IMILAST: A community effort to intercompare extratropical cyclone detection and tracking algorithms: assessing method-related uncertainties

The variability of results from different automated methods of detection and tracking of extratropical cyclones is assessed in order to identify uncertainties related to the choice of method. Fifteen international teams applied their own algorithms to the same dataset - the period 1989-2009 of interim European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERAInterim) data. This experiment is part of the community project Intercomparison of Mid Latitude Storm Diagnostics (IMILAST; see www.proclim.ch/imilast/index.html). The spread of results for cyclone frequency, intensity, life cycle, and track location is presented to illustrate the impact of using different methods. Globally, methods agree well for geographical distribution in large oceanic regions, interannual variability of cyclone numbers, geographical patterns of strong trends, and distribution shape for many life cycle characteristics. In contrast, the largest disparities exist for the total numbers of cyclones, the detection of weak cyclones, and distribution in some densely populated regions. Consistency between methods is better for strong cyclones than for shallow ones. Two case studies of relatively large, intense cyclones reveal that the identification of the most intense part of the life cycle of these events is robust between methods, but considerable differences exist during the development and the dissolution phases.

Non-exponential return time distributions for vorticity extremes explained by fractional Poisson processes

Serial correlation of extreme midlatitude cyclones observed at the storm track exits is explained by deviations from a Poisson process. To model these deviations, we apply fractional Poisson processes (FPPs) to extreme midlatitude cyclones, which are defined by the 850 hPa relative vorticity of the ERA interim reanalysis during boreal winter (DJF) and summer (JJA) seasons. Extremes are defined by a 99% quantile threshold in the grid-point time series. In general, FPPs are based on long-term memory and lead to non-exponential return time distributions. The return times are described by a Weibull distribution to approximate the Mittag–Leffler function in the FPPs. The Weibull shape parameter yields a dispersion parameter that agrees with results found for midlatitude cyclones. The memory of the FPP, which is determined by detrended fluctuation analysis, provides an independent estimate for the shape parameter. Thus, the analysis exhibits a concise framework of the deviation from Poisson statistics (by a dispersion parameter), non-exponential return times and memory (correlation) on the basis of a single parameter. The results have potential implications for the predictability of extreme cyclones.

A catalog of high-impact windstorms in Switzerland since 1859

In recent decades, extremely hazardous windstorms have caused enormous losses to buildings, infrastructure and forests in Switzerland. This has increased societal and scientific interest in the intensity and frequency of historical high-impact storms. However, high-resolution wind data and damage statistics mostly span recent decades only. For this study, we collected quantitative (e.g., volumes of windfall timber, losses relating to buildings) and descriptive (e.g., forestry or insurance reports) information on the impact of historical windstorms. To define windstorm severity, normalized and declustered quantitative data were processed by extreme value statistics. Descriptive information was classified using a conceptual guideline. Validation with independent damage information, as well as comparison with wind measurements and a reanalysis, indicates that the most hazardous winter storms are captured, while too few moderate windstorms are detected. Strong storms in the wind measurements and reanalysis are thus added to the catalog. The final catalog encompasses approximately 240 high-impact windstorms in Switzerland since 1859. It features three robust severity classes and contains eight extreme windstorms. Evidence of high winter storm activity in the early and late 20th century compared to the mid-20th century in both damage and wind data indicates a co-variability of hazard and related damage on decadal timescales.

Contrasting interannual and multidecadal NAO variability

Decadal and longer timescale variability in the winter North Atlantic Oscillation (NAO) has considerable impact on regional climate, yet it remains unclear what fraction of this variability is potentially predictable. This study takes a new approach to this question by demonstrating clear physical differences between NAO variability on interannual-decadal (<30 year) and multidecadal (>30 year) timescales. It is shown that on the shorter timescale the NAO is dominated by variations in the latitude of the North Atlantic jet and storm track, whereas on the longer timescale it represents changes in their strength instead. NAO variability on the two timescales is associated with different dynamical behaviour in terms of eddy-mean flow interaction, Rossby wave breaking and blocking. The two timescales also exhibit different regional impacts on temperature and precipitation and different relationships to sea surface temperatures. These results are derived from linear regression analysis of the Twentieth Century and NCEP-NCAR reanalyses and of a high-resolution HiGEM General Circulation Model control simulation, with additional analysis of a long sea level pressure reconstruction. Evidence is presented for an influence of the ocean circulation on the longer timescale variability of the NAO, which is particularly clear in the model data. As well as providing new evidence of potential predictability, these findings are shown to have implications for the reconstruction and interpretation of long climate records.

Role of electrophysiological studies in predicting risk of ventricular arrhythmia in early repolarization syndrome.

BACKGROUND The early repolarization (ER) pattern is associated with an increased risk of arrhythmogenic sudden death. However, strategies for risk stratification of patients with the ER pattern are not fully defined. OBJECTIVES This study sought to determine the role of electrophysiology studies (EPS) in risk stratification of patients with ER syndrome. METHODS In a multicenter study, 81 patients with ER syndrome (age 36 ± 13 years, 60 males) and aborted sudden death due to ventricular fibrillation (VF) were included. EPS were performed following the index VF episode using a standard protocol. Inducibility was defined by the provocation of sustained VF. Patients were followed up by serial implantable cardioverter-defibrillator interrogations. RESULTS Despite a recent history of aborted sudden death, VF was inducible in only 18 of 81 (22%) patients. During follow-up of 7.0 ± 4.9 years, 6 of 18 (33%) patients with inducible VF during EPS experienced VF recurrences, whereas 21 of 63 (33%) patients who were noninducible experienced recurrent VF (p = 0.93). VF storm occurred in 3 patients from the inducible VF group and in 4 patients in the noninducible group. VF inducibility was not associated with maximum J-wave amplitude (VF inducible vs. VF noninducible; 0.23 ± 0.11 mV vs. 0.21 ± 0.11 mV; p = 0.42) or J-wave distribution (inferior, odds ratio [OR]: 0.96 [95% confidence interval (CI): 0.33 to 2.81]; p = 0.95; lateral, OR: 1.57 [95% CI: 0.35 to 7.04]; p = 0.56; inferior and lateral, OR: 0.83 [95% CI: 0.27 to 2.55]; p = 0.74), which have previously been demonstrated to predict outcome in patients with an ER pattern. CONCLUSIONS Our findings indicate that current programmed stimulation protocols do not enhance risk stratification in ER syndrome.

Arctic moisture source for Eurasian snow cover variations in autumn

Eurasian fall snow cover changes have been suggested as a driver for changes in the Arctic Oscillation and might provide a link between sea-ice decline in the Arctic during summer and atmospheric circulation in the following winter. However, the mechanism connecting snow cover in Eurasia to sea-ice decline in autumn is still under debate. Our analysis is based on snow observations from 820 Russian land stations, moisture transport using a Lagrangian approach derived from meteorological re-analyses. We show that declining sea-ice in the Barents and Kara Seas (BKS) acts as moisture source for the enhanced Western Siberian snow depth as a result of changed tropospheric moisture transport. Transient disturbances enter the continent from the BKS region related to anomalies in the planetary wave pattern and move southward along the Ural mountains where they merge into the extension of the Mediterranean storm track.

Daily and seasonal thermal stresses in tilings: a field survey combined with numeric modeling

This study investigates thermally induced tensile stresses in ceramic tilings. Daily and seasonal thermal cycles, as well as, rare but extreme events, such as a hail-storm striking a heated terrace tiling, were studied in the field and by numerical modeling investigations. The field surveys delivered temperature– time diagrams and temperature profiles across tiling systems. These data were taken as input parameters for modeling the stress distribution in the tiling system in order to detect potential sites for material failure. Dependent on the thermal scenario (e.g., slow heating of the entire structure during morning and afternoon, or a rapid cooling of the tiles by a rain storm) the modeling indicates specific locations with high tensile stresses. Typically regions along the rim of the tiling field showed stresses, which can become critical with respect to the adhesion strength. Over the years, ongoing cycles of thermal expansion–contraction result in material fatigue promoting the propagation of cracks. However, the installation of flexible waterproofing membranes (applied between substrate and tile adhesive) represents an efficient technical innovation to reduce such crack propagation as confirmed by both numerical modeling results and microstructural studies on real systems.

Impact of a Reduced Arctic Sea Ice Cover on Ocean and Atmospheric Properties

The Arctic sea ice cover declined over the last few decades and reached a record minimum in 2007, with a slight recovery thereafter. Inspired by this the authors investigate the response of atmospheric and oceanic properties to a 1-yr period of reduced sea ice cover. Two ensembles of equilibrium and transient simulations are produced with the Community Climate System Model. A sea ice change is induced through an albedo change of 1 yr. The sea ice area and thickness recover in both ensembles after 3 and 5 yr, respectively. The sea ice anomaly leads to changes in ocean temperature and salinity to a depth of about 200 m in the Arctic Basin. Further, the salinity and temperature changes in the surface layer trigger a “Great Salinity Anomaly” in the North Atlantic that takes roughly 8 yr to travel across the North Atlantic back to high latitudes. In the atmosphere the changes induced by the sea ice anomaly do not last as long as in the ocean. The response in the transient and equilibrium simulations, while similar overall, differs in specific regional and temporal details. The surface air temperature increases over the Arctic Basin and the anomaly extends through the whole atmospheric column, changing the geopotential height fields and thus the storm tracks. The patterns of warming and thus the position of the geopotential height changes vary in the two ensembles. While the equilibrium simulation shifts the storm tracks to the south over the eastern North Atlantic and Europe, the transient simulation shifts the storm tracks south over the western North Atlantic and North America. The authors propose that the overall reduction in sea ice cover is important for producing ocean anomalies; however, for atmospheric anomalies the regional location of the sea ice anomalies is more important. While observed trends in Arctic sea ice are large and exceed those simulated by comprehensive climate models, there is little evidence based on this particular model that the seasonal loss of sea ice (e.g., as occurred in 2007) would constitute a threshold after which the Arctic would exhibit nonlinear, irreversible, or strongly accelerated sea ice loss. Caution should be exerted when extrapolating short-term trends to future sea ice behavior.

Ästhetische Meerfahrt. Erkundungen zur Beziehung zwischen Literatur und Natur in der Neuzeit

Die Beziehungen zwischen Mensch und Natur durchziehen sämtliche Christian von Zimmermann Kulturräume und werden in den verschiedensten kulturellen Praktiken gestaltet. Dies gilt besonders auch für die Literatur. Sprachliches und besonders auch ästhetisch gestaltetes sprachliches Handeln wird getragen von historisch sich wandelnden Einstellungen zum Meer (Mentalitätsgeschichte), prägt die Beziehung zwischen Mensch und Naturraum (literarische Anthropologie) und kulminiert in der Anforderung an eine ‘rechte Rede’ im Umgang mit der Natur (Naturethik). Unter dem Titel Ästhetische Meerfahrt werden Schlaglichter auf diese Aspekte der Geschichte der Mensch-Meer- Beziehungen im Medium der Literatur geworfen. Dabei stellt die Studie selbst eine Meerfahrt (Essay) dar, die Land- und Seemarken benennt, einzelne Häfen ansteuert, sich aber der offenen Weite des Gewässers bewusst bleibt. Eigene Erkundungen anzuregen, ein naturethisches Denken in die Literaturwissenschaft einzubeziehen, ist Anliegen dieses Buches. Wichtige, teils ausführlich dargelegte Stationen des Buches sind Werke von Olearius, Fleming, Brockes, Gessner, Herder, Goethe, Kosegarten, Heine, Ibsen, Storm, Hauptmann, Keyserling, Kellermann, Fock, Andersch, Cibulka, Theobaldy.

Total Thyroidectomy for Amiodarone-induced Thyrotoxicosis in the Hyperthyroid State.

Amiodarone is a potent antiarrhythmic agent, indicated for the treatment of refractory arrhythmias, which may lead to thyrotoxicosis. In these patients, thyroidectomy is a valid therapeutic option. Antithyroid therapy in the immediate preoperative setting and the subsequently accepted minimal delay until thyroidectomy have not been clearly defined yet. The aim of the present study was to show, that total thyroidectomy under general anaesthesia in patients with amiodarone-induced thyrotoxicosis (AIT) is safe without necessarily obtaining an euthyroid state preoperatively.We conducted a retrospective cohort study of prospectively gathered data on 11 patients undergoing total thyroidectomy under general anaesthesia between January 2008 and December 2013 for AIT at our University Hospital.All patients were preoperatively treated with carbimazole, steroids and β-receptor antagonists. Additionally, 3 patients received potassium perchlorate and in one patient carbimazole was changed to propylthiouracil. Plasmapheresis was performed in 3 patients. Only one patient was euthyroid at the time of operation. There were no significant intra- and postoperative complications, especially no signs of thyroid storm. One patient could postoperatively be removed from the cardiac transplant waiting list due to improved cardiac function.Improvements in the interdisciplinary surgical management for AIT between cardiologists, endocrinologists, anaesthetists and endocrine surgeons provide the basis of safe total thyroidectomy under general anaesthesia in hyperthyroid state. Early surgery without long delay for medical antithyroid treatment (with its potential negative side effects) is recommended.

Internal bacterial colonization of implants: association with peri-implant bone loss

OBJECTIVES The aim of the present longitudinal study was to investigate bacterial colonization of the internal implant cavity and to evaluate a possible association with peri-implant bone loss. METHODS A total of 264 paper point samples were harvested from the intra-implant cavity of 66 implants in 26 patients immediately following implant insertion and after 3, 4, and 12 months. Samples were evaluated for Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Tannerella forsythia as well as total bacterial counts by real-time PCR. Bone loss was evaluated on standardized radiographs up to 25 months after implant insertion. For the statistical analysis of the data, mixed effects models were fitted. RESULTS There was an increase in the frequency of detection as well as in the mean counts of the selected bacteria over time. The evaluation of the target bacteria revealed a significant association of Pr. intermedia at 4 and 12 months with peri-implant bone loss at 25 months (4 months: P = 0.009; 12 months: P = 0.021). CONCLUSIONS The present study could demonstrate a progressive colonization by periodontopathogenic bacteria in the internal cavities of two-piece implants. The results suggest that internal colonization with Pr. intermedia was associated with peri-implant bone loss.

“Crye Fredome”? Medievalism and Twenty-First-Century Scottish National Identity

It is a well-documented fact that the Middle Ages have had a long history of instrumentalisation by nationalisms. 19th-century Eu¬rope in particular witnessed an origins craze during the process of nation-building. In the post-Shoah, post-modern West, on the other hand, we might expect this kind of medievalist master nar¬rative to have been consigned to the dustbin of history. And yet, as nationalism surges again in Europe, negotiations of national identi¬ties in medieval dress seem to have become fashionable once more. In order to come to terms with the fragmented and often contradictory presence of the Middle Ages in these discourses of national identity, I propose we consider medievalism a utilitarian product of the cultural memory. Rather than representing any ‘real’ Middle Ages, then, medievalism tailors available knowledge of the medieval past to the diverse social needs and ideologies of the present. This paper looks at a selection of Scottish examples of present-day medievalism in an attempt to investigate, in particular, the place of the medieval Wars of Scottish Independence in contemporary negotiations of ‘Scottishness’. Both the relationships envisioned between self and other and the role played by ‘the land’ in these cultural, social and political instances of national introspection offer starting points for critical inquiry. Moreover, the analysis of a scholarly intervention in the run-up to the 2014 Scottish independence referendum indicates an intriguing dialogue of academic and non-academic voices in the context of Scottish medievalist cultural memory. We thus find a wide array of uses of the Scottish Middle Ages, some of which feed into the burgeoning nationalism of recent years, while others offer more pensive and ambivalent answers to the question of what it means to be Scottish in the 21st century.

Intravenous Immunoglobulin with Enhanced Polyspecificity Improves Survival in Experimental Sepsis and Aseptic Systemic Inflammatory Response Syndromes.

Sepsis is a major cause for death worldwide. Numerous interventional trials with agents neutralizing single pro-inflammatory mediators have failed to improve survival in sepsis and aseptic systemic inflammatory response syndromes. This failure could well be explained by the widespread gene expression dysregulation known as "genomic storm" in these patients. A multifunctional polyspecific therapeutic agent might be needed to thwart the effects of this "storm". Licensed pooled intravenous immunoglobulin preparations seemed to be a promising candidate but they have also failed in their present form to prevent sepsis-related death. We report here the protective effect of a single dose of intravenous immunoglobulin preparations with additionally enhanced polyspecificity in three models of sepsis and aseptic systemic inflammation. The modification of the pooled immunoglobulin G molecules by exposure to ferrous ions resulted in their newly acquired ability to bind some pro-inflammatory molecules, complement components and endogenous "danger" signals. The improved survival in endotoxemia was associated with serum levels of pro-inflammatory cytokines, diminished complement consumption and normalization of the coagulation time. We suggest that intravenous immunoglobulin preparations with additionally enhanced polyspecificity have a clinical potential in sepsis and related systemic inflammatory syndromes.

Variability of mesospheric water vapor above Bern in relation to the 27-day solar rotation cycle

Many studies investigated solar–terrestrial responses (thermal state, O₃ , OH, H₂O) with emphasis on the tropical upper atmosphere. In this paper the Focus is switched to water vapor in the mesosphere at a mid-latitudinal location. Eight years of water vapor profile measurements above Bern (46.88°N/7.46°E) are investigated to study oscillations with the Focus on periods between 10 and 50 days. Different spectral analyses revealed prominent features in the 27-day oscillation band, which are enhanced in the upper mesosphere (above 0.1 hPa, ∼64 km) during the rising sun spot activity of solar cycle 24. Local as well as zonal mean Aura MLS observations Support these results by showing a similar behavior. The relationship between mesospheric water and the solar Lyman-α flux is studied by comparing thesi-milarity of their temporal oscillations. The H₂O oscillation is negatively correlated to solar Lyman-α oscillation with a correlation coefficient of up to −0.3 to −0.4, and the Phase lag is 6–10 days at 0.04 hPa. The confidence level of the correlation is ≥99%. This finding supports the assumption that the 27-day oscillation in Lyman-α causes a periodical photo dissociation loss in mesospheric water. Wavelet power spectra, cross-wavelet transform and wavelet coherence analysis (WTC)complete our study. More periods of high common wavelet power of H₂O and solar Lyman-α are present when amplitudes of the Lyman-α flux increase. Since this is not a measure of physical correlation a more detailed view on WTC is necessary, where significant (two sigma level)correlations occur intermittently in the 27 and 13-day band with variable Phase lock behavior. Large Lyman-α oscillations appeared after the solar super storm in July 2012 and the H₂O oscillations show a well pronounced anticorrelation. The competition between advective transport and photo dissociation loss of mesospheric water vapor may explain the sometimes variable Phase relationship of mesospheric H₂O and solar Lyman-α oscillations. Generally, the WTC analysis indicates that solar variability causes observable photochemical and dynamical processes in the mid-latitude mesosphere.