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Background: Very-long-baseline interferometry (VLBI) is a technique employed in radio astronomy where a signal from a planetary radio source is collected on earth at multiple radio antennae. Working in a network, the time difference of the radio signal reception by the antennae is employed to achieve an effective aperture allowing for the development of a significantly high-resolution images of the space. However, the signal clarity of each individual antenna is dependent on its structural response under environmental conditions. This paper proposes a design optimization framework for VLBI antennae for their performance maximization under aerodynamic gust employing structural geometric nonlinearities. Purpose: The dynamic aeroelastic response of the antenna is attenuated by optimizing actuation length changes in active structural elements to improve the pointing accuracy of the VLBI antenna under wind gust loads. No framework currently exists in the open literature that leverages the principles of tensegrity structures for vibration attenuation of VLBI antenna using control actuations, therefore, the need for such a framework has been established to design high-performance VLBI ground stations. Methods: Dynamic aeroelastic gust analysis is performed considering the Power Spectral Density (PSD) with the Davenport spectrum (DS) statistical model and Tuned Discrete Gust analysis with a One-Minus Cosine gust profile. Analyses are performed for two different operating conditions using time-consistent loads (TCL) and time-consistent displacements (TCD). Results: A case study was presented to showcase the proposed framework. A reduction of 82.6% with a total strain energy increase of 292.5% was obtained for the primary operating case under PSD gust excitation. On the other hand, at the increased mean wind speeds of the secondary operating case, the developed design algorithm was able to reduce the total pointing error by 80.9% but with a total strain energy increase of 825.3%. Similarly, for TDG analysis with the OMC excitation profile the optimization algorithm reduced the total pointing error by 51.6% with a TSE increase of 2098.1% and 80.5% with a TSE increase of 48.7% for the primary and secondary operating conditions, respectively, when compared to the uncontrolled response. Conclusion: It is found that in all subcases analyzed the developed optimization framework successfully found the best response of the antenna using the utopian point method. These results confirm the effectiveness of the proposed method.

The mixture of higher product complexity and shorter technology lifecycles conveys that commercializing nascent technologies is likely to play a more important role in new product development. In Sony's commercialization of laser diodes, coordination is promoted between research and development by using internal research symposia and technology expositions. The company expedites technology commercialization by moving project team members from research to development and making those members be responsible for implementation.

The rarity of the magician's throwing cards and their value as advertisements have driven the market for these collector's items. A single throwing card of magician T. Nelson Downs can fetch a price of $50.

Posters of famous magicians from the late 1800s to early 1900s have become valuable collectors' items. These include posters of Houdini, Carter the Great, George, Alexander and Virgil.

We examined four healthy men who developed cilioretinal artery occlusion associated with central retinal vein occlusion. Unlike previously reported patients with this clinical entity, there appeared to be abnormal central retinal artery inflow, as evidenced by prolonged, irregular filling of the branch retinal arteries with intravenous fluorescein angiography. The patients were treated with systemic corticosteroids. All of the patients had initial improvement in vision. However, three of the four patients had recurrent episodes of visual loss. The final visual acuity was 20/40 or better in three of the four patients.

Asteroid hyalosis is a disorder of the vitreous humor (the clear watery fluid contained within the transparent jelly-like mass that fills the cavity of the eyeball behind the crystalline lens of the eye), in which spherical white bodies (calcium salts) are suspended in the vitreous. This ocular condition has been associated with several systemic diseases. A study was undertaken to clarify the relationship between asteroid hyalosis and diabetes, and other systemic diseases. Of 12,205 individuals who underwent routine eye examination; 101 (0.83 percent) were diagnosed with asteroid hyalosis. A control group of 101 patients were matched by age to this group; the average age in both groups was 70. Diabetes was present in 29 percent of the study group, compared with 10 percent of the control group. There was also an increased incidence of systemic high blood pressure in the study group (61 percent) compared with the control group (29 percent). Atherosclerotic vascular disease (characterized by the formation of plaques on the walls of the vessels) was present in 30 percent of the study group, compared with 13 percent of the control group. An additional finding was that the study group was more farsighted than the control group. Asteroid hyalosis appears to be related to the aging process; it is rarely seen in patients under 50. There is evidence that this condition is associated with the vascular and microvascular changes, which occur as a part of the aging process. (Consumer Summary produced by Reliance Medical Information, Inc.)