Duties of Members, Directors, and Managers of Cooperative Associations

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A Review of Micro-Contact Physics for Microelectromechanical Systems (MEMS) Metal Contact Switches

Innovations in relevant micro-contact areas are highlighted, these include, design, contact resistance modeling, contact materials, performance and reliability. For each area the basic theory and relevant innovations are explored. A brief comparison of actuation methods is provided to show why electrostatic actuation is most commonly used by radio frequency microelectromechanical systems designers. An examination of the important characteristics of the contact interface such as modeling and material choice is discussed. Micro-contact resistance models based on plastic, elastic-plastic and elastic deformations are reviewed. Much of the modeling for metal contact micro-switches centers around contact area and surface roughness. Surface roughness and its effect on contact area is stressed when considering micro-contact resistance modeling. Finite element models and various approaches for describing surface roughness are compared. Different contact materials to include gold, gold alloys, carbon nanotubes, composite gold-carbon nanotubes, ruthenium, ruthenium oxide, as well as tungsten have been shown to enhance contact performance and reliability with distinct trade offs for each. Finally, a review of physical and electrical failure modes witnessed by researchers are detailed and examined

Critical soft landing technology issues for future US space missions

A programmatic need for research and development to support parachute-based landing systems has not existed since the end of the Apollo missions in the mid-1970s. Now, a number of planned space programs require advanced landing capabilities for which the experience and technology base does not currently exist. New requirements for landing on land with controllable, gliding decelerators and for more effective impact attenuation devices justify a renewal of the landing technology development effort that existed during the Mercury, Gemini, and Apollo programs. A study was performed to evaluate the current and projected national capability in landing systems and to identify critical deficiencies in the technology base required to support the Assured Crew Return Vehicle and the Two-Way Manned Transportation System. A technology development program covering eight landing system performance issues is recommended

Alien Registration- Mcbride, George W. (Fort Fairfield, Aroostook County)

https://digitalmaine.com/alien_docs/36517/thumbnail.jp

Dysregulation of cadherins in the intercalated disc of the spontaneously hypertensive stroke-prone rat

The structural integrity of cardiac cells is maintained by the Ca2+-dependent homophilic cell-cell adhesion of cadherins. N-cadherin is responsible for this adhesion under normal physiological conditions. The role of cadherins in adverse cardiac pathology is less clear. We studied the hearts of the stroke-prone spontaneously hypertensive (SHRSP) rat as a genetic model of cardiac hypertrophy and compared them to Wistar-Kyoto control animals. Western blotting of protein homogenates from 12-week old SHRSP animals indicated that similar levels of [beta], [gamma]-, and [alpha]-catenin and T, N and R-cadherin were expressed in the control and SHRSP animals. However, dramatically higher levels of E-cadherin were detected in SHRSP animals compared to controls at 6, 12 and 18áweeks of age. This was confirmed by quantitative Taqman PCR and immunohistochemistry. E-cadherin was located at the intercalated disc of the myocytes in co-localisation with connexin 43. Adenoviral overexpression of E-cadherin in rat H9c2 cells and primary rabbit myocytes resulted in a significant reduction in myocyte cell diameter and breadth. E-cadherin overexpression resulted in re-localisation of [beta]-catenin to the cell surface particularly to cell-cell junctions. Subsequent immunohistochemistry of the hearts of WKY and SHRSP animals also revealed increased levels of [beta]-catenin in the intercalated disc in the SHRSP compared to WKY. Therefore, remodelling of the intercalated disc in the hearts of SHRSP animals may contribute to the altered function observed in these animal