Polymerized bovine hemoglobin solution as a replacement for allogeneic red blood cell transfusion after cardiac surgery: Results of a randomized, double-blind trial

AbstractBackground: Blood loss leading to reduced oxygen-carrying capacity is usually treated with red blood cell transfusions. This study examined the hypothesis that a hemoglobin-based oxygen-carrying solution can serve as an initial alternative to red blood cell transfusion. Methods: In a randomized, double-blind efficacy trial of HBOC-201, a total of 98 patients undergoing cardiac surgery and requiring transfusion were randomly assigned to receive either red blood cell units or HBOC-201 (Hemopure; Biopure Corporation, Cambridge, Mass) for the first three postoperative transfusions. Patients were monitored before and after transfusion, at discharge, and at 3 to 4 weeks after the operation for subsequent red blood cell use, hemodynamics, and clinical laboratory parameters. Results: The use of HBOC-201 eliminated the need for red blood cell transfusions in 34% of cases (95% confidence interval 21%-49%). Patients in the HBOC group received a mean of 1.72 subsequent units of red blood cells; those who received red blood cells only received a mean of 2.19 subsequent units (P =.05). Hematocrit values were transiently lower in the HBOC group but were similar in the two groups at discharge and follow-up. Oxygen extraction was greater in the HBOC group (P =.05). Mean increases in blood pressure were greater in the HBOC group, but not significantly so. Conclusion: HBOC-201 may be an initial alternative to red blood cell transfusions for patients with moderate anemia after cardiac surgery. In a third of cases, HBOC-201 eliminated the need for red blood cell transfusion, although substantial doses were needed to produce this modest degree of blood conservation.J Thorac Cardiovasc Surg 2002;124:35-4

Laser line scanning processing system for wrinkling in nation during coating

textOne of the major limiting factors in fuel cell production is the time and effort that are required in the ink coating process of the Nafion film that is at the heart of what makes a fuel cell work. The principle reason that this issued has not been tackled by the industry at large is the inherent difficulties that arise. First and foremost is the rapid and extensive expansion of the material upon contact with the liquid ink causing the Nafion film to wrinkle while being processed. In the drive to help mitigate this issue it must be understood by what conditions and severity that wrinkling occurs. The method chosen to detect this was to develop a laser profile scanner to record and output the severity of any wrinkles present in the film. This thesis showcases and explains the laser scanning system designed specifically for this problem and material.Mechanical EngineeringMechanical Engineerin

Meta-learning and Enforcing Useful Conservation Laws in Sequential Prediction Problems

In recent years, deep learning techniques have enjoyed storied success in a wide array of problem domains, including computer vision, natural language processing, and robotics. While much of this success can be attributed to increasing availability of both data and computing resources, the inductive biases induced by various training methods, model components, and architectures has helped enable efficient generalization as well. Useful biases often exploit symmetries in the prediction problem, such as convolutional neural networks relying on translation equivariance. Automatically discovering such useful symmetries is a promising path to greatly improving the performance of ML systems, but it still remains a challenge. In this work, we focus on sequential prediction problems in real and simulated physical domains and take inspiration from Noether’s theorem to reduce the problem of finding inductive biases to that of meta-learning useful conserved quantities. We propose Noether Networks: a class of models where an unsupervised, meta-learned conservation loss is optimized inside the prediction function. This adapts the model weights to the particular input and imposes the approximate meta-learned conservation law in the predictions. We show, theoretically and experimentally, that Noether Networks improve prediction quality, providing a general framework for discovering inductive biases in sequential prediction problems.M.Eng

Transtracheal jet ventilation: a life-threatening or life-saving device

Jet ventilation through the trachea can cause airway injury and death due to high airway pressure and tension pneumothorax. Intratracheal and intrapulmonary pressures developed in a lung/trachea simulator were measured using a commercial transtracheal jet ventilator coupled with a commercial 12-gauge IV catheter. Intrapleural pressures ranged from 0 to 55 cmH2O as the jet driving pressure was varied from 10 to 54 psi. Simultaneous intratracheal pressures ranged from 4 to 328 cm H2O over the same range of driving pressures. Driving pressure was a linear function of nozzle pressure over a range from 15 to 54 psi. Extreme caution must be exercised when selecting an untested catheter for use with the jet ventilator to minimize the risk of barotrauma. Testing should be performed before placing catheter-jet systems into use

Transcranial Doppler monitoring of carotid artery occlusion during endarterectomy [3] (multiple letters)

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