3,296 research outputs found
Melanopsin-expressing intrinsically photosensitive retinal ganglion cells in retinal disease
Melanopsin containing intrinsically photosensitive Retinal Ganglion Cells (ipRGCs) are a class of photoreceptors with established roles in non-image forming processes. Their contributions to image forming vision may include the estimation of brightness. Animal models have been central for understanding the physiological mechanisms of ipRGC function and there is evidence of conservation of function across species. ipRGCs can be divided into 5 ganglion cell subtypes that show morphological and functional diversity. Research in humans has established that ipRGCs signal environmental irradiance to entrain the central body clock to the solar day for regulating circadian processes and sleep. In addition, ipRGCs mediate the pupil light reflex (PLR), making the PLR a readily accessible behavioural marker of ipRGC activity. Less is known about ipRGC function in retinal and optic nerve disease, with emerging research providing insight into their function in diabetes, retinitis pigmentosa, glaucoma and hereditary optic neuropathy. We briefly review the anatomical distributions, projections and basic physiological mechanisms of ipRGCs, their proposed and known functions in animals and humans with and without eye disease. We introduce a paradigm for differentiating inner and outer retinal inputs to the pupillary control pathway in retinal disease and apply this paradigm to patients with age-related macular degeneration (AMD). In these cases of patients with AMD, we provide the initial evidence that ipRGC function is altered, and that the dysfunction is more pronounced in advanced disease. Our perspective is that with refined pupillometry paradigms, the pupil light reflex can be extended to AMD assessment as a tool for the measurement of inner and outer retinal dysfunction
Die Bedeutung der Fascia stylopharyngea bei intraoralen Blockadetechniken
Zusammenfassung: Hintergrund: Mittels transoraler Blockade des Ganglion cervicale superius des Truncus sympathicus kann bei Trigeminusneuralgien durch Ausbreitung eines Opioids bis zum N.mandibularis eine zusätzliche Schmerzreduktion erzielt werden. Das Vorhandensein der Fascia stylopharyngea senkt möglicherweise die Erfolgsrate. Durch genaue anatomische Untersuchung der Faszie wollen wir auf die Effektivität der zusätzlichen Opioidwirkung rückschließen. Material und Methode: 103 Kopfhälften wurden untersucht, die Faszie von lateral her aufgesucht. Dabei unterschieden wir 3 Gruppen: GruppeA repräsentierte vollständig ausgebildete Faszienblätter, Gruppe Bunvollständige Faszien und in GruppeC war die Faszie nicht ausgebildet. Ergebnis: Die Faszie war in 86 vollständig und in 13 Fällen unvollständig ausgebildet. Lediglich in 4 Fällen fehlte sie vollends. Schlussfolgerung: Die Faszie kann die Erfolgsquote der Schmerzreduktion bei Trigeminusneuralgie beeinflusse
Abnormal domination of gilt sardine (Sardinella aurita) in the middle shelf ichthyoplankton community of Gulf of Cádiz (SW Iberian Peninsula) in summer: related changes in the hydrologic structure and implications in the larval fish and mesozooplankton assemblages finded.
During the yearly ‘Ictio.Alborán-Cádiz’ (1994–1997) multidisciplinary oceanographic surveys, the eggs and larvae of anchovy (Engraulis encrasicolus) are generally the dominant in the middle shelf ichthyoplankton community of the Gulf of Cádiz in summer. In the 1995 survey a notorius change have detected: the maximum localized abundance for ichthyoplanktonic components of gilt sardine (Sardinella aurita) have multiplied x 10 (eggs) and x 20 (larvae) the anchovy’s components. In this paper we discuss the observed changes in the hydrologic structure and in the larval fish and mesozooplankton assemblages (cluster analysis)
The electroretinogram:a useful tool for evaluating age-related macular disease?
With an ageing population, the number of age-related macular disease (ARMD) cases will inevitably rise. This gives greater impetus for the need to identify the disease earlier and assess treatments to slow disease progression. Differing electroretinogram (ERG) modalities have been reviewed in relation to the objective assessment of retinal function in ARMD and for monitoring the effectiveness of clinical interventions. Conflicting results have been found with regard to the efficacy of ERG findings in the investigation of ARMD in previous years. The newer multifocal ERG paradigm provides spatial topographical information about retinal function in ARMD. It has shown promising results in monitoring effectiveness of clinical interventions and studies are continuing in this area. Better knowledge of retinal function in ARMD may lead to enhanced treatments at each phase of the disease
Planar Superconducting Resonators with Internal Quality Factors above One Million
We describe the fabrication and measurement of microwave coplanar waveguide
resonators with internal quality factors above 10 million at high microwave
powers and over 1 million at low powers, with the best low power results
approaching 2 million, corresponding to ~1 photon in the resonator. These
quality factors are achieved by controllably producing very smooth and clean
interfaces between the resonators' aluminum metallization and the underlying
single crystal sapphire substrate. Additionally, we describe a method for
analyzing the resonator microwave response, with which we can directly
determine the internal quality factor and frequency of a resonator embedded in
an imperfect measurement circuit.Comment: 4 pages, 3 figures, 1 tabl
Melanopsin-Driven Pupil Response and Light Exposure in Non-seasonal Major Depressive Disorder
Background: Melanopsin-expressing intrinsically photosensitive Retinal Ganglion Cells (ipRGCs) signal non-imaging forming effects of environmental light for circadian phoentrainment, the pupil light reflex, and mood regulation. In seasonal affective disorder, ipRGC dysfunction is thought to cause abberant transmission of the external illumination for photoentrainment. It is not known if patients with non-seasonal depression have abnormal melanospin mediated signaling and/or irregular environmental light exposure.Methods: Twenty-one adults who live in a sub-tropical region, including eight patients with non-seasonal depression and thirteen age-matched healthy controls were recruited. The Mini International Neuropsychiatry Interview diagnosed the presence of a major depressive disorder. Light exposure was determined using actigraphy over a 2 week period. The melanopsin mediated post-illumination pupil response (PIPR) and outer retinal inputs to ipRGCs (transient pupil response and maximum pupil constriction amplitude) were measured in response to 1 s, short and long wavelength light with high and low melanopsin excitation.Results: The mean daylight exposure as a function of clock hours and total light exposure duration (mins) to illumination levels commonly recommended for depression therapy were not significantly different between groups. Out of 84 pupil measurements (42 each in the depression and control groups), the melanopsin-mediated PIPR amplitude, transient pupil response, and pupil constriction amplitude were not significantly different between groups.Conclusions: This report provides initial evidence of normal melanopsin function and environmental light exposures in patients with pre-dominately mid and moderate non-seasonal depression in a subtropical location in the southern hemisphere
Sleep habits around the world
The purpose of this study is to examine a relationship between sleep habits in college students at Clemson University and at The University of Vienna. Using the Pittsburgh Sleep Quality Index (PSQI), we define sleep habits as a) time they go to bed, b) time they wake up, and c) amount they slept at night. 324 Clemson participants and 292 Vienna participants from undergraduate psychology courses were asked to complete surveys regarding their sleep quality (PSQI). An independent sample t-test showed a significant difference in both the average times Clemson and Vienna students went to bed and woke up (p \u3c .001) as well as in the average total hours they slept at night (p \u3c .001). Our data findings suggest that Clemson students went to bed later, woke up earlier, and slept less on average than Vienna students
The effects of leaching from alkaline red mud on soil biota: modelling the conditions after the Hungarian red mud disaster
A soil column experiment was set up to investigate the effect of red mud from Ajka (Hungary) on a typical soil profile from the concerned area. The chemical changes caused by the leachate of the red mud and the effects of these changes on living organisms were assessed. Ecotoxicological tests with Vibrio fischeri, Sinapis alba and Folsomia candida were performed and the number of aerobic heterotrophic microorganisms was determined. The total, plant available, exchangeable and water soluble fractions of Na, Mo, Cu, and Cr increased in the soil mostly due to their leaching from the red mud layer and partly to the increase of the pH and DOC concentration. The chemical changes had significant effects on the test organisms only in the 0 – 30 cm soil layer except for F. candida that had a lower survival rate also in the 30 – 50 cm soil layer. There were no severe toxic effects detected on the test organisms. Furthermore in case of the aerobic heterotrophic cell number and S. alba germination a stimulating effect was revealed. However, the red mud itself was toxic, therefore the performed ecotoxicology tests have justified the removal of red mud from the soil surface after the disaster
Release Note -- Vbfnlo-2.6.0
Vbfnlo is a flexible parton level Monte Carlo program for the simulation of
vector boson fusion (VBF), double and triple vector boson (plus jet) production
in hadronic collisions at next-to-leading order (NLO) in the strong coupling
constant, as well as Higgs boson plus two jet production via gluon fusion at
the one-loop level. This note briefly describes the main additional features
and processes that have been added in the new release -- Vbfnlo Version 2.6.0.
At NLO QCD diboson production (W\gamma, WZ, ZZ, Z\gamma and \gamma\gamma),
same-sign W pair production via vector boson fusion and the process
W\gamma\gamma j have been implemented (for which one-loop tensor integrals up
to six-point functions are included). In addition, gluon induced diboson
production can be studied separately at the leading order (one-loop) level. The
diboson processes WW, WZ and W\gamma can be run with anomalous gauge boson
couplings, and anomalous couplings between a Higgs and a pair of gauge bosons
is included in WW, ZZ, Z\gamma and \gamma\gamma diboson production. The code
has also been extended to include anomalous gauge boson couplings for single
vector boson production via VBF, and a spin-2 model has been implemented for
diboson pair production via vector boson fusion.Comment: 14 pages, 6 tables; new code available at
http://www-itp.particle.uni-karlsruhe.de/vbfnlo
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