11,079 research outputs found
Clinical and cost-effectiveness of internal limiting membrane peeling for patients with idiopathic full thickness macular hole. Protocol for a Randomised Controlled Trial : FILMS (Full-thickness macular hole and Internal Limiting Membrane peeling Study)
Background: A full-thickness macular hole (FTMH) is a common retinal condition associated with impaired vision. Randomised controlled trials (RCTs) have demonstrated that surgery, by means of pars plana vitrectomy and post-operative intraocular tamponade with gas, is effective for stage 2, 3 and 4 FTMH. Internal limiting membrane (ILM) peeling has been introduced as an additional surgical manoeuvre to increase the success of the surgery; i.e. increase rates of hole closure and visual improvement. However, little robust evidence exists supporting the superiority of ILM peeling compared with no-peeling techniques. The purpose of FILMS (Fullthickness macular hole and Internal Limiting Membrane peeling Study) is to determine whether ILM peeling improves the visual function, the anatomical closure of FTMH, and the quality of life of patients affected by this disorder, and the cost-effectiveness of the surgery.
Methods/Design: Patients with stage 2–3 idiopathic FTMH of less or equal than 18 months duration (based on symptoms reported by the participant) and with a visual acuity ≤ 20/40 in the study eye will be enrolled in this FILMS from eight sites across the UK and Ireland. Participants will be randomised to receive combined cataract surgery (phacoemulsification and intraocular lens implantation) and pars plana vitrectomy with postoperative intraocular tamponade with gas, with or without ILM peeling. The primary outcome is distance visual acuity at 6 months. Secondary outcomes include distance visual acuity at 3 and 24 months, near visual acuity at 3, 6, and 24 months, contrast sensitivity at 6 months, reading speed at 6 months, anatomical closure of the macular hole at each time point (1, 3, 6, and 24 months), health related quality of life (HRQOL) at six months, costs to the health service and the participant, incremental costs per quality adjusted life year (QALY) and adverse events.
Discussion: FILMS will provide high quality evidence on the role of ILM peeling in FTMH surgery.
Trial registration: This trial is registered with Current Controlled Trials ISRCTN number 33175422 and Clinical Trials.gov identifier NCT00286507.Chief Scientist Office, Scotland (project ref no CZH/4/235), NHS GrampianPeer reviewedPublisher PD
2019 Workforce Assessment of Michigans Local and Regional Food System
This report is the first in a series summarizing a 2019 workforce assessment of Michigan's local and regional food system. The local and regional food system can be defined in a number of ways. For the purposes of this study, the local and regional food systems encompass organizations that produce, process, or distribute food from Michigan that is available to Michigan consumers, and/or organizations that support this system.The research included: a scan of Michigan's food system jobs: where we collected and analyzed secondary labormarket data to identify local and regional food systems employment; demand; projected growth; median wages; and worker demographics, an employer's perspective of Michigan's local and regional food system workforce, and a scan of education and training opportunities in Michigan's local and regional food system: an inventory of education and training programs for local and regional food system jobs
Positional dependence of transcriptional inhibition by DNA torsional stress in yeast chromosomes
How DNA helical tension is constrained along the linear chromosomes of eukaryotic cells is poorly understood. In this study, we induced the accumulation of DNA (+) helical tension in Saccharomyces cerevisiae cells and examined how DNA transcription was affected along yeast chromosomes. The results revealed that, whereas the overwinding of DNA produced a general impairment of transcription initiation, genes situated at <100 kb from the chromosomal ends gradually escaped from the transcription stall. This novel positional effect seemed to be a simple function of the gene distance to the telomere: It occurred evenly in all 32 chromosome extremities and was independent of the atypical structure and transcription activity of subtelomeric chromatin. These results suggest that DNA helical tension dissipates at chromosomal ends and, therefore, provides a functional indication that yeast chromosome extremities are topologically open. The gradual escape from the transcription stall along the chromosomal flanks also indicates that friction restrictions to DNA twist diffusion, rather than tight topological boundaries, might suffice to confine DNA helical tension along eukaryotic chromatin
Ring Formation from an Oscillating Black Hole
Massive black hole (BH) mergers can result in the merger remnant receiving a
"kick", of order 200 km s or more, which will cause the remnant to
oscillate about the galaxy centre. Here we analyze the case where the BH
oscillates through the galaxy centre perpendicular or parallel to the plane of
the galaxy for a model galaxy consisting of an exponential disk, a Plummer
model bulge, and an isothermal dark matter halo. For the perpendicular motion
we find that there is a strong resonant forcing of the disk radial motion near
but somewhat less than the "resonant radii" where the BH oscillation
frequency is equal one-half, one-fourth, (1/6, etc.) of the radial epicyclic
frequency in the plane of the disk. Near the resonant radii there can be a
strong enhancement of the radial flow and disk density which can lead to shock
formation. In turn the shock may trigger the formation of a ring of stars near
. As an example, for a BH mass of and a kick velocity of
150 km s, we find that the resonant radii lie between 0.2 and 1 kpc. For
BH motion parallel to the plane of the galaxy we find that the BH leaves behind
it a supersonic wake where star formation may be triggered. The shape of the
wake is calculated as well as the slow-down time of the BH.
The differential rotation of the disk stretches the wake into ring-like
segments.Comment: 7 pages, 7 figure
Anion height as a controlling parameter for the superconductivity in iron pnictides and cuprates
Both families of high superconductors, iron pnictides and cuprates,
exhibit material dependence of superconductivity. Here, we study its origin
within the spin fluctuation pairing theory based on multiorbital models that
take into account realistic band structures. For pnictides, we show that the
presence and absence of Fermi surface pockets is sensitive to the pnictogen
height measured from the iron plane due to the multiorbital nature of the
system, which is reflected to the nodeless/nodal form of the superconducting
gap and . Surprisingly, even for the cuprates, which is conventionally
modeled by a single orbital model, the multiorbital band structure is shown to
play a crucial role in the material dependence of superconductivity. In fact,
by adopting a two orbital model that considers the orbital on top of
the orbital, we can resolve a long standing puzzle of why the
single layered Hg cuprate have much higher than the La cuprate.
Interestingly, here again the apical oxygen height measured from the CuO
plane plays an important role in determining the relative energy difference
between and orbitals, thereby strongly affecting the
superconductivity.Comment: 8 pages, 7 figures, submitted as Proceedings of SNS201
Scintigraphic assessment of bone status at one year following hip resurfacing : comparison of two surgical approaches using SPECT-CT scan
Objectives: To study the vascularity and bone metabolism of the femoral head/neck following hip resurfacing arthroplasty, and to use these results to compare the posterior and the trochanteric-flip approaches.
Methods: In our previous work, we reported changes to intra-operative blood flow during hip resurfacing arthroplasty comparing two surgical approaches. In this study, we report the vascularity and the metabolic bone function in the proximal femur in these same patients at one year after the surgery. Vascularity and bone function was assessed using scintigraphic techniques. Of the 13 patients who agreed to take part, eight had their arthroplasty through a posterior approach and five through a trochanteric-flip approach.
Results: One year after surgery, we found no difference in the vascularity (vascular phase) and metabolic bone function (delayed phase) at the junction of the femoral head/neck between the two groups of patients. Higher radiopharmaceutical uptake was found in the region of the greater trochanter in the trochanteric-flip group, related to the healing osteotomy.
Conclusions: Our findings using scintigraphic techniques suggest that the greater intra-operative reduction in blood flow to the junction of the femoral head/neck, which is seen with the posterior approach compared with trochanteric flip, does not result in any difference in vascularity or metabolic bone function one year after surgery
WIP deficiency reveals a differential role for WIP and the actin cytoskeleton in T and B cell activation
Producción CientíficaWIP stabilizes actin filaments and is important for filopodium formation. To define the role of WIP in immunity, we generated WIP-deficient mice. WIP(minus sign/minus sign) mice have normal lymphocyte development, but their T cells fail to proliferate, secrete IL-2, increase their F-actin content, polarize and extend protrusions following T cell receptor ligation, and are deficient in conjugate formation with superantigen-presenting B cells and anti-CD3 bilayers. In contrast, WIP-deficient B lymphocytes have enhanced proliferation and CD69 expression following B cell receptor ligation and mount normal antibody responses to T-independent antigens. Both WIP-deficient T and B cells show a profound defect in their subcortical actin filament networks. These results suggest that WIP is important for immunologic synapse formation and T cell activation
Spectroscopic bulge-disc decomposition: a new method to study the evolution of lenticular galaxies
A new method for spectroscopic bulge-disc decomposition is presented, in
which the spatial light profile in a two-dimensional spectrum is decomposed
wavelength-by-wavelength into bulge and disc components, allowing separate
one-dimensional spectra for each component to be constructed. This method has
been applied to observations of a sample of nine S0s in the Fornax Cluster in
order to obtain clean high-quality spectra of their individual bulge and disc
components. So far this decomposition has only been fully successful when
applied to galaxies with clean light profiles, consequently limiting the number
of galaxies that could be separated into bulge and disc components. Lick index
stellar population analysis of the component spectra reveals that in those
galaxies where the bulge and disc could be distinguished, the bulges have
systematically higher metallicities and younger stellar populations than the
discs. This correlation is consistent with a picture in which S0 formation
comprises the shutting down of star formation in the disc accompanied by a
final burst of star formation in the bulge. The variation in spatial-fit
parameters with wavelength also allows us to measure approximate colour
gradients in the individual components. Such gradients were detected separately
in both bulges and discs, in the sense that redder light is systematically more
centrally concentrated in all components. However, a search for radial
variations in the absorption line strengths determined for the individual
components revealed that they are absent from the vast majority of S0 discs and
bulges. The absence of gradients in line indices for most galaxies implies that
the colour gradient cannot be attributed to age or metallicity variations, and
is therefore most likely associated with varying degrees of obscuration by
dust.Comment: 10 pages, 10 figures, 1 table, accepted for publication in MNRA
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