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Antibiotics in acute bronchitis: a meta-analysis.
PurposeMost patients with acute bronchitis who seek medical care are treated with antibiotics, although the effectiveness of this intervention is uncertain. We performed a meta-analysis of randomized, controlled trials to estimate the effectiveness of antibiotics in the treatment of acute bronchitis.Subjects and methodsEnglish-language studies published January 1966 to April 1998 were retrieved using MEDLINE, bibliographies, and consultation with experts. Only randomized trials that enrolled otherwise healthy patients with a diagnosis of acute bronchitis, used an antibiotic in the treatment group and a placebo in the control group, and provided sufficient data to calculate an effect size were included.ResultsWe identified eight randomized controlled trials that satisfied all inclusion criteria. These studies used one of three antibiotics (erythromycin, doxycycline, trimethoprim/sulfamethoxazole). The use of antibiotics decreased the duration of cough and sputum production by approximately one-half day (summary effect size 0.21; 95% CI, 0.05 to 0.36). For specific symptoms, there were nonsignificant trends favoring the use of antibiotics: a decrease of 0.4 days of purulent sputum (95% CI, -0.1 to 0.8), a decrease of 0.5 days of cough (95% CI, -0.1 to 1.1), and a decrease of 0.3 days lost from work (95% CI, -0.6 to 1.1).ConclusionThis meta-analysis suggests a small benefit from the use of the antibiotics erythromycin, doxycycline, or trimethoprim/sulfamethoxazole in the treatment of acute bronchitis in otherwise healthy patients. As this small benefit must be weighed against the risk of side effects and the societal cost of increasing antibiotic resistance, we believe that the use of antibiotics is not justified in these patients
Single File Diffusion enhancement in a fluctuating modulated 1D channel
We show that the diffusion of a single file of particles moving in a
fluctuating modulated 1D channel is enhanced with respect to the one in a bald
pipe. This effect, induced by the fluctuations of the modulation, is favored by
the incommensurability between the channel potential modulation and the moving
file periodicity. This phenomenon could be of importance in order to optimize
the critical current in superconductors, in particular in the case where mobile
vortices move in 1D channels designed by adapted patterns of pinning sites.Comment: 4 pages, 4 figure
Initiating University Reform: Experience from Sub-Saharan Africa.
A journal article.The rapid numerical growth of African universities has prompted little evolution in institutional forms. Some universities may embrace a specialized disciplinary focus such as agriculture, education or science and technology, but in structure and process they remain remarkably similar. Little institutional differentiation has occurred within higher education systems, and legacies from the pre-independence era still shape the form and substance of African universities in important ways. These include the high cost model of publicly funded residential instruction, strong curricular emphasis on the humanities and social sciences, and an elitist orientation. As a result, these systems have been hard pressed to meet the rapidly rising social demand for access to university education in a context of significant economic, political and technological change.
The challenge is daunting, but African governments and their universities have begun to respond. What lessons can be learned from this emerging experience? The following discussion draws upon current examples of promising practice to suggest options for African governments, universities and donors to consider in their efforts to foster higher education reform
The evolution of sperm morphometry in pheasants
Postcopulatory sexual selection is thought to be a potent evolutionary force driving the
diversification of sperm shape and function across species. In birds, insemination and
fertilisation are separated in time and sperm storage increases the duration of sperm
female interaction and hence the opportunity for sperm competition and cryptic female
choice. We performed a comparative study of 24 pheasant species (Phasianidae,
Galliformes) to establish the relative importance of sperm competition and the duration of
sperm storage for the evolution of sperm morphometry (i.e. size of different sperm traits).
We found that sperm size traits were negatively associated with the duration of sperm
storage but were independent of the risk of sperm competition estimated from relative
testis mass. Our study emphasises the importance of female reproductive biology for the
evolution of sperm morphometry particularly in sperm storing taxa
Spectral Features of the Proximity Effect
We calculate the local density of states (LDOS) of a superconductor-normal
metal sandwich at arbitrary impurity concentration. The presence of the
superconductor induces a gap in the normal metal spectrum that is proportional
to the inverse of the elastic mean free path for rather clean systems. For
a mean free path much shorter than the thickness of the normal metal, we find a
gap size proportional to that approaches the behavior predicted by the
Usadel equation (diffusive limit).Comment: LT22 proceeding
Kinetic modelling of runaway electron avalanches in tokamak plasmas
Runaway electrons (REs) can be generated in tokamak plasmas if the
accelerating force from the toroidal electric field exceeds the collisional
drag force due to Coulomb collisions with the background plasma. In ITER,
disruptions are expected to generate REs mainly through knock-on collisions,
where enough momentum can be transferred from existing runaways to slow
electrons to transport the latter beyond a critical momentum, setting off an
avalanche of REs. Since knock-on runaways are usually scattered off with a
significant perpendicular component of the momentum with respect to the local
magnetic field direction, these particles are highly magnetized. Consequently,
the momentum dynamics require a full 3-D kinetic description, since these
electrons are highly sensitive to the magnetic non-uniformity of a toroidal
configuration. A bounce-averaged knock-on source term is derived. The
generation of REs from the combined effect of Dreicer mechanism and knock-on
collision process is studied with the code LUKE, a solver of the 3-D linearized
bounce-averaged relativistic electron Fokker-Planck equation, through the
calculation of the response of the electron distribution function to a constant
parallel electric field. This work shows that the avalanche effect can be
important even in non-disruptive scenarios. RE formation through knock-on
collisions is found to be strongly reduced when taking place off the magnetic
axis, since trapped electrons cannot contribute to the RE population. The
relative importance of the avalanche mechanism is investigated as a function of
the key parameters for RE formation; the plasma temperature and the electric
field strength. In agreement with theoretical predictions, the simulations show
that in low temperature and E-field knock-on collisions are the dominant source
of REs and can play a significant role for RE generation, including in
non-disruptive scenarios.Comment: 23 pages, 12 figure
Ethnic differences in results of fertility and mother’s health care: Portuguese population and Cape Verdeans living in Portugal
This paper pursues a comparison between sociographic profiles and birthcare conditions related to the Portuguese and Cape Verdean mothers living in Portugal, considering the cultural and ethnic variables as determinants to possible distinctions.
Based on the live birth Survey, the Fertility Survey results and the Population Census (official statistics produced by the National Statistics Institute), a statistical analysis was performed, namely, a K-means Cluster Analysis and a Multiple Correspondence Analysis (MCA). We adopted a longitudinal and comparative perspective in the 1995-2013 period. Furthermore, a synchronic analysis approach has been underlined, thoroughly exploring the database of entries of live births for the year 2013.
Despite the fertility rate being lower in the Portuguese population, there is a tendency for convergence between the fertility patterns of both populations, which reveals a porosity of the the Cape Verdean population by incorporating a different fertility model from the one that exists in their country of origin.
Fertility occurs later in the Portuguese women compared with the Cape Verdeans. Differences were also observed in both populations, regarding the sociographic profiles, the birthcare conditions and, finally, the marital status and family structure.info:eu-repo/semantics/acceptedVersio
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