Absorption edge and energy gap of anodic oxide films on bismuth

The absorption edge, energy gap and transition type have been determined for anodic films on bismuth, obtained in two types of electrolytes. The first, a glycol borate electrolyte, is representative of electrolytes that form “pure” films, and the other, a phosphate solution, is assumed to incorporate anions into the film. This incorporation was found to decrease the effective energy gap and to change the transition type.     

Results of proximal tibial osteotomy. The effects of tibiofemoral angle, stance-phase flexion-extension, and medial-plateau force

Forty-eight knees were evaluated after proximal tibial osteotomy, performed for varus deformity to determine the desired amount of correction of the deformity, the effect of osteotomy on knee motion during gait and one medial-plateau force during standing, and the relationships between these factors and the result. Correction of the tibiofemoral angle to 5 degrees of genu valgum or more produced the best and most lasting results. Stance-phase flexion-extension increased the rotation decreased in knees with good results while the other gait parameters were not significantly changed. Medial-plateau force was decreased by successful tibial osteotomy. The knees with the best and most lasting results had 7 degrees of stance-phase flexion-extension or more during walking and either a valgus tibiofemoral angle of 5 degrees or more or a medial-plateau force of 50 per cent of body weight or less.     

Initial studies on the penetration of spirohydantoin mustard into the cerebrospinal fluid of dogs

The possible correlations between unipolar endocardial electrogram amplitudes and voltage threshold stimulation were tested with electrodes having metallic tips of two different areas. The threshold measurements were always studied with the same pulse characteristics. The data were analyzed through five mathematical functions (linear, exponential, potential, hyperbola and translate hyperbola). The results show a significant correlation, mainly by hyperbolic and exponential functions. Consequently, we could deduce a parameter value since we already knew the other one. This was possible not only during the first implantation, but also later on.     

The effect of method of preparation on the corrosion resistance and catalytic activity during corrosion of tungsten carbide II. Changes in the catalytic activity of tungsten carbides during the corrosion process

Sedimented electrodes were used for the investigation of the changes in the catalytic activity during corrosion in 4.5 and 9.9N H₂SO₄ of tungsten carbides synthesized under different conditions. It is shown that during corrosion the specific activity of all the samples studied reaches a maximum after a certain exposure time. The same phenomenon is observed also during the periodic contact of the corroding samples with hydrogen. The catalytic activity decreases with increase in the quantity of tungsten oxides formed during corrosion. In 4.5N H₂SO₄ the specific activity of the tested samples is subjected to more pronounced changes. Corrosion processes lead to some exceptions in the general rule that carbides synthesized from WO₃ display a higher specific activity than those synthesized from H₂WO₄ (w).     

Breast reconstruction for malignant or premalignant disease

In ten patients breast reconstruction was done after surgical treatment for a premalignant or malignant breast disease. In six of these, prophylactic subcutaneous mastectomy and implant reconstruction were carried out, and in the remaining four reconstruction was done after simple or modified radical mastectomy. It is suggested that these procedures should be considered by those physicians and surgeons who undertake evaluation and treatment of breast disease in women. Breast reconstruction should be considered and offered to patients who suffer from the severe personal and emotional trauma attendant to surgical operation for breast disease.     

Esophageal perforation following use of esophageal airway

The esophageal airway has gained increasing acceptance in airway management during cardiopulmonary resuscitation, and its enthusiastic advocates are urging expansion of its use. A fatal case of esophageal perforation following the use of an esophageal airway is presented. Possible contributing factors are discussed. A modified esophageal airway which seems safer and more versatile, effective, and economic is described.     

Patterns of ambulatory health care in five different delivery systems

Few empirical investigations permit systematic comparison of the impact of widely-varying delivery systems within a single population sample. This study provides such a comparison, describing patterns of ambulatory care among patients using five different systems in Washington, D.C. as a regular source of health care: solo practice, fee-for-service group practice, prepaid group practice, public clinics, and hospital outpatient departments or emergency rooms. Comparisons are adjusted statistically to account for major patient group variations, and the results reveal substantial differences among the five systems. Sources used primarily by the poor--hospital outpatient departments, emergency rooms, and public clinics--contained important structural and financial barriers, and had the lowest rates of patient-initiated use. The prepaid system, in contrast, maximized patient's access to both preventive care and symptomatic care, and did not seem to inhibit physician-controlled follow-up care. The results suggest some perverse effects of fee-for-service payment: patients, especially poor patients, appeared to be deterred from seeking preventive and symptomatic care, while physicians were encouraged to expand follow-up services. Moreover, services in fee-for-service systems were distributed less equitably relative to both income and medical need than in the prepaid system. These findings have direct implications for policy decisions concerning organizational and financial arrangements for the delivery of ambulatory care.