Non-invasive measures of regional lung function and their clinical application in thoracic surgery

The decision to operate, or not operate, is a critical step in the care of patients with a thoracic condition that potentially requires surgery. Weighing the risks and benefits of a thoracic operation involves careful assessment of the patient’s lung function and how this may be altered by surgery. This thesis will describe the application of multiple different methods to assess regional lung function in the context of assessing patients who may benefit from thoracic surgery. The patients are those with resectable Non-Small Cell Lung Cancer (NSCLC), interstitial lung disease (ILD), severe emphysema, and pleural thickening. Prediction of postoperative lung function for NSCLC was reported to be most accurate and precise using CT based on a systematic review and meta-analysis but using density and volume changes was found to be unfeasible in a cohort study. The Lobar Segmentation and Parenchymal Analysis modules of the open access Chest Imaging Platform were found not to give reproducible results for lobar lung volume and density. Heterogeneity of specific volume of gas on CT in 2D did not help to discriminate between Usual Interstitial Pneumonia and other types of ILD, but heterogeneity was higher in ILD compared to reported values in health. Measurement of chest wall movement did not show a clinically useful difference between patients with mesothelioma compared to benign pleural thickening. Chest wall motion did not have an association with prognosis in patients with mesothelioma; data provided external validation for the Brims decision tree prognostication. Early dynamic hyperinflation may be associated with symptomatic benefit from lung volume reduction but further study of this is required to confirm this. Key limitations exist in the available technologies; the lack of normal reference ranges is particularly important

Beweise ohne Worte mit jugendlichen Geflüchteten

Der Artikel beschreibt die Möglichkeit sogenannte Beweise ohne Worte in den ergänzenden Zusatzunterricht im Fach Mathematik von minderjährigen Geflüchteten einzubinden. Auf der Grundlage einer qualitativen Untersuchung stellen wir die These auf, dass sich diese gerade zum Einsatz im Unterricht von zumeist ehrenamtlichen Lehrpersonen mit sehr unterschiedlicher Vorbildung eignen. Insbesondere hinsichtlich der Einschätzung des Lernstandes und Mathematikverständnisses der Jugendlichen zeichneten sich Hinweise für einen Erkenntnisgewinn ab

Species information in whistle frequency modulation patterns of common dolphins

Funding for this project was generously provided by the Office of Naval Research Marine Mammals and Biology program.The most flexible communication systems are those of open-ended vocal learners that can acquire new signals throughout their lifetimes. While acoustic signals carry information in general voice features that affect all of an individual's vocalizations, vocal learners can also introduce novel call types to their repertoires. Delphinids are known for using such learned call types in individual recognition, but their role in other contexts is less clear. We investigated the whistles of two closely related, sympatric common dolphin species, Delphinus delphis and Delphinus bairdii, to evaluate species differences in whistle contours. Acoustic recordings of single-species groups were obtained from the Southern California Bight. We used an unsupervised neural network to categorize whistles and compared the resulting whistle types between species. Of the whistle types recorded in more than one encounter, 169 were shared between species and 60 were species-specific (32 D. delphis types, 28 D. bairdii types). Delphinus delphis used 15 whistle types with an oscillatory frequency contour while only one such type was found in D. bairdii. Given the role of vocal learning in delphinid vocalizations, we argue that these differences in whistle production are probably culturally driven and could help facilitate species recognition between Delphinus species.Publisher PDFPeer reviewe

Elite scientists and the global brain drain

There are signs – one is world university league tables – that people increasingly think globally when choosing the university in which they wish to work and study. This paper is an exploration of data on the international brain drain. We study highly-cited physicists, highly-cited bio-scientists, and assistant professors of economics. First, we demonstrate that talented researchers are being systematically funnelled into a small number of countries. Among young economists in the top American universities, for example, 75% did their undergraduate degree outside the United States. Second, the extent of the elite brain drain is considerable. Among the world’s top physicists, nearly half no longer work in the country in which they were born. Third, the USA and Switzerland are per capita the largest net-importers of elite scientists. Fourth, we estimate the migration ‘funnelling coefficient’ at approximately 0.2 (meaning that 20% of top researchers tend to leave their country at each professional stage). Fifth, and against our prior expectations, the productivity of top scientists, as measured by the Hirsch h-index, is similar between the elite movers and stayers. Thus it is apparently not true that it is disproportionately the very best people who emigrate. Sixth, there is extreme clustering of ISI Highly Cited Researchers into particular fields in different universities. Seventh, we debate the questions: are the brain drain and this kind of funnelling good or bad for the world, and how should universities and governments respond? To be presented at the World Universities Conference in Shanghai, October 2007