each lobe for the first time. We also find [O III]λ5007 emission from the blue-shifted micro-jet, including the knot closest to the star. Proper
motions for the innermost knots on each side are estimated to be 0. 0035 yr−1 and 0. 0047 yr−1 for the red- and blue-shifted jets, respectively. Based on this we show that new knots are ejected on an approximate timescale of 10–15 yr. Gaussian fitting to the jet axis centroids shows a point-symmetric wiggle within the inner portion of both micro-jets, indicating precession of the jet. We use the jet shape to measure a precession period of 8 yr, with a half-opening angle β < 0.6 ◦ . This precession may provide an alternative explanation for the rotation signatures previously reported.
Conclusions. We find that these parameters are compatible with precession due to a brown dwarf companion orbiting at a separation of ≤0.3 au. Further observations with higher spatial resolution may help to clarify the source of this precession
Geographies of authority
No full textWe propose a geography that pluralizes the sites, practices and politics of authority. We defend an approach
that tracks less perceptible forms of authority emerging through everyday micropolitics and experimental
practices. In contrast to dominant definitions of authority as institutionalized legitimate power, we define
authority as a relation of guidance emerging from recognition of inequalities in access to truth, experience or objectivity. Analysing four intersecting areas of authority (algorithmic, experiential, expert and participatory authority), we propose analyses grounded in political aesthetics that trace authority’s affective force, and its role in disclosing and contesting the common
When Does the Lorenz 1963 Model Exhibit the Signal‐To‐Noise Paradox?
No full textSeasonal prediction systems based on Earth System Models exhibit a lower proportion of predictable signal to unpredictable noise than the actual world. This puzzling phenomena has been widely referred to as the signal-to-noise paradox (SNP). Here, we investigate the SNP in a conceptual
framework of a seasonal prediction system based on the Lorenz, 1963 Model (L63). We show that the SNP is not apparent in L63, if the uncertainty assumed for the initialization of the ensemble is equal to the uncertainty in the starting conditions. However, if the uncertainty in the initialization overestimates the uncertainty in the starting conditions, the SNP is apparent. In these experiments the metric used to quantify the SNP also shows a clear lead-time dependency on sub-seasonal timescales. We therefore, formulate the alternative hypothesis to previous studies that the SNP could also be related to the
magnitude of the initial ensemble spread
Book review: Cities and communities beyond COVID-19: how local leadership can change our future for the better
No full textThe abstract is included in the text
Drug delivery formulation impacts cyclosporine efficacy in a humanised mouse model of acute graft versus host disease
No full textAcute graft versus host disease (aGvHD) is an allogeneic T cell mediated disease which manifests as a severe inflammatory disease affecting multiple organs including the liver, skin, lungs and gastrointestinal tract. Existing prophylactic and therapeutic approaches in aGvHD include the use of cyclosporine A (CyA), however the currently approved CyA formulations which were designed to optimise systemic CyA bioavailability can have a number of side effects including nephrotoxicity as well as the potential to attenuate the beneficial Graft-versus-Leukemia (GvL) effect. An added complication with CyA is that it has a narrow therapeutic window, and following oral administration is absorbed only from the small intestine, with variable cytochrome P450 metabolism contributing to intra- and inter-patient variability. This study sought to investigate the efficacy of a novel CyA oral formulation enabled by the integrated SmPill® oral drug delivery platform in a humanised mouse model of aGvHD. The study compared the approved optimised CyA (Neoral®) with SmPill®-enabled CyA and a systemic intravenous CyA formulation. Our findings clearly demonstrate superior efficacy of the novel SmPill® CyA in prolonging survival in a clinically relevant humanised aGvHD model. SmPill® CyA significantly reduced pathological score in the small intestine, colon, liver and lung of aGvHD mice. In addition, SmPill® CyA significantly reduced the levels of pro-inflammatory cytokines in all the GvHD target tissues examined. Notably, SmPill® CyA was significantly more potent in reducing GvHD associated pathology and inflammatory cytokine production compared to the optimised approved oral CyA formulation, Neoral®
ICD-11 PTSD and CPTSD: Implications for the rehabilitation of survivors of torture seeking international protection
No full textIntroduction: Rates of torture are especially
high among those seeking asylum, with
global estimates of forced migrants having
experienced torture exceeding 50%. Torture is the strongest predictor of PTSD amongst
refugee populations. This study assesses the
construct validity of the International Trauma
Questionnaire (ITQ), a self-report measure
of ICD-11 PTSD and Complex PTSD
(CPTSD) symptoms, within a population of
torture survivors seeking asylum in Ireland.
It further explores whether probable rates of
PTSD and CPTSD differ by sex and torture
or serious harm status.
Methods: A secondary data analysis of 264
treatment-seeking asylum seekers and refugees
who experienced torture or serious harm was
conducted.
Findings: A confirmatory factor analysis found that a six-factor correlated model
consisting of re-experiencing (Re), avoidance
(Av), threat (Th), affective dysregulation
(AD), negative self-concept (NSC), and disturbed relationships (DR) provided optimal fit
to the sample data. 32.4% of participants were
diagnosed with PTSD and a further 36.9%
met criteria for CPTSD. Experiencing torture
was significantly associated with higher odds
of meeting criteria for PTSD. No significant
differences between the sexes were found for
rates of PTSD or CPTSD. Discussion: Support for the construct validity of the ITQ was found among torture
survivors actively seeking international protection in Europe. Given the high rates of PTSD
and CPTSD found among torture survivors rehabilitation centres for survivors of torture
should consider CPTSD as part of their assessment and treatment programme
Interdisciplinary and Intersectoral Doctoral Education Design to Improve Graduate Employability
No full textTypically, less than half of doctoral graduates will be employed in academia immediately after
graduation, with less than 10%-15% achieving a long-term academic career. This leaves 85-90% of
PhD graduates seeking employment outside the academic setting, for example in industry and
government. The objective of the CHAMELEONS study (CHampioning A Multi-sectoral Education
and Learning Experience to Open New pathways for doctoral Students) is to develop innovative
educational interventions that shape more adaptable, entrepreneurial, and employable graduates, ready
to meet the challenges of the future. Stakeholders from the connected health industry, clinical care,
charities, patients, patient representatives, government, recent doctoral graduates, and academics were
invited to participate in a “World Café” participatory method for collecting qualitative data. Owing to
the COVID-19 health situation this took place via Zoom. Analysis of the results revealed 4 key learning
objectives for doctoral graduates to: 1. Develop networking and communication skills. 2. Understand
user centred research design. 3. Market research capacity and research skills. 4. Build an understanding
of themselves and others. This led to the development of three bespoke doctoral modules: 1. Forging
relationships: Building and Sustaining your Doctoral Network; 2. Managing the Project: Keeping on
Track with an Eye to the future; Module 3: Starting your Career: Future Proofing your Career and
Getting a Job. These modules are available to doctoral students across five European Universities
Understanding Nativist Elements Relating to Immigration Policies and to the American Constitution’s Natural Born Citizen Clause (forth. circa Sept. 2021) (South Korea)
No full textAbstract included in text. Cite as: Seth Barrett Tillman, Understanding Nativist Elements Relating to Immigration Policies and to the American Constitution’s Natural Born Citizen Clause in 32(2) Study on the American Constitution (forth. circa Sept. 2021) (South Korea) (accepted with revisions)
Design and Analysis of the Optical Beam Combiner and Corrugated Feed Horns for the QUBIC Instrument
No full textThe next major step in Big Bang cosmology will be the detection of primordial B-modes in the polarisation pattern of the Cosmic Microwave Background (CMB). These primordial B-modes are extremely faint and unprecedented levels of sensitivity will be required to detect them. The QUBIC (Q & U Bolometric Interferometer for Cosmology) instrument, first proposed in 2008 and now on the verge of being commissioned, aims to detect them by using the novel technique of bolometric interferometry to combine the control of systematics provided by an interferometer and the sensitivity provided by an imager. QUBIC is a ground-based instrument that will be installed in Salta Province, Argentina.
This thesis describes the detailed optical analysis of the QUBIC instrument and, in particular, its quasi-optical beam combiner. Two variations of QUBIC are analysed: the full instrument (FI) and a technological demonstrator (TD). It was decided to develop the smaller optical combiner of the TD in 2015. The justification for and analysis of the TD are also presented.
The QUBIC FI will observe over two bands: 150 GHz (with a 25% bandwidth) and 220 GHz (with an 18% bandwidth). The operation of the QUBIC optical combiner across these bands was investigated using the techniques of physical optics and electromagnetic mode-matching for the feedhorns. This modelling also provided an insight into multimoded operation of QUBIC in the higher band, which will be useful for future instruments that aim to exploit the phenomenon.
The optical modelling in this thesis has been used in the calibration and testing phases of the instrument and will be also useful in the future when observations begin in Argentina