Social and emotional problems in the rehabilitation of cancer patients: a study of 14 patients age 60-75 with cancer of the cervix.

Thesis (M.S.)--Boston Universit

Learning and memory in machines and animals : an AI model that accounts for some neurobiological data

The CEL model of learning and memory (Components of Episodic Learning) [Granger 1982, 1983a, 1983b] provides a process model of certain aspects of learning and memory in animals and humans. The model consists of a set of asynchronous and semi-independent functional operators that collectively create and modify memory traces as a result of experience. The model conforms to relevant results in the learning literature of psychology and neurobiology. There are two goals to this work: one is to create a set of working learning systems that will improve their performance on the basis of experience, and the other is to compare these systems' performance with that of living systems, as a step towards the eventual comparative characterizations of different learning systems.Parts of the model have been implemented in the CEL-0 program, which operates in a 'Maze-World' simulated maze environment. The program exhibits simple exploratory behavior that leads to the acquisition of predictive and discriminatory schemata. A number of interesting theoretical predictions have arisen in part from observation of the operation of the program, some of which are currently being tested in neurobiological experiments. In particular, some neurobiological evidence for the existence of multiple, seperable memory systems in humans and animals is interpreted in terms of the model, and some new experiments are suggested arising from the model's predictions

Small sets of complementary observables

Two observables are called complementary if preparing a physical object in an eigenstate of one of them yields a completely random result in a measurement of the other. We investigate small sets of complementary observables that cannot be extended by yet another complementary observable. We construct explicit examples of the unextendible sets up to dimension $16$ and conjecture certain small sets to be unextendible in higher dimensions. Our constructions provide three complementary measurements, only one observable away from the ultimate minimum of two observables in the set. Almost all of our examples in finite dimension allow to discriminate pure states from some mixed states, and shed light on the complex topology of the Bloch space of higher-dimensional quantum systems

An experimental and analytical investigation of isolated rotor flap-lag stability in forward flight

For flap-lag stability of isolated rotors, experimental and analytical investigations are conducted in hover and forward flight on the adequacy of a linear quasisteady aerodynamics theory with dynamic inflow. Forward flight effects on lag regressing mode are emphasized. A soft inplane hingeless rotor with three blades is tested at advance ratios as high as 0.55 and at shaft angles as high as 20 degrees. In combination with lag natural frequencies, collective pitch settings and flap-lag coupling parameters, the data base comprises nearly 1200 test points (damping and frequency) in forward flight and 200 test points in hover. By computerized symbolic manipulations, an analytic model is developed in substall to predict stability margins with mode identification. It also predicts substall and stall regions to help explain the correlation between theory and data

Thrifty Viability and Traditional Mortgage Lending: A Simultaneous Equations Analysis of the Risk-Return Trade-Off

A number of studies have argued that the thrift industry is not viable as it is presently structured and regulated because mortgage yields are inadequate to cover interest and operating costs. This hypothesis suggests that observed profitability is primarily the result of the tendency of the industry to "ride" the yield curve by borrowing short and lending long. To evaluate this argument, we construct a simultaneous-equations model of thrift risk (maturity gap positions) and return (net interest margin). We find support for the notion that the industry could not be reasonably profitable if it did not take on significant interest-rate risk. For instance, a zero gap position produces a return on assets of only 19 basis points and a return on equity of only 4%. We also estimate the amount of interest-rate risk the industry can employ to increase returns on equity and assets. Our estimates show that over 50% of thrift profits earned during this period are the result of negative gap positions and interest-rate speculation. As earlier research shows, changes in regulations affecting thrift asset and liability choices can be counterproductive.

The Hartford Female Beneficent Society and the Hartford Orphan Asylum: A Case Study from 1810 to 1890

Dedicated to Eugene Leach, Ph

Contaminant removal from enclosed atmospheres by regenerable adsorbents

A system for removing contaminants from spacecraft atmospheres was studied, which utilizes catalyst-impregnated activated carbon followed by in-situ regeneration by low-temperature catalytic oxidation of the adsorbed contaminants. Platinum was deposited on activated carbon by liquid phase impregnation with chloroplatinic acid, followed by drying and high-temperature reduction. Results were obtained for the seven selected spacecraft contaminants by means of three experimental test systems. The results indicate that the contaminants could be removed by oxidation with very little loss in adsorptive capacity. The advantages of a catalyst-impregnated carbon for oxidative regeneration are found to be significant enough to warrent its use

Characteristic Mechanisms and Outcome of Cardiopulmonary Arrest in Congestive Heart Failure Patients

Recent studies suggest the mechanism of sudden death in congestive heart failure (CHF) patients is less frequently VT/VF than previously believed. In order to further understand the characteristics and mechanisms of death in CHF patients, we evaluated 146 patients who underwent cardiopulmonary resuscitation during hospitalization for congestive heart failure, ischemic heart disease, and noncardiac causes. Clinical characteristics and outcomes are described below:CHF/CardiacnonCHF/CardiacnoncardiacN302690Age63 (49.71)67 (60.72)63 (29.71)Sex (% male)375860Initial Rhythm N(%)VT/VF7 (25)11 (44)24 (27)Asystole6 (21.4)6 (24)33 (37.5)Bradycardia5 (17.9)2 (8)6 (6.8)EMD6 (21.4)1 (4)13 (148)Other4 (14.3)5 (20)12 (136)ROSC21 (70)13 (50)51 (56.7)Survival to D/C1 (3.3)4 (15.4)2 (2.2)Patients with nonCHF/Cardiac disease had a higher ROSC than patients with CHF and noncardiac diseases (p=0.016). In summary, patients with CHF often experience cardiopulmonary arrest with bradycardic or EMD arrests. Although patients with CHF are resuscitated with a high degree of success their in-hospital survival was low. Furthermore, the high rate of bradycardic and EMD arrests may explain the low in-hospital survival rates