Optimal Tolerance Design of a Printer Actuator

In this paper we describe an extension of an existing optimization technique to the tolerance design of a printer actuator mechanism. We provide the designer with a method for selecting optimal nominal design values for the parameters of a generalized system which allows maximum tolerance excursions away from the nominal design values and yet still maintains performance standards. The method uses an interactive linear-programming based design optimization algorithm to select optimal nominal parameter values and their associated maximal tolerances. We illustrate the method with a simple two-dimensional example. Finally we show the results from the tolerance optimization of a printer actuator which demonstrates the applicability of the theory to a real design problem.

Synovial sarcoma with squamous differentiation of its mesenchymal glandular elements. A case report with light-microscopic, ultramicroscopic, and immunologic correlation

A 25-year-old male patient with a biphasic synovial sarcoma of his right flank is reported. The tumor was not only richly glandular but also showed a rare finding in association with a sarcoma, namely, squamous differentiation. Light microscopy and electron microscopy demonstrated the classical features of a biphasic synovial sarcoma except for foci of squamous change. Antibody stain directed against keratin demonstrated this substance in both the glandular and squamous cells but not in the stromal elements. Therefore, the finding of squamous differentiation in association with a malignant, deep soft-tissue tumor must include in the differential diagnosis not only carcinomas but rare sarcomas as well, including the biphasic synovial sarcoma and the glandulosquamous variant of malignant schwanomma.

Alveolar soft part sarcoma following radiotherapy for a spinal hemangioma. A case report

A case of alveolar soft part sarcoma arising some 20 years later in a site previously irradiated as a treatment for a spinal cord hemangioma is described. This is the first known case of radiation-associated alveolar soft part sarcoma, and it fulfills the criteria for a tumor to be radiation-induced. The coincidental finding of "viral-like" particles within some of the tumor cells was noted.

31P NMR spectroscopy of rat organs, in situ, using chronically implanted radiofrequency coils

A technique for making 31P NMR spectroscopic measurements in rat kidney, heart, and liver in vivo is presented. Two-turn solenoid coils were surgically implanted around the organ sufficiently in advance of NMR experiments to allow recovery of the animal. These chronically implanted coils allowed acquisition of high-resolution spectra at 40.5 and 97.3 MHz. No resolution improvement occurred at the higher field. Spectra were stable for up to 24 hr, during which time a variety of experiments could be performed. By accumulating spectra at 10-min intervals, the effects of intraperitoneal fructose injections were monitored; in kidney and liver, a rapid increase in sugar phosphates at the expense of Pi and ATP resulted. Fructose had no effect on heart metabolite levels. Spectra from the heart in vivo were obtained at systole and diastole by gating the spectrometer to the aortic pressure wave; no differences in phosphate metabolites were detected. Finally, saturation transfer techniques were used to monitor the rate of ATP synthesis in the kidney. The unidirectional rate constant for the conversion of Pi to ATP was 0.12 +/- 0.03 sec-1.

Keshan disease-an endemic cardiomyopathy in China

Keshan disease, an endemic cardiomyopathy in China, was prevalent in rural areas located in a long belt region where the selenium content was low in foods. Intervention studies with well controlled subjects revealed a prophylactic effect of sodium selenite. Multifocal necrosis and fibrous replacement of the myocardium characterized the histopathological features and myocytolysis was present in most cases. Ultrastructural observations on twelve postmortem cases revealed remarkable changes in many organelles of which mitochondria appeared to be most important in the development of myocardial lesions. Three kinds of specific granules, which have not been found in other reports on cardiomyopathies, were represented and other factors which might also contribute to the aetiology are discussed.

Electrophysiological correlates of adult decisions made during a conservation of quantity task

Visual evoked responses were recorded from 10 scalp locations over the left and right hemisphere while adults were involved in a conservation of quantity task. Multivariate analyses involving principal components analysis and ANOVA identified bilateral and left hemisphere lateralized components of the visual evoked responses which discriminated between conservation judgments made by subjects.

A medial axis transformation for grayscale pictures

Blum's medial axis transformation (MAT) for binary pictures yields medial axis points that lie midway between opposite borders of a region or along angle bisectors. This note discusses a generalization of the MAT in which a score is computed for each point P of a grayscale picture based on the gradient magnitudes at pairs of points that have P as their midpoint. These scores are high at points that lie midway between pairs of antiparallel edges or along angle bisectors, so that they define a MAT-like ``skeleton,'' which we may call the GRADMAT. However, this skeleton is rather sensitive to the presence of noise edges or to irregularities in the region edges, and it also is subject to artifacts created by pairs of edges belonging to different objects.

Image approximation from gray scale ``medial axes''

Several types of gray-weighted ``medial axes'' have been defined. This paper shows that one of them, the min-max medial axis, can be used to reconstruct good approximations to the original image based on a relatively small amount of information.

Serum iron and total iron-binding capacity compared with serum ferritin in assessment of iron deficiency

Ferritin values for 250 selected sera were compared with values for iron, total iron-binding capacity (TIBC), and transferrin saturation, to assess the potential of the ferritin assay for the detection of latent iron deficiency. The specimens were grouped (50 in each group) according to their values for iron and TIBC. In Group 1 (low iron, high TIBC) the saturation and ferritin values both indicated iron deficiency in all but one. In the 100 specimens of Groups 2 (normal iron, high TIBC) and 4 (normal iron, high normal TIBC), the saturation values revealed 16 iron-deficient cases, the ferritin test 55. For Groups 3 (low iron, normal TIBC) and 5 (low iron, low TIBC), the ferritin test revealed fewer cases of iron deficiency than did the saturation values (37 cases vs 51 cases, in the 100 specimens). Evidently the ferritin test detects iron deficiency in many cases for whom the serum iron and TIBC tests are not positively indicative. The correlation of serum ferritin with iron, TIBC, and transferrin saturation in the five groups was good only in the case of specimens for which the TIBC was normal; if it was abnormal the correlation was very poor.

Serum iron and total iron-binding capacity compared with serum ferritin in assessment of iron deficiency

Ferritin values for 250 selected sera were compared with values for iron, total iron-binding capacity (TIBC), and transferrin saturation, to assess the potential of the ferritin assay for the detection of latent iron deficiency. The specimens were grouped (50 in each group) according to their values for iron and TIBC. In Group 1 (low iron, high TIBC) the saturation and ferritin values both indicated iron deficiency in all but one. In the 100 specimens of Groups 2 (normal iron, high TIBC) and 4 (normal iron, high normal TIBC), the saturation values revealed 16 iron-deficient cases, the ferritin test 55. For Groups 3 (low iron, normal TIBC) and 5 (low iron, low TIBC), the ferritin test revealed fewer cases of iron deficiency than did the saturation values (37 cases vs 51 cases, in the 100 specimens). Evidently the ferritin test detects iron deficiency in many cases for whom the serum iron and TIBC tests are not positively indicative. The correlation of serum ferritin with iron, TIBC, and transferrin saturation in the five groups was good only in the case of specimens for which the TIBC was normal; if it was abnormal the correlation was very poor.

In vitro antagonism of benzodiazepine binding to cerebral receptors by H1 and H2 antihistamines

Antihistamines directed at either the H1 or H2 histamine receptor have the well-known side effect of sedation. The mechanism for the CNS depressant action of antihistamines is unknown. We examine here the possibility that the mechanism may involve modulation of the cerebral benzodiazepine receptor. We demonstrate that cimetidine and pyrilamine are competitive antagonists of 3H-benzodiazepine binding to human cerebral receptor in vitro. The inhibition of radioligand binding was not specific for benzodiazepine receptor, however, since antihistamines also antagonized binding to GABA, opiate, and muscarinic acetylcholine receptor. The interaction of antihistamine with CNS receptors other than histamine receptor may explain, at least in part, the side effect of sedation.