627 research outputs found

    Poor sleep quality and progression of gait impairment in an incident Parkinson’s disease cohort

    Get PDF
    Abnormal sleep may associate with cognitive decline in Parkinson's disease (PD). Furthermore, sleep dysfunction may associate with worse motor outcome. We hypothesised that PD patients with poor quality sleep would have greater progression in gait dysfunction, due to structural and functional overlap in networks subserving sleep and gait regulation. 12 PD patients and 12 age-matched controls completed longitudinal follow-up over 36 months. Poor sleep efficiency and greater sleep fragmentation correlated significantly with progression of step-width variability, a gait characteristic mediated by postural control, providing evidence that poor sleep in PD is associated with a more rapid deterioration in gait

    Maternal Obesity and the Fetal Origins of the Metabolic Syndrome

    Get PDF
    Over recent decades there has been a rapid rise in metabolic disorders throughout the world. Whilst lifestyle and societal habits have contributed to the obesity epidemic, there is now increasing evidence that the early developmental environment of an infant can play a pivotal role in the ‘programming’ of an adverse physiological phenotype in later life. Clinical evidence highlights that maternal over-nutrition and/or obesity during pregnancy presents not only adverse effects on maternal health, but also persistent and deleterious effects in the developing child. Animal models are providing essential information into the underlying cellular and molecular mechanisms that contribute to this adverse phenotype. The use of this information will aid our understanding of the programming signals related to maternal and paternal over-nutrition and the improved healthcare for both mother and infant

    Host Galaxy Evolution in Radio-Loud AGN

    Full text link
    We investigate the luminosity evolution of the host galaxies of radio-loud AGN through Hubble Space Telescope imaging of 72 BL Lac objects, including new STIS imaging of nine z > 0.6 BL Lacs. With their intrinsically low accretion rates and their strongly beamed jets, BL Lacs provide a unique opportunity to probe host galaxy evolution independent of the biases and ambiguities implicit in quasar studies. We find that the host galaxies of BL Lacs evolve strongly, consistent with passive evolution from a period of active star formation in the range 0.5 <~ z <~ 2.5, and inconsistent with either passive evolution from a high formation redshift or a non-evolving population. This evolution is broadly consistent with that observed in the hosts of other radio-loud AGN, and inconsistent with the flatter luminosity evolution of quiescent early types and radio-quiet hosts. This indicates that active star formation, and hence galaxy interactions, are associated with the formation for radio-loud AGN, and that these host galaxies preferentially accrete less material after their formation epoch than galaxies without powerful radio jets. We discuss possible explanations for the link between merger history and the incidence of a radio jet.Comment: 37 pages, 8 figures, accepted for publication in ApJ, for full PDF incl. figures see http://www.ph.unimelb.edu.au/~modowd/papers/odowdurry2005.pd

    Delays in diagnosis of young women with symptomatic cervical cancer in England: an interview-based study

    Get PDF
    Background: Diagnosis may be delayed in young females with cervical cancer because of a failure to recognise symptoms. Aim: To examine the extent and determinants of delays in diagnosis of young females with symptomatic cervical cancer. Design and setting: A national descriptive study of time from symptoms to diagnosis of cervical cancer and risk factors for delay in diagnosis at all hospitals diagnosing cervical cancer in England. Method: One-hundred and twenty-eight patients <30 years with a recent diagnosis of cervical cancer were interviewed. Patient delay was defined as ?3 months from symptom onset to first presentation and provider delay as ? 3 months from first presentation to diagnosis. Results: Forty (31%) patients had presented symptomatically: 11 (28%) delayed presentation. Patient delay was more common in patients <25 than patients aged 25–29 (40% versus 15%, P = 0.16). Vaginal discharge was more common among patients who delayed presentation than those who did not; many reported not recognising this as a possible cancer symptom. Provider delay was reported by 24/40 (60%); in some no report was found in primary care records of a visual inspection of the cervix and some did not re-attend after the first presentation for several months. Gynaecological symptoms were common (84%) among patients who presented via screening. Conclusions: Young females with cervical cancer frequently delay presentation, and not recognising symptoms as serious may increase the risk of delay. Delay in diagnosis after first presentation is also common. There is some evidence that UK guidelines for managing young females with abnormal bleeding are not being followed

    Spatial tracking of individual fluid dispersed particles via Raman spectroscopy

    Get PDF
    This is the final version. Available on open access from Nature Research via the DOI in this recordWe demonstrate a method for the spatial tracking of individual particles, dispersed in a fluid host, via Raman spectroscopy. The effect of moving a particle upon the intensity of different bands within its Raman spectrum is first established computationally through a scattering matrix method. By comparing an experimental spectrum to the computational analysis, we show that the position of the particle can be obtained. We apply this method to the specific cases of molybdenum disulfide and graphene oxide particles, dispersed in a nematic liquid crystal, and contained within a microfluidic channel. By considering the ratio and difference between the intensities of the two Raman bands of molybdenum disulfide and graphene oxide, we demonstrate that an accurate position can be obtained in two dimensions.Engineering and Physical Sciences Research Council (EPSRC)Federal Target Program of the Ministry of Science and Higher Education of the Russian Federatio

    SSGSS: The Spitzer-SDSS-GALEX Spectroscopic Survey

    Get PDF
    The Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) provides a new sample of 101 star-forming galaxies at z < 0.2 with unprecedented multi-wavelength coverage. New mid- to far-infrared spectroscopy from the Spitzer Space Telescope is added to a rich suite of previous imaging and spectroscopy, including ROSAT, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, and Spitzer/SWIRE. Sample selection ensures an even coverage of the full range of normal galaxy properties, spanning two orders of magnitude in stellar mass, color, and dust attenuation. In this paper we present the SSGSS data set, describe the science drivers, and detail the sample selection, observations, data reduction, and quality assessment. Also in this paper, we compare the shape of the thermal continuum and the degree of silicate absorption of these typical, star-forming galaxies to those of starburst galaxies. We investigate the link between star formation rate, infrared luminosity, and total polycyclic aromatic hydrocarbon luminosity, with a view to calibrating the latter for spectral energy distribution models in photometric samples and at high redshift. Last, we take advantage of the 5-40 micron spectroscopic and far-infrared photometric coverage of this sample to perform detailed fitting of the Draine et al. dust models, and investigate the link between dust mass and star formation history and active galactic nucleus properties.Comment: 60 pages, 20 figure

    Mid-Infrared Spectral Measures of Star-Formation and AGN Activity in Normal Galaxies

    Get PDF
    We investigate the use of MIR PAH bands, continuum and emission lines as probes of star-formation and AGN activity in a sample of 100 'normal' and local (z~0.1) emission-line galaxies. The MIR spectra were obtained with the Spitzer Space Telescope Infrared Spectrograph (IRS) as part of the Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) which includes multi-wavelength photometry from the UV to the FIR and optical spectroscopy. The continuum and features were extracted using PAHFIT (Smith et al. 2007), a decomposition code which we find to yield PAH equivalent widths up to ~30 times larger than the commonly used spline methods. Despite the lack of extreme objects in our sample (such as strong AGNs, low metallicity galaxies or ULIRGs), we find significant variations in PAH, continuum and emission line properties and systematic trends between these MIR properties and optically derived physical properties such as age, metallicity and radiation field hardness. We revisit the diagnostic diagram relating PAH equivalent widths and [Ne II]12.8micrometers/[O IV]25.9micrometers line ratios and find it to be in much better agreement with the standard optical star-formation/AGN classification than when spline decompositions are used, while also potentially revealing obscured AGNs. The luminosity of individual PAH components, of the continuum, and with poorer statistics, of the neon emission lines and molecular hydrogen lines, are found to be tightly correlated to the total IR luminosity, making individual MIR components good gauges of the total dust emission in SF galaxies. Like the total IR luminosity, these individual components can be used to estimate dust attenuation in the UV and in Halpha lines based on energy balance arguments. We also propose average scaling relations between these components and dust corrected, Halpha derived star-formation rates.Comment: Accepted for publication in Ap

    A powerful intervention: general practitioners' use of sickness certification in depression

    Get PDF
    &lt;b&gt;Background&lt;/b&gt; Depression is frequently cited as the reason for sickness absence, and it is estimated that sickness certificates are issued in one third of consultations for depression. Previous research has considered GP views of sickness certification but not specifically in relation to depression. This study aimed to explore GPs views of sickness certification in relation to depression.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Methods&lt;/b&gt; A purposive sample of GP practices across Scotland was selected to reflect variations in levels of incapacity claimants and antidepressant prescribing. Qualitative interviews were carried out between 2008 and 2009.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Results&lt;/b&gt; A total of 30 GPs were interviewed. A number of common themes emerged including the perceived importance of GP advocacy on behalf of their patients, the tensions between stakeholders involved in the sickness certification system, the need to respond flexibly to patients who present with depression and the therapeutic nature of time away from work as well as the benefits of work. GPs reported that most patients with depression returned to work after a short period of absence and that it was often difficult to predict which patients would struggle to return to work.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions&lt;/b&gt; GPs reported that dealing with sickness certification and depression presents distinct challenges. Sickness certificates are often viewed as powerful interventions, the effectiveness of time away from work for those with depression should be subject to robust enquiry

    The HST Survey of BL Lacertae Objects. II. Host Galaxies

    Full text link
    We have used the HST WFPC2 camera to survey 132 BL Lac objects comprising seven complete radio-, X-ray-, and optically-selected samples. We obtained useful images for 110 targets spanning the redshift range 0 < z < 1.3. In two thirds of the BL Lac images, host galaxies are detected, including nearly all for z < 0.5 (58 of 63). The highest redshift host galaxy detected is in a BL Lac object at z=0.664. In 58 of the 72 resolved host galaxies, a de Vaucouleurs profile is significantly preferred, at >99% confidence, over a pure exponential disk; the two fits are comparable in the remaining 14 cases. These results limit the number of disk systems to at most 8% of BL Lacs (at 99% confidence), and are consistent with all BL~Lac host galaxies being ellipticals. The detected host galaxies are luminous ellipticals with a median absolute K-corrected magnitude of M_R= -23.7 +- 0.6 mag, at least one magnitude brighter than M* and comparable to brightest cluster galaxies. The galaxy morphologies are generally smooth and undisturbed, with small or negligible ellipticities (<0.2). There is no correlation between host galaxy and observed nuclear magnitude or estimated jet power corrected for beaming. If black hole mass is correlated linearly with bulge mass in general, this implies a large range in Eddington ratio. Present data strongly support the unification picture with FR I galaxies constituting the bulk of the parent population of BL Lac objects.Comment: Accepted for publication on ApJ. 38 pages, 8 figure
    • …
    corecore