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

Ethnic Boundaries and the Margins of the Margin

The theme of this paper is on one of the most elementary questions in the study of ethnicity and nationalism, namely how to approach and assess ethnic boundaries\u27. Should we perceive them as an advantageous or a pernicious tool in politics? To answer that question, we need a reference point; advantageous or pernicious in relation to whom? I will here use those people(-s) who are so marginalized that their voices are practically silenced, and the way in which the political reconstruction, conversion, or deconstruction of ethnic boundaries is favorable or not to them; the margins of the margin. Do ethnic boundaries, and particularly their political usage, illuminate and create preconditions for uplifting, visualization or in any other way favor the margins of the margin? And if yes, how does one handle the element of violence which is involved in the politicization and defense of such boundaries? On the contrary, if we suggest that ethnic boundaries should be deconstructed, how do we deal with the causes of ethnic boundary construction? In order to illuminate these problems, two approaches will be critically discussed and applied: Post-Colonialism and Conflict Resolution

Minimum Riesz energy problems for a condenser with "touching plates"

Minimum Riesz energy problems in the presence of an external field are analyzed for a condenser with touching plates. We obtain sufficient and/or necessary conditions for the solvability of these problems in both the unconstrained and the constrained settings, investigate the properties of minimizers, and prove their uniqueness. Furthermore, characterization theorems in terms of variational inequalities for the weighted potentials are established. The results obtained are illustrated by several examples.Comment: 32 pages, 1 figur

Costing the ex situ conservation of genetic resources: maize and wheat at CIMMYT

Worldwide, the number of genebanks and the amount of seed stored in them has increased substantially over the past few decades. Most attention is focused on the likely benefits from conservation, but conserving germplasm involves costs whose nature and magnitude are largely unknown. In this paper we compile and use a set of cost data for wheat and maize stored in the CIMMYT genebank to address a number of questions. What is the cost of storing an accession of either crop for one more year, or, equivalently what is the benefit in terms of cost savings from eliminating duplicate accessions from the genebank? Relatedly, what is the cost from introducing a new accession into the genebank, given the decision to store it is revisited after one year? Does it make economic sense for CIMMYT to discard accessions that may be available elsewhere? As an extension of this line of inquiry it is possible to value the benefits from either consolidating genebanks or at least networking existing banks to reduce or eliminate duplicate holdings not needed for backup safety purposes. We present estimates of the size and scale economies evident in the CIMMYT operation as a basis for assessing the economics of consolidation. Genebanks represent a commitment to conserve seeds for the very long-run. In this study we report on these long-run costs for the CIMMYT genebank costs that are sensitive to the interest rate used and the protocols for periodically replenishing accessions that are shared with others or regenerating accessions whose viability gradually diminishes with age.Germplasm conservation., Gene banks, Plant., Maize Breeding., Wheat Breeding., Rate of return.,

Diagnostic sérologique de la fasciolose bovine à Fasciola gigantica par un test Elisa en Mauritanie

Depuis la mise en eau des barrages de Diama et de Manantali sur le fleuve Sénégal, les trématodoses du bétail, dont la fasciolose à Fasciola gigantica, ont connu une recrudescence importante. Un test de dépistage sérologique par Elisa qui utilise comme antigène les produits d'excrétion-sécrétion des douves adultes a été développé. Les résultats de ce test ont été comparés à la recherche directe de douves adultes dans les canaux biliaires chez 176 bovins abattus dans la basse vallée du fleuve. Parmi les 40 bovins porteurs de douves adultes, 39 ont été positifs en Elisa. Par ailleurs, 24 bovins ont présenté des titres en anticorps élevés sans douves adultes dans leurs canaux biliaires. Pour 22 de ces 24 animaux, l'abattage a eu lieu entre mars et juillet, période pendant laquelle les bovins s'infestent, suggérant ainsi que l'essentiel des cas de discordance entre le diagnostic par Elisa et la recherche de douves adultes provenait d'un dépistage précoce de l'infestation par la méthode Elisa. La plupart des animaux présentant une infestation monospécifique par d'autres trématodes (Schistosoma bovis ou paramphistomes) n'ont pas eu d'anticorps anti-F. gigantica. Le suivi sérologique et coproscopique d'une cohorte de veaux soumis à une infestation naturelle à proximité du fleuve Sénégal a permis de confirmer que la période d'infestation a lieu de mars à juillet. De plus, une enquête transversale sur 15 troupeaux de bovins de la basse vallée du fleuve a permis de montrer que les deux tiers de ces troupeaux étaient infestés avec des prévalences sérologiques variant de 13 à 33 p. 100. (Résumé d'auteur

Generation of folk song melodies using Bayes transforms

The paper introduces the `Bayes transform', a mathematical procedure for putting data into a hierarchical representation. Applicable to any type of data, the procedure yields interesting results when applied to sequences. In this case, the representation obtained implicitly models the repetition hierarchy of the source. There are then natural applications to music. Derivation of Bayes transforms can be the means of determining the repetition hierarchy of note sequences (melodies) in an empirical and domain-general way. The paper investigates application of this approach to Folk Song, examining the results that can be obtained by treating such transforms as generative models

A 4-D dataset for validation of crystal growth in a complex three-phase material, ice cream

Four dimensional (4D, or 3D plus time) X-ray tomographic imaging of phase changes in materials is quickly becoming an accepted tool for quantifying the development of microstructures to both inform and validate models. However, most of the systems studied have been relatively simple binary compositions with only two phases. In this study we present a quantitative dataset of the phase evolution in a complex three-phase material, ice cream. The microstructure of ice cream is an important parameter in terms of sensorial perception, and therefore quantification and modelling of the evolution of the microstructure with time and temperature is key to understanding its fabrication and storage. The microstructure consists of three phases, air cells, ice crystals, and unfrozen matrix. We perform in situ synchrotron X-ray imaging of ice cream samples using in-line phase contrast tomography, housed within a purpose built cold-stage (-40 to +20oC) with finely controlled variation in specimen temperature. The size and distribution of ice crystals and air cells during programmed temperature cycling are determined using 3D quantification. The microstructural evolution of three-phase materials has many other important applications ranging from biological to structural and functional material, hence this dataset can act as a validation case for numerical investigations on faceted and non-faceted crystal growth in a range of materials

Functional diversity in resource use by fungi.

Fungi influence nutrient cycling in terrestrial ecosystems, as they are major regulators of decomposition and soil respiration. However, little is known about the substrate preferences of individual fungal species outside of laboratory culture studies. If active fungi differ in their substrate preferences in situ, then changes in fungal diversity due to global change may dramatically influence nutrient cycling in ecosystems. To test the responses of individual fungal taxa to specific substrates, we used a nucleotide-analogue procedure in the boreal forest of Alaska (USA). Specifically, we added four organic N compounds commonly found in plant litter (arginine, glutamate, lignocellulose, and tannin-protein) to litterbags filled with decomposed leaf litter (black spruce and aspen) and assessed the responses of active fungal species using qPCR (quantitative polymerase chain reaction), oligonucleotide fingerprinting of rRNA genes, and sequencing. We also compared the sequences from our experiment with a concurrent warming experiment to see if active fungi that targeted more recalcitrant compounds would respond more positively to soil warming. We found that individual fungal taxa responded differently to substrate additions and that active fungal communities were different across litter types (spruce vs. aspen). Active fungi that targeted lignocellulose also responded positively to experimental warming. Additionally, resource-use patterns in different fungal taxa were genetically correlated, suggesting that it may be possible to predict the ecological function of active fungal communities based on genetic information. Together, these results imply that fungi are functionally diverse and that reductions in fungal diversity may have consequences for ecosystem functioning