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Feeding a vitamin E-deficient diet containing 5% menhaden oilto mice affordssignificant protectionagainstboth a chloroquine-sensitive and a chloroquine-resistant line of the malarial parasite. Nutritional manipulation may offer a new approach to the prob- lem of drug-resistant malaria, a rapidlyemergingglobal threat to public health. Am J Clin Nutr l989;50: 1237-9.

A review of the smart structures and avionics research and teaching program that started in 1979 at Virginia Tech is described. Current smart structures research include major efforts in the development of embedded and attached optical fiber and acoustic fiber sensors for cure monitoring, in-service lifetime structural testing, nondestructive evaluation, and impact and damage detection and analysis; of gradual material degradation; sensor signal multiplexing, processing and data handling to achieve near real-time distributed structural analysis; and the integration of embedded sensors, actuators and control electronics to achieve controlled structural response. Special campus facilities used for this work include an optical fiber fabrication facility, an autoclave for composite structure fabrication and curing, and laboratories for optical fiber sensor development, materials response and nondestructive evaluation, structural control testing and computer engineering.

Young female mice were fed torula-yeast-based diets deficient in vitamin E or selenium or supplemented with cod-liver oil to determine the effect of host antioxidant status on the therapeutic efficacy of the Chinese traditional antimalarial drug qinghaosu (QHS), a sesquiterpene endoperoxide. Vitamin E deficiency enhanced the antimalarial action of QHS against Plasmodium yoelii, both in terms of decreased parasitemia and improved survival but Se deficiency did not. A vitamin E-deficient diet containing 5% cod-liver oil had such strong antimalarial activity in itself that no additional therapeutic benefit of QHS could be demonstrated. Hematocrit values in parasitized mice treated with QHS or fed the cod-liver-oil-supplemented, vitamin E-deficient diet were normal. Nutritional manipulation of host antioxidant status may provide a promising prophylactic and/or therapeutic tool for the control of malaria.

The use of a photodetector array to process the full far-field output of a modal domain fiber optic sensor is reported. The array is linked to a laboratory computer, which reduces the data in real time and measures the transfer of power between the two lobes of the far-field output of a dual-moded fiber. The power transfer is generated by imparting a longitudinal strain to the fiber. The ratio of powers in the two lobes can be used to determine the magnitude of strain.

The interconnection of fiber-optic transmission lines to rotating devices requires the development of a continuously rotatable, low-loss, bidirectional optical rotary joint. This paper discusses the physical properties and optical performance of a rotary joint that will accommodate a single optical fiber with graded index profile and 50-micrometer core size. The device was developed for the Naval Research Laboratory by ITT, Electro-Optical Products Division to mechanically decouple optical fibers exiting from a rotating cable-winch system. For this specific application, a rotary joint can be used at each end of the winch axle, thereby allowing access to a total of two optical fibers. Since many uses of a rotary joint require the transfer of both electrical and optical power, the optical joint was incorporated into the housing of a 7-band, 10 Ampere (each) electrical slip-ring assembly provided by Electro-Tec Corporation. mhe nrecision bearings in the slip-ring housing provided a mechanical runout of less than .013 mm and an angular variation no greater than 0.2 degrees. Beam expansion and collimation techniques were used to reduce the dependence of optical loss on longitudinal and transverse offset at the rotational interface. Two quarter-pitch SELFOC rod lenses of 1 mm diameter, obtained from NSG, America, were used to achieve the beam expansion and collimation. The optical leads to the rotary joint were in the form of an unterminated single-fiber cable of approximately one meter length having a KEVLAR aramid sheath and a polyurethane overjacket. The maximum optical insertion loss at any rotational position was 1.3 dB at 830 nm and less than 1.7 dB at 1300 nm. The variation of insertion loss caused by device rotation was less than 0.25 dB at both wavelengths. At the conclusion of an endurance test of 310,000 revolutions at a 30 RPM rate, no degradation in performance could be observed.

Naegleria fowleri produced fatal meningoencephalitis in mice following intravenous (i.v.) inoculation. Amebae were present in the peripheral circulation for 120 minutes after i.v. inoculation with a dose of 10(7) trophozoites per mouse. Amebae were cultured from and observed in brain (days 1-21), lung (days 1-12), and liver and kidney (days 1-5). Infected mice exhibited weight loss, leukocytosis, reduced lymphocyte/neutrophil ratio, neurologic symptoms, and mortality. Histologically, the disease was characterized by an acute, hemorrhagic, necrotizing meningoencephalitis. Although amebae were detected in tissues other than brain, pathologic involvement of these tissues was minimal.

Information is not available on the extent of population shifts, if any, in synthetic cultivars of smooth bromegrass resulting from seed multiplication in diverse environments, methods of breeder seed synthesis, or seed maturity at harvest. Objectives of our research were to determine effects of two methods of breeder seed syntheses, three diverse locations of seed production, and three seed maturities at harvest upon the population stability of ‘Saratoga’ smooth bromegrass (Leyss.). Polycross seed was produced in vegetatively established nurseries at Shafter and Tehachapi, Calif., and Prosser, Wash. At each location two breeder seed lots were synthesized using 1) equal parts of pure live seed from each of the 5 parental clones, or 2) portions equivalent to relative seed yields. These lots, plus similar blends produced at Ithaca, N.Y., were used to plant four isolated increase blocks at the three western locations to produce second generation seed harvested at early, optimum, or late maturity. The second generation seed lots, including the original breeder seed blends, were evaluated in a space-planted nursery at Prosser in 1978 and 1979. Four plant characteristics were measured: heading date, anthesis date, plant height, and rhizome spread after 2 years. Plants from second generation seed produced at Shafter tended to be taller with less rhizome spread than those from Prosser or Tehachapi. Otherwise there were no consistent trends to indicate that methods of synthesizing breeder seed or location of production affected the population characteristics. Maturity of seed at harvest had no effect on plant characteristics. Based on these results we concluded that even though the parental clones were significantly different, the Saratoga bromegrass synthetic, and perhaps other bromegrass synthetics, would be very stable under differing management and environmental conditions.