Icing and De-Icing of a Propeller with Internal Electric Blade Heaters

An investigation has been made in the NACA Cleveland icing research tunnel to determine the de-icing effectiveness of an experimental configuration of an Internal electric propeller-blade heater. Two atmospheric Icing conditions and two propeller operating conditions were Investigated, In experiments with unheated blades and with heat applied to the blades both continuously and cyclically. Data are presented to show the effect of propeller speed., ambient air temperature and liquid-water concentration, and the duration of the heat-on and cycle times on the power requirements and de-Icing performance of the blade heaters. The extent of ice-covered area on the blades for various icing ax4 operating conditions has been determined. The largest iced area was obtained at the higher ambient-air temperatures and at low propeller speed. The ohord.wise extent of Icing In practically every case was greater than that covered by blade heaters. Adequate de-icing in the heated area with continuous application of heat was obtained with the power available but a maximum power, input of 1250 watts per blade was insufficient for cyclic de-Icing for the range of conditions investigated. Blade-surface temperature rates of rise of 0.2 to 0.7 F per second were obtained and the minimum cooling period for cyclic de-icing was found to be approximately 2-1/2 times the heating period

The Distribution, Transport and Age Structure of Drums (Family Sciaenidae) Spawned in the Winter and Early Spring in the Continental Shelf Waters Off West Louisiana (Transit Time, Length-Frequency, Morphology, Density).

Aspects of the early life history of 6 species of sciaenids that spawned in west Louisiana shelf waters from December 1981 to April 1982 were studied. This research documented the distribution of larvae and tested a transport hypothesis that detailed advective processes which affected their distribution and, ultimately, recruitment into estuaries in southwest Louisiana, and provided information on larva age and growth. Ranked in order of abundance the six sciaenid species collected were: sand seatrout (Cynoscion arenarius); Atlantic croaker (Micropogonias undulatus); spot (Leiostomus xanthurus); black drum (Pogonias cromis); southern kingfish (Menticirrhus americanus; and banded drum (Larimus fasciatus). Atlantic croaker, spot and black drum were most abundant early in December to February while sand seatrout were most abundant in April. Larva density was highest in April and high densities were associated with a freshet of water on the shelf that probably issued from the Atchafalaya River east of the study area. Most larvae were captured in water less than 40 m deep even though some were present to the shelf break (115m). Spawning by these sciaenid species took place over the continental shelf and the larvae were transported into near-shore coastal waters. Transport rates and larva transit times have been roughly quantified. The density-distribution of sciaenid larvae and a suite of environmental variables collected concurrently were analyzed statistically by using canonical correlation analysis. Among the environmental variables examined were micronutrients (nitrate, silicate, phosphate etc.), temperature, salinity, chlorophyll a and zooplankton biomass. In general, sciaenid larvae were most highly correlated with increased zooplankton biomass, but several broad associations between larva density-distribution and environmental variables were identified. The age and growth rate of the larval Atlantic croaker were estimated from growth increments in saccular otoliths. Examination of the data suggested that the growth increments were daily and were used to generate the linear growth equation L(,(t)) = 0.189 (t) + 0.634 mm TL which described larvae growth from an estimated 40 to 80 days old. Two distinct morphological types (morphs) of larval sand seatrout were identified. The morphs were distinguished by 3 pigment differences and nearly 100% separation was possible. The two morphs also exhibited differences in body depth and larva growth rates; differences were tested statistically with analysis of covariance. The morphs were separated in horizontal space and little overlap occurred in their density-distribution

The Phases and Faces of the Duke Lacrosse Controversy: A Conversation James E. Coleman, Jr.

This panel took place at the 2008 Annual Meeting of the Southeastern Association of Law Schools ( SEALS ) in July 2008 in West Palm Beach, Florid

Iron mineralogy of a Hawaiian palagonitic soil with Mars-like spectral and magnetic properties

Visible and near-IR spectral data for some palagonitic soils from Mauna Kea, Hawaii, are similar to corresponding spectral data for Mars. It is important to understand the composition, distribution, and mineralogy of the ferric-bearing phases for the best spectral analogues because the correspondence in spectral properties implies that the nature of their ferric-bearing phases may be similar to those on Mars. In order to constrain interpretations of the Martian data, a variety of palagonitic soils should be studied in order to establish to what extent differences in their spectral data correspond to differences in the mineralogy of their ferric-bearing phases. Spectral (350-2100 nm), Mossbauer, magnetic, and some compositional data for one of a suite of Hawaiian palagonitic soils are presented. The soil (HWMK1) was collected below the biologically active zone from the sides of a gully cut at 9000 ft elevation on Mauna Kea. The soil was wet sieved with freon into seven size fractions less than 1 mm

Ecological and physiological studies of the effect of sulfate pulp mill wastes on oysters in the York River, Virginia

This study of the York River and issues impacting the oyster fishery provides historical information on the river\u27s physical and chemical conditions (temperature, salinity, dissolved oxygen, turbidity, currents, etc.) effluent observations, history and data of the oyster fishery, oyster condition, biological and pathological work and experimental studies. The project studies were responsible for the establishment of a fisheries laboratory in Yorktown, Va. p. 59 - Funds for the York River investigations were made available in 1935 by a special allotment from the Public Works Administration. Continuation of the project was made possible by regular allotments by the Bureau of Fisheries and appropriations from the Commonwealth of Virginia through its Commission of Fisheries. In October 1935 a laboratory was established at Yorktown, Va., where a satisfactory supply of sea water was available for physiological studies\u27 on oysters. A boat suitable for the field observations was supplied by the Virginia Commission of Fisheries. Studies of the chemical nature of the pulp-mill effluents were carried on from July 1938 to July 1940 at laboratories made available by the College of William and Mary

Reproductive Competency and Mitochondrial Variation in Aged Syrian Hamster Oocytes

The hamster is a useful model of human reproductive biology because its oocytes are similar to those in humans in terms of size and structural stability. In the present study we evaluated fecundity rate, ovarian follicular numbers, ova production, mitochondrial number, structure and function, and cytoplasmic lamellae (CL) in young (2–4 months) and old (12–18 months) Syrian hamsters (Mesocricetus auratus). Young hamsters had higher fertilisation rates and larger litters than old hamsters (100 vs 50% and 9.3 +/- 0.6 vs 5.5 +/- 0.6, respectively). Ovarian tissue from superovulated animals showed a 46% decrease in preantral follicles in old versus young hamsters. There was a 39% reduction in MII oocyte number in old versus young hamsters. Young ova had no collapsed CL, whereas old ova were replete with areas of collapsed, non-luminal CL. Eighty-nine per cent of young ova were expanded against the zona pellucida with a clear indentation at the polar body, compared with 58.64% for old ova; the remaining old ova had increased perivitelline space with no polar body indentation. Higher reactive oxygen species levels and lower mitochondrial membrane potentials were seen in ova from old versus young hamsters. A significant decrease in mitochondrial number (36%) and lower frequency of clear mitochondria (31%) were observed in MII oocytes from old versus young hamster. In conclusion, the results of the present study support the theory of oocyte depletion during mammalian aging, and suggest that morphological changes of mitochondria and CL in oocytes may be contributing factors in the age-related decline in fertility rates

Consistent improvement with eculizumab across muscle groups in myasthenia gravis

Objective: To assess whether eculizumab, a terminal complement inhibitor, improves patient- and physician-reported outcomes (evaluated using the myasthenia gravis activities of daily living profile and the quantitative myasthenia gravis scale, respectively) in patients with refractory anti-acetylcholine receptor antibody-positive generalized myasthenia gravis across four domains, representing ocular, bulbar, respiratory, and limb/gross motor muscle groups. Methods: Patients with refractory anti-acetylcholine receptor antibody-positive generalized myasthenia gravis were randomized 1:1 to receive either placebo or eculizumab during the REGAIN study (NCT01997229). Patients who completed REGAIN were eligible to continue into the open-label extension trial (NCT02301624) for up to 4 years. The four domain scores of each of the myasthenia gravis activities of daily living profile and the quantitative myasthenia gravis scale recorded throughout REGAIN and through 130 weeks of the open-label extension were analyzed. Results: Of the 125 patients who participated in REGAIN, 117 enrolled in the open-label extension; 61 had received placebo and 56 had received eculizumab during REGAIN. Patients experienced rapid improvements in total scores and all four domain scores of both the myasthenia gravis activities of daily living profile and the quantitative myasthenia gravis scale with eculizumab treatment. These improvements were sustained through 130 weeks of the open-label extension. Interpretation: Eculizumab treatment elicits rapid and sustained improvements in muscle strength across ocular, bulbar, respiratory, and limb/gross motor muscle groups and in associated daily activities in patients with refractory anti-acetylcholine receptor antibody-positive generalized myasthenia gravis

Phases and Faces of the Duke Lacrosse Controversy: A Conversation

This panel took place at the 2008 Annual Meeting of the Southeastern Association of Law Schools (SEALS) in July 2008 in West Palm Beach, Florida. The transcript has been edited for grammar, punctuation and writing style, as well as for limited content changes

Recent Applications of Space Weather Research to NASA Space Missions

Marshall Space Flight Center s Space Environments Team is committed to applying the latest research in space weather to NASA programs. We analyze data from an extensive set of space weather satellites in order to define the space environments for some of NASA s highest profile programs. Our goal is to ensure that spacecraft are designed to be successful in all environments encountered during their missions. We also collaborate with universities, industry, and other federal agencies to provide analysis of anomalies and operational impacts to current missions. This presentation is a summary of some of our most recent applications of space weather data, including the definition of the space environments for the initial phases of the Space Launch System (SLS), acquisition of International Space Station (ISS) frame potential variations during geomagnetic storms, and Nascap-2K charging analyses