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611.
Approximate methods using ranks for regression with censored data   总被引:1,自引:0,他引:1  
PEITITT  A. N. 《Biometrika》1983,70(1):121-132
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It is not unusual for emergency physicians to quickly identify whether a patient would have wanted to be resuscitated or intubated in a cardiac arrest situation, but patients’ other preferences for end-of-life care or organ donation are less commonly ascertained in the emergency department. Typically, the decision process regarding such goals at end of life may be “deferred” to the intensive care unit. We present a case illustrative of the complexity of discussing organ donation in the emergency department and suggest that patients who die in the emergency department should be afforded the respect and consideration provided in other parts of the hospital, including facilitation of organ transplantation. As circulatory determination of death becomes a more common antecedent to organ transplantation, specific questions may arise in the emergency department setting. When in the emergency department, how should organ donation be addressed and by whom? Should temporary organ preservation be initiated in the setting of uncertainty regarding a patient’s wishes? To better facilitate discussions about organ donation when they arise in emergency settings, we propose increased coordination between organ procurement organizations and emergency physicians to improve awareness of organ transplantation.  相似文献   
614.
《Cell》2022,185(11):1860-1874.e12
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Common species of kelp-bed fishes including adult blacksmith Chromis punctipinnis , adult senorita Oxyjulis californica , and sub-adult kelp bass Paralabrax clathratus were collected from two separate and isolated rocky reefs at Santa Catalina Island, California, U.S.A. where giant kelp Macrocystis pyrifera was present. After tagging, groups of fishes were either returned to their initial collection site or displaced to an alternative kelp-bed site to measure site fidelity and homing behaviour. No tagged fishes that were returned to their initial collection sites and subsequently resighted, exhibited any movement to another reef suggesting that these fishes have a limited home range, and handling during capture and tagging had no effect on site fidelity. Of fishes translocated to alternative kelp-bed sites, up to 80% of tagged senorita and 100% of tagged blacksmith that were resighted had returned to the site of their initial collection, indicating that these species are motivated and able to relocate previously utilized areas when displaced. However, when young-of-the-year and juvenile kelp bass were displaced, none were ever seen again suggesting that disruption of the relationship between a young kelp bass and its home site may influence its survival.  相似文献   
617.
Workability and productivity of robotic plug transplanting workcell   总被引:3,自引:0,他引:3  
Summary Transplanting is a necessary operation in transplant production systems. Transplanting operation is labor-intensive and automation can reduce labor costs. Plugs are actively growing young transplants with two well-defined morphologic parts: the stem-leaf portion and the root-growth medium portion. They may be grown in regularly situated cells on traylike containers. This regularity makes plugs suitable for automated transplanting operations. It is, therefore, beneficial for in vitro plant propagation systems to include plugs as intermediate products before they are delivered to the greenhouses. Flexible automation and robotics technologies have been applied to develop a robotic workcell for transplanting plugs from plug trays to growing flats. Main components of the workcell include a robot, an end-effector, and two conveyer belts for transporting trays and flats. The end-effector for extracting, holding, and planting plugs is a “sliding-needles-with-sensor” gripper. The sensor signals the robot to complete a transplanting cycle only when a plug is properly held by the gripper. Systems analysis and computer simulation were conducted to study factors affecting workability and productivity of various workcell designs. These factors included: dimensions and kinematics of the robot and its peripheral equipment, layout and materials flow, fullness of plug trays, and successful extraction rate of plugs. The analysis also indicated that machine vision systems could add valuable capabilities to the workcell, such as robot guidance and plug quality evaluation. Engineering economic analysis was performed to investigate the interaction of workcell technical feasibility and economic viability. Presented in the Session-in-Depth Robotics in Tissue Culture at the 1991 World Congress on Cell and Tissue Culture, Anaheim, California, June 16–20, 1991.  相似文献   
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