86,888 research outputs found
Imposed positive defocus changes choroidal blood flow in young human subjects
Purpose: It has previously been found that imposing positive defocus changes axial length and choroidal thickness after only 30 min. In the present study, we investigated whether these changes may result from an altered choroidal blood flow. Methods: Eighteen young adult subjects watched a movie from a large screen (65 in.) in a dark room at 2 m distance. A 15-min wash-out period was followed by 30 min of watching the movie with a monocular positive defocus (+ 2.5D). Changes in axial length and ocular blood flow were measured before and after the defocus, by using low-coherent interferometer (LS 900, Haag-Streit, Switzerland) and a laser speckle flowgraphy (LSFG) RetFlow unit (Nidek Co., LTD, Japan), respectively. Three regions were analyzed: (1) the macular area, where choroidal blood flow can be measured, (2) the optic nerve head (ONH), and (3) retinal vessel segments. Results: Changes in choroidal blood flow were significantly and negatively correlated with changes in axial length that followed positive defocus in exposed eyes (R = − 0.67, p < 0.01). The absolute values of changes in choroidal blood flow in the defocused eyes were significantly larger than in the fellow control eyes (2.35 ± 2.16 AU vs. 1.37 ± 1.44 AU, respectively, p < 0.05). ONH and retinal blood flow were not associated with the induced changes in axial length. Conclusions: Positive defocus selectively alters choroidal, but not retinal or ONH blood flow in young human subjects after short-term visual exposure. The results suggest that blood flow modulation is involved in the mechanism of choroidal responses to optical defocus
Restless legs syndrome in diabetic neuropathy: a frequent manifestation of small fiber neuropathy
As the occurrence of restless legs syndrome (RLS) in diabetes is controversial, the aim of this study was to assess the prevalence of RLS in a cohort of patients with diabetic neuropathy and to analyze the features of the associated neuropathy. We investigated the occurrence of RLS diagnosed in accordance with the criteria of the International Restless Legs Syndrome Study Group in a cohort of patients with polyneuropathy and mononeuropathy multiplex associated with diabetes mellitus (DM), or impaired glucose tolerance (IGT), or impaired fasting glucose (IFG) in a retrospective study. RLS was present in 33/99 patients with neuropathy associated with DM/IGT/IFG (84 with distal polyneuropathy and 15 with multiple mononeuropathy). Comparing patients with or without RLS, small fiber sensory neuropathy was more common in the RLS patients (15/33 vs. 15/66), as were symptoms of burning feet (10/33 vs. 6/66). In several patients, RLS was responsive to neuropathic pain medications. The frequent occurrence of RLS in association with thermal dysesthesias may reflect the involvement of small sensory fibers in the form of hyperexcitable C fibers or A-delta fiber deafferentation. We suggest that RLS may be triggered by abnormal sensory inputs from small fibers, especially involved in neuropathy associated with DM/IGT/IFG. Our data show that RLS is a relevant feature of diabetic neuropathy, as a frequent and potentially treatable manifestation of small fiber involvement in the course of DM and IGT/IFG
Rifaximin versus neomycin on hyperammoniemia in chronic portal systemic encephalopathy of cirrhotics. A double-blind, randomized trial
Preliminary data suggest that rifaximin a new non-absorbable rifamycin-derivate, has beneficial effects on chronic portal systemic encephalopathy (PSE). To compare the efficacy and safety of rifaximin vs neomycin in the treatment of the hyperammoniemic state of PSE, 30 cirrhotic patients with grade I to III of PSE were randomly allocated to one of two groups: group A (15 patients) receiving rifaximin (400 mg/8h) and group B (15 patients) neomycin (1gr/8h). The duration of treatment was 21 consecutive days. Age, sex, hepatic and renal function, level of PSE, EEG and number connection test were similar in both groups. A significant decrease in blood ammonia levels was observed at the end of the treatment period in both groups; moreover rifaximin produced an earlier reduction of blood ammonia levels. The neuropsychic syndrome related to the PSE improved in both groups without significant difference. No side effects attributable to therapy were observed in the rifaximin group. These results indicate that, rifaximin is at least as effective as neomycin in the achievement and maintenance of low blood ammonia levels in cirrhotics with chronic PSE
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Galaxy formation in the Planck cosmology - II. Star-formation histories and post-processing magnitude reconstruction
RT acknowledges support from the Science and Technology Facilities Council via an Ernest Rutherford Fellowship (grant number ST/K004719/1).We adapt the L-GALAXIES semi-analytic model to follow the star formation histories (SFHs) of galaxies - by which we mean a record of the formation time and metallicities of the stars that are present in each galaxy at a given time. We use these to construct stellar spectra in post-processing, which offers large efficiency savings and allowsuser-defined spectral bands and dust models to be applied to data stored in the Millennium data repository. We contrast model SFHs from the Millennium Simulation with observed ones from the VESPA algorithm as applied to the Sloan Digital Sky Survey 7 (SDSS-7) catalogue. The overall agreement is good, with both simulated and SDSS galaxies showing a steeper SFH with increased stellar mass. The SFHs of blue and red galaxies, however, show poor agreement between data and simulations,which may indicate that the termination of star formation is too abrupt in the models. The mean star formation rate (SFR) of model galaxies is well defined and is accurately modelled by a double power law at all redshifts: SFR ∝ 1/(x-1.39 + x1.33), where x= (ta - t)/3.0 Gyr, t is the age of the stars and ta is the lookback time to the onset of galaxy formation;above a redshift of unity, this is well approximated by a gamma function: SFR ∝ x1.5e-x, where x =(ta - t)/2.0 Gyr. Individual galaxies, however, show a wide dispersion about this mean. When split by mass, the SFR peaks earlier for high-mass galaxies than for lower mass ones, and we interpret this downsizing as a mass-dependence in the evolution of the quenched fraction: the SFHs of star-forming galaxies show only a weak mass-dependence.Peer reviewe
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
Newspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
- …
