Inflammatory mediators in the exhaled breath are receiving growing medical interest as noninvasive disease markers. Volatile organic compounds have been investigated in this context, but clinical information and methodological standards are limited.The levels of ethane, propane, n-pentane, methanol, ethanol, 2-propanol, acetone, isoprene, benzene, toluene, dimethyl sulphide (DMS) and limonene were measured in repeated breath samples from 20 cystic fibrosis patients and 20 healthy controls (aged 8-29 yrs). Three endexhaled and one ambient air sample were collected per person and analysed on a customised gas chromatography system. Intra-subject coefficients of variation ranged between 9 and 34%, and hydrocarbon breath levels were influenced by their inspired concentrations. The alveolar gradient for pentane was higher in cystic fibrosis patients than in healthy controls (0.36 versus 0.21 ppb) and inversely proportional to forced expiratory volume in one second; highest values were observed in patients with pulmonary exacerbations (0.73 versus 0.24 ppb). Cystic fibrosis patients also exhibited a lower output of DMS (3.9 versus 7.6 ppb). Group differences were not significant for ethane and the remaining substances.It was concluded that chemical breath analysis for volatile organic compounds is feasible and may hold potential for the noninvasive diagnosis and follow-up of inflammatory processes in cystic fibrosis lung disease.
<p>The pros and cons of hybrid open access are heavily disputed. A main point of discussion is whether ‘double dipping’ takes place, i.e. paying twice to publish and read the same article. To examine publishers’ assertions that they do not double dip, a survey was conducted of 24 publishers with detailed questions about their pricing policy using hypothetical examples of hybrid open access publication in their journals. The outcome is quite sobering: while a small number of publishers appear to be fully offsetting their hybrid open access income, or making no additional charge for hybrid open access at all, for the rest of those surveyed no clear evidence could be gathered that double dipping does not take place, and many appeared to be double dipping to some extent.</p>
A form of normalisation is presented for the evaluation of citation data on multidisciplinary research. This method is based on the existing classification according to the publishing journals and not on the classification of output according to ISI subject categories. A publication profile is created for each institution to be investigated. This profile accounts for the weight of publications in a journal, represented by the number of publications as a proportion of the total output of the institution. In accordance with this weight, the citation rate of each journal is compared to a qualified relative indicator. The final result is a relative citation rate J, which is the relative perception of the performance of an institution accounting for its publication and citation habits and makes a transdisciplinary comparison possible.
The transition process from the subscription model to the open access model in the world of scholarly publishing brings a variety of challenges to libraries. Within this evolving landscape, the present article takes a focus on budget control for both subscription and publication expenditure with the opportunity to enable the shift from one to the other. To reach informed decisions with a solid base of data to be used in negotiations with publishers, the diverse already-existing systems for managing publications costs and for managing journal subscriptions have to be adapted to allow comprehensive reporting on publication expenditure and subscription expenditure. In the case presented here, two separate systems are described and the establishment of joint reporting covering both these systems is introduced. Some of the results of joint reporting are presented as an example of how such a comprehensive monitoring can support management decisions and negotiations. On a larger scale, the establishment of the National Open Access Monitor in Germany is introduced, bringing together a diverse range of data from several already-existing systems, including, among others, holdings information, usage data, and data on publication fees. This system will enable libraries to access all relevant data with a single user interface.
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