Electroencephalogram (EEG) signal quality is often compromised by artifacts that corrupt quantitative EEG measurements used in clinical applications and EEG-related studies. Techniques such as ...filtering, regression analysis and blind source separation are often used to remove these artifacts. However, these preprocessing steps do not allow for complete artifact correction. We propose a method for the automated offline-detection of remaining artifacts after preprocessing in multi-channel EEG recordings. In contrast to existing methods it requires neither adaptive parameters varying between recordings nor a topography template. It is suited for short EEG segments and is flexible with regard to target applications. The algorithm was developed and tested on 60 clinical EEG samples of 20 seconds each that were recorded both in resting state and during cognitive activation to gain a realistic artifact set. Five EEG features were used to quantify temporal and spatial signal variations. Two distance measures for the single-channel and multi-channel variations of these features were defined. The global thresholds were determined by three-fold cross-validation and Youden's J statistic in conjunction with receiver operating characteristics (ROC curves). We observed high sensitivity of 95.5%±4.8 and specificity of 88.8%±2.1. The method has thus shown great potential and is promising as a possible tool for both EEG-based clinical applications and EEG-related research.
In this contribution we describe measures for dependence and causality between component processes in multivariate time series in a stationary context. Symmetric measures, such as the partial ...spectral coherence, as well as directed measures, such as the partial directed coherence and the conditional Granger causality index, are described and discussed. These measures are used for deriving undirected and directed graphs (where the vertices correspond to the one-dimensional component processes), showing the inner structure of a multivariate time series. Our interest in these graphs originates from the problem of detecting the focus of an epileptic seizure, based on the analysis of invasive EEG data. An example for such an analysis is given in the last section of this chapter.
A highly enantio‐ and diastereoselective 4+1 annulation between in situ generated ammonium ylides and o‐quinone methides for the synthesis of a variety of 2,3‐dihydrobenzofurans has been developed. ...The key factors controlling the reactivity and stereoselectivity were systematically investigated by experimental and computational means and the energy profiles obtained provide a deeper insight into the mechanistic details of this reaction.
Selective annulation: The first highly enantio‐ and diastereoselective 4+1 annulation protocol between in situ generated ammonium ylides and o‐quinone methides has been developed. This protocol gives access to highly functionalised chiral 2,3‐dihydrobenzofuran derivatives (see scheme).
The Front Cover illustrates the α‐selenocyanation and α‐thiocyanation of various pronucleophiles (β‐ketoesters, oxindoles and β‐ketoacids) with NaSCN or KSeCN as easily accessible inorganic S(e)CN ...sources under oxidative conditions. Dibenzoylperoxide facilitates the coupling of two inherently nucleophilic species by generating electrophilic S(e)CN‐transfer reagents upon oxidation in situ. More information can be found in the Research Article by M. Waser et al.
We herein report a protocol for the α‐thio‐ and α‐seleno‐cyanation of different cyclic β‐ketoesters and oxindoles by using NaSCN or KSeCN as easily accessible inorganic nucleophilic S(e)CN sources ...under oxidative conditions. Key to success for both transformations is the use of dibenzoylperoxide as an oxidant allowing for the coupling of two inherently nucleophilic species under operationally simple conditions in high yields and with broad functional group tolerance.
An operationally simple protocol for the α‐thio/selenocyanation of β‐ketoesters and oxindoles by using NaSCN or KSeCN under oxidative Umpolung conditions has been successfully implemented.
Background In recent years, studies have shown a protective effect of being raised in a farm environment on the development of hay fever and atopic sensitization. Inconsistent data on the relation of ...farming to asthma and wheeze have raised some doubt about a true protective effect. Objective We sought to study the differential effects of farm-associated exposures on specific asthma-related health outcomes. Methods The cross-sectional Prevention of Allergy Risk Factors for Sensitization in Children Related to Farming and Anthroposophic Lifestyle study included 8263 school-age children from rural areas in 5 European countries. Information on farm-related exposures and health outcomes was obtained by using questionnaires. In subsamples allergen-specific IgE and RNA expression of CD14 and Toll-like receptor genes were measured, and dust from children's mattresses was evaluated for microbial components. Results Inverse relations with a diagnosis of asthma were found for pig keeping (odds ratio OR, 0.57; 95% CI, 0.38-0.86), farm milk consumption (OR, 0.77; 95% CI, 0.60-0.99), frequent stay in animal sheds (OR, 0.71; 95% CI, 0.54-0.95), child's involvement in haying (OR, 0.56; 95% CI, 0.38-0.81), and use of silage (OR, 0.55; 95% CI, 0.31-0.98; for nonatopic asthma) and in Germany for agriculture (OR, 0.34; 95% CI, 0.22-0.53). Protective factors were related with higher expression levels of genes of the innate immunity. Potential risk factors for asthma and wheeze were also identified in the farm milieu. Levels of endotoxin and extracellular polysaccharides were related to the health outcomes independently of the farm exposures. Conclusions The protective effect of being raised in a farm environment was ascribed to distinct exposures. Clinical implications The development of atopic sensitization and atopic and nonatopic asthma is most likely determined by different environmental factors, possibly reflecting distinct pathomechanisms.
Flood hazard mapping is currently in a transitional phase involving the use of data and methods that were traditionally in the domain of local studies in a regional or nationwide context. Challenges ...include the representation of local information such as hydrological particularities and small hydraulic structures, as well as computational and labour costs. This paper proposes a methodology of flood hazard mapping that merges the best of the two worlds (local and regional studies) based on experiences in Austria. The analysis steps include (a) quality control and correction of river network and catchment boundary data; (b) estimation of flood discharge peaks and volumes on the entire river network; (c) creation of a digital elevation model (DEM) that is consistent with all relevant flood information, including riverbed geometry; and (d) simulation of inundation patterns and velocities associated with a consistent flood return period across the entire river network. In each step, automatic methods are combined with manual interventions in order to maximise the efficiency and at the same time ensure estimation accuracy similar to that of local studies. The accuracy of the estimates is evaluated in each step. The study uses flood discharge records from 781 stations to estimate flood hazard patterns of a given return period at a resolution of 2 m over a total stream length of 38 000 km. It is argued that a combined local–regional methodology will advance flood mapping, making it even more useful in nationwide or global contexts.
Background Farm milk consumption has been identified as an exposure that might contribute to the protective effect of farm life on childhood asthma and allergies. The mechanism of action and the role ...of particular constituents of farm milk, however, are not yet clear. Objective We sought to investigate the farm milk effect and determine responsible milk constituents. Methods In rural regions of Germany, Austria, and Switzerland, a comprehensive questionnaire about farm milk consumption and other farm-related exposures was completed by parents of 8334 school-aged children, and 7606 of them provided serum samples to assess specific IgE levels. In 800 cow's milk samples collected at the participants' homes, viable bacterial counts, whey protein levels, and total fat content were analyzed. Asthma, atopy, and hay fever were associated to reported milk consumption and for the first time to objectively measured milk constituents by using multiple regression analyses. Results Reported raw milk consumption was inversely associated to asthma (adjusted odds ratio aOR, 0.59; 95% CI, 0.46-0.74), atopy (aOR, 0.74; 95% CI, 0.61-0.90), and hay fever (aOR, 0.51; 95% CI, 0.37-0.69) independent of other farm exposures. Boiled farm milk did not show a protective effect. Total viable bacterial counts and total fat content of milk were not significantly related to asthma or atopy. Increased levels of the whey proteins BSA (aOR for highest vs lowest levels and asthma, 0.53; 95% CI, 0.30-0.97), α-lactalbumin (aOR for interquartile range and asthma, 0.71; 95% CI, 0.52-0.97), and β-lactoglobulin (aOR for interquartile range and asthma, 0.62; 95% CI, 0.39-0.97), however, were inversely associated with asthma but not with atopy. Conclusions The findings suggest that the protective effect of raw milk consumption on asthma might be associated with the whey protein fraction of milk.
Injuries of the nasal vestibular skin caused by the rotating burr shafts can represent a tedious complication following endonasal drilling and is experienced sooner or later by every rhino-surgeon.
...To protect the nasal entrance from laceration by the free rotating drill shaft we position an otology speculum in the nasal entrance. The speculum is held in place by the scrub nurse during the critical phase of bone drilling.
Following the introduction of the ear speculum protection, we successfully treated our dacryocystostamia procedures (n = 27) and median maxillectomia procedures (n = 6) without any further soft tissue erosions.
Preventive measures for injuries by endonasal drilling procedures are not reported extensively in literature. This stands in contrast to the fact that these injuries are prone to cause significant suffering as amply described in the case of nostril laceration due to nasogastric intubation or nasogastric feeding tubes.
The use of a readily available, reusable ear speculum in endonasal drill application eliminated the complication of nasal entrance lacerations throughout our institution, hitherto.
PDF
