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Essentials Microbe-dependent production of trimethylamine N-oxide (TMAO) contributes to thrombosis risk. The impact of host flavin monooxygenase 3 (FMO3) modulation on platelet function is unknown. Genetic manipulation of FMO3 in mice alters systemic TMAO levels and thrombosis potential. Genetic manipulation of FMO3 is associated with alteration of gut microbial community structure. Summary Background Gut microbes play a critical role in the production of trimethylamine N-oxide (TMAO), an atherogenic metabolite that impacts platelet responsiveness and thrombosis potential. Involving both microbe and host enzymatic machinery, TMAO generation utilizes a metaorganismal pathway, beginning with ingestion of trimethylamine (TMA)-containing dietary nutrients such as choline, phosphatidylcholine and carnitine, which are abundant in a Western diet. Gut microbial TMA lyases use these nutrients as substrates to produce TMA, which upon delivery to the liver via the portal circulation, is converted into TMAO by host hepatic flavin monooxygenases (FMOs). Gut microbial production of TMA is rate limiting in the metaorganismal TMAO pathway because hepatic FMO activity is typically in excess. Objectives FMO3 is the major FMO responsible for host generation of TMAO; however, a role for FMO3 in altering platelet responsiveness and thrombosis potential in vivo has not yet been explored. Methods The impact of FMO3 suppression (antisense oligonucleotide-targeting) and overexpression (as transgene) on plasma TMAO levels, platelet responsiveness and thrombosis potential was examined using a murine FeCl3 -induced carotid artery injury model. Cecal microbial composition was examined using 16S analyses. Results Modulation of FMO3 directly impacts systemic TMAO levels, platelet responsiveness and rate of thrombus formation in vivo. Microbial composition analyses reveal taxa whose proportions are associated with both plasma TMAO levels and in vivo thrombosis potential. Conclusions The present studies demonstrate that host hepatic FMO3, the terminal step in the metaorganismal TMAO pathway, participates in diet-dependent and gut microbiota-dependent changes in both platelet responsiveness and thrombosis potential in vivo.

A novel silver detector incorporated in the Long Duration Exposure Facility (LDEF) has been used to measure the attitude stability of the vehicle. It is thereby established that the LDEF spacecraft maintained a very stable attitude during its nearly 6-year-long flight, notwithstanding a small offset yaw of 8.0 +/- 0.4 deg clockwise from nominal attitude (as viewed from space) and a +/- 0.2-deg oscillation about this offset yaw. LDEF experiments which depend on orientation relative to the forward direction may need to be corrected for the angular offset.

Surgical implant finishing and sterilization procedures were investigated to determine surface characteristics of unalloyed titanium (Ti). All specimens initially were cleaned with phosphoric acid and divided into five groups for comparisons of different surface treatments (C = cleaned as above, no further treatment; CP = C and passivated in nitric acid; CPS = CP and dry-heat sterilized; CPSS = CPS and resterilized; CS = C and dry-heat sterilized). Auger (AES), X-ray photoelectron (XPS), and Raman spectroscopic methods were used to examine surface compositions. The surface oxides formed by all treatments primarily were TiO2, with some Ti2O3 and possibly TiO. Significant concentrations of carbonaceous substances also were observed. The cleaning procedure alone resulted in residual phosphorus, primarily as phosphate groups along with some hydrogen phosphates. A higher percentage of physisorbed water appeared to be associated with the phosphorus. Passivation (with HNO3) alone removed phosphorus from the surface; specimens sterilized without prior passivation showed the thickest oxide and phosphorus profiles, suggesting that passivation alters the oxide characteristics either directly by altering the oxide structure or indirectly by removing moieties that alter the oxide. Raman spectroscopy showed no crystalline order in the oxide. Carbon, oxygen, phosphorus, and nitrogen presence were found to correlate with previously determined surface energy.

SOFCAL is a hybrid instrument with both active and passive chambers to measure the proton and helium cosmic ray spectra from 0.2–10 TeV. An emulsion/x-ray film chamber is situated between a Cerenkov counter and an imaging calorimeter. Scintillating fibers (Sci-Fi) measure the electromagnetic (EM) cascades that develop in the calorimeter and identity the trajectory. The emulsion/x-ray film data provide an in-flight calibration of the Sci-Fi calorimeter. The data reduction techniques will be discussed and interim results of the analysis from a balloon flight will be presented.

High energy cosmic ray interactions were studied by the JACEE Collaboration using balloon‐borne emulsion chambers at high altitude. In high energy, yet low multiplicity interactions many secondary vertices were observed, probably due to decays of short‐lived particles. Early conversions of photons were found in the vicinity of these vertices. Conversion distances and angular distributions of the photons were studied.

We examined the mode of inheritance of rheumatoid arthritis (RA) and estimated the genetic contribution of the HLA-linked locus to the development of RA using data from 111 multiplex families (54 London, 57 Cleveland), and 43 randomly ascertained patients (Seattle). HLA-DR4 was present in 78 multiplex probands (70%); a further 16 probands who were negative for DR4 were positive for DR1. Both DR4 and DR1 were significantly in excess when compared to control population frequencies (P less than 0.001); an additional finding was an excess of DR7, although the numbers of probands with DR7 were small. Despite the well-established HLA association with RA, neither recessive nor additive (dominant) modes of inheritance, nor any intermediate models have been ruled out using affected sib-pair and antigen genotype frequency among patients (AGFAP) methods. However, in our study the AGFAP data for HLA-DR4 and DR1 were close to recessive expectations (P = ns) while an additive (dominant) mode of inheritance was rejected (P less than 0.001). The same results were obtained by an independent method which considered HLA-DR transmission from affected parents to their affected children. The affected sib-pair haplotype sharing method showed deviation from random expectations but did not allow discrimination between recessive and additive (dominant) modes. The effect of the HLA-linked locus on familiarity accounted for only a 1.61-fold increased risk to sibs over the population prevalence, compared to an observed value of 3.90. This indicated that there could be at least one other non-HLA locus predisposing to RA with a weight that is slightly greater than that of HLA.

We review 12 consecutive cases of pre-macular fibrosis (PMF) treated by vitreous surgical techniques. The causes of PMF included retinal detachment surgery in four patients, idiopathic in three patients, laser treatment in three patients, pars planitis in one patient and diabetic retinopathy in one patient. The membrane was successfully removed in all the patients. One patient developed a retinal detachment that was repaired successfully. All patients had improved visual acuity (VA) of two Snellen lines or more and six patients achieved VA of 6/12 or better. Patients with PMF following retinal detachment had poorer final VA.

Direct measurements of cosmic-ray nuclei above 1 TeV/nucleon have been performed in a series of balloon-borne experiments with emulsion chambers. The observed all-particle spectrum above 20 TeV is consistent with the results of the Proton satellite and many air shower experiments. The proton spectrum is consistent with a power law having an index of 2.76 + or - 0.09 up to at least 100 TeV, but an overabundance of helium by a factor of 2 above 2 TeV per nucleon is found when compared with the extrapolation from the low energies. For heavy elements (C through Fe), the intensities around 1 TeV/nucleon are consistent, within the statistical errors, with the extrapolation from lower energy data using the Spacelab 2 spectral indices. An enhancement for the medium-heavy components (C through Ca) above 200 TeV is indicated. The mean mass above 50 TeV indicates slightly higher values than the results of the air shower experiments.

For some X–ray stress measurement applications the photographic film methods may be preferred to diffractometer methods. The principles applied to the former are reviewed and the accuracy and sources of error are examined. The main procedures include the standard ‘two exposure’ method (including the use of the sin2 method), and the use of a relationship depending on the asymmetry of rings at oblique incidence. A number of apparent errors in the literature are explained and resolved. The simplest formula for the second method takes the form s=k.δR. In the most favourable cases the accuracy of stress measurement is of the order of ±30 MN/m2 or ±2 ton f/in2. Larger errors arise for hardened surfaces with microstresses, and are likely to be larger for the second method. Both methods obviously give the most favourable results when sharp diffraction rings are obtained. However with proper care and appreciation of the factors considered, practically usefulresults are obtained under most circumstances. The treatment is illustrated by particular reference to surface residual stress measurement on steels.

A hybrid electronic-counter/emulsion-chamber instrument was exposed to high-energy cosmic rays on a balloon. The data on 105 nucleus-nucleus collisions in the energy range 20-65 GeV/nucleon and for incident nuclear charges Zp in the range of 22 to 28 are presented. Inclusive characteristics of particle production on different targets (plastic, emulsion, and lead) are shown and compared with models based on the superposition of nucleon-nucleus interactions. Features of a subset of the more central collisions with a plastic target and some characteristics of individual events with the highest multiplicity of produced particles are described.

Two unusually-high-multiplicity interactions of high-energy heavy nuclei were observed in a balloon-borne emulsion chamber: an Si(+)AgBr event (4 TeV/nucleon) and a Ca(+)C event (100 TeV/nucleon), with 1015 and 760 charged particles, respectively. The multiplicities and rapidity distributions favor the multichain model but not the wounded-nucleon superposition model. The high average transverse momentum (550-700 MeV/c) and the rapid fluctuations of the events are not readily understood in terms of any superposition models.

Cristallisation dans le systeme triclinique, groupe P1 et affinement jusqu'a R=0,050. La valeur de l'angle diedre decrivant la conformation enveloppe du cycle cyclopentane est de 40,7°

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The tomb of the ancient Pharaoh, Tut-ankh-Amen, was opened some years ago. Lord Carnarvon, who financed the investigations, died shortly after the opening. Lord Westbury fell to his death from the high window of a London flat on February 21, 1930. His son, the Hon. Richard Bethell, had been found dead in his room the previous November. He was secretary to Mr. Howard Carter, one discoverer of Tut-ankh-Amen’s tomb. Many persons who had been connected with the excavations had died previously—M. Benedite, for example, died after participating in the research, and Mrs. Greely committed suicide after visiting the tomb. The Hon. Richard Bethell was the thirteenth person connected with Tut-ankh-Amen's tomb, directly or indirectly, to die, and his father, Lord Westbury, was the fourteenth. The death of Lord Carnarvon, a few weeks after the tomb was opened, stirred the notion that a curse had been placed on the mummy of the Pharaoh, or in his tomb, to menace violators. Succeeding deaths kept the notion alive, and the thirteenth death, of the Hon. Richard Bethell, wrung an opinion from Dr. Mardus, the eminent French Egyptologist. He was convinced that the ancient Egyptians could surround “their mummies with some dynamic force.” Such a force lurked in the tomb of Tut-ankh-Amen. Its nature was unknown, but it had manifested itself in the series of deaths.

I. Introduction. The Parallel Roads of Glen Roy, for long a mystery to men of Science, have received so complete and natural an explanation, due especially to Macculloch, Agassiz, and Jamieson, that one was led to wonder whether water might not have been impounded by ice in a similar way elsewhere in the Highlands, with the formation of similar beaches. Many cases occur of alluvium laid down by glacial lakes, sometimes with the formation of low terraces, but hardly any high level beaches have been traced out comparable with those of Glen Roy. While passing along the west Highland line between Tyndrum and the Moor of Rannoch and along the road from Bridge of Orchy to Kingshouse, Professor Gregory had several times noticed three such terraces, and found beach material upon them. He suggested that I should determine their height and extension, and I had the opportunity to do so in April of 1921. During the very next month, Messrs. John Mathieson and E. B. Bailey undertook the same operation. With the exceptions referred to below, our work is in agreement, but as they used a theodolite the heights they obtained by triangulation must be accepted as far more nearly correct than my aneroid observations. Their results have been presented to the Geological Society of Edinburgh. Loch Tulla lies 8 miles N.N.W. of Tyndrum (see Fig. 1). It is a small loch surrounded by hills rising to a general level of 1500 feet with several points over 3000 feet. The This 250-word extract was created in the absence of an abstract

The results of passive and active radiation measurements on Spacelab-1 are reported. Spacelab-1 was flown on the STS-9 mission, orbited at an altitude of 241 km, with an inclination of 57 deg and 240 hours of flight time. Approximately thirty passive detectors deployed inside the module, in the access tunnel, and outside on the pallet made possible the radiation measurements. The various forms of radiation measured were a low linear energy transfer component ranging from 94 to 133 mrads inside the module (average dose rate of 10.0 mrads/day; about twice the rate of earlier shuttle flights), an average mission dose-equivalent rate of about 18.5 mrem/day (six times higher than earlier flights), accumulated doses of 125 and 128 mrads and a yield of 17 and 12 mrads for passages through the South Atlantic Anomaly. Spacelab-1, because of its low altitude and short duration, was relatively benign in terms of total radiation dose. Some of the measurements such as high-LET particles and neutrons have biological significance and potential effects on future experiments.

Proton‐nucleus interactions at the mean energy of about 45 TeV and nucleus‐nucleus interactions at energies greater than 1 TeV/nucleon are being studied with a balloon born emulsion chamber. The multiplicities of charged secondaries, the fractional energy spectra and transferse momentum distribution of gamma rays, and the rapidity density in the central region are obtained. The features of inelastic proton‐nucleus interactions are as expected from extrapolations of measurements at lower energies. On the other hand, preliminary data on nucleus‐nucleus interactions indicate some features not expected by simple superposition of nucleon‐nucleon interactions. Examples of unusual phenomena include one event with multiplicity Ns=1000 and several events with apparent high PT particle productions.

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The search for cosmic strangelet nuclei was carried out by two experiments with emulsion chambers. A balloon-borne JACEE emulsion chamber was flown at 3.5 g/cm2 for 200 h in Antarctica (JACEE-10 experiment) and the Concorde flights were made by ECHOS at an atmospheric depth of 110 g/cm2 between Paris and New York. No nuclei withZ⩾30 survived after traversing 60–120 g/cm2 of the detector materials in the JACEE instruments. No evidence for a long mean free path were found in the zenith angle distribution forZ/β⩾26 nuclei. The exposure factor used by the JACEE was 72 m2hsr. The intensity upperbounds,I⩽(2.2–9.7)×10−2/m2h sr, were obtained for strangelets having an atmospheric attenuation length of 220−50 g/cm2, which corresponds to the case for mass numberA=100–10000 andZ/β > 13. Concorde experiments (ECHOS) used both a thin and a thick emulsion chamber. The total exposure was 209 m2 h sr and no candidates with chargeZ⩾30 were found. The largest track hadZ/β=28.6±1.29 withβ ∼ 1. Nuclei observed with charge 13⩽Z⩽30 were consistent with the survival intensity of ordinary nuclei. The flux bounds from the ECHOS experiments were I⩽(2.1–5.0) x 10−2/m2h for strangelets with mass number 100⩽A⩽1000.

Emulsion chambers will be flown in the Astromag Facility to measure the cosmic ray composition and spectra to 10 exp 15 eV total energy and to definitively study the characteristics of nucleus-nucleus interactions above 10 exp 12 eV/n. Two configurations of emulsion chambers will be flown in the SCIN/MAGIC experiment. One chamber has an emulsion target and a calorimeter similar to those recently flown on balloons for composition and spectra measurements. The other has an identical calorimeter and a low-density target section optimized for performing rigidity measurements on charged particles produced in interactions. The transverse momenta of charged and neutral mesons, direct hadronic pairs from resonance decays and interference effects, and possible charge clustering in high-density states of matter will be studied.

Results for the cosmic ray hydrogen and helium spectra up to 800 TeV, near the “knee” region, are presented. There is no sign of a break in either the hydrogen or helium spectra. The differential power law slopes are 2.80±0.04 for hydrogen and 2.68±0.06 for helium. With these new H and He measurements, together with earlier reported results for the heavier elements, the sum of the spectra give an all-particle spectrum that is in good agreement with the all-particle spectrum measured using extensive air showers.

Modifications of material surface properties due to interactions with ambient atomic oxygen have been observed on surfaces facing the orbital direction in low earth orbits. Some effects are very damaging to surface optical properties while some are more subtle and even beneficial. Most combustible materials are heavily etched, and some coatings, such as silver and osmium, are seriously degraded or removed as volatile oxides. The growth of oxide films on metals and semiconductors considered stable in dry air was measured. Material removal, surface roughness, reflectance, and optical densities are reported. Effects of temperature, contamination, and overcoatings are noted.

Synthese du compose du titre par addition de Diels Alder de l'anhydride maleique avec le benzyloxymethyl-5cyclopentadiene