543 research outputs found
A compilation of new airborne magnetic and gravity data across Dronning Maud Land, Antarctica.
The evolution of the South Atlantic region including the Weddell Sea and its adjacent areas is of crucialimportance for understanding the processes of the structure and tectonics of the Antarctic lithosphere, its relation to geodynamic processes, especially to the timing and geometry of the initial stages of the Mesozoic break-up between Africa, Antarctica and South America. For unravelling the geological evolution of Antarctica prior to the break-up of Gondwana, the sub-glacial geology is of utmost importance. Understanding the sub-ice geology allows reconstruction of ancient mountain chains (collision zones) across continents, which are separated by large ocean basins in the presentworld. Since only the peaks of the Dronning Maud Land (DML) mountains can be geologically sampled, geophysical methods are required to uncover the geological structure beneath the ice. Therefore, extensive airborne surveys were conducted across DML between 2001 to 2005 to close data gaps and to improve existing data sets
Kinetische Racematspaltung bei der intramolekularen Hydroaminierung mit Titankatalysatoren
Intramolekulare Hydroaminierungen von Aminoalkinen mit unterschiedlichen Metallkomplexen sind in einer Vielzahl publiziert worden. Im Rahmen der vorliegenden Arbeit wurde gezeigt, dass man bei der intramolekularen Hydroaminierung von racemischen Aminoalkinen mit chiralen Titan(IV)-Katalysatoren einen Enantiomerenüberschuss erzielen kann. Bei den Hydroaminierungen mit den β-chriralen Aminoalkinen wurden keine ee-Werte beobachtet, was durch die zu hohen Reaktionsgeschwindigkeiten und die Entfernung des Chiralitätszentrums in β-Position und dem aktiven Zentrum der entsprechenden Katalysatoren hervorgerufen wurde. Diese hohen Reaktionsgeschwindigkeiten sorgten allerdings dafür, dass die intramolekularen Hydroaminierungen mit den eingesetzten Titan(IV)-Katalysatoren bei sehr geringen Temperaturen sehr schnell mit guten Ausbeuten abliefen. Die Reaktionen mit den α-chiralen Aminoalkinen lieferten im Gegensatz zu den β-chiralen Aminoalkinen erheblich bessere Ergebnisse. Erste Enantiomerenüberschüsse wurden mit α- chiralen Aminoalkin und entsprechenden chiralen Titan(IV)-Katalysatoren erzielt. Die Hydroaminierung zum 5-Ring erwies sich als ausgesprochen viel versprechend, da sich hier die Reaktionsgeschwindigkeiten der einzelnen Enantiomere zum Ringschluss ausreichend unterschieden. Auch hier verliefen die Hydroaminierungen bei niedrigen Reaktionstemperaturen und relativ kurzen Reaktionszeiten. Durch Einsatz entsprechender chiraler Katalysatoren konnte sogar eine teilweise dynamisch kinetische Racematspaltung beobachtet werden. Reaktionen mit α-chiralen Aminoalkinen, die zum 6-Ring hydroaminieren, erzielten keine Ergebnisse. Bei diesen Hydroaminierungen ist die Reaktionsgeschwindigkeit zu gering, so dass auch nach mehreren Tagen keine Cyclisierung erzielt wurde
Validity and responsiveness of the EQ-5D in assessing and valuing health status in patients with anxiety disorders
<p>Abstract</p> <p>Background</p> <p>The EQ-5D is a generic questionnaire which generates a health profile as well as index scores for health-related quality of life that may be used in cost-utility analysis.</p> <p>Aims of the study</p> <p>To examine validity and responsiveness of the EQ-5D in patients with anxiety disorders.</p> <p>Methods</p> <p>389 patients with anxiety disorders completed the EQ-5D at baseline and 6-month follow-up. Subjective measures of quality of life (WHOQOL-BREF) and psychopathology (BAI, BDI-II, BSQ, ACQ, MI) were used for comparison. Validity was analyzed by assessing associations between EQ-5D scores and related other scores. Responsiveness was analyzed by calculating effect sizes of differences in scores between baseline and follow-up for 3 groups indicating more, constant or less anxiety. Meaningful difference scores for shifting to less or more anxiety were derived by means of regression analysis.</p> <p>Results</p> <p>88.4% of respondents reported problems in at least one of the EQ-5D dimension at baseline; the mean EQ VAS score was 63.8. The EQ-5D dimension most consistently associated with the measures used for comparison was 'anxiety/depression'. EQ VAS and EQ-5D index scores were highly correlated (|r|>0.5) with scores of the WHOQOL-BREF dimensions 'physical', 'mental' and 'overall' as well as BAI and BDI-II. The EQ-5D index tended to be the most responsive score. Standardized meaningful difference scores were not significantly different between EQ VAS, EQ-5D index and measures used for comparison.</p> <p>Conclusions</p> <p>The EQ-5D seems to be reasonably valid and moderately responsive in patients with anxiety disorders. The EQ-5D index may be suitable for calculating QALYs in economic evaluation of health care interventions for patients with anxiety disorders.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN15716049</p
Impact of SARS-CoV-2 on incidence, treatment and outcome of very preterm born infants in Switzerland: a retrospective, population-based cohort study.
AIMS OF THE STUDY
To assess whether the COVID-19 pandemic caused by SARS-CoV-2 had an impact on incidence, treatment or major adverse short-term outcome of preterm-born infants in Switzerland.
METHODS
Retrospective cohort study of preterm infants born in 2020 based on two independent data sources from the Swiss Federal Statistics Office (FSO) and SwissNeoNet. Based on FSO data, we calculated the odds ratios for extremely preterm (22-27 weeks gestation), very preterm (28-31 weeks gestation), and late preterm (32-36 weeks gestation) births during the pandemic. Based on SwissNeoNet data of infants born between 22 and 31 weeks gestation, we compared infants born during the Swiss lockdown period in 2020 with infants born during the same period between 2015 and 2019, all infants of 2020 with all infants between 2015 and 2019 and infants born to mothers tested SARS-CoV-2 positive and negative. Possible associations with the pandemic were tested using logistic regression adjusted for case-mix. As a control, we compared births of 2019 with those of 2015-2018.
RESULTS
The FSO data revealed equivalent odds for extremely preterm births in 2020 (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.89-1.14), as well as somewhat lower odds ratios for very preterm (OR 0.9, 95% CI 0.82-1.00) and late preterm (OR 0.91, 95% CI 0.88-0.93) births in 2020. A comparison between 2019 and 2015-2018, however, revealed matching odds ratios rendering an association to the pandemic unlikely. In the SwissNeoNet data, 137 infants were born during lockdown in 2020 compared with 134 births per year during 2015-2019. When including all infants, 744 infants were compared to 845 births, respectively. The only difference observed in treatments and short term outcomes between 2020 and the reference years were a higher odds for respiratory distress syndrome (OR 1.6, 95% CI 1.08-2.37) and provision of continuous positive airway pressure (CPAP) (OR 1.39, 95% CI 1.05-1.84).
CONCLUSIONS
Our Swiss population-based analysis did not identify the elsewhere reported association between the COVID-19 pandemic and a reduced preterm birth rate. However, we can confirm a possible link between the COVID-19 pandemic and higher odds of respiratory distress syndrome, possibly coupled with CPAP requirements. Further observation of potential effects of the pandemic on health and health care provision to newborns may however be indicated based on the literature available so far and that our data only covers the first 9 months of the current pandemic
Impact of SARS-CoV-2 on incidence, treatment and outcome of very preterm born infants in Switzerland: a retrospective, population-based cohort study
AIMS OF THE STUDY: To assess whether the COVID-19 pandemic caused by SARS-CoV-2 had an impact on incidence, treatment or major adverse short-term outcome of preterm-born infants in Switzerland.
METHODS: Retrospective cohort study of preterm infants born in 2020 based on two independent data sources from the Swiss Federal Statistics Office (FSO) and SwissNeoNet. Based on FSO data, we calculated the odds ratios for extremely preterm (22-27 weeks gestation), very preterm (28-31 weeks gestation), and late preterm (32-36 weeks gestation) births during the pandemic. Based on SwissNeoNet data of infants born between 22 and 31 weeks gestation, we compared infants born during the Swiss lockdown period in 2020 with infants born during the same period between 2015 and 2019, all infants of 2020 with all infants between 2015 and 2019 and infants born to mothers tested SARS-CoV-2 positive and negative. Possible associations with the pandemic were tested using logistic regression adjusted for case-mix. As a control, we compared births of 2019 with those of 2015-2018.
RESULTS: The FSO data revealed equivalent odds for extremely preterm births in 2020 (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.89-1.14), as well as somewhat lower odds ratios for very preterm (OR 0.9, 95% CI 0.82-1.00) and late preterm (OR 0.91, 95% CI 0.88-0.93) births in 2020. A comparison between 2019 and 2015-2018, however, revealed matching odds ratios rendering an association to the pandemic unlikely. In the SwissNeoNet data, 137 infants were born during lockdown in 2020 compared with 134 births per year during 2015-2019. When including all infants, 744 infants were compared to 845 births, respectively. The only difference observed in treatments and short term outcomes between 2020 and the reference years were a higher odds for respiratory distress syndrome (OR 1.6, 95% CI 1.08-2.37) and provision of continuous positive airway pressure (CPAP) (OR 1.39, 95% CI 1.05-1.84).
CONCLUSIONS: Our Swiss population-based analysis did not identify the elsewhere reported association between the COVID-19 pandemic and a reduced preterm birth rate. However, we can confirm a possible link between the COVID-19 pandemic and higher odds of respiratory distress syndrome, possibly coupled with CPAP requirements. Further observation of potential effects of the pandemic on health and health care provision to newborns may however be indicated based on the literature available so far and that our data only covers the first 9 months of the current pandemic
Selective brain network and cellular responses upon dimethyl fumarate immunomodulation in multiple sclerosis
Background
Efficient personalized therapy paradigms are needed to modify the disease course and halt gray (GM) and white matter (WM) damage in patients with multiple sclerosis (MS). Presently, promising disease-modifying drugs show impressive efficiency, however, tailored markers of therapy responses are required. Here, we aimed to detect in a real-world setting patients with a more favorable brain network response and immune cell dynamics upon dimethyl fumarate (DMF) treatment.
Methods
In a cohort of 78 MS patients we identified two thoroughly matched groups, based on age, disease duration, disability status and lesion volume, receiving DMF (n = 42) and NAT (n = 36) and followed them over 16 months. The rate of cortical atrophy and deep GM volumes were quantified. GM and WM network responses were characterized by brain modularization as a marker of regional and global structural alterations. In the DMF group, lymphocyte subsets were analyzed by flow cytometry and related to clinical and MRI parameters.
Results
Sixty percent (25 patients) of the DMF and 36% (13 patients) of the NAT group had disease activity during the study period. The rate of cortical atrophy was higher in the DMF group (−2.4%) compared to NAT (−2.1%, p < 0.05) group. GM and WM network dynamics presented increased modularization in both groups. When dividing the DMF-treated cohort into patients free of disease activity (n = 17, DMFR) and patients with disease activity (n = 25, DMFNR) these groups differed significantly in CD8+ cell depletion counts (DMFR: 197.7 ± 97.1/μl; DMFNR: 298.4 ± 190.6/μl, p = 0.03) and also in cortical atrophy (DMFR: −1.7%; DMFNR: −3.2%, p = 0.01). DMFR presented reduced longitudinal GM and WM modularization and less atrophy as markers of preserved structural global network integrity in comparison to DMFNR and even NAT patients.
Conclusions
NAT treatment contributes to a reduced rate of cortical atrophy compared to DMF therapy. However, patients under DMF treatment with a stronger CD8+ T cell depletion present a more favorable response in terms of cortical integrity and GM and WM network responses. Our findings may serve as basis for the development of personalized treatment paradigms
Completing Linnaeus's inventory of the Swedish insect fauna: Only 5,000 species left?
Despite more than 250 years of taxonomic research, we still have only a vague idea about the true size and composition of the faunas and floras of the planet. Many biodiversity inventories provide limited insight because they focus on a small taxonomic subsample or a tiny geographic area. Here, we report on the size and composition of the Swedish insect fauna, thought to represent roughly half of the diversity of multicellular life in one of the largest European countries. Our results are based on more than a decade of data from the Swedish Taxonomy Initiative and its massive inventory of the country's insect fauna, the Swedish Malaise Trap Project The fauna is considered one of the best known in the world, but the initiative has nevertheless revealed a surprising amount of hidden diversity: more than 3,000 new species (301 new to science) have been documented so far. Here, we use three independent methods to analyze the true size and composition of the fauna at the family or subfamily level: (1) assessments by experts who have been working on the most poorly known groups in the fauna; (2) estimates based on the proportion of new species discovered in the Malaise trap inventory; and (3) extrapolations based on species abundance and incidence data from the inventory. For the last method, we develop a new estimator, the combined non-parametric estimator, which we show is less sensitive to poor coverage of the species pool than other popular estimators. The three methods converge on similar estimates of the size and composition of the fauna, suggesting that it comprises around 33,000 species. Of those, 8,600 (26%) were unknown at the start of the inventory and 5,000 (15%) still await discovery. We analyze the taxonomic and ecological composition of the estimated fauna, and show that most of the new species belong to Hymenoptera and Diptera groups that are decomposers or parasitoids. Thus, current knowledge of the Swedish insect fauna is strongly biased taxonomically and ecologically, and we show that similar but even stronger biases have distorted our understanding of the fauna in the past. We analyze latitudinal gradients in the size and composition of known European insect faunas and show that several of the patterns contradict the Swedish data, presumably due to similar knowledge biases. Addressing these biases is critical in understanding insect biomes and the ecosystem services they provide. Our results emphasize the need to broaden the taxonomic scope of current insect monitoring efforts, a task that is all the more urgent as recent studies indicate a possible worldwide decline in insect faunas
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Air and shipborne magnetic surveys of the Antarctic into the 21st century
The Antarctic geomagnetics' community remains very active in crustal anomaly mapping. More than 1.5 million line-km of new air- and shipborne data have been acquired over the past decade by the international community in Antarctica. These new data together with surveys that previously were not in the public domain significantly upgrade the ADMAP compilation. Aeromagnetic flights over East Antarctica have been concentrated in the Transantarctic Mountains, the Prince Charles Mountains – Lambert Glacier area, and western Dronning Maud Land (DML) — Coats Land. Additionally, surveys were conducted over Lake Vostok and the western part of Marie Byrd Land by the US Support Office for Aerogeophysical Research projects and over the Amundsen Sea Embayment during the austral summer of 2004/2005 by a collaborative US/UK aerogeophysical campaign. New aeromagnetic data over the Gamburtsev Subglacial Mountains (120,000 line-km), acquired within the IPY Antarctica's Gamburtsev Province project reveal fundamental geologic features beneath the East Antarctic Ice sheet critical to understanding Precambrian continental growth processes. Roughly 100,000 line-km of magnetic data obtained within the International Collaboration for Exploration of the Cryosphere through Aerogeophysical Profiling promises to shed light on subglacial lithology and identify crustal boundaries for the central Antarctic Plate. Since the 1996/97 season, the Alfred Wegener Institute has collected 90,000 km of aeromagnetic data along a 1200 km long segment of the East Antarctic coast over western DML. Recent cruises by Australian, German, Japanese, Russian, British, and American researchers have contributed to long-standing studies of the Antarctic continental margin. Along the continental margin of East Antarctica west of Maud Rise to the George V Coast of Victoria Land, the Russian Polar Marine Geological Research Expedition and Geoscience Australia obtained 80,000 and 20,000 line-km, respectively, of integrated seismic, gravity and magnetic data. Additionally, US expeditions collected 128,000 line-km of shipborne magnetic data in the Ross Sea sector
Growing old at home – A randomized controlled trial to investigate the effectiveness and cost-effectiveness of preventive home visits to reduce nursing home admissions: study protocol [NCT00644826]
<p>Abstract</p> <p>Background</p> <p>Regarding demographic changes in Germany it can be assumed that the number of elderly and the resulting need for long term care is increasing in the near future. It is not only an individual's interest but also of public concern to avoid a nursing home admission. Current evidence indicates that preventive home visits can be an effective way to reduce the admission rate in this way making it possible for elderly people to stay longer at home than without home visits. As the effectiveness and cost-effectiveness of preventive home visits strongly depends on existing services in the social and health system existing international results cannot be merely transferred to Germany. Therefore it is necessary to investigate the effectiveness and cost-effectiveness of such an intervention in Germany by a randomized controlled trial.</p> <p>Methods</p> <p>The trial is designed as a prospective multi-center randomized controlled trial in the cities of Halle and Leipzig. The trial includes an intervention and a control group. The control group receives usual care. The intervention group receives three additional home visits by non-physician health professionals (1) geriatric assessment, (2) consultation, (3) booster session.</p> <p>The nursing home admission rate after 18 months will be defined as the primary outcome. An absolute risk reduction from a 20% in the control-group to a 7% admission rate in the intervention group including an assumed drop out rate of 30% resulted in a required sample size of N = 320 (n = 160 vs. n = 160).</p> <p>Parallel to the clinical outcome measurement the intervention will be evaluated economically. The economic evaluation will be performed from a society perspective.</p> <p>Discussion</p> <p>To the authors' knowledge for the first time a trial will investigate the effectiveness and cost-effectiveness of preventive home visits for people aged 80 and over in Germany using the design of a randomized controlled trial. Thus, the trial will contribute to the existing evidence on preventive home visits especially in Germany.</p
The German MultiCare-study: Patterns of multimorbidity in primary health care – protocol of a prospective cohort study
Background Multimorbidity is a highly frequent condition in older people, but well designed longitudinal studies on the impact of multimorbidity on patients and the health care system have been remarkably scarce in numbers until today. Little is known about the long term impact of multimorbidity on the patients' life expectancy, functional status and quality of life as well as health care utilization over time. As a consequence, there is little help for GPs in adjusting care for these patients, even though studies suggest that adhering to present clinical practice guidelines in the care of patients with multimorbidity may have adverse effects. Methods The study is designed as a multicentre prospective, observational cohort study of 3.050 patients aged 65 to 85 at baseline with at least three different diagnoses out of a list of 29 illnesses and syndromes. The patients will be recruited in approx. 120 to 150 GP surgeries in 8 study centres distributed across Germany. Information about the patients' morbidity will be collected mainly in GP interviews and from chart reviews. Functional status, resources/risk factors, health care utilization and additional morbidity data will be assessed in patient interviews, in which a multitude of well established standardized questionnaires and tests will be performed. Discussion The main aim of the cohort study is to monitor the course of the illness process and to analyse for which reasons medical conditions are stable, deteriorating or only temporarily present. First, clusters of combinations of diseases/disorders (multimorbidity patterns) with a comparable impact (e.g. on quality of life and/or functional status) will be identified. Then the development of these clusters over time will be analysed, especially with regard to prognostic variables and the somatic, psychological and social consequences as well as the utilization of health care resources. The results will allow the development of an instrument for prediction of the deterioration of the illness process and point at possibilities of prevention. The practical consequences of the study results for primary care will be analysed in expert focus groups in order to develop strategies for the inclusion of the aspects of multimorbidity in primary care guidelines
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