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J. Hou, European Patent Office Munich,
G. Kramer, Chair of Communications Engineering, Technische Universität München,
M. Bloch, School of Electrical and Computer Engineering, Georgia Institute of Technology
Galactic background radiation has been observed in the 78-111 eV Be band using 5000 Å beryllium filters in front of a thin-window proportional counter collimated to a 15° full width at half maximum field of view. Be band data have been analyzed from two sounding rocket flights (Bloch et al. 1986, Juda 1988) that viewed seventeen different directions distributed over the northern galactic hemisphere. In Figure 1 the pointing directions of the two flights are indicated on a map from McCammon et al. (1983) of the 130-188 eV B band count rate.
Because ALEXIS is a spinning satellite, it is an ideal platform with which to study the time variability of the EUV cosmos. The main thrusts of this effort are to 1) detect EUV sources at known and unknown locations, 2) provide notification of transients in near real time to enable immediate follow-up from other observatories, and 3) create a time history of observed sources for comparison with previously published catalogs to aid in determining long duration variability from EUV sources.
Los Alamos National Laboratory’s ALEXIS satellite, containing six wide field of view EUV telescopes was launched 1993 April 25. ALEXIS is a sky monitor/survey experiment, and with each 50 s rotation, the satellite’s six telescopes (three energy bands 130, 178 and 186 Å) scan nearly half of the sky. Due to the damage sustained at launch by the satellite, the ALEXIS project team has had to spend over a year devising new methods to determine spacecraft attitude knowledge, essential for putting photons back on the sky correctly. These efforts have been successful. A recent review of the ALEXIS point source effort can be found in the Proceedings of IAU Colloquium 152, 1995. This paper reviews the transient systems that have been observed by ALEXIS which fall into two types: cataclysmic variables and unknown, short duration transients.
We discuss pulse height analysis of Be band data in relation to the important 72 eV Fe line cluster emission from the soft X-ray background (SXRB). Pulse height fits to the Be band data suggest that the Fe lines must be suppressed by a factor of ~10 with respect to the rest of the X-ray spectrum. The broad band rates and the mean energy of the pulse height data for the Be band can be brought into agreement by using depleted elemental abundance emission models. A planned measurement of the SXRB Fe lines using the Array of Low Energy X-ray Imaging Sensors (ALEXIS) experiment could resolve this issue.
Four distinct fossil turtle assemblages (Chelonia) are recognized from the Panama Canal Basin. The oldest, from the late Eocene–early Oligocene Gatuncillo Formation, is dominated by podocnemidid pleurodires. The early Miocene Culebra Formation includes both podocnemidids and trionychids. The early to middle Miocene Cucaracha Formation includes taxa classified in Geoemydidae (including Rhinoclemmys panamaensis n. sp.), Kinosternidae (represented by Staurotypus moschus n. sp.), large testudinids, trionychids, and podocnemidids, and finally, the late Miocene Gatun Formation records cheloniid sea turtles. These fossils include the oldest known representatives of Rhinoclemmys, the oldest record of kinosternids in Central America with a more extensive southern paleodistribution for Staurotypus and staurotypines in general, early occurrences of giant tortoises in the Neotropics, the oldest occurrence of soft-shell turtles in the tropics, the oldest late Eocene–early Oligocene Neotropical occurrences of podocnemidids. The Panamanian fossil turtles represent clades that are primarily endemic to North America, showing their very early arrival into the Neotropics prior to the complete emergence of the Isthmus of Panama, as well as their first contact with Caribbean-South American pleurodires by the early Miocene.
Nolybenum and tungsten metals have been grown on an MBE grown (100)GaAs at various substrate temperatures. RHEED technique was used in situ to analyse the crystalline structure and the growth mechanism of the mechanism of the thin metal films. It was found that Mo epilayers can be grown on the (100) GaAs at temperatures between 150–400°C. The epitaxal arrangement is (111)Mo || (100)GaAs with Mo ||  GaAs. Tungsten films are not growing epitaxially under similar experimental conditions.
Spinel phases Li-Mn-C with Li/Mn ratios between 0.35 and 0.8 were synthesized. The relationships between composition, manganese valence, vacancy fraction and electrochemical capacity are described using a new composition-valence phase diagram. Electrochemical performances in lithium batteries are compared. The best materials showed constant capacit> 140 Ah/kg in the range 3.5/2 V in liquid electrolyte batteries up to 20 cycles, without the usual capacity drop observed in stoichiometric LiMn204.
Ovid regarded the Epistulae Heroidum as a collection with a consistent theme. He indicates as much at Am. 2.18.18–26, where he describes the unified conception of nine or ten of the Heroides as the result of Amor's insistence that he be an elegiac poet:
This study sought to evaluate the benefit of utilizing a nutritionist review of a self-administered food frequency questionnaire (FFQ), to determine whether accuracy could be improved beyond that produced by the self-administered questionnaire alone.
Participants randomized into a dietary intervention trial completed both a FFQ and a 4-day food record (FR) at baseline before entry into the intervention. The FFQ was self-administered, photocopied and then reviewed by a nutritionist who used additional probes to help complete the questionnaire. Both the versions – before nutritionist review and after nutritionist review – were individually compared on specific nutrients to the FR by means, correlations and per cent agreement into quintiles.
Settings and subjects:
Three hundred and twenty-four people, a subset of participants from the Polyp Prevention Trial – a randomized controlled trial examining the effect of a low-fat, high-fibre, high fruit and vegetable dietary pattern on the recurrence of adenomatous polyps – were recruited from clinical centres at the University of Utah, University of Buffalo, Memorial Sloan Kettering Cancer Center in New York and Kaiser Permanente Medical Program in Oakland.
Reviewing the FFQ increased correlations with the FR for every nutrient, and per cent agreement into quintiles for all nutrients except calcium. Energy was underestimated in both versions of the FFQ but to a lesser degree in the version with review.
One must further evaluate whether the increases seen with nutritionist review of the FFQ will enhance our ability to predict diet–disease relationships and whether it is cost-effective when participant burden and money spent utilizing trained personnel are considered.
Notre recherche consiste à concevoir et réaliser une source de flux statique à aimants permanents
générant un champ de 4 à 5 Tesla dans un volume de quelques mm3. Un des aspects novateurs de
cette approche est que nous avons cherché à obtenir un champ magnétique intense (principe du dipôle
ponctuel) et non pas un champ magnétique homogène (principe du dipôle infini utilisé dans les structures
de Leupold/Halbach). Après optimisation du modèle analytique, nous avons discrétisé la structure
de manière à obtenir un modèle réalisable à partir de pavé d'aimants réels. Une originalité du travail
est la recherche d'une géométrie performante et une combinaison de divers matériaux magnétiques durs
(nuances d'aimants Néodyme-Fer-Bore) et de matériau magnétique doux (Fer-Cobalt). Les configurations
particulières d'aimants sont optimisées par simulation numérique grâce à des logiciels complémentaires,
développés par le LEG : DIPOLE-3D (calcul analytique de champ), FLUX2D et FLUX3D (éléments finis).
L'étude de faisabilité du projet a été réalisée en calculant les forces et les champs démagnétisants lors de
la séquence de montage. Le modèle de source actuel fournit un champ atteignant 4,3 T dans un volume de
diamètre de 6 mm pour une hauteur de 2,8 mm et ayant un diamètre extérieur de 100 mm.
Dopamine is one of the major neurotransmitters in the retina. It is released from amacrine and interplexiform cells into both inner (IPL) and outer (OPL) plexiform layers. Several dopaminergic actions are known to occur through D1 receptors (D1R) but the precise location of these receptors has not been established. An antibody that recognizes the intracytoplasmic C-terminal of the rat D1R was used to detect D1R, immunohistochemically, in rats (Wistar and RCS), mouse, hamster, and macaque monkey retinas. The OPL was heavily stained in each species, consistent with the known actions of dopamine on horizontal cells. Three to five bands were observed in the IPL, depending on species. Three were in the a sublayer, the outermost of which was close to the amacrine cell layer, and may represent the massive dopamine input to the AII rod-amacrine cells. As observed in mice, where bipolar cells are D1-immunoreactive, the band located in sublayer 3 of the IPL may contain cone-bipolar cell terminals. A band of D1R-immunoreactivity in the b sublayer of the IPL contains ON-bipolar cell terminals and a second site of interaction between dopaminergic cells and the AII amacrine cells. This sublayer was absent from the RCS rat retina, suggesting a severe impairment of the rod-driven pathway following rod degeneration in these mutant rats. Cells in the ganglion cell layer exhibited relatively heavy staining, and may be ganglion cells or displaced amacrine cells. Some extrasynaptic localizations of D1R in the retina are suggested.
Compositional trends of the Cenomanian Belle Fourche Formation, a marine shale unit in the Western Canada Sedimentary Basin, have been investigated on a regional scale using bulk-rock geochemistry and mineralogy, clay mineral compositions and oxygen isotope geochemistry of shale and bentonite core samples. Smectitic illite-smectite found in the matrix of immature, hemipelagic samples is compositionally and isotopically consistent with an origin from low-temperature alteration of volcanic ash in the central Western Interior Seaway, where the basin received minimal detrital input. The origin of the more illitic matrix in the deeply buried, western, pro-deltaic shales can be interpreted in terms of either diagenetic ‘illitization’ of a smectitic precursor, or depositional mixing of abundant, detrital, illitic material with minor amounts of ashfall-derived smectite. It is concluded that: (1) documented silicate mineral reactions during deep diagenesis of the Belle Fourche Formation took place in a relatively closed system, with no significant import or export of mobile species at the formation scale; and (2) diagenesis and depositional mixing can have similar effects in terms of bulk-rock and oxygen isotope geochemistry, and mineral compositions and assemblages.
The serum antibody response (total, and isotypes IgG1, IgG4, IgM, IgA and IgE) to Guinea worm infection was examined in humans from a highly endemic area of northern Ghana by ELISA and SDSPAGE/Western blot techniques using an adult D. medinensis antigen. Sera were obtained early and late in the peak transmission period, from persons with patent and postpatent infections, as well as from persons from the same endemic area who claimed never to have had Guinea worm infection. To observe for potential cross-reactions in the tests, sera were also obtained from areas with no transmission of Guinea worm from patients with hookworm. O. volvulus and W. bancrofti infections, and from non-infected controls. Sera from persons living in the Guinea worm endemic area reacted extensively with Guinea worm antigen in both tests, and large numbers of bands were produced in the Western blots (up to 35 identified for some sera). For most antibody isotypes, the ELISA absorbance values obtained with sera from the same individuals varied between the two transmission seasons, with the highest titres present towards the end of the peak transmission period. The mean antibody titres for persons in the patent and postpatent infection categories were not significantly different when sera were obtained at the same season of the year. Persons from the endemic area, who claimed never to experience patent infections, also had antibodies to Guinea worm, although at significantly lower mean levels than for the patent and postpatent categories. The highest specificity in the ELISA and the most homogenous Western blots were obtained when detecting for antibodies of the IgG4 isotype.
In 1952 Eysenck threw down the gauntlet, when he claimed that psychoanalytical forms of psychotherapy were no more effective than spontaneous remission. As we trudge through the fourth decade of this debate, its quality remains as divisive and acrimonious as ever. Professor Michael Shepherd (1979, 1980) has latterly taken on Eysenck's mantle, averring that psychotherapy is not only ineffective but may actually harm patients. In an editorial in the British Medical Journal (1984), he launched yet a further attack, arguing on this occasion that the psychotherapist is little more than a ‘placebologist’ exerting his effects through nonspecific means. Why bother with highly trained therapists when an inert pill will produce the same result?