Dead-blow hammer design applied to a calibration target mechanism to dampen excessive rebound

An existing rotary electromagnetic driver was specified to be used to deploy and restow a blackbody calibration target inside of a spacecraft infrared science instrument. However, this target was much more massive than any other previously inherited design applications. The target experienced unacceptable bounce when reaching its stops. Without any design modification, the momentum generated by the driver caused the target to bounce back to its starting position. Initially, elastomeric dampers were used between the driver and the target. However, this design could not prevent the bounce, and it compromised the positional accuracy of the calibration target. A design that successfully met all the requirements incorporated a sealed pocket 85 percent full of 0.75 mm diameter stainless steel balls in the back of the target to provide the effect of a dead-blow hammer. The energy dissipation resulting from the collision of balls in the pocket successfully dampened the excess momentum generated during the target deployment. The disastrous effects of new requirements on a design with a successful flight history, the modifications that were necessary to make the device work, and the tests performed to verify its functionality are described

A new species of Reticulitermes Holmgren, 1913 (Isoptera: Rhinotermitidae) from the southeastern United States

Reticulitermes nelsonae, a new species of subterranean termite (Isoptera, Rhinotermitidae) is described from Sapelo Island, Georgia, United States of America, with specimens also found in North Carolina and Florida. The adult and soldier castes are described and illustrated to distinguish R. nelsonae from the four described Reticulitermes spp. known to occur in the southeastern United States

The Impact of Foot-and-Mouth Disease (FMD) on Hog, Pork, and Beef Prices: the Experience in Korea

Korea experienced two outbreaks of foot-and-mouth disease (FMD), one in the year 2000 and one in 2002. After the first outbreak, prices for hogs, pork, and beef dropped 15-20% before the government began an intervention program. The effects of these two outbreaks are examined using Box and Tiao's intervention analysis model and a GARCH model Although the second outbreak resulted in many times more animal deaths than the first outbreak, its effect on prices was much smaller. The reason may be because the government's response to the first outbreak set a precedent for the second one.Livestock Production/Industries,

Psychologists Collaborating With Clergy

If a patient adheres to religious values and practices, should the treating psychologist get input from a clergyperson? How frequent is clergy-psychologist collaboration? What obstacles impede such collaboration? An exploratory survey questionnaire was sent to 200 clergy, 200 psychologists interested in religious issues, and 200 psychologists selected without regard to religious interests or values. Four themes were assessed: types of collaborative activities, frequency of collaboration, obstacles to collaboration, and ways to enhance collaboration. Strategies for promoting clergy-psychologist collaboration include challenging unidirectional referral assumptions, building trust through proximity and familiarity, and considering the importance of shared values and beliefs

Methods for evaluating changes in cartilage stiffness following electromechanical reshaping

One common component of otolaryngological surgeries is the reshaping of cartilage. Previous studies have demonstrated the efficient achievement of this procedure through electromechanical reshaping (EMR), a technique that involves the direct application of voltage to cartilage that is mechanically deformed in a jig. Two main parameters, voltage and application time, may be regulated to achieve varying degrees of shape change. Although prior research has correlated these EMR parameters with degree of shape change, it remains necessary to correlate the same parameters with the degree of change in the mechanical properties of tissue. Once this is accomplished, an ideal balance may be determined, in which shape change is maximized while intrinsic tissue damage is minimized This study satisfies this need by providing comprehensive data on the pre- and post-EMR stiffness of both septal and auricular cartilage over a range of voltages (2-8V) with constant application time (2 min for septal, 3 min for auricular). EMR was applied using flat platinum electrodes to one of two 15 mm X 5 mm samples obtained from the same cartilage specimen, while the second sample was maintained as a control. Following a 15 min re-hydration period, the Young's modulus of the tissue was calculated for both the control and experimental sample from data obtained through a uniaxial tension test. A general reduction in stiffness was observed beginning at 3V, with the magnitude of reduction increasing at 6V. © 2010 Copyright SPIE - The International Society for Optical Engineering