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Swelling of low rank coals due to solvent contact is measured for a suite of such coals from different sources. The method is a simple one: the pouring of solvent on to samples of the coal in glass tubes and measurements of coal height before and after pouring on the solvent. Correlations between swelling and coal properties are discussed, and for one of the coals a ‘swelling spectrum’, displaying swelling as a function of solvent solubility parameter, is presented.

The stiffness of the rail pad is a critical parameter in determining the noise from the track. Both theoretical and experimental studies show that a stiff pad, by coupling the rail to the sleeper, leads to a high attenuation of rail vibration with distance along the track and an increase in the sleeper vibration. In this way the rail-radiated component of noise is reduced but the sleeper component is increased. Conversely a soft pad leads to a low sleeper noise component but greater rail noise, as the rail can vibrate over a greater length. In modern track, soft pads are used, as they lead to reduced track forces and less damage to track components such as sleepers. In this paper, measured vibration characteristics of track are presented and compared with predictions. A recent study of the effect of the load dependence of the rail pad and ballast stiffnesses on the dynamic behaviour of the track is extended to give a practical assessment of the effects on the noise radiation. It is shown that, for a typical soft pad with a high load dependence, neglect of the preloading effect would lead to a significant overprediction of the track noise component. It is thus shown that soft pads need not be so disadvantageous for noise as has been suggested.

A suite of brown coals from different sources was examined for solvent-induced swelling in two forms: oven-dried whole coal and pyridine-extraced coal. This enabled the swelling to be resolved into the component due to imbibition of solvent by the crosslinked part and the component due to the non-crosslinked part.

Objective: The purpose of this multicenter, add-on, double-blind, randomized, active-control study was to compare the efficacy and safety of presumably therapeutic (high) vagus nerve stimulation with less (low) stimulation. Background: Chronic intermittent left vagus nerve stimulation has been shown in animal models and in preliminary clinical trials to suppress the occurrence of seizures. Methods: Patients had at least six partial-onset seizures over 30 days involving complex partial or secondarily generalized seizures. Concurrent antiepileptic drugs were unaltered. After a 3-month baseline, patients were surgically implanted with stimulating leads coiled around the left vagus nerve and connected to an infraclavicular subcutaneous programmable pacemaker-like generator. After randomization, device initiation, and a 2-week ramp-up period, patients were assessed for seizure counts and safety over 3 months. The primary efficacy variable was the percentage change in total seizure frequency compared with baseline. Results: Patients receiving high stimulation (94 patients, ages 13 to 54 years) had an average 28% reduction in total seizure frequency compared with a 15% reduction in the low stimulation group (102 patients, ages 15 to 60 year; p = 0.04). The high-stimulation group also had greater improvements on global evaluation scores, as rated by a blinded interviewer and the patient. High stimulation was associated with more voice alteration and dyspnea. No changes in physiologic indicators of gastric, cardiac, or pulmonary functions occurred. Conclusions: Vagus nerve stimulation is an effective and safe adjunctive treatment for patients with refractory partial-onset seizures. It represents the advent of a new, nonpharmacologic treatment for epilepsy.

Poor diabetic control was found in nearly 50% of adolescents attending two paediatric clinics. Adolescents with well and poorly controlled diabetes differed in reported parental involvement in their diabetic regime. There was little association between glycaemic control and family functioning using the McMaster Family Assessment Device (FAD) whether rated by adolescent or a parent. Neither did sufferers with diabetes differ from families of matched community controls according to the FAD overall though the families of well controlled diabetics were more likely than the other two groups to score themselves in the unhealthy range on the subscale of global functioning.

The swelling of a low-rank coal under the influence of various solvents is examined and results compared with those for a similar coal in briquetted form. Results are interpreted in terms of the effects of briquetting on pore structure.

We sought to determine whether the recently reported decreased incidence of stroke and atherosclerotic disease in a university hospital-based Parkinson's disease patient population would be demonstrated in our patient population. We performed a retrospective case-control review of the last 119 Parkinson's disease patients discharged from the Middleton Veterans Affairs Hospital Neurology Service to study the incidence of ischemic stroke, myocardial ischemia, tobacco use, and other stroke risk factors. Controls were age and sex matched and were randomly taken from 238 non-Parkinson's disease discharges in which stroke or myocardial infarction was not the reason for hospitalization. The cumulative incidences of ischemic stroke, hypertension, and diabetes mellitus were not significantly different between groups. Myocardial infarction, coronary artery disease, tobacco use, atrial fibrillation, cancer, and ethanol abuse were significantly more prevalent in the controls, whereas dementia and congestive heart failure were the only variables studied that were more prevalent in the Parkinson's disease patients. Our study failed to demonstrate that Parkinson's disease patients from a Veteran population were protected from ischemic stroke.

Rolling noise from trains is radiated by both wheel and track vibrations, the track being dominant in many cases. The stiffness of the rail fastener system, especially the elastomeric rail pad usually inserted between the rails and the sleepers, has a significant influence on the noise emitted by the track. Railways are increasingly using softer pads to reduce potential damage to sleepers and ballast. Softer pads decouple the rail from the sleeper. This reduces the noise from the sleeper but also reduces the decay of vibration with distance along the rail and hence leads to an increase of the noise radiated by the rail. The paper describes experimental and theoretical work to investigate the influence of pad stiffness on the dynamic and acoustic behavior of track. The vibrational behavior has been measured on a dedicated 36‐m section of railway track, with different types of rail pad installed. The results are compared with predictions using theoretical models of the track behavior. This allows the effective pad stiffness and damping to be determined, laboratory measurements also being available for comparison. The attenuation of vertical and lateral vibration along the track is measured in order to estimate the effect on radiated noise.

The effect of plasma from normotensive and hypertensive subjects on the binding of [3H]ouabain on human erythrocytes was investigated. The binding of [3H]ouabain on human erythrocytes was saturable and highly specific; linear Scatchard plots indicated the presence of a single type of binding site. Human plasma decreased the binding of [3H]ouabain on its receptor to a greater extent than could be accounted for by the plasma potassium concentration. The level of this circulating ouabainlike factor (or factors) was quantitated using a radioreceptor assay. Plasma from 22 hypertensive subjects (systolic blood pressure greater than 160 mm Hg or diastolic blood pressure greater than 90 mm Hg) displayed higher levels than that from 24 normotensive subjects; furthermore there was a positive and significant correlation (r = 0.42, n = 46, p less than 0.004) between the ouabainlike content and the individual subject's systolic blood pressure. The receptor assay described is relatively simple and should be useful for further work on the nature and clinical importance of the endogenous ouabainlike factor.

PULLORUM disease has been recognized as one of the most costly diseases of poultry. The National Poultry Improvement Plan has as one of its main objectives the eradication of this disease. One of the most common means of transmitting the disease is through the egg. The control measures at present consist of blood testing the breeding flocks, hatchery sanitation, and good management practices. Blood testing of breeding flocks is time consuming and costly. The breeders reacting to the test are sold for meat at a loss to the producer. While the blood test is the best control measure, it is not 100 percent effective. Outbreaks of the disease may occur in flocks previously found to be negative. Repeated tests are necessary to control the infection. Sulfamerazine and sulfadiazine have been found effective in the control of pullorum disease in chicks. Severens, Roberts and Card (1945) report that sulfamerazine (0.5 percent) . . .

PULLORUM disease is of great economic importance to the poultryman. Much progress has been made in the control and eradication of this disease by means of the blood test; however, outbreaks of the disease still occur indicating that the materials used in testing and/or testing methods must be improved. In order to aid the poultryman where acute outbreaks of pullorum disease occur various sulfonamides which may be of benefit have been investigated. Severens, Roberts and Card (1945) found that 0.5 percent sulfamerazine or 2 percent sulfadiazine protected a high percentage of chicks exposed to artificial inoculation of Salmonella pullorum. Mullen (1946) reported that 0.5 percent sulfamerazine in the feed reduced the mortality in turkey poults naturally infected with S. pullorum. Anderson (1946) reported that 0.5 percent sulfamerazine in the feed reduced the mortality in chicks that were naturally infected with S. pullorum. Mattis, et al. (1946) found that no significant . . .

The planning of treatment for patients with gynaecological cancer undergoing combined intracavitary and external beam irradiation at the Royal Marsden Hospital is described. The purpose of the external beam irradiation is to increase the dose to the parametria and pelvic nodes since these tissues are generally too far from the intracavitary 137Cs sources to receive a tumoricidal dose. The treatment policy and problems of dosimetry are discussed. The main problem is to combine the two modes of radiotherapy so as to ensure an adequate dose to the required regions and to afford protection to previously irradiated areas. The method of computing the dose distribution from the intracavitary 137Cs sources is described and also how this distribution is used to design protective absorbers for use with the external beam therapy. Different shapes of absorbers are required for cobalt units and linear accelerators because of the different beam characteristics. The way in which these are designed for individua...

The use of radioactive yttrium (90Y) is reviewed as an alternative to 198Au for malignant effusions. Fifteen cases were treated by intracavitary injection of a new compound, colloidal yttrium silicate. Of nine patients surviving longer than one month, six received good palliation for periods ranging from five to 19 months. The intracavitary retention and extracavitary dosage are detailed and compared with those of other yttrium preparations and with gold.

Abnormalities of calcium binding and calcium transport in cells from hypertensive subjects or animals have been previously described. Total cell sodium is reported to be increased in white blood cells from hypertensive subjects; thus by analogy with Blaustein's proposal for the vascular smooth muscle cell, mononuclear leucocyte cytosolic calcium might be increased via a reduction of the Na-Ca exchange. Using the fluorescent calcium indicator, quin 2, cytosolic calcium was measured in mononuclear leucocytes from 22 hypertensive and 19 normotensive subjects. There was no significant difference between the mononuclear leucocyte cytosolic calcium level in the two groups. Incubation of the cells with 10(-4) M ouabain reduced 86 rubidium (86Rb) uptake by 80% of the control value but failed to alter cytosolic calcium. These findings are consistent with a minimal role of the Na-Ca exchange in the mononuclear leucocyte and may explain why the cytosolic calcium was not increased in hypertension despite the previous reports of increased total cell sodium in white blood cells.

Since the introduction by Mayneord in 1940 [1] of the concept of integral dose, each new technique of radiotherapy has been subject to scrutiny from this point of view. Treatment with electron beams clearly produces an appreciably lower integral dose for very superficial tumours but as we go deeper into the body and the necessary electron energy increases the matter is not so simple.

Injections of male accessory gland material fromAedes aegypti into the hemocoeles of virgin female mosquitoes indicate that the potency of the secretion is equivalent to the amount of semen which a male normally places within the female. This estimation is far less than had been previously calculated. It is suggested that the termmatrone for male accessory gland material is inappropriate since it does not convert a maid into a matron but prevents reinsemination of an impregnated female.

Morphological and physiological evidence indicate that lipid yolk in the mosquito is synthesized only within the oocyte within dense fields of free ribosomes. It does not come from the fat body or any other exogenous source.

To the Editor.— The article by Edward D. Kalat, MD, and David B. Martin, MD (1981;246:982), suggested that a granulomatous reaction in the liver after jejunoileal bypass was favorably influenced by reanastomosis. The accompanying editorial supported this interpretation by stating that "the granulomatous nontuberculous disorder of the liver after J-I [jejunoileal] bypass presumably resolves with restoration of bowel continuity and weight gain." Our recently published article 1 consisting of an evaluation of 30 persons (from a group totaling 84 patients) on whom 101 liver biopsies were obtained at surgery and from three to nine years after jejunoileal bypass would not support the need for reanastomosis. In this study granulomas identical to those found by Drs Kalat and Martin were found initially on four biopsy samples and were not found in the later biopsy specimens, while two patients had granulomas on follow-up biopsies alone, with mild inflammation observed in all cases. Thus