We present optical, X-ray and radio observations of the black hole transient (BHT) XTE J1752−223 towards and in quiescence. Optical photometry shows that the quiescent magnitude of XTE J1752−223 is ...fainter than 24.4 mag in the i′ band. A comparison with measurements of the source during its 2009-2010 outburst shows that the outburst amplitude is more than 8 mag in the i′ band. Known X-ray properties of the source combined with the faintness of the quiescence optical counterpart and the large outburst optical amplitude point towards a short orbital-period system (P
orb≲ 6.8 h) with an M type (or later) mass donor, at a distance of 3.5 ≲d≲ 8 kpc. Simultaneous X-ray and radio data were collected with Chandra and the Expanded Very Large Array (EVLA), allowing constraints to be placed on the quiescent X-ray and radio flux of XTE J1752−223. Furthermore, using data covering the final stage of the outburst decay, we investigated the low-luminosity end of the X-ray-radio correlation for this source and compared it with other BHTs. We found that XTE J1752−223 adds to the number of outliers with respect to the 'standard' X-ray-radio luminosity relation. Furthermore, XTE J1752−223 is the second source, after the BHT H1743−322, that shows a transition from the region of the outliers towards the 'standard' correlation at low luminosity. Finally, we report on a faint, variable X-ray source we discovered with Chandra at an angular distance of ∼2.9 arcsec to XTE J1752−223 and at a position angle consistent with that of the radio jets previously observed from the BHT. We discuss the possibility that we detected X-ray emission associated with a jet from XTE J1752−223.
We have carried out optical spectroscopy with the Anglo-Australian Telescope for 24 726 objects surrounding a sample of 19 giant radio galaxies (GRGs) selected to have redshifts in the range ...0.05–0.15 and projected linear sizes from 0.8 to 3.2 Mpc. Such radio galaxies are ideal candidates to study the warm-hot intergalactic medium because their radio lobes extend beyond the interstellar medium and haloes of their host galaxies, and into the tenuous intergalactic medium. We were able to measure redshifts for 9076 galaxies. Radio imaging of each GRG, including high-sensitivity, wide-band radio observations from the Australia Telescope Compact Array for 12 GRGs and host optical spectra (presented in a previous paper), is used in conjunction with the surrounding galaxy redshifts to trace large-scale structure. We find that the mean galaxy number overdensity in volumes of ∼700 Mpc3 near the GRG host galaxies is ∼70 indicating an overdense but non-virialized environment. A Fourier component analysis is used to quantify the anisotropy in the surrounding galaxy distribution. For GRGs with radio components offset from the radio axis, there is a clear influence of the environment with lobes appearing to be deflected away from overdensities in the surrounding medium. Furthermore, the GRG lobes tend to be normal to the plane defined by the galaxy neighbourhood close to the host. This indicates the tendency for lobes to grow to giant sizes in directions that avoid dense regions on both small and large scales.
We present the first analysis of global and hemispheric surface warming trends that attempts to quantify the major sources of uncertainty. We calculate global and hemispheric annual temperature ...anomalies by combining land surface air temperature and sea surface temperature (SST) through an optimal averaging technique. The technique allows estimation of uncertainties in the annual anomalies resulting from data gaps and random errors. We add independent uncertainties due to urbanisation, changing land‐based observing practices and SST bias corrections. We test the accuracy of the SST bias corrections, which represent the largest source of uncertainty in the data, through a suite of climate model simulations. These indicate that the corrections are likely to be fairly accurate on an annual average and on large space scales. Allowing for serial correlation and annual uncertainties, the best linear fit to annual global surface temperature gives an increase of 0.61±0.16°C between 1861 and 2000.
Diffusion tensor MRI (DT‐MRI) provides information about the structural organization and orientation of white matter fibres and, through the technique of ‘tractography’, reveals the trajectories of ...cerebral white matter tracts. We used tractography in the living human brain to address the disputed issue of the nature of occipital and temporal connections. Classical anatomical studies described direct fibre connections between occipital and anterior temporal cortex in a bundle labelled the inferior longitudinal fasciculus (ILF). However, their presence has been challenged by more recent evidence suggesting that connections between the two regions are entirely indirect, conveyed by the occipito‐temporal projection system—a chain of U‐shaped association fibres. DT‐MRI data were collected from 11 right‐handed healthy subjects (mean age 33.3 ± 4.7 years). Each data set was co‐registered with a standard MRI brain template, and a group‐averaged DT‐MRI data set was created. ‘Virtual’ in vivo dissection of occipito‐temporal connections was performed in the group‐averaged data. Further detailed virtual dissection was performed on the single brain data sets. Our results suggest that in addition to the indirect connections of the occipito‐temporal projection system: (i) a major associative connection between the occipital and anterior temporal lobe is provided by a fibre bundle whose origin, course and termination are consistent with classical descriptions of the ILF in man and with monkey visual anatomy; (ii) the tractography‐defined ILF is structurally distinct from fibres of the optic radiation and from U‐shaped fibres connecting adjacent gyri; (iii) it arises in extrastriate visual ‘association’ areas; and (iv) it projects to lateral and medial anterior temporal regions. While the function of the direct ILF pathway is unclear, it appears to mediate the fast transfer of visual signals to anterior temporal regions and neuromodulatory back‐projections from the amygdala to early visual areas. Future tractography studies of patients with occipito‐temporal disconnection syndromes may help define the functional roles of the direct and indirect occipito‐temporal pathways.
Background: Children who have been maltreated are at increased risk of further maltreatment. Competent identification of those at highest risk of further maltreatment is an important part of safe and ...effective practice, but is a complex and demanding task. Aim: To systematically review the research base predicting those children at highest risk of recurrent maltreatment. Methods: Systematic review of cohort studies investigating factors associated with substantiated maltreatment recurrence in children. Results: Sixteen studies met the inclusion criteria. The studies were heterogeneous. A variety of forms of maltreatment were considered. Four factors were most consistently identified as predicting future maltreatment: number of previous episodes of maltreatment; neglect (as opposed to other forms of maltreatment); parental conflict; and parental mental health problems. Children maltreated previously were approximately six times more likely to experience recurrent maltreatment than children who had not previously been maltreated. The risk of recurrence was highest in the period soon after the index episode of maltreatment (within 30 days), and diminished thereafter. Conclusions: There are factors clearly associated with an increased risk of recurrent maltreatment, and these should be considered in professional assessments of children who have been maltreated. A comprehensive approach to risk assessment, including but not solely based on these factors, is likely to lead to interventions which offer greater protection to children.
To examine the association between soluble tumor necrosis factor receptor 1 (sTNFR1) levels and kidney disease progression in Indigenous Australians at high risk of kidney disease.
This longitudinal ...observational study examined participants aged ≥18 years recruited from >20 sites across diabetes and/or kidney function strata. Baseline measures included sTNFR1, serum creatinine, urine albumin-to-creatinine ratio (uACR), HbA
, C-reactive protein (CRP), waist-to-hip ratio, systolic blood pressure, and medical history. Linear regression was used to estimate annual change in estimated glomerular filtration rate (eGFR) for increasing sTNFR1, and Cox proportional hazards were used to estimate the hazard ratio (HR) and 95% CI for developing a combined renal outcome (first of a ≥30% decline in eGFR with a follow-up eGFR <60 mL/min/1.73 m
, progression to renal replacement therapy, or renal death) for increasing sTNFR1.
Over a median of 3 years, participants with diabetes (
= 194) in the highest compared with the lowest quartile of sTNFR1 experienced significantly greater eGFR decline (-4.22 mL/min/1.73 m
/year 95% CI -7.06 to -1.38;
= 0.004), independent of baseline age, sex, eGFR, and uACR. The adjusted HR (95% CI) for participants with diabetes per doubling of sTNFR1 for the combined renal outcome (
= 32) was 3.8 (1.1-12.8;
= 0.03). No association between sTNFR1 and either renal outcome was observed for those without diabetes (
= 259).
sTNFR1 is associated with greater kidney disease progression independent of albuminuria and eGFR in Indigenous Australians with diabetes. Further research is required to assess whether TNFR1 operates independently of other metabolic factors associated with kidney disease progression.
We describe the spectroscopic target selection for the Galaxy And Mass Assembly (GAMA) survey. The input catalogue is drawn from the Sloan Digital Sky Survey (SDSS) and UKIRT Infrared Deep Sky Survey ...(UKIDSS). The initial aim is to measure redshifts for galaxies in three 4°× 12° regions at 9, 12 and 14.5 h, on the celestial equator, with magnitude selections r < 19.4, z < 18.2 and KAB < 17.6 over all three regions, and r < 19.8 in the 12-h region. The target density is 1080 deg−2 in the 12-h region and 720 deg−2 in the other regions. The average GAMA target density and area are compared with completed and ongoing galaxy redshift surveys. The GAMA survey implements a highly complete star–galaxy separation that jointly uses an intensity-profile separator (Δsg=rpsf−rmodel as per the SDSS) and a colour separator. The colour separator is defined as Δsg,jk=J−K−f(g−i), where f(g−i) is a quadratic fit to the J−K colour of the stellar locus over the range 0.3 < g−i < 2.3. All galaxy populations investigated are well separated with Δsg,jk > 0.2. From 2 yr out of a 3-yr AAOmega program on the Anglo-Australian Telescope, we have obtained 79 599 unique galaxy redshifts. Previously known redshifts in the GAMA region bring the total up to 98 497. The median galaxy redshift is 0.2 with 99 per cent at z < 0.5. We present some of the global statistical properties of the survey, including K-band galaxy counts, colour–redshift relations and preliminary n(z).
This study compared adaptations in fascicle lengths, pennation angles, and muscle thickness of the lateral and medial gastrocnemii in response to 6 weeks of stretch training. The nondominant plantar ...flexors of 11 males were stretched five times per week for 6 weeks and compared with the contralateral leg and a nonstretched control group of 10 males. During stretch training, instantaneous electromyography was utilized to ensure passive muscle stretch. At baseline, week three, week six and 1 week after the conclusion of stretch training, ultrasound was used to measure fascicle lengths, pennation angles, muscle thickness of the lateral gastrocnemius and medial gastrocnemius, and Achilles tendon thickness and length. Plantar flexion torque was measured, and voluntary activation was assessed. Muscle thickness increased 5.6% after 6 weeks of stretch training (P=.009). The fascicles in the lateral gastrocnemius lengthened to a greater extent than the medial. Overall, fascicles lengthened 25% (P<.001) in the muscle tendon junction and 5.1% (P<.001) in the muscle belly. Pennation angles were unchanged in the medial gastrocnemius but decreased in the lateral gastrocnemius 7.1% (P=.02). There was no change in maximal voluntary contraction, voluntary activation, tendon length, or thickness. This study demonstrates that stretch training is a viable modality to alter muscle architecture of the human gastrocnemius through lengthening of muscle fascicles, decreasing pennation angles, and increasing muscle thickness, albeit adaptations are unequal between the lateral and medial heads.
Understanding caregivers' experiences of care can identify barriers to timely and good quality care, and support the improvement of services. We aimed to explore caregivers' experiences and ...perceptions of pathways to care, from first access through various levels of health service, for seriously ill and injured children in Cape Town, South Africa, in order to identify areas for improvement.
Semi-structured, qualitative interviews were conducted with primary caregivers of children who were admitted to paediatric intensive care or died in the health system prior to intensive care admission. Interviews explored caregivers' experiences from when their child first became ill, through each level of health care to paediatric intensive care or death. A maximum variation sample of transcripts was purposively sampled from a larger cohort study based on demographic characteristics, child diagnosis, and outcome at 30 days; and analysed using the method of constant comparison.
Of the 282 caregivers who were interviewed in the larger cohort study, 45 interviews were included in this qualitative analysis. Some caregivers employed 'tactics' to gain quicker access to care, including bypassing lower levels of care, and negotiating or demanding to see a healthcare professional ahead of other patients. It was sometimes unclear how to access emergency care within facilities; and non-medical personnel informally judged illness severity and helped or hindered quicker access. Caregivers commonly misconceived ambulances to be slow to arrive, and were concerned when ambulance transfers were seemingly not prioritised by illness severity. Communication was often good, but some caregivers experienced language difficulties and/or criticism.
Interventions to improve child health care could be based on: reorganising the reception of seriously ill children and making the emergency route within healthcare facilities clear; promoting caregivers' use of ambulances and prioritising transfers according to illness severity; addressing language barriers, and emphasising the importance of effective communication to healthcare providers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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