2,197 research outputs found
Plated nickel wire mesh makes superior catalyst bed
Porous nickel mesh screen catalyst bed produces gas evolution in hydrogen peroxide thrust chambers used for attitude control of space vehicles. The nickel wire mesh disks in the catalyst bed are plated in rugose form with a silver-gold coating
"You Tides with Ceaseless Swell": A Reading of the Manuscript
Argues against common, negative assumptions about Whitman\u27s later poetry by defending the value of Whitman\u27s eight "Fancies at Navesink" poems; compares the published versions to manuscript drafts of the poems to demonstrate that Whitman, in his later years, "reached a level of formal art that had eluded him before.
Brown-Eyed Allie
https://digitalcommons.library.umaine.edu/mmb-vp/3045/thumbnail.jp
A Newly Discovered Image of Walt Whitman Restored by the Walt Whitman Association and the Mickel Street Review
Reprints a newly restored image of Whitman apparently related to the series of photographs taken of the poet by Frederick Gutekunst of Philadelphia in 1889
A Prototype System for Measuring Microwave Frequency Reflections from the Breast
Microwave imaging of the breast is of interest for monitoring breast health, and approaches to active microwave imaging include tomography and radar-based methods. While the literature contains a growing body of work related to microwave breast imaging, there are only a few prototype systems that have been used to collect data from humans. In this paper, a prototype system for monostatic radar-based imaging that has been used in an initial study measuring reflections from volunteers is discussed. The performance of the system is explored by examining the mechanical positioning of sensor, as well as microwave measurement sensitivity. To gain insight into the measurement of reflected signals, simulations and measurements of a simple phantom are compared and discussed in relation to system sensitivity. Finally, a successful scan of a volunteer is described
Friction and leakage characteristics of confined, reduced-scale inflatable structures
This work is focused on the evaluation of the performance of a small-scale inflatable, or plug, placed in a confined space provided by a circular rigid pipe as a way to contain the propagation of floods. The rigid pipe is a simplified and scaled approximation of an actual tunnel section. The evaluations were conducted using an inflatable plug made of a single layer of coated Vectran® fabric. Friction coefficients of the system were calculated for three different materials lining the pipe so a comparison could be made. These friction coefficients were also compared to laboratory friction machine testing of the same lining materials. This comparison showed that the friction coefficients of the pipe-plug system were lower than the laboratory friction machine tests. Rates of water leakage around the plug were also studied. The leakage rates were recorded for several different plug pressures while varying the tunnel pressure accordingly. It was observed that as pressure differential decreased between the plug and pipe, the leakage rate increased. Results showed also that the plug was able to withstand a pressure differential with manageable water leakage rates
Extracellular Vesticles in Acute Respiratory Distress Syndrome: Understanding Protective and Harmful Signaling for the Development of New Therapeutics
Acute respiratory distress syndrome (ARDS) is a severe respiratory condition characterized by increased lung permeability, hyper-inflammatory state, and fluid leak into the alveolar spaces. ARDS is a heterogeneous disease, with multiple direct and indirect causes that result in a mortality of up to 40%. Due to the ongoing Covid-19 pandemic, its incidence has increased up to ten-fold. Extracellular vesicles (EVs) are small liposome-like particles that mediate intercellular communication and play a major role in ARDS pathophysiology. Indeed, they participate in endothelial barrier dysfunction and permeability, neutrophil, and macrophage activation, and also in the development of a hypercoagulable state. A more thorough understanding of the variegated and cell-specific functions of EVs may lead to the development of safe and effective therapeutics. In this review, we have collected evidence of EVs role in ARDS, revise the main mechanisms of production and internalization and summarize the current therapeutical approaches that have shown the ability to modulate EV signaling
- …