945 resultados para Diamond eyes


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Mycoplasma conjunctivae is considered the major cause of infectious keratoconjunctivitis (IKC) in Alpine ibex (Capra i. ibex) and chamois (Rupicapra r. rupicapra). While it is known that domestic sheep can act as healthy carriers for M. conjunctivae, this question has not been addressed in wild ungulates so far. In this study, bacteriological investigations and field observations were performed to assess whether free-ranging Alpine ibex can be healthy carriers of M. conjunctivae. Among 136 ibex without clinical signs of IKC, M. conjunctivae was identified 26 times (19.1%) by TaqMan PCR. To assess the potential pathogenicity of M. conjunctivae strains isolated from asymptomatic eyes, strains from three healthy ibex and from 15 IKC-ibex and IKC-chamois were analysed genetically by DNA sequence analysis of the variable part of the lppS gene. No significant differences were observed between strains from asymptomatic and clinically affected animals, reflecting the assumption that healthy ibex may act as carriers for M. conjunctivae strains that may be pathogenic for other individuals. Our results further indicate that development of IKC is associated with M. conjunctivae load in the eyes. In addition, a questionnaire survey revealed that IKC is generally less common in ibex than chamois and that infection in wild ungulates is not necessarily linked to the presence of sheep. These data support the hypothesis that apparently healthy ibex may be important in the epizootiology of IKC and indicate that host predilection may play a role in IKC development.

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To date, only little is known about the self-directed perception and processing of subtle gaze cues in social anxiety that might however contribute to excessive feelings of being looked at by others. Using a web-based approach, participants (n=174) were asked whether or not briefly (300 ms) presented facial expressions modulated in gaze direction (0°, 2°, 4°, 6°, 8°) and valence (angry, fearful, happy, neutral) were directed at them. The results demonstrate a positive, linear relationship between self-reported social anxiety and stronger self-directed perception of others' gaze directions, particularly for negative (angry, fearful) and neutral expressions. Furthermore, faster responding was found for gaze more clearly directed at socially anxious individuals (0°, 2°, and 4°) suggesting a tendency to avoid direct gaze. In sum, the results illustrate an altered self-directed perception of subtle gaze cues. The possibly amplifying effects of social stress on biased self-directed perception of eye gaze are discussed.

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AIMS To assess the functional and morphological outcome of eyes with neovascular AMD treated with intravitreal ranbizumab following an exit strategy treatment regime. METHODS The Bern treatment regime for neovascular AMD has a fixed injection schedule, even in the non-active stage of the disease. The regimen has been adapted from the PIER study treatment protocol. Eyes with non-active AMD will receive 4 injections in the first year, and 2 injections in the second year of follow-up before treatment stops. Patients that received ranibizumab for treatment and reached the exit criteria were identified, and charts were reviewed to assess functional and morphological outcome. RESULTS Only 2.6% of all patients (15 out of 575 patients) reached the exit criteria. Mean change in best corrected ETDRS visual acuity (VA) was 4.5±16.9 letters when comparing baseline VA to 4 weeks after the last injection (p=0.32). OCT mean foveal thickness was significantly thinner after last treatment (247.9±43.0 µm) compared to baseline (332.5±83.1 µm, p=0.002). The mean total number of ranibizumab injections was 15.6±8.0, and the mean total treatment period was 40.9±18.3 months. Twenty percent of eyes had geographic atrophy present at baseline versus 46.6% at the end of treatment. CONCLUSIONS Even with a fixed treatment regime and a defined treatment exit strategy, only a small percentage of patients reach exit criteria. Retinal thickness has been significantly reduced by repeated intravitreal ranibizumab injections, and geographic atrophy became more frequent.

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This study investigated the roles of the right and left dorsolateral prefrontal (rDLPFC, lDLPFC) and the medial frontal cortex (MFC) in executive functioning using a theta burst transcranial magnetic stimulation (TMS) approach. Healthy subjects solved two visual search tasks: a number search task with low cognitive demands, and a number and letter search task with high cognitive demands. To observe how subjects solved the tasks, we assessed their behavior with and without TMS using eye movements when subjects were confronted with specific executive demands. To observe executive functions, we were particularly interested in TMS-induced changes in visual exploration strategies found to be associated with good or bad performance in a control condition without TMS stimulation. TMS left processing time unchanged in both tasks. Inhibition of the rDLPFC resulted in a decrease in anticipatory fixations in the number search task, i.e., a decrease in a good strategy in this low demand task. This was paired with a decrease in stimulus fixations. Together, these results point to a role of the rDLPFC in planning and response selection. Inhibition of the lDLPFC and the MFC resulted in an increase in anticipatory fixations in the number and letter search task, i.e., an increase in the application of a good strategy in this task. We interpret these results as a compensatory strategy to account for TMS-induced deficits in attentional switching when faced with high switching demands. After inhibition of the lDLPFC, an increase in regressive fixations was found in the number and letter search task. In the context of high working memory demands, this strategy appears to support TMS-induced working memory deficits. Combining an experimental TMS approach with the recording of eye movements proved sensitive to discrete decrements of executive functions and allows pinpointing the functional organization of the frontal lobes.

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Two polycrystalline diamond surfaces, manufactured by chemical vapour deposition (CVD) technique, are investigated regarding their applicability as charge state conversion surfaces (CS) for use in a low energy neutral atom imaging instrument in space research. The capability of the surfaces for converting neutral atoms into negative ions via surface ionisation processes was measured for hydrogen and oxygen with particle energies in the range from 100 eV to 1 keV and for angles of incidence between 6 deg and 15 deg. We observed surface charging during the surface ionisation processes for one of the CVD samples due to low electrical conductivity of the material. Measurements on the other CVD diamond sample resulted in ionisation efficiencies of ~2 % for H and up to 12 % for O. Analysis of the angular scattering revealed very narrow and almost circular scattering distributions. Comparison of the results with the data of the CS of the IBEX-Lo sensor shows that CVD diamond has great potential as CS material for future space missions.

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Recent studies provide promising methodological advances in the use of pupillometry as on-line measurement of cognitive processes and show that visual attention allocation, mind-wandering, mental imagery, and even rhyme expectations can influence the size of the human pupil.

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Zu Beginn des 17. Jahrhunderts hatte sich die Malerei in Antwerpen vor allem durch Rubens als Medium einer zunehmend global verbundenen Welt etabliert. Doch auch zahlreiche von Van Dycks Porträts sind Zeugnisse eines oft hochgradig ambivalenten Kosmopolitismus. Neben Gemälden von international agierenden Antwerpener Händlern und Gelehrten fertigte der Künstler auch in Genua und England Porträts der adligen Elite an, in welchen sich deren globale Erfahrungen und Ambitionen spiegelten. Van Dyck reagierte in der Inszenierung der Marchesa Elena Grimaldi Cattaneo, mit einem schwarzen Sklaven, wie in der des Earl of Denbigh, zwischen einheimischen und exotischen Elementen, auf spezifische Anforderungen an das repräsentative Porträt im Zeitalter des disenclavement. Diese Anforderungen werden besonders deutlich in dem für eine geplante Expedition nach Madagaskar entstandenen Porträt des Earls of Arundel und dessen Frau Alethea Talbot. Das Gemälde verbindet Elemente herrschaftlicher, merkantilistischer und intellektueller Selbststilisierung mit einer Reduktion auf wenige, innovative Elemente. Die majestätische Inszenierung des Paars ist nur in einem globalen Kontext zu erklären, so dass sich die Frage nach der Funktion des in mehreren Werkstattkopien erhaltenen Gemäldes stellt. Hatte Van Dyck in seiner Komposition eine Lösung gefunden, die im Kontext des englischen Hofes, möglicherweise als Teil eines Festes, wie auch für potentielle Investoren, sowie die verarmte Landbevölkerung, die in der Indentur ihre einzige Hoffnung sah, gleichermaßen überzeugend wirkte? Die Hybris in dem überlebensgroßen Porträts des Paares, das mit leuchtend heller Haut, in kostbar glänzende Stoffe gekleidet und mit modernen Messinstrumenten in den Händen dargestellt ist, lässt es als ideales Medium der globalen Ambitionen des Paars erscheinen.

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Weniger unsachgemässe Abfallentsorgung dank Watching Eyes – dies war die These unseres Feldexperiments. In fünf Gemeinden der Region Bern und Olten wurde während drei Monaten die Wirkung von aufklebbaren Augenpaaren (sog. „Watching Eyes“) auf die unsachgemässe Abfallentsorgung bei Recyclingsammelstellen getestet. Die Menge des Abfalls konnte durch Watching Eyes um bis zu 35 % reduziert werden. Ebenfalls bestätigt wurden die zusätzlichen Erwartungen, dass an Unterflur - Containertypen und an offen einsehbaren Sammelstellen weniger Müll unsachgemäss abgestellt wird. Alle Erkenntnisse passen in die Theorie, dass Benutzer der Sammelstellen sich eher normkonform verhalten, wenn sie sich beobachtet fühlen. Ausserdem macht diese Forschungsarbeit Hoffnung, dass Watching Eyes für ein gesellschaftsrelevantes Problem, die unsachgerechte Abfallentsorgung, Hilfestellung bieten können. Watching Eyes - Aufkleber entfalten ihren grössten Effekt auf soziales Verhalten bei dauerhafter Anwendung. Dieser Effekt vermag die illegal deponierten Müllmengen an Recyclingsammelstellen um rund ein Drittel zu reduzieren. Weiter kann Gemeinden empfohlen werden, in Unterfluranlagen zu investieren und von den alten, traditionellen Containern abzusehen, da dadurch die Menge deponierten Abfalls deutlich reduziert werden kann.

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Diamonds are known for both their beauty and their durability. Jefferson National Lab in Newport News, VA has found a way to utilize the diamond's strength to view the beauty of the inside of the atomic nucleus with the hopes of finding exotic forms of matter. By firing very fast electrons at a diamond sheet no thicker than a human hair, high energy particles of light known as photons are produced with a high degree of polarization that can illuminate the constituents of the nucleus known as quarks. The University of Connecticut Nuclear Physics group has responsibility for crafting these extremely thin, high quality diamond wafers. These wafers must be cut from larger stones that are about the size of a human finger, and then carefully machined down to the final thickness. The thinning of these diamonds is extremely challenging, as the diamond's greatest strength also becomes its greatest weakness. The Connecticut Nuclear Physics group has developed a novel technique to assist industrial partners in assessing the quality of the final machining steps, using a technique based on laser interferometry. The images of the diamond surface produced by the interferometer encode the thickness and shape of the diamond surface in a complex way that requires detailed analysis to extract. We have developed a novel software application to analyze these images based on the method of simulated annealing. Being able to image the surface of these diamonds without requiring costly X-ray diffraction measurements allows rapid feedback to the industrial partners as they refine their thinning techniques. Thus, by utilizing a material found to be beautiful by many, the beauty of nature can be brought more clearly into view.