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Publisher Summary Climate or meteorological induced cycles are associated with weathering processes of building stone for a long time. Freeze-thaw cycles have severe effects on stone disintegration. Other cycles such as heating-cooling and wetting- drying creates similar stresses in stone. During certain synoptic conditions, building orientation has a great influence on climatic extremes of different facades. The use of sensors and data loggers has opened up the potential for in-depth investigations of general climatic monitoring of the exterior of buildings and effect of cyclic changes in temperature and moisture on stone. The chapter describes the study conducted to evaluate the frequency of heating-cooling, wetting-drying, and freeze-thaw cycles on the four cardinal faces of the tower of Lichfield Cathedral, Staffordshire, UK by using temperature and humidity sensors located on them.. It focuses on the assessment of the influence of orientation of building on the frequency of climatic cycles. The west and south faces have the highest frequency, whereas the north and east have the lowest values, with the north having the least. These could be loosely termed the “maritime” and “continental” faces, respectively. In a parallel study of 30 sandstone churches in the West Midlands, the occurrences of 18 forms of weathering were recorded. Granular disintegration, spalling, multiple flaking, total case hardened stone, and total autotrophic stone were found to be the greatest on the north; and relief weathering and total blackened stone were the greatest on south and west aspects.

Publisher Summary Coal derived particulates in the UK urban atmosphere have been significantly reduced because of reductions in domestic usage, legislation, and changes in fuel use. Majority of particulate in the urban atmosphere originate from vehicle exhausts because of increase in road usage and an expansion in the use of diesel engines. Particulate matter, resulting from coal combustion, has been recorded as being present in black patinas on some historic stone buildings and monuments, and it has been associated with accelerated weathering of stone surfaces as a result of enhanced gypsum formation. Some recent researches show the role of diesel particulates as a potential catalyst for the promotion of sulfation. This chapter describes the comparative study conducted to study the effects of coal and diesel particulates on the weathering of stones by using the technique of microcatchments under ambient atmospheric conditions. Slabs of Hollington sandstone and Portland limestone were artificially loaded with coal and diesel particulates, both separately and in various combinations. These slabs were then exposed to atmospheric conditions utilizing the microcatchment technique. All the chemical changes occurring as a result of the treatments were determined by comparison with an untreated stone control. The chapter provides tables and graphs to illustrate the results of analyses. It was found that diesel coated Portland limestone samples showed a significant reduction in both the rate of weathering loss and the volume of precipitation run-off when, compared to untreated samples. The samples treated with a combination of both particulate types demonstrated a highly significant increase in the volume of precipitation run-off from the sandstone microcatchments.

Regression analysis of data from 222 extracapsular cataract extractions was performed to determine if the accuracy of IOL prediction in cataract surgery can be improved. Polynomial and piecewise regression of large, medium, and short eyes were used to calculate new formulas for IOL prediction. The Taylor series representation of the theoretical lens power formula was calculated to determine what combination of the variables for IOL power prediction are reasonable to consider in constructing a polynomial regression model. The formulas calculated from the data in this study were compared with other published methods of IOL calculation. In this study, the difference between the postoperative refraction error and emmetropia was independent of the formula used. The exception was the modified Binkhorst formula, which caused greater error. Inclusion of higher order terms in the regression formula or piecewise regression did not reduce the postoperative refractive error.

As an interdisciplinary device, oral history is applicable to many uses. For biographers in particular, it holds great potential as a technique for transcending the problems of documenting contemporary lives. Oral history is not a new phenomenon; in fact, it is part of an ancient and venerable biographical tradition. A selective review of some recent biographical literature suggests that oral history is being re-discovered today, and this is portentous for the future of biography.

The most common indications for treatment of patients with pseudotumor cerebri are the presence of severe intractable headaches and evidence of optic neuropathy. The role of the ophthalmologist in following patients with pseudotumor cerebri has been to document optic nerve dysfunction in terms of visual field abnormalities or loss of visual acuity. Macular changes have been described in association with papilledema. A case of pseudotumor cerebri and associated macular disease is reviewed to call attention to the need for the ophthalmologist to differentiate between visual loss secondary to optic neuropathy from that of macular disease. The case illustrates how quickly macular disease can develop. The management of patients with pseudotumor cerebri is discussed. RETINA 9:115-117, 1989

Of 89 patients receiving nightly subcutaneous deferoxamine for transfusion-dependent thalassemia major or Diamond-Blackfan anemia, 13 presented with visual loss or deafness of acute onset or both. Detailed ophthalmologic, audiologic, and evoked-potential studies uncovered abnormalities caused by neurotoxicity in 27 more. Four patients with visual loss had optic neuropathy, with a marked decrease in acuity, loss of color vision, and delayed visual evoked potentials. Five asymptomatic patients had changes in the pigment of the retinal epithelium. The hearing loss was characterized by a high-frequency sensorineural deficit, which necessitated hearing aids in six patients. When deferoxamine was stopped, recovery of vision was complete in 2 patients and partial in 2, and in 22 patients with abnormal audiograms, reversal of the hearing deficit was complete in 4 and partial in 1. An analysis of the clinical data showed that members of the affected group were younger, had lower serum ferritin values, and were self-administering higher doses of deferoxamine per kilogram of body weight. Significantly lower doses of deferoxamine were being taken by patients without abnormalities than by those with visual symptoms, abnormal audiograms, or prolonged evoked potentials (P less than 0.001, less than 0.006, and less than 0.04, respectively). The data implicate high-dose deferoxamine as a central factor in the pathogenesis of the neurotoxicity. We strongly recommend careful regulation of the deferoxamine dosage and serial audiovisual monitoring in all patients receiving the drug.

This document is a guideline for the development of a detailed evaluation plant for a MIUS facility which was planned for demonstration at St. Charles, Maryland. The generic types of technical, institutional, and economic issues are discussed. General performance measures for the total system and each subsystem are indicated. The classes of data that will be required and the types of data analyses to be employed are outlined.

A method of basic combined cholecystangiography is described which has advantage over other methods so far used, especially in economy of time and expense. The technique is convenient to personnel and patient alike and is quite open to continuation and special techniques as required, depending on the appearances of the preliminary films.