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We present a time‐of‐flight mass spectrometer design for the measurement of ions in the ~30 keV to 10 MeV range for protons (up to ~40 MeV and ~150 MeV for He and heavy ions, respectively) and ~30 keV to 1 MeV range for electrons, covering half of the sky with 80 apertures. The instrument, known as the “Mushroom,” owing to its shape, solves the field of view problem for magnetospheric and heliospheric missions that employ three‐axis stabilized spacecraft, yet still require extended angular coverage; the Mushroom is also compatible with a spinning spacecraft. The most important new feature of the Mushroom is the method through which uncomplicated electrostatic optics and clean position sensing combine to permit many apertures to fit into a compact, low‐mass sensor head (or wedge), several of which (ideally eight) compose a full instrument. Most of the sensor head's volume is an empty, equipotential region, resulting in the modest 250 g mass of each 10‐aperture wedge. The Mushroom is capable of separating ion species across most of its energy range and angular field of view. For example, separation of the neighboring 3He and 4He isotopes is excellent; the full width at half maximum mass resolution has been measured to be 0.24 amu to 0.32 amu, respectively. Converting this to a Gaussian width σmin mass m, this represents a σm/mmass resolution better than 0.04. This separation is highly desirable for the flight program for which the first Mushroom was built, the Solar Probe Plus mission. More generally, we estimate the mass resolution to be σm/m≈ 0.1, but this is energy, mass, and angularly dependent. We also discuss the solid‐state detector stack capability, which extends the energy range of protons and helium, with composition, to ~100 MeV. Anisotropy, pitch angle distributions, and large field of view are important for energetic ion and electron scienceThe “Mushroom” instrument has been developed by JHU/APL to provide needed large FOV and angular resolutionThe first Mushroom, EPI‐Lo, part of the ISʘIS investigation on Solar Probe Plus, has achieved excellent composition and spatial separation

Liposomes with various lipid composition and sizes, prepared by two different techniques were evaluated for their potential to deliver desferrioxamine to lungs as a treatment against oxidative lung damage. Multilamellar vesicles (MLV) and reverse evaporation vesicles were prepared out of a lipid mixture containing dipalmitoyl phosphatidylcholine, stearyl amine, cholesterol and vitamin E. The administration of desferrioxamine-encapsulated liposomes to rats by the intravenous route at a dose of 100 mg kg−1, significantly prolonged the presence of desferrioxamine in all the tested organs when compared with the administration of free desferrioxamine. The injection of reverse evaporation vesicles extruded through a 2 μm polycarbonate membrane exhibited a longer residence time of the desferrioxamine and of liposomal vitamin E in lungs compared with the other types of liposomes tested. The examination of liposome components in the bronchoalveolar lavage fluid (BALF) and the alveolar macrophages recovered from BALF revealed that about 7 × 10−3% of the administered desferrioxamine dose was recovered by this technique at 3 and 17 h after liposome administration. This high residual concentration in the alveolar space confirms the hypothesis that liposomes can be delivered to the lung tissue when encapsulated in alveolar macrophages.

Flame atomic absorption photometry (AA), and emission spectroscopy (ES) were compared to the molybdenum blue spectrophotometric method (SP) for analysis of silicon in atmospheric particulate matter and in NBS standard reference materials. All techniques gave systematically low values, the range being 9-30% low with respect to the NBS values. Employing lithium metaborate as the fusion medium, the AA method proved to be approximately equivalent to the SP procedure in precision and accuracy. The ES technique displayed relatively poor accuracy and precision. Lithium metaborate provided substantially better solublization of the more refractory NBS standards compared to sodium carbonate.

A comparison of ESCA with wet chemical and other analytical techniques has demonstrated agreement within about a factor of 2 for sulfate and carbon but gave much larger deviations for nitrate and ammonium in analysis of atmospheric particulate samples collected in California's South Coast Basin. Analyses for nitrate and ammonium were low by a factor of 5 to 10 relative to the wet chemical methods. Loss of volatile ammonium- and nitrate-containing materials under the high vacuum and localized X-ray beam-induced heating conditions of ESCA was the most reasonable explanation of the discrepancy. Detailed temperature programmed ESCA studies support this conclusion and suggest the significance of highly volatile nitrate (e.g. nitric acid) and ammonium compounds in the atmospheric particles.

We investigated a possible role for N-acetylcysteine (NAC), a well-known antioxidant and free radical scavenger, against oxidative lung damage as observed in the in vivo model of paraquatintoxicated rats. The administration of two ip doses of 50 mg/kg NAC to paraquat-intoxicated animals did not change the glutathione status of the lungs, as determined by the measurement of nonprotein sulfhydryl (NP-SH) groups. The administration of NAC did however suppress the paraquat-induced release of chemoattractants for neutrophils in the bronchoalveolar fluid when the lavage was carried out 12 hr after the administration of 30 mg/kg paraquat. Also, in the intoxicated NAC-treated animals, the infiltration of inflammatory cells was significantly reduced, as demonstrated by the examination of the cell composition of the bronchoalveolar lavage (BAL), 24 hr after paraquat. Phorbol myristate acetate-stimulated superoxide anion production from the AM isolated from the HAL of paraquat-intoxicated nontreated animals was lower than that of controls, whereas in the NAC-treated animals, it was close to that of the controls. The obtained results indicate that NAC has a protective effect against oxidative lung damage by delaying inflammation. It also prevents the paraquat-induced reduction of superoxide anion production by stimulated AM. In the present model, however, the NAC administration regimen did not affect the survival rate of paraquat-intoxicated rats.Copyright 1993, 1999 Academic Press

Data concerning 15 consecutive cases of single exposures of the skin or eyes during work to paraquat solutions are presented. Urine and serum were analysed for paraquat in all these cases at the laboratory of the Israel Poison Information Center. From these data it is apparent that a single exposure of healthy skin to paraquat solutions caused only local lesions. No systemic effect was detected in these patients.

L’eczéma de contact allergique est une dermatose inflammatoire récidivante dont la physiopathologie pourrait reposer sur la présence de lymphocytes T résidents mémoires (TRM) cutanés dans la peau précédemment exposée et sensibilisée. Ici nous souhaitions activer les TRMd’un allergène cutané donné, à différents stades de la maladie pour caractériser les réponses tissulaires précoces lors d’une élicitation.