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When assessing hepatitis B virus (HBV) status in clinical settings, it is unclear whether self-reports on vaccination history and previous HBV-test results have any diagnostic capacity. Of 3997 participants in a multi-centre HBV-screening study in Paris, France, 1090 were asked questions on their last HBV-test result and vaccination history. Discordance between self-reported history compared with infection status (determined by serology) was calculated for participants claiming ‘negative’, ‘effective vaccine’, ‘past infection’, or ‘chronic infection’ HBV-status. Serological testing revealed that 320 (29.4%) were non-immunised, 576 (52.8%) were vaccinated, 173 (15.9%) had resolved the infection and 21 (1.9%) were hepatitis B surface antigen positive. In total 208/426 (48.8%) participants with a self-reported history of ‘negative’ infection had a discordant serological result, in whom 128 (61.5%) were vaccinated and 74 (35.6%) had resolved infections. A total of 153/599 (25.5%) participants self-reporting ‘effective vaccine’ had a discordant serological result, in whom 100 (65.4%) were non-immunised and 50 (32.7%) were resolved infections. Discordance for declaring ‘past’ or ‘chronic infection’ occurred in 9/55 (16.4%) and 3/10 (30.0%) individuals, respectively. In conclusion, self-reported HBV-status based on participant history is partially inadequate for determining serological HBV-status, especially between negative/vaccinated individuals. More adapted patient education about HBV-status might be helpful for certain key populations.
Combinations of various numerical models and datasets with diverse observation characteristics have been used to assess the mass evolution of ice sheets. As a consequence, a wide range of estimates have been produced using markedly different methodologies, data, approximation methods and model assumptions. Current attempts to reconcile these estimates using simple combination methods are unsatisfactory, as common sources of errors across different methodologies may not be accurately quantified (e.g. systematic biases in models). Here we provide a general approach which deals with this issue by considering all data sources simultaneously, and, crucially, by reducing the dependence on numerical models. The methodology is based on exploiting the different space–time characteristics of the relevant ice-sheet processes, and using statistical smoothing methods to establish the causes of the observed change. In omitting direct dependence on numerical models, the methodology provides a novel means for assessing glacio-isostatic adjustment and climate models alike, using remote-sensing datasets. This is particularly advantageous in Antarctica, where in situ measurements are difficult to obtain. We illustrate the methodology by using it to infer Antarctica’s mass trend from 2003 to 2009 and produce surface mass-balance anomaly estimates to validate the RACMO2.1 regional climate model.
L’œuvre entreprise il y a cinquante ans par l’ancien Comité Permanent de la Carte du Ciel n’a pas été intégralement accomplie. Si certaines de ses parties peuvent être considérées comme terminées, d’autres ont été perdues de vue ou abandonnées.
La tâche de la Commission de la Carte du Ciel doit être maintenant d’examiner, à la lueur de cinquante années de progrès scientifiques, et en tenant compte du travail déjà fait, quelles sont celles des anciennes recommandations du Comité Permanent dont il y a lieu de poursuivre l’exécution.
Much material extending our knowledge of stellar magnitudes has accumulated during the last four years. In the appendix to this report will be found a list of recent catalogues, a summary of the discussion made at Mt Wilson by Seares and the formulae that he finds for the reduction of these catalogues to a fundamental system, until such time as a more extended discussion shall have furnished definitive corrections.
The following summarizes the activities of various members of the Commission in matters pertaining to stellar photometry during the interval 1932-35:
La partie photométrique des trois derniers volumes du Catalogue Astrographique (zone de Catane entre +46° et +55°) est soigneusement dressée sur le système de Miss Leavitt (Harv. Annals, 81). L’erreur moyenne des grandeurs, d’après la réduction de 100 plaques (zones +51° à + 54°, entre 6h et I2h), n’est que de ± om.o8. Nos réductions photométriques ont été effectuées par la formule
D = a-bg+cg2-dg3,
où D dénote le diamètre de l’image photographique et G=8m+g dénote la grandeur de l’étoile.
The committee of the Carte du Ciel in 1910 adopted the following convention : That for Ao stars between magnitudes 5·5 and 6·5 the mean photographic magnitude should equal the mean Harvard visual magnitude. As a corollary, the colour index of Ao stars would then be zero.
The zero point of the photographic magnitudes of the International Polar Sequence was fixed as nearly as possible in accordance with this definition; but it was by no means certain that the magnitudes thus adopted for the few stars of the Sequence represented the zero point defined by all the Ao stars specified.
Assessment of risk and uncertainty is crucial for natural hazard risk management, facilitating risk communication and informing strategies to successfully mitigate our society's vulnerability to natural disasters. Written by some of the world's leading experts, this book provides a state-of-the-art overview of risk and uncertainty assessment in natural hazards. It presents the core statistical concepts using clearly defined terminology applicable across all types of natural hazards and addresses the full range of sources of uncertainty, the role of expert judgement and the practice of uncertainty elicitation. The core of the book provides detailed coverage of all the main hazard types and concluding chapters address the wider societal context of risk management. This is an invaluable compendium for academic researchers and professionals working in the fields of natural hazards science, risk assessment and management and environmental science, and will be of interest to anyone involved in natural hazards policy.
The aim of this study was to evaluate the advantages of the two-step embryo transfer (ET) strategy combining a day 2/3 ET with a day 5/6 blastocyst transfer. In an observational comparative study, 400 infertile women were enrolled from two assisted reproductive technology (ART) units according to inclusion criteria: age below 42 years and at least three embryos obtained on day 2 thus allowing an extended in vitro culture. Two groups were defined according to the ET strategy adopted: group 1 had a two-step ET; and group 2 had a day 2/3 ET with (subgroup 2a) or without (subgroup 2b) blastocysts cryopreserved on day 5/6. Live birth rate was significantly higher in group 1 than in subgroups 2a and 2b (36.5% versus 29.4% and 13.4%, respectively; p < 10−3). Multiple pregnancy rates were comparable between groups. After adjusting on major prognostic factors, the two-step ET strategy was still associated with a significantly higher live birth rate than the day 2/3 ET (OR = 2.23; 95% CI: 1.32–3.77). The two-step ET provides better live birth rates than the cleavage-stage ET. It does not increase multiple pregnancy rates if the number of embryos transferred is limited. It also prevents cycle loss when embryos fail to develop into blastocysts.
Aiming at clarifying the opto-electronic properties of ZnO based n-type Transparent Conducting Oxides, TCOs, properties of ZnO thin films are studied as a function of cationic doping. In addition to commonly reported, Al and Ga trivalent dopant, similar performances are reported for Si doping. In the visible region, ZnO:Si (3 %) thin film exhibit a transmittance higher than 80 % for a resistivity as low as 8x10-4 Ω.cm when grown at 100 °C under 1.0 Pa oxygen pressure. The influence of tetravalent cations as dopant is also investigated through Sn and Ge additions. It shows that not only the oxidation state plays a role but also the cation nature. Indeed, ZnO:Sn thin films are insulating whereas the ZnO:Ge thin films are conductive with resistivity values higher than the ones of ZnO:Si thin films.