1,374 research outputs found
Continuum Coupling and Pair Correlation in Weakly Bound Deformed Nuclei
We formulate a new Hartree-Fock-Bogoliubov method applicable to weakly bound
deformed nuclei using the coordinate-space Green's function technique. An
emphasis is put on treatment of quasiparticle states in the continuum, on which
we impose the correct boundary condition of the asymptotic out-going wave. We
illustrate this method with numerical examples.Comment: 5 pages, 4 figures, Proceedings of the Japanese French Symposium -
New paradigms in Nuclear Physics, Paris, 29th September - 2nd October, to be
published in Int. J. of Modern Physics
An infrared measurement of chemical desorption from interstellar ice analogues
In molecular clouds at temperatures as low as 10 K, all species except
hydrogen and helium should be locked in the heterogeneous ice on dust grain
surfaces. Nevertheless, astronomical observations have detected over 150
different species in the gas phase in these clouds. The mechanism by which
molecules are released from the dust surface below thermal desorption
temperatures to be detectable in the gas phase is crucial for understanding the
chemical evolution in such cold clouds. Chemical desorption, caused by the
excess energy of an exothermic reaction, was first proposed as a key molecular
release mechanism almost 50 years ago. Chemical desorption can, in principle,
take place at any temperature, even below the thermal desorption temperature.
Therefore, astrochemical net- work models commonly include this process.
Although there have been a few previous experimental efforts, no infrared
measurement of the surface (which has a strong advantage to quantify chemical
desorption) has been performed. Here, we report the first infrared in situ
measurement of chemical desorption during the reactions H + H2S -> HS + H2
(reaction 1) and HS + H -> H2S (reaction 2), which are key to interstellar
sulphur chemistry. The present study clearly demonstrates that chemical
desorption is a more efficient process for releasing H2S into the gas phase
than was previously believed. The obtained effective cross-section for chemical
desorption indicates that the chemical desorption rate exceeds the
photodesorption rate in typical interstellar environments
The small-scale structure of photospheric convection retrieved by a deconvolution technique applied to Hinode/SP data
Solar granules are bright patterns surrounded by dark channels called
intergranular lanes in the solar photosphere and are a manifestation of
overshooting convection. Observational studies generally find stronger upflows
in granules and weaker downflows in intergranular lanes. This trend is,
however, inconsistent with the results of numerical simulations in which
downflows are stronger than upflows through the joint action of gravitational
acceleration/deceleration and pressure gradients. One cause of this discrepancy
is the image degradation caused by optical distortion and light diffraction and
scattering that takes place in an imaging instrument. We apply a deconvolution
technique to Hinode/SP data in an attempt to recover the original solar scene.
Our results show a significant enhancement in both, the convective upflows and
downflows, but particularly for the latter. After deconvolution, the up- and
downflows reach maximum amplitudes of -3.0 km/s and +3.0 km/s at an average
geometrical height of roughly 50 km, respectively. We found that the velocity
distributions after deconvolution match those derived from numerical
simulations. After deconvolution the net LOS velocity averaged over the whole
FOV lies close to zero as expected in a rough sense from mass balance.Comment: 32 pages, 13 figures, accepted for publication in Ap
Geoforensic Analysis of Agba Bridge Failure, Abakaliki, Ebonyi State
A geoforensic analysis of Agba bridge, in Abakaliki, Ebonyi State was carried out using a combination of geotechnical, geophysical and hydrological techniques. The results indicate a highly geotechnically variable, partially weathered meta-sediments as foundation. The weathered profile as confirmed by VES indicated a much thicker weathered soft soil to the south-west. An initial shallow foundation for the South-West Abutment was thus inadequate, leading subsequently to sliding movement, which displaced the reinforced concrete piers. Hydrological analysis of the Agba river revealed critical flow velocities capable of generating local scour of up to 3.5m deep, that equally threaten stability of shallow pier foundation. Accordingly, bored piles extended to 15m have been recommended for the second half of the bridge to the south-west as a remedial measure to guaranty the stability of the structure. Keywords: Geoforensic analysis, bridge failure, scour, geo-electrical sounding, geotechnica
Characterization Studies and Yield Attributes of Some Varieties of Cowpea (\u3cem\u3eVigna unguiculata\u3c/em\u3e L.)
Investigations were carried out on sixteen improved varieties of cowpea (Vigna unguiculata L walp) obtained from International Institute for Tropical Agriculture, Ibadan. These varieties were grown in the Department of Biological Sciences Garden, of the University of Ilorin. Qualitative and quantitative characters were observed for the study. Positive correlations were obtained between leaf number and stem diameter, leaf number and number of seeds per pod, number of branches and plant height. Negative correlation existed between number of pods per plant and number of seed per pod. Analysis of variance (ANOVA) showed significant difference in all the quantitative characters analyzed among the varieties. Each character was also analyzed using Duncan test and F-LSD. The result showed that IT99K-529-1, IT99K – 429 – 2, IT97K – 461 – 4, IT98K – 506 – 1 and IT99K- 1122 were outstanding in term of vegetative and yield performances in Ilorin, Kwara State of Nigeria
Efficacy and safety of long-acting β-agonist/long-acting muscarinic antagonist combinations in COPD:a network meta-analysis
BackgroundThe place of long-acting β agonist/long-acting muscarinic antagonist (LABA/LAMA) combinations in stable patients with COPD is not well defined. The purpose of this study was to systematically review the efficacy and safety of LABA/LAMA combinations.MethodsSeveral databases and manufacturers’ websites were searched for relevant clinical trials. Randomised control trials, at least 12 weeks duration, comparing a LABA/LAMA combination with placebo and/or monotherapy were included. The data were pooled using a network as well as a traditional direct comparison meta-analysis.ResultsTwenty-three trials with a total of 27 172 patients were included in the analysis. LABA/LAMA combinations were associated with a greater improvement in lung function, St. George's Respiratory Questionnaire (SGRQ) score, and Transitional Dyspnoea Index (TDI) than monotherapies. LABA/LAMA combinations were associated with a significantly greater proportion of SGRQ and TDI responders than monotherapies (OR 1.23 (95% credible interval (CrI) 1.06–1.39), OR 1.34 (95% CrI 1.19–1.50) versus LABAs and OR 1.24 (95% CrI 1.11–1.36), OR 1.31 (95% CrI 1.18–1.46) versus LAMAs, respectively) and fewer moderate-to-severe exacerbations compared with LABAs (HR 0.82 (95% CrI 0.73–0.93)), but not when compared with LAMAs (HR 0.92 (95% CrI 0.84–1.00)). There were no statistically significant differences associated with LABA/LAMA combinations compared with monotherapies in safety outcomes as well as in severe exacerbations.ConclusionsThe combination therapy was the most effective strategy in improving lung function, quality of life, symptom scores and moderate-to-severe exacerbation rates, and had similar effects on safety outcomes and severe exacerbations as compared with monotherapies.</jats:sec
Chromospheric polarimetry through multi-line observations of the 850 nm spectral region
Future solar missions and ground-based telescopes aim to understand the
magnetism of the solar chromosphere. We performed a supporting study in
Quintero Noda et al. (2016) focused on the infrared Ca II 8542 A line and we
concluded that is one of the best candidates because it is sensitive to a large
range of atmospheric heights, from the photosphere to the middle chromosphere.
However, we believe that it is worth to try improving the results produced by
this line observing additional spectral lines. In that regard, we examined the
neighbour solar spectrum looking for spectral lines that could increase the
sensitivity to the atmospheric parameters. Interestingly, we discovered several
photospheric lines that greatly improve the photospheric sensitivity to the
magnetic field vector. Moreover, they are located close to a second
chromospheric line that also belongs to the Ca II infrared triplet, i.e. the Ca
II 8498 A line, and enhances the sensitivity to the atmospheric parameters at
chromospheric layers. We conclude that the lines in the vicinity of the Ca II
8542 A line not only increase its sensitivity to the atmospheric parameters at
all layers, but also they constitute an excellent spectral window for
chromospheric polarimetry.Comment: 11 pages, 8 figures, 1 tabl
CaracterĂsticas eritrocitárias do tambaqui Colossoma macropromum (Characidae) em sistema de cultivo intensivo no municĂpio de Macapá, estado do Amapá.
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