Comparison of measurements of the characteristics of directional microphone hearing aids in an IAC test room and an anechoic chamber

The purpose of this study was to assess the possibility of measuring directional microphone hearing aids (DMHAs) using standard hearing aid test instruments in a sound field environment. The use of DMHAs is increasing and research has shown that under certain difficult listening situations, superior results are obtained by hearing impaired individuals with directional versus omnidirectional microphone arrangements. However, valid electroacoustic evaluation of the DMHAs cannot be accomplished using the conventional hearing aid test box. The ideal environment for such evaluations is an anechoic chamber, a facility not found in most audiological clinics. Results show that if the proper precautions are observed, the electroacoustic characteristics of DMHAs can be measured in a sound field environment using conventional hearing aid test instrumentation. Validation of this procedure was carried out by comparing sound field results with those obtained in an anechoic chamber.     

Group psychotherapy with mastectomy patients.

Compared 20 women who participated in 10 weekly sessions of group psychotherapy with 20 women placed on a waiting list after they had mastectomies. Ss were matched on age (33–65 yrs old), marital status, time since surgery, prognosis, and SES. A structured, scaled interview was used to assess maladjustment, and 2 inventories were used to assess therapy outcome; all Ss were administered all measures before the treatment program began, when it finished 10 wks later, and 4 wks after the end of treatment. Results show that over the course of the therapy period, both groups showed changes in a positive direction; however, Ss in the treatment group showed significantly greater improvement. In the 4-wk follow-up period Ss in the treatment group continued to show significant positive change. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Review: transmission scanning electron microscopy

The availability of scanning attachments for transmission microscopes and the advent of very high resolution scanning microscopes now enables materials to be studied in both the back scattered and transmission scanning modes. It is the purpose of this review to present in outline the subject of transmission scanning microscopy, the advocated advantages in comparison with conventional transmission microscopy and some of the achieved and potential applications.     

A bend-testing stage for the scanning electron-microscope

The design of a stage to bend materials in a scanning electron-microscope (Stereoscan, Cambridge Scientific Instruments Ltd) is described together with examples of its use in the fracture of composite materials. The bend module, when fitted to a large modular stage, can be used with existing scanning electron microscopes and is capable of bending, under increasing load or cyclic loading conditions, rectangular specimens of a maximum size 44×4×1.5 mm, to a maximum strain of 1.5%. Using the module with a standard display system the non-catastrophic stages of deformation and failure can be followed at higher magnification than has previously been possible. When the module is used in conjunction with a fast scanning and display system, deformation and fracture processes may be recorded at high magnifications while the specimen is being strained.At present on leave of absence at Cavendish Laboratory, Cambridge.Patent applied for.     

The artificial heart. Progress and promise

A multidisciplinary group has designed, fabricated, and evaluated an artificial heart. The heart consists of two smooth-surfaced sac-type pumps, two pneumatic power units, and an electronic control system. The artificial heart has been employed in 22 calves. A variety of problems have been encountered and overcome and a significant improvement in pump design has been made. As a result, a gradual increase in survival times has occurred. The last two calves in which the heart was tested lived for 60 and 42 days respectively. These animals ate well and gained weight. The ability of the control system to balance the output of the two pumps over long periods of time and to automatically increase cardiac output with treadmill exercise has been confirmed. No insurmountable problems in the development of the artificial heart have been identified. The date that an artificial heart will be available for clinical use depends on the availability of funds and on the tenacity of the investigators.     

Machakos project studies. Agents affecting health of mother and child in a rural area of Kenya. XXII. Schistosomiasis transmission in relation to some socio-economic and other environmental factors

A schistosomiasis research project, carried out in part of the Machakos area, yielded data by which it was possible to relate household egg outputs to some socioeconomic and other environmental variables. A significant negative correlation with schistosome scores was found for most variables when tested individually. Multiple regression analysis revealed a relatively strong relation with altitude and a much weaker association with some other variables. It is discussed whether the influence of altitude may be explained by differences in temperature, 'distance from infected water', or both. Furthermore it is hypothesized whether relations with social and economical variables are due to the fact that members of wealthier families stay away from contaminated water more often, have more knowledge of schistosomiasis and differ in hygienic behaviour.     

Kinetics of coke formation from coal solutions

The reaction kinetics for the formation of mesophase from coal solutions has been studied under conditions similar to those experienced in a delayed coker preheater coil, i.e. at temperatures from 475 to 525 °C approached at high heating rates. The degree of polymerization of the heat-treated materials has been assessed by their solubility in two solvents, cyclohexane and quinoline. An approximation has been made in order to make a kinetic analysis for the formation of insolubles in a non-isothermal system. It has been found that the polymerization of the dissolved coal component, as evidenced by the formation of quinoline insolubles during the heat-treatment of concentrated coal solutions, is essentially a second-order reaction with an apparent activation energy of ≈190 kJ mol^?1. The formation of cyclohexane insolubles from the diluent oil is a slower reaction showing first-order kinetics.     

Addition of neutron and gamma-ray fractions for intestinal damage

The microcolony assay technique has been used to test the validty of summing equivalent doses per fraction of 14 MeV neutrons and gamma rays for mouse intestinal damage. For a 4-daily fraction schedule, in which the first one or two fractions are given as neutrons and the remainder as gamma rays, combined dose fractions calculated from a 4-fraction schedule of either radiation type alone produce the same level of damage within the limits of accuracy of the experiment.