556 research outputs found

    An atomic hydrogen beam to test ASACUSA's apparatus for antihydrogen spectroscopy

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    The ASACUSA collaboration aims to measure the ground state hyperfine splitting (GS-HFS) of antihydrogen, the antimatter pendant to atomic hydrogen. Comparisons of the corresponding transitions in those two systems will provide sensitive tests of the CPT symmetry, the combination of the three discrete symmetries charge conjugation, parity, and time reversal. For offline tests of the GS-HFS spectroscopy apparatus we constructed a source of cold polarised atomic hydrogen. In these proceedings we report the successful observation of the hyperfine structure transitions of atomic hydrogen with our apparatus in the earth's magnetic field.Comment: 8 pages, 4 figures, proceedings for conference EXA 2014 (Exotic Atoms - Vienna

    The New swiss glacier inventory SGI2010: relevance of Using high-resolution source data in areas dominated by very small glaciers

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    In view of the rapid and accelerating glacier retreat observed in the European Alps during the last decades, the repeated creation of glacier inventories is important to understand the spatio-temporal variability of glacier changes and to support modeling studies. This article presents the latest glacier inventory for the entire Swiss Alps (SGI2010) derived by manual digitization from high-resolution (25 cm) aerial orthophotographs acquired between 2008 and 2011. Its accuracy is assessed by comparing the extents of clean, snow-and/or debris-covered glaciers derived from multiple digitization by several experts. The potential of more precise mapping of debris-covered glaciers is pointed out through the combination of aerial orthophotos with Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques. In order to investigate the accuracy of glacier outlines obtained from medium-resolution satellite remote sensing imagery, a Landsat derived 2003 inventory is directly compared to all glaciers of the eastern Swiss Alps mapped with 2003 aerial orthoimagery. For the Swiss Alps, the total glacierized area mapped for 2010 is 944.3 ±24.1 kmÂČ. Resulting area changes are -362.6 kmÂČ (-27.7%, or -0.75% a⁻Âč) between 1973 and 2010. It is shown that satellite remote sensing techniques using medium-resolution source data misclassified more than 25% in area of very small glaciers (<0.5 kmÂČ). Therefore, use of high-resolution satellite or airborne imagery for future inventory creation in areas dominated by very small glaciers is recommended

    Effectiveness of conservative interventions including exercise, manual therapy and medical management in adults with shoulder impingement: a systematic review and meta-analysis of RCTs.

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    Objective To investigate the effectiveness of conservative interventions for pain, function and range of motion in adults with shoulder impingement. Design Systematic review and meta-analysis of randomised trials. Data sources Medline, CENTRAL, CINAHL, Embase and PEDro were searched from inception to January 2017. Study selection criteria Randomised controlled trials including participants with shoulder impingement and evaluating at least one conservative intervention against sham or other treatments. Results For pain, exercise was superior to non-exercise control interventions (standardised mean difference (SMD) −0.94, 95% CI −1.69 to −0.19). Specific exercises were superior to generic exercises (SMD −0.65, 95% CI −0.99 to −0.32). Corticosteroid injections were superior to no treatment (SMD −0.65, 95% CI −1.04 to −0.26), and ultrasound guided injections were superior to non-guided injections (SMD −0.51, 95% CI −0.89 to −0.13). Nonsteroidal anti-inflammatory drugs (NSAIDS) had a small to moderate SMD of −0.29 (95% CI −0.53 to −0.05) compared with placebo. Manual therapy was superior to placebo (SMD −0.35, 95% CI −0.69 to −0.01). When combined with exercise, manual therapy was superior to exercise alone, but only at the shortest follow-up (SMD −0.32, 95% CI −0.62 to −0.01). Laser was superior to sham laser (SMD −0.88, 95% CI −1.48 to −0.27). Extracorporeal shockwave therapy (ECSWT) was superior to sham (−0.39, 95% CI −0.78 to –0.01) and tape was superior to sham (−0.64, 95% CI −1.16 to −0.12), with small to moderate SMDs. Conclusion Although there was only very low quality evidence, exercise should be considered for patients with shoulder impingement symptoms and tape, ECSWT, laser or manual therapy might be added. NSAIDS and corticosteroids are superior to placebo, but it is unclear how these treatments compare to exercise. This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0

    Utilisation of rehabilitation services for non-migrant and migrant groups of higher working age in Germany - results of the lidA cohort study

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    Background: An ageing and a shrinking labour force implies that the prevention of a premature exit from work due to poor health will become more relevant in the future. Medical rehabilitation is a health service that aims at active participation in working life. The provision of this service will be relevant for an increasing part of the ageing labour force, namely, employees with a migrant background and their different subgroups. Thus, this study examines whether first- and second-generation employees with migrant background differ from non-migrants in their utilisation of rehabilitation services and whether within the subsample of migrant employees, those persons with foreign nationality differ from those with German nationality. Methods: Socially insured employees born in 1959 or 1965 were surveyed nationwide in 2011 as part of the lidA cohort study (n=6303). Survey data of the first study wave were used to identify the dependent variable of the utilisation of rehabilitation (in- and outpatient), the independent variable of migrant status and the covariates of sociodemographic, work- and non-work-related factors. Applying bivariate statistics with tests of independence and block-wise logistic regressions, differences between the groups were investigated. Additionally, average marginal effects were computed to directly compare the adjusted models. Results: The study showed that first-generation migrants had a significantly lower likelihood of utilising outpatient rehabilitation than non-migrants (fully adj. OR 0.42, 95% CI 0.22-0.82) and that average marginal effects indicated higher differences in the full model than in the null model. No significant differences were found between the first- or second-generation migrants and non-migrants when comparing the utilisation of inpatient rehabilitation or any rehabilitation or when analysing German and foreign employees with migrant background (n=1148). Conclusions: Significant differences in the utilisation of outpatient rehabilitation between first-generation migrants and non-migrants were found, which could not be explained by sociodemographic, work- and non-work-related factors. Thus, further factors might play a role. The second-generation migrants resemble the non-migrants rather than their parent generation (first-generation migrants). This detailed investigation shows the heterogeneity in the utilisation of health services such as medical rehabilitation, which is why service sensitive to diversity should be considered

    Dynamic Risk Prediction of 30-Day Mortality in Patients With Advanced Lung Cancer:Comparing Five Machine Learning Approaches

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    International audiencePURPOSE Administering systemic anticancer treatment (SACT) to patients near death can negatively affect their health-related quality of life. Late SACT administrations should be avoided in these cases. Machine learning techniques could be used to build decision support tools leveraging registry data for clinicians to limit late SACT administration. MATERIALS AND METHODS Patients with advanced lung cancer who were treated at the Department of Oncology, Aalborg University Hospital and died between 2010 and 2019 were included (N = 2,368). Diagnoses, treatments, biochemical data, and histopathologic results were used to train predictive models of 30-day mortality using logistic regression with elastic net penalty, random forest, gradient tree boosting, multilayer perceptron, and long short-term memory network. The importance of the variables and the clinical utility of the models were evaluated. RESULTS The random forest and gradient tree boosting models outperformed other models, whereas the artificial neural network–based models underperformed. Adding summary variables had a modest effect on performance with an increase in average precision from 0.500 to 0.505 and from 0.498 to 0.509 for the gradient tree boosting and random forest models, respectively. Biochemical results alone contained most of the information with a limited degradation of the performances when fitting models with only these variables. The utility analysis showed that by applying a simple threshold to the predicted risk of 30-day mortality, 40% of late SACT administrations could have been prevented at the cost of 2% of patients stopping their treatment 90 days before death. CONCLUSION This study demonstrates the potential of a decision support tool to limit late SACT administration in patients with cancer. Further work is warranted to refine the model, build an easy-to-use prototype, and conduct a prospective validation study

    Neolithic flat-based pots from the Carnac Mounds in the light of Cycladic ‘frying pans’

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    A rare type of pottery, found in four single graves under earthen mounds in the Carnac region of Brittany, consists of a circular, flat-based vessel with a near-vertical wall. On the basis of the equipment known from elsewhere in the world, it is possible that the morphology of these dishes is related to processes involved in the production of salt. To help us in exploring their function, we chose to compare these vessels with another enigmatic class of pottery from the Cyclades – the socalled ‘frying pans’ – which seems to have functioned in a similar way, as an object-sign, and has been found in a maritime milieu and in high-status contexts.V zemljeni gomili v regiji Carnac v Bretaniji smo v ĆĄtirih posameznih grobovih odkrili nov tip posode, za katero je značilna kroĆŸna oblika z ravnim dnom in skoraj navpično steno. Na podlagi predmetov, ki jih poznamo drugje po svetu, sklepamo, da je oblika teh skled povezana s pridobivanjem soli. O njihovi uporabi sklepamo s pomočjo primerjav s t.i. ‘ponvami’ s Kikladskega otočja, za katere se zdi, da so jih uporabljali v podobne namene, tudi kot predmet-znak in se pojavljajo v obmorskih okoljih ter v kontekstih, povezanih z viĆĄjim druĆŸbenim slojem

    Base de données I2AF. Inventaires archéozoologiques et archéobotaniques de France: Les étapes d'une création et l'inventaire aujourd'hui

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    International audienceThe increase and dispersal of data produced by research and preventive archaeology shows how important it is to collect and inventory their findings. A project was developed in the 1990s by France’s national centre for scientific research (CNRS) to set up a paper-based inventory of non-flying mammals in France from the Late Glacial to the current day; but it became apparent very quickly that the method used was too limited. An initial digital database called the Inventory of archaeozoology in France (IAF), which took up where the previous project left off, was the fruit of a real inter-institutional partnership and scientific collaboration at national and international levels. A convention was signed wherein France’s Natural history museum agreed to host the database and the Ministry of culture to distribute its contents through the website of the National inventory of natural heritage (INPN). The database was officially recognized as a heritage collection in May 2007 by France’s Natural history museum. It became the I2AF the following year when it integrated archaeobotanical material and this now allows scientists to cross-reference the information with the original archaeozoological data. Each item comprises four files which provide information on the site, the context, the bibliographical references and the archaeozoological and archaeobotanical studies. Excavation reports deposited by the Department of architecture and heritage (DAPA), university works and journals, research reports and specialist publications have since come to enrich this inventory which is still in its infancy.L’augmentation et la dispersion des donnĂ©es de l’archĂ©ologie prĂ©ventive et programmĂ©e dĂ©montrent l’importance de les collecter et de les inventorier. Un projet dĂ©veloppĂ© dans les annĂ©es 1990 par le CNRS visait Ă  mettre en place un inventaire papier des mammifĂšres non-volants en France du Tardiglaciaire Ă  l’époque actuelle mais les limites de la mĂ©thode employĂ©e sont vite apparues. Une premiĂšre base de donnĂ©es informatique appelĂ©e « inventaire archĂ©ozoologique de France » (IAF), reprenant la trame du prĂ©cĂ©dent projet, a Ă©tĂ© crĂ©Ă©e autour d’un vrai partenariat interinstitutionnel et d’échanges scientifiques nationaux et internationaux. Une convention a Ă©tĂ© mise en place entre le MusĂ©um qui l’hĂ©berge et le ministĂšre de la culture pour diffuser les donnĂ©es de cette base sur le site internet de l’INPN. Elle est officiellement reconnue comme collection patrimoniale en mai 2007 par le MusĂ©um et elle devient I2AF l’annĂ©e suivante en intĂ©grant en plus des donnĂ©es archĂ©oozoologiques, des donnĂ©es archĂ©obotaniques permettant Ă  terme de croiser ces informations. Elle est composĂ©e de quatre fiches apportant respectivement des renseignements sur le site, le contexte, les rĂ©fĂ©rences bibliographiques et les Ă©tudes archĂ©ozoologiques et archĂ©obotaniques. Le dĂ©pouillement des rapports de fouille dĂ©posĂ©s Ă  la DAPA, des revues et travaux universitaires ainsi que les rapports d’études et les publications des spĂ©cialistes viennent enrichir cet inventaire qui n’est qu’au commencement de son histoire

    Interfacial photochemistry of biogenic surfactants: a major source of abiotic volatile organic compounds

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    International audience15 Films of biogenic compounds exposed to the atmosphere are ubiquitously found on surfaces of cloud droplets, aerosol particles, buildings, plants, soils, and the ocean. These air/water interfaces host countless amphiphilic compounds concentrated there with respect to bulk water, leading to a unique chemical environment. Here, photochemical processes at the air/water interface of biofilm-containing solutions were studied, demonstrating abiotic VOC production from authentic biogenic 20 surfactants under ambient conditions. Using a combination of online-APCI-HRMS and PTR-ToF-MS, unsaturated and functionalized VOCs were identified and quantified, giving emission fluxes comparable to previous field and laboratory observations. Interestingly, VOC fluxes increased with the decay of microbial cells in the samples, indicating that cell lysis due to cell death was the main source for surfactants, and VOC production. In particular, irradiation of samples containing solely 25 biofilm cells without matrix components exhibited the strongest VOC production upon irradiation. In agreement with previous studies, LC-MS measurements of the liquid phase suggested the presence of fatty acids and known photosensitizers, possibly inducing the observed VOC production via peroxy-radical chemistry. Up to now such VOC emissions were directly accounted to high biological activity in surface waters. However, the obtained results suggest that abiotic photochemistry can 30 lead to similar emissions into the atmosphere, especially in less biologically-active regions. Furthermore, chamber experiments suggested that oxidation (O 3 /OH-radicals) of the photochemically-produced VOCs leads to aerosol formation and growth, possibly affectin

    Climate change alone cannot explain boreal caribou range recession in Quebec since 1850

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    The contraction of species range is one of the most significant symptoms of biodiversity loss worldwide. While anthropogenic activities and habitat alteration are major threats for several species, climate change should also be considered. For species at risk, differentiating the effects of human disturbances and climate change on past and current range transformations is an important step towards improved conservation strategies. We paired historical range maps with global atmospheric reanalyses from different sources to assess the potential effects of recent climate change on the observed northward contraction of the range of boreal populations of woodland caribou (Rangifer tarandus caribou) in Quebec (Canada) since 1850. We quantified these effects by highlighting the discrepancies between different southern limits of the caribou's range (used as references) observed in the past and reconstitutions obtained through the hindcasting of the climate conditions within which caribou are currently found. Hindcasted southern limits moved ~105 km north over time under all reanalysis datasets, a trend drastically different from the ~620 km reported for observed southern limits since 1850. The differences in latitudinal shift through time between the observed and hindcasted southern limits of distribution suggest that caribou range recession should have been only 17% of what has been observed since 1850 if recent climate change had been the only disturbance driver. This relatively limited impact of climate reinforces the scientific consensus stating that caribou range recession in Quebec is mainly caused by anthropogenic drivers (i.e. logging, development of the road network, agriculture, urbanization) that have modified the structure and composition of the forest over the past 160 years, paving the way for habitat-mediated apparent competition and overharvesting. Our results also call for a reconsideration of past ranges in models aiming at projecting future distributions, especially for endangered species. -- Keywords : anthropogenic disturbances ; climate niche ; eastern Canada ; modelling ; Rangifer tarandus caribou ; species distribution model
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