Advanced flight control system study

A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts

Computer recommendations for an automatic approach and landing system for V/STOL aircraft. Volume 2 - Equations

Automatic approach and landing system for V/STOL aircraf

Super-Kamiokande 0.07 eV Neutrinos in Cosmology: Hot Dark Matter and the Highest Energy Cosmic Rays

Relic neutrinos with mass in the range indicated by Super-Kamiokande results if neutrino masses are hierarchial (about 0.07 eV) are many times deemed too light to be cosmologically relevant. Here we remark that these neutrinos may significantly contribute to the dark matter of the Universe (with a large lepton asymmetry $L$) and that their existence might be revealed by the spectrum of ultra high energy cosmic rays (maybe even in the absence of a large $L$).Comment: Talk given at the ``4th International Symposium on Sources and Detection of Dark Matter in the Universe", February 23-25, 2000, Marina del Rey, CA (to appear in its proceedings) and at the ``Cosmic Genesis and Fundamental Physics" workshop, October 28-30, 1999, Sonoma State University, Santa Rosa, CA. (8 p. 1 fig.

X=Y–ZH compounds as potential 1,3-dipoles. Part 64: Synthesis of highly substituted conformationally restricted and spiro nitropyrrolidines via Ag(I) catalysed azomethine ylide cycloadditions

1,3-Dipolar reactions of imines of both acyclic and cyclic α-amino esters with a range of nitroolefins using a combination of AgOAc or Ag2O with NEt3 are described. In most cases the reactions were highly regio- and stereospecific and endo-cycloadducts were obtained in good yield. However, in a few cases the initially formed cycloadducts underwent base catalysed epimerisation. The stereochemistry of the cycloadducts was assigned from NOE data and established unequivocally in several cases by X-ray crystallography

Sinteza i anthelmintičko djelovanje novih 2-supstituiranih-4,5-difenil imidazola

A series of 2-substituted-4,5-diphenyl imidazoles 1a-j were synthesized by refluxing benzil with different substituted aldehydes in the presence of ammonium acetate and glacial acetic acid. Structures of the synthesized compounds were confirmed on the basis of IR, 1H NMR and mass spectral data. Compounds 1a-j were screened for anthelmintic activity. Test results revealed that compounds showed paralysis time of 0.24 to 1.54 s and death time of 0.39 to 4.40 s while the standard drugs albendazole and piperazine citrate showed paralysis time of 0.54 and 0.58 s and death time of 2.16 and 2.47 s, respectively, at the same concentration of 1 % (m/V). Five compounds, 2-[2-hydroxyphenyl]-4,5-diphenyl imidazole (1b), 2-[3-methoxyphenyl]-4,5-diphenyl imidazole (1c), 2-[2-phenylethenyl]-4,5-diphenyl imidazole (1e), 2-[4-fluorophenyl]-4,5-diphenyl imidazole (1g) and 2-[3-nitrophenyl]-4,5-diphenyl imidazole (1h) showed significant anthelmintic activity compared to the standard drugs.Refluksiranjem benzila s različitim supstituiranim aldehidima u prisutnosti amonijeva acetata i ledene octene kiseline sintetizirana je serija 2-supstituiranih-4,5-difenil imidazola (1a-j). Strukture sintetiziranih spojeva potvrđene su IR, 1H NMR i masenom spektroskopijom. U testovima na anthelmintičko djelovanje određeno je vrijeme paralize 0,24 do 1,54 min i vrijeme smrti 0,39 do 4,40 min, dok standarni lijekovi albendazol i piperazin citrat imaju vrijeme paralize 0,54 i 0,58 min, a vrijeme smrti 2,16, odnosno 2,47 min pri istim koncentracijama (1 % m/V). Pet spojeva, 2-[2-hidroksifenil]-4,5-difenil imidazol (1b), 2-[3-metoksifenil]-4,5-difenil imidazol (1c), 2-[2-feniletenil]-4,5-difenil imidazol (1e), 2-[4-fluorofenil]-4,5-difenil imidazol (1g) i 2-[3-nitrofenil]-4,5-difenil imidazol (1h) pokazuju značajno anthelmintičko djelovanje u odnosnu na standardne lijekove

Set Theory and its Place in the Foundations of Mathematics:a new look at an old question

This paper reviews the claims of several main-stream candidates to be the foundations of mathematics, including set theory. The review concludes that at this level of mathematical knowledge it would be very unreasonable to settle with any one of these foundations and that the only reasonable choice is a pluralist one

Mapping localized surface plasmons within silver nanocubes using cathodoluminescence hyperspectral imaging

Localized surface plasmons within silver nanocubes less than 50 nm in size are investigated using high resolution cathodoluminescence hyperspectral imaging. Multivariate statistical analysis of the multidimensional luminescence dataset allows both the identification of distinct spectral features in the emission and the mapping of their spatial distribution. These results show a 490 nm peak emitted from the cube faces, with shorter wavelength luminescence coming from the vertices and edges; this provides direct experimental confirmation of theoretical predictions

Tetraspanin (TSP-17) Protects Dopaminergic Neurons against 6-OHDA-Induced Neurodegeneration in <i>C. elegans</i>

Parkinson's disease (PD), the second most prevalent neurodegenerative disease after Alzheimer's disease, is linked to the gradual loss of dopaminergic neurons in the substantia nigra. Disease loci causing hereditary forms of PD are known, but most cases are attributable to a combination of genetic and environmental risk factors. Increased incidence of PD is associated with rural living and pesticide exposure, and dopaminergic neurodegeneration can be triggered by neurotoxins such as 6-hydroxydopamine (6-OHDA). In C. elegans, this drug is taken up by the presynaptic dopamine reuptake transporter (DAT-1) and causes selective death of the eight dopaminergic neurons of the adult hermaphrodite. Using a forward genetic approach to find genes that protect against 6-OHDA-mediated neurodegeneration, we identified tsp-17, which encodes a member of the tetraspanin family of membrane proteins. We show that TSP-17 is expressed in dopaminergic neurons and provide genetic, pharmacological and biochemical evidence that it inhibits DAT-1, thus leading to increased 6-OHDA uptake in tsp-17 loss-of-function mutants. TSP-17 also protects against toxicity conferred by excessive intracellular dopamine. We provide genetic and biochemical evidence that TSP-17 acts partly via the DOP-2 dopamine receptor to negatively regulate DAT-1. tsp-17 mutants also have subtle behavioral phenotypes, some of which are conferred by aberrant dopamine signaling. Incubating mutant worms in liquid medium leads to swimming-induced paralysis. In the L1 larval stage, this phenotype is linked to lethality and cannot be rescued by a dop-3 null mutant. In contrast, mild paralysis occurring in the L4 larval stage is suppressed by dop-3, suggesting defects in dopaminergic signaling. In summary, we show that TSP-17 protects against neurodegeneration and has a role in modulating behaviors linked to dopamine signaling

Metoclopramide protection of diazinon-induced toxicosis in chickens

The efficacy of metoclopramide for preventing organophosphate insecticide-induced (diazinon) toxicosis was evaluated in 7~14 days old chicks. Injection of metoclopramide at 25 mg/kg, s.c. 15 min before diazinon increased the oral 24 h median lethal dose of the insecticide in the chicks by 80%. Metoclopramide alone inhibited the in vitro and in vivo plasma and whole brain cholinesterase activities of the chicks. Metoclopramide pretreatment at 100 mg/kg, s.c. reduced the extent of cholinesterase inhibition that was caused by diazinon (10 mg/kg, p.o.) in the plasma and whole brain by 24% and 7%, respectively. Diazinon at 10 mg/kg, p.o. produced signs of cholinergic toxicosis in the chicks, and these signs included salivation, lacrimation, gasping and convulsions within 2 h, and the 2-h and 24-h lethalities were 88 and 100%, respectively. Metoclopramide at the dose rates of 12.5, 25, 50, 100 and 200 mg/kg, s.c. given 15 min before diazinon (10 mg/kg, p.o.) variably decreased the occurrence of toxic manifestations in the chicks. The highest dose of metoclopramide (200 mg/kg, s.c.) reduced the 2-h and 24-h lethality of diazinon to 75% each and it reduced the overall toxicity score of diazinon by 32%. The data suggest that metoclopramide pretreatment only partially protected chicks against the acute toxicity of diazinon