881 research outputs found

    Paediatric nasal foreign body in Calabar: A review of 5 -years experience

    Get PDF
    Background: Nasal foreign bodies are common domestic accidents in children. They can constitute a great challenge and management may require great skill. However, seldom does the Otolaryngologist keep track of the number and kinds of the foreign bodies he encounters. Objective: To evaluate cases of nasal foreign bodies among children managed in Otorhinolaryngology Department of the University of Calabar Teaching Hospital, Nigeria. Materials and Methods: A retrospective study of 215 Cases of paediatric nasal foreign bodies seen and managed in the Otorhinolaryngology Department of the University of Calabar Teaching Hospital from January 2015 to December 2018. Maximum age was 14years.The case notes of all children diagnosed with nasal foreign bodies within the period under review, from ENT Clinic, Ward and Children emergency Room were reviewed as related to age, gender, and type of foreign bodies, category of doctors, methods of removal and complications. Data were analysed and presented in descriptive, tabular and chart forms. Results: Of the 215 children, 43.7% were males and 56.3% females. The age range was 0 – 14 years, with a male: female ratio of 1:1.35.The peak age range at which nasal foreign bodies were found was 0 – 4 years (87%) and the least frequent age bracket was 10 – 14years (1.4%). Most of the children were asymptomatic (60%), and others had unilateral foul-smelling nasal discharge (40%). The most common foreign body were beads (34.9%), followed by seeds (23.2%). Most presentations were within one day (90%), followed by one week (7%). Most foreign bodies (59.5%) were inserted into the right nostril, and 40.5% into the left. No bilateral insertion was observed. Most of the foreign bodies (80%) were mechanically extracted with Jobson–Horne's probes without general anaesthesia. Mainly Registrars did most removals 65% while 25% were by Senior Registrars. Mild epistaxis was a complication in 5% of cases. Conclusion: Nasal foreign bodies are common in Calabar. The most frequently observed foreign bodies were beads and seeds. Therefore, public health education is needed for parents and caregivers. Keywords: Paediatrics, Nose, foreign bodies

    Automated Assessment of Image Quality in 2D Echocardiography Using Deep Learning

    Get PDF
    Echocardiography is the most used modality for assessing cardiac functions. The reliability of the echocardiographic measurements, however, depends on the quality of the images. Currently, the method of image quality assessment is a subjective process, where an echocardiography specialist visually inspects the images. An automated image quality assessment system is thus required. Here, we have reported on the feasibility of using deep learning for developing such automated quality scoring systems. A scoring system was proposed to include specific quality attributes for on-axis, contrast/gain and left ventricular (LV) foreshortening of the apical view. We prepared and used 1,039 echocardiographic patient datasets for model development and testing. Average accuracy of at least 86% was obtained with computation speed at 0.013ms per frame which indicated the feasibility for real-time deployment

    Knudsen gas in a finite random tube: transport diffusion and first passage properties

    Full text link
    We consider transport diffusion in a stochastic billiard in a random tube which is elongated in the direction of the first coordinate (the tube axis). Inside the random tube, which is stationary and ergodic, non-interacting particles move straight with constant speed. Upon hitting the tube walls, they are reflected randomly, according to the cosine law: the density of the outgoing direction is proportional to the cosine of the angle between this direction and the normal vector. Steady state transport is studied by introducing an open tube segment as follows: We cut out a large finite segment of the tube with segment boundaries perpendicular to the tube axis. Particles which leave this piece through the segment boundaries disappear from the system. Through stationary injection of particles at one boundary of the segment a steady state with non-vanishing stationary particle current is maintained. We prove (i) that in the thermodynamic limit of an infinite open piece the coarse-grained density profile inside the segment is linear, and (ii) that the transport diffusion coefficient obtained from the ratio of stationary current and effective boundary density gradient equals the diffusion coefficient of a tagged particle in an infinite tube. Thus we prove Fick's law and equality of transport diffusion and self-diffusion coefficients for quite generic rough (random) tubes. We also study some properties of the crossing time and compute the Milne extrapolation length in dependence on the shape of the random tube.Comment: 51 pages, 3 figure

    Constraints on early dark energy from CMB lensing and weak lensing tomography

    Get PDF
    Dark energy can be studied by its influence on the expansion of the Universe as well as on the growth history of the large-scale structure. In this paper, we follow the growth of the cosmic density field in early dark energy cosmologies by combining observations of the primary CMB temperature and polarisation power spectra at high redshift, of the CMB lensing deflection field at intermediate redshift and of weak cosmic shear at low redshifts for constraining the allowed amount of early dark energy. We present these forecasts using the Fisher-matrix formalism and consider the combination of Planck-data with the weak lensing survey of Euclid. We find that combining these data sets gives powerful constraints on early dark energy and is able to break degeneracies in the parameter set inherent to the various observational channels. The derived statistical 1-sigma-bound on the early dark energy density parameter is sigma(Omega_d^e)=0.0022 which suggests that early dark energy models can be well examined in our approach. In addition, we derive the dark energy figure of merit for the considered dark energy parameterisation and comment on the applicability of the growth index to early dark energy cosmologies.Comment: 25 pages, 14 figures, 3 tables; v2: very minor additions, updated to match version to be published in JCA

    The Importance of Time Congruity in the Organisation.

    Get PDF
    In 1991 Kaufman, Lane, and Lindquist proposed that time congruity in terms of an individual's time preferences and the time use methods of an organisation would lead to satisfactory performance and enhancement of quality of work and general life. The research reported here presents a study which uses commensurate person and job measures of time personality in an organisational setting to assess the effects of time congruity on one aspect of work life, job-related affective well-being. Results show that time personality and time congruity were found to have direct effects on well-being and the influence of time congruity was found to be mediated through time personality, thus contributing to the person–job (P–J) fit literature which suggests that direct effects are often more important than indirect effects. The study also provides some practical examples of ways to address some of the previously cited methodological issues in P–J fit research

    Effects of a nanoscopic filler on the structure and dynamics of a simulated polymer melt and the relationship to ultra-thin films

    Get PDF
    We perform molecular dynamics simulations of an idealized polymer melt surrounding a nanoscopic filler particle to probe the effects of a filler on the local melt structure and dynamics. We show that the glass transition temperature TgT_g of the melt can be shifted to either higher or lower temperatures by appropriately tuning the interactions between polymer and filler. A gradual change of the polymer dynamics approaching the filler surface causes the change in the glass transition. We also find that while the bulk structure of the polymers changes little, the polymers close to the surface tend to be elongated and flattened, independent of the type of interaction we study. Consequently, the dynamics appear strongly influenced by the interactions, while the melt structure is only altered by the geometric constraints imposed by the presence of the filler. Our findings show a strong similarity to those obtained for ultra-thin polymer films (thickness â‰Č100\lesssim 100 nm) suggesting that both ultra-thin films and filled-polymer systems might be understood in the same context

    Failing boys and moral panics: perspectives on the underachievement debate

    Get PDF
    The paper re-examines the underachievement debate from the perspective of the ‘discourse of derision’ that surrounds much writing in this area. It considers the contradictions and inconsistencies which underpin much of the discourse – from a reinterpretation of examination scores, to the conflation of the concepts of ‘under’ and ‘low’ achievement and finally to the lack of consensus on a means of defining and measuring the term underachievement. In doing so, this paper suggests a more innovative approach for understanding, re-evaluating and perhaps rejecting the notion of underachievement

    Properties of Ly-alpha and Gamma Ray Burst selected starbursts at high redshifts

    Full text link
    Selection of starbursts through either deep narrow band imaging of redshifted Ly-alpha emitters, or localisation of host galaxies of gamma-ray bursts both give access to starburst galaxies that are significantly fainter than what is currently available from selection techniques based on the continuum (such as Lyman-break selection). We here present results from a survey for Ly-alpha emitters at z=3, conducted at the European Southern Observatory's Very Large Telescope. Furthermore, we briefly describe the properties of host galaxies of gamma-ray bursts at z>2. The majority of both Ly-alpha and gamma-ray burst selected starbursts are fainter than the flux limit of the Lyman-break galaxy sample, suggesting that a significant fraction of the integrated star formation at z~3 is located in galaxies at the faint end of the luminosity function.Comment: invited talk, 6 pages, 3 figures, to appear in ``Starbursts from 30 Doradus to Lyman Break Galaxies'', eds. R. de Grijs, R. M. Gonzalez Delgado, Astrophysics & Space Science Library Series, Kluwer (in press

    Sociodemographic Drivers of Donor and Recipient Gender Disparities in Living Kidney Donation in Australia

    Get PDF
    Published online 26 May 2023Background: Females account for 60% of all living kidney donors worldwide. We defined the proportion of female to male donors for living donor kidney transplantation stratified by recipient gender, and explored the factors associated with female kidney donation. Methods: Data from the ANZDATA (Australian and New Zealand Dialysis and Transplantation) and ANZOD (Australian and New Zealand Organ Donor) registries (2002–2019) were used to identify the sociodemographic characteristics and their interactions associated with living donation from female donors. We derived the predicted probabilities from adjusted logistic models using marginal means. Results: Of 3523 living donor pairs, 2203 (63%) recipients were male, and 2012 (57%) donors were female. Male recipients were more likely to receive kidneys from female donors than male donors. Donor and recipient sex association was modified by donor-recipient relationship (P < 0.01), with sensitivity analysis suggesting that spousal donor-recipient pairs drive this interaction. Older recipients residing in regional or remote areas were more likely to receive kidneys from female donors compared with those from major cities (aged $60 years: 0.67 [0.63–0.71] vs. aged <60 years: 0.57 [0.53–0.60]). Conclusions: Factors associated with female donation include recipient sex, with spousal donors contributing to the interaction between recipient gender and donor-recipient relationship. Recipient age and location of residence have interactive effects on the likelihood of living donor transplantation from female donors.Siah Kim, Anita van Zwieten, Melanie Wyld, Maleeka Ladhani, Chandana Guha, Amanda Dominello, Kylie-Ann Mallitt, Anna Francis, Roslyn B. Mannon and Germaine Won

    Post-stimulus fMRI and EEG responses: evidence for a neuronal origin hypothesised to be inhibitory

    Get PDF
    Post-stimulus undershoots, negative responses following cessation of stimulation, are widely observed in functional magnetic resonance (fMRI) blood oxygenation level dependent (BOLD) data. However, the debate surrounding whether the origin of this response phase is neuronal or vascular, and whether it provides functionally relevant information, that is additional to what is contained in primary response, means that undershoots are widely overlooked. We simultaneously recorded electroencephalography (EEG), BOLD and cerebral blood-flow (CBF) [obtained from arterial spin labelled (ASL) fMRI] fMRI responses to hemifield checkerboard stimulation to test the potential neural origin of the fMRI post-stimulus undershoot. The post-stimulus BOLD and CBF signal amplitudes in both contralateral and ipsilateral visual cortex depended on the post-stimulus power of the 8-13 Hz (alpha) EEG neuronal activity, such that trials with highest EEG power showed largest fMRI undershoots in contralateral visual cortex. This correlation in post-stimulus EEG-fMRI responses was not predicted by the primary response amplitude. In the contralateral visual cortex we observed a decrease in both cerebral rate of oxygen metabolism (CMRO2) and CBF during the post-stimulus phase. In addition, the coupling ratio (n) between CMRO2 and CBF was significantly lower during the positive contralateral primary response phase compared with the post-stimulus phase and we propose that this reflects an altered balance of excitatory and inhibitory neuronal activity. Together our data provide strong evidence that the post-stimulus phase of the BOLD response has a neural origin which reflects, at least partially, an uncoupling of the neuronal responses driving the primary and post-stimulus responses, explaining the uncoupling of the signals measured in the two response phases. We suggest our results are consistent with inhibitory processes driving the post-stimulus EEG and fMRI responses. We therefore propose that new methods are required to model the post-stimulus and primary responses independently, enabling separate investigation of response phases in cognitive function and neurological disease
    • 

    corecore