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Hope For the Hopi: Finding Prosperity On the Rez

This paper focuses on my findings on the Hopi Basket Dance—a dance that is part of the Hopi Ceremonial tradition—and changes in their ceremonial tradition and culture as a result of external and internal forces

Impact of a sight-saver clinic on the prevalence of blindness in northern KwaZulu

The prevalence of blindness in the Ingwavuma district of northern Kwazulu was 1% (95% confidence interval 0,75 - 1,25) in 1990, and the prevalence of blindness due solely to age-related cataract was 0,39% (95% Cl 0,24 - 0,54). Eight sight-saver clinics were held between 1990 and 1993. Nine hundred and thirteen patients were seen and 113 cataract extractions performed at a cost of R62 000. The prevalence of blindness due solely to agerelated cataract was reduced by 25% to 0,29% (95% Cl 0,17 - 0,41). The overall prevalence of blindness was reduced by 4% to 0,96% (95% Cl 0,72 - 1,20). The. provision of aphakic spectacles to aphakic patients whose spectacles have either been lost or broken would effect a further 11 % reduction to 0,85% (95% Cl 0,63 - 1,07). The establishment of a permanent sight-saver clinic staffed by an ophthalmic medical assistant who is working full-time in this capacity would facilitate an improvement in the delivery of eye care in the area

NATURE OF LYMPHOCYTE-TUMOR INTERACTION : A GENERAL METHOD FOR CELLULAR IMMUNOABSORPTION

The binding of sensitized lymphocytes to tumor cells that leads to tumor cell lysis in vitro has been investigated using poly-L-lysine-fixed tumor cell monolayers and lymphocytes obtained from the anatomical site of tumor allograft rejection. The results show that magnesium is an important prerequisite for this interaction and that the extent of lymphocyte-tumor cell binding depends upon temperature as well as pH. Binding can occur in the absence of serum, although serum factors are necessary for the completion of the cytolytic process. The poly-L-lysine technique is applicable to the formation of confluent monolayers with virtually any normal or neoplastic cell type, including those that are otherwise nonadherent to surfaces. Cells immobilized by this technique can be used for the specific immunoabsorption and subsequent recovery of effector lymphocytes sensitized against transplantation or tumor cell antigens

Results of laser treatment for sub-retinal neovascular membranes

A retrospective study was carried out to determine the results of laser treatment for choroidal neovascular membranes in age-related macular degeneration in 92 patients in whom fluorescein angiography was performed for this condition over a 7-year period. Twenty-nine of these patients, treated with the argon laser, were followed up regularly for 15 months. The treatment comprised overlapping laser spots of 200 J.Lm and an average power of 390 mW. The results of this study demonstrated that: (i) the majority of membranes were closer ·than 500 J.Lm from the foveola; (ii) the second eye involvement rate in the same patient was 15,79% over 15 months; and (iii) a 37,5% significant visual' loss or 41% two lines or greater visual loss was seen after 15 months, which compares favourably with results of laser treatment reported by other institutions

Prevalence and incidence' of blindness due to agerelated cataract in the rural areas of South Africa

Objectives. The Bureau for the Prevention of Blindness is responsible for the provision of cataract surgery to the rural indigent population of South Africa. It is important for the Bureau to know both the prevalence and the incidence of cataract blindness in the population.Design, setting and subjects. Blindness prevalence surveys were conducted in Kwazulu in 1.990 and 1993.Outcome measures and results. The prevalence of cataract blindness was 0,59% (95% confidence interval 0,21) in 1990 and 1993. The prevalence of aphakia was 0,1% in 1990 and 0,2% in 1993, demonstrating a probable increase in the delivery of cataract surgical services, although this had not produced a demonstrable fall in the prevalence of cataract blindness. The calculated annual incidence of cataract blindness was 0,14%.Conclusion. Among a rural population of approximately 19 million South Africans, there is a backlog of 113 000 unoperated cataract-blind people and an incidence of 27 000 new cataract blind per year. The implications of this backlog for cataract blindness in our rural areas are discussed

Ophthalmoscopy versus non-mydriatic fundus photography in the detection of diabetic retinopathy in black patients

The contribution of non-mydriatic fundus photography in the detection of diabetic retinopathy before and after dilatation of the pupils in black diabetics was investigated and compared with direct ophthalmoscopy. Eighty-six patients were examined and good-quality photographs were obtained for 54,7% of eyes before and 86,6% of eyes after dilatation. Photographically documented retinopathy was detected by ophthalmoscopy in only 64,7% of eyes. The two methods were concordant for the presence of retinopathy in 62,2% of eyes before and 56,9% of eyes after dilatation. Photography through dilated pupils also i.mproved the rate of detection of diabetic retinopathy from 24% to 30%. The 45° non-mydriatic fundus camera was found to be a valuable adjunct in the detection of diabetic retinopathy in a busy diabetic clinic

COST COMPARISONS OF CAPITOL INVESTMENT IN VARIOUS NUCLEAR POWER PLANTS FOR CENTRAL STATION APPLICATION

The capital costs for a number of power reactors are compared after escalation to equivalent construction dates. It is shown that the most important factor affecting nuclear power plant capital costs is the net capacity of the plant. Steam conditions are shown to have a relatively minor effect on capital costs. (auth