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

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

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

Clinical and microbiological characteristics of fungal keratitis in the United States, 20012007: A multicenter study

Objective: To study the epidemiology, clinical observations, and microbiologic characteristics of fungal keratitis at tertiary eye care centers in the United States. Design: Retrospective multicenter case series. Participants: Fungal keratitis cases presenting to participating tertiary eye care centers. Methods: Charts were reviewed for all fungal keratitis cases confirmed by culture, histology, or confocal microscopy between January 1, 2001, and December 31, 2007, at 11 tertiary clinical sites in the United States. Main Outcome Measures: Frequency of potential predisposing factors and associations between these factors and fungal species. Results: A total of 733 cases of fungal keratitis were identified. Most cases were confirmed by culture from corneal scraping (n = 693) or biopsies (n = 19); 16 cases were diagnosed by microscopic examination of corneal scraping alone; and 5 cases were diagnosed by confocal microscopy alone. Some 268 of 733 cases (37%) were associated with refractive contact lens wear, 180 of 733 cases (25%) were associated with ocular trauma, and 209 of 733 cases (29%) were associated with ocular surface disease. No predisposing factor was identified in 76 cases (10%). Filamentous fungi were identified in 141 of 180 ocular trauma cases (78%) and in 231 of 268 refractive contact lens-associated cases (86%). Yeast was the causative organism in 111 of 209 cases (53%) associated with ocular surface disease. Yeast accounted for few cases of fungal keratitis associated with refractive contact-lens wear (20 cases), therapeutic contact-lens wear (11 cases), or ocular trauma (21 cases). Surgical intervention was undertaken in 26% of cases and was most frequently performed for fungal keratitis associated with ocular surface disease (44%). Surgical intervention was more likely in cases associated with filamentous fungi (P = 0.03). Among contact lens wearers, delay in diagnosis of 2 or more weeks increased the likelihood of surgery (age-adjusted odds ratio = 2.2; 95% confidence interval, 1.24.2). Conclusions: Trauma, contact lens wear, and ocular surface disease predispose patients to developing fungal keratitis. Filamentous fungi are most frequently the causative organism for fungal keratitis associated with trauma or contact lens wear, whereas yeast is most frequently the causative organism in patients with ocular surface disease. Delay in diagnosis increases the likelihood of surgical intervention for contact lens-associated fungal keratitis. Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references

ELECTRICAL INSULATION CHARACTERISTICS OF HELIUM GAS AT HIGH PRESSURES AND TEMPERATURES

ABS>Published information is not available for accurate prediction of the electrical insulating characteristics of helium at high pressures and temperatures. In general the breakdown voltage increases as the gas pressure is increased and decreases as the gas temperature is increased. The relatively low breackdown voltage of helium accents the importance of additional investigation in this field. (auth

THORS: a high-temperature sodium test facility rated at 2. 0 MW. [LMFBR]

The Thermal--Hydraulic Out-of-Reactor Safety (THORS) facility at Oak Ridge Naitonal Laboratory (ORNL) is a high-temperature sodium test facility operated for the United States Breeder Reactor Safety Program. The facility is primarily used for testing large simulated Liquid-Metal Fast Breeder Reactor (LMFBR) fuel subassemblies. The facility has recently been upgraded to provide a 2.0-MW test bundle power input and heat removal capability. A new test section, which will be capable of operating at 980/sup 0/C and which will accommodate a 217-pin bundle, has also been added. A 61-pin bundle is currently under test in the facility. A description of the test facility is presented, along with a brief summary of the 8-year operating history of this safety-related test facility