2,939 research outputs found
Excitation and emission spectra of rubidium in rare-gas thin-films
To understand the optical properties of atoms in solid state matrices, the
absorption, excitation and emission spectra of rubidium doped thin-films of
argon, krypton and xenon were investigated in detail. A two-dimensional
spectral analysis extends earlier reports on the excitation and emission
properties of rubidium in rare-gas hosts. We found that the doped crystals of
krypton and xenon exhibit a simple absorption-emission relation, whereas
rubidium in argon showed more complicated spectral structures. Our sample
preparation employed in the present work yielded different results for the Ar
crystal, but our peak positions were consistent with the prediction based on
the linear extrapolation of Xe and Kr data. We also observed a bleaching
behavior in rubidium excitation spectra, which suggests a population transfer
from one to another spectral feature due to hole-burning. The observed optical
response implies that rubidium in rare-gas thin-films is detectable with
extremely high sensitivity, possibly down to a single atom level, in low
concentration samples.Comment: 7 pages, 5 figure
Probing Majorana neutrinos in rare K and D, D_s, B, B_c meson decays
We study lepton number violating decays of charged K, D, D_s, B and B_c
mesons of the form M^+\to {M'}^-\ell^+\ell^+, induced by the existence of
Majorana neutrinos. These processes provide information complementary to
neutrinoless double nuclear beta decays, and are sensitive to neutrino masses
and lepton mixing. We explore neutrino mass ranges m_N from below 1 eV to
several hundred GeV. We find that in many cases the branching ratios are
prohibitively small, however in the intermediate range m_\pi < m_N < m_{B_c},
in specific channels and for specific neutrino masses, the branching ratios can
be at the reach of high luminosity experiments like those at the LHC-b and
future Super flavor-factories, and can provide bounds on the lepton mixing
parameters.Comment: 25 page
Contracting For Personalization
This paper presents a stylized model based on the principal-agent framework in the absence of monetary instrument as a compensation device to agents with privately known production costs. Our results identify a new trade off that arises from alternative compensation devices, as well as the associated implications on firm’s profitability and consumer welfare
Uncertainty analysis of the CPA and a quadrupolar CPA equation of state - With emphasis on CO2
THE COMBINATORIAL EFFECTS OF Azadirachta indica LEAF EXTRACTS WITH AMIKACIN AND TETRACYCLINE AGAINST CLINICALLY IMPORTANT BACTERIA
Antibiotic-resistance is a major threat in the treatment of diseases caused by resistant bacteria. Combination of plant extracts with antibiotics can serve as an alternative to antibiotics. Azadirachta indica (neem plant) has many antimicrobial properties due to the presence of secondary metabolites such as alkaloids and flavonoids. In this study, the combinatorial effects of neem leaf extracts with amikacin and tetracycline against eight clinically important gram-positive and gram-negative pathogens were investigated using the agar well diffusion assay. Synergistic effect of neem leaf extract and tetracycline was observed against Propionibacterium acnes, Bacillus subtilis, and S. pneumoniae with a significant enlargement (p<0.05) in the diameter of the zone of inhibition. However, the same combination showed insignificant inhibition against S. faecalis, Staphylococcus epidermidis, Enterococcus faecalis, and Staphylococcus aureus. The neem leaf extract-amikacin combination showed insignificant antibacterial activity against Staphylococcus aureus, S. epidermidis, S. pneumoniae, and Pseudomonas aeruginosa. An antagonistic effect was observed when Bacillus subtilis was exposed to the same combination as there was a significant reduction (p<0.05) in the zone of inhibition. This study suggests the potential development of the neem leaf extract-tetracycline combination as an antibacterial agent against P. acnes, B. subtilis, and S. pneumoniae. However, this preliminary data requires further investigation and test on a wider range of clinical isolates to make a more decisive conclusion. The antagonistic effect of the neem leaf extract and amikacin suggests that the individual agents are potent as antibacterial agents than the combination
Exploring the multi-humped fission barrier of 238U via sub-barrier photofission
The photofission cross-section of 238U was measured at sub-barrier energies
as a function of the gamma-ray energy using, for the first time, a
monochromatic, high-brilliance, Compton-backscattered gamma-ray beam. The
experiment was performed at the High Intensity gamma-ray Source (HIgS) facility
at beam energies between E=4.7 MeV and 6.0 MeV and with ~3% energy resolution.
Indications of transmission resonances have been observed at gamma-ray beam
energies of E=5.1 MeV and 5.6 MeV with moderate amplitudes. The triple-humped
fission barrier parameters of 238U have been determined by fitting EMPIRE-3.1
nuclear reaction code calculations to the experimental photofission cross
section.Comment: 5 pages, 3 figure
Systematic review on the effects of the physical and social aspects of community pharmacy spaces on service users and staff
AIM: This systematic review aimed to provide new insights into how pharmacy spaces, or the architecture of pharmacies, are experienced by pharmacy service users and staff. The review sought to identify environmental factors which may influence service users' and staff participation in community-based pharmacy health services. METHOD: Ten databases were searched for English language publications, using a combination of search terms relating to pharmacy service users and staff; pharmacy spaces; and health and social care outcomes. Data from the final selected studies were extracted, thematically analysed using a narrative approach and the quality of each study assessed using the Integrated quality Criteria for the Review of Multiple Study designs (ICROMS). RESULTS: 80 articles reporting 80 studies published between 1994 and 2020 were identified; they were from 28 countries, involving around 3234 community pharmacies, 13,615 pharmacy service users, 5056 pharmacists and 78 pharmacy health staff. Most studies (94%) met the ICROMS minimum score, and half did not meet the mandatory quality criteria. Four themes likely to influence service users' and staff experiences of pharmacy health services were identified: (1) privacy; (2) experience of the physical environment; (3) professional image; and (4) risk of error. CONCLUSION: To optimise the delivery and experience of pharmacy health services, these spaces should be made more engaging. Future applied research could focus on optimising inclusive pharmacy design features
N2O and NO dynamics in AOB-enriched and mixed-culture biomass: experimental observations and model calibration
N2O and NO dynamics in AOB-enriched and mixed-culture biomass: Experimental Observations and Model Calibration
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