The problem of the optimal combination of rain‐gauge measurements and radar precipitation estimates has been investigated. A method that attempts to generalize well‐established geostatistical ...techniques, such as kriging with external drift, is presented. The new method, besides allowing spatial information to be incorporated into the modelling and estimation process, also allows temporal information to be incorporated. This technique employs temporal data as secondary co‐kriged variables. The approach can be considered both straightforward and practical as far as design and programming aspects are concerned. Co‐kriging with external drift leads to significant improvements in the results compared with typical radar estimates. It also seems to be more advantageous than kriging with external drift in modelling stability terms. Evidence is provided showing the advantages of co‐kriging with external drift modelling over kriging with external drift. The difference becomes particularly pronounced for non‐robust input data. The theoretical background and mathematical structure of the method is demonstrated. The method has been applied to four events, three during summer and one during winter, that took place over the complex Swiss orography. It is shown that cross‐validation skill scores improve when the aggregation period of the input data increases from ten minutes to one hour. This improvement can be attributed to the increasing robustness of the input data with the period of aggregation. Moreover, a straightforward disaggregation scheme, which starts from hourly precipitation maps, produced by means of the aforementioned geostatistical technique and generating precipitation estimates at a temporal resolution of five minutes, is proposed.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Mineral dust is the dominant natural ice nucleating aerosol. Its ice nucleation efficiency depends on the mineralogical composition. We show the first sensitivity studies with a global climate model ...and a three-dimensional dust mineralogy. Results show that, depending on the dust mineralogical composition, coating with soluble material from anthropogenic sources can lead to quasi-deactivation of natural dust ice nuclei. This effect counteracts the increased cloud glaciation by anthropogenic black carbon particles. The resulting aerosol indirect effect through the glaciation of mixed-phase clouds by black carbon particles is small (+0.1Wm−2 in the shortwave top-of-the-atmosphere radiation in the northern hemisphere).
Modelling spatial covariance is an essential part of all geostatistical methods. Traditionally, parametric semivariogram models are fit from available data. More recently, it has been suggested to ...use nonparametric correlograms obtained from spatially complete data fields. Here, both estimation techniques are compared. Nonparametric correlograms are shown to have a substantial negative bias. Nonetheless, when combined with the sample variance of the spatial field under consideration, they yield an estimate of the semivariogram that is unbiased for small lag distances. This justifies the use of this estimation technique in geostatistical applications. Various formulations of geostatistical combination (Kriging) methods are used here for the construction of hourly precipitation grids for Switzerland based on data from a sparse realtime network of raingauges and from a spatially complete radar composite. Two variants of Ordinary Kriging (OK) are used to interpolate the sparse gauge observations. In both OK variants, the radar data are only used to determine the semivariogram model. One variant relies on a traditional parametric semivariogram estimate, whereas the other variant uses the nonparametric correlogram. The variants are tested for three cases and the impact of the semivariogram model on the Kriging prediction is illustrated. For the three test cases, the method using nonparametric correlograms performs equally well or better than the traditional method, and at the same time offers great practical advantages. Furthermore, two variants of Kriging with external drift (KED) are tested, both of which use the radar data to estimate nonparametric correlograms, and as the external drift variable. The first KED variant has been used previously for geostatistical radar-raingauge merging in Catalonia (Spain). The second variant is newly proposed here and is an extension of the first. Both variants are evaluated for the three test cases as well as an extended evaluation period. It is found that both methods yield merged fields of better quality than the original radar field or fields obtained by OK of gauge data. The newly suggested KED formulation is shown to be beneficial, in particular in mountainous regions where the quality of the Swiss radar composite is comparatively low. An analysis of the Kriging variances shows that none of the methods tested here provides a satisfactory uncertainty estimate. A suitable variable transformation is expected to improve this.
Fragestellung:
In Familien mit ausreichenden psychosozialen und materiellen Ressourcen erfahren Kinder eine anregende Umwelt, in der sie sich entsprechend ihren Bedürfnissen entwickeln können. Wenn ...Eltern jedoch Belastungen ausgesetzt sind, kann ein Mangel an Ressourcen die frühkindliche Entwicklung – auch längerfristig betrachtet – negativ beeinflussen. In der Fachliteratur wird eine Reihe an spezifischen familiären Risikofaktoren im Hinblick auf die Kindergesundheit beschrieben. Hebammen betreuen Familien mit unterschiedlichem Unterstützungsbedarf und sind insofern prädestiniert, familiäre Risikofaktoren früh zu erkennen. Hier wird der Frage nachgegangen, wie oft solche Risikofaktoren durch frei praktizierenden Hebammen in der Schweiz während der postpartalen Betreuung erkannt und angegeben werden.
Methodik:
Zur Beantwortung der Fragestellung werden Daten aus der Tätigkeitserfassung der frei praktizierenden Hebammen des Schweizerischen Hebammenverbandes (SHV) im Jahr 2014 hinzugezogen. Die Daten werden deskriptiv ausgewertet.
Ergebnis:
Im Beitrag wird gezeigt, wie oft in der Literatur beschriebene Risikofaktoren, wie beispielsweise ein tiefer Ausbildungsstand der Mutter oder materielle Armut, bei den betreuten Frauen und Kindern gemäss den Angaben der Hebammen vorkommen. Ausserdem wird anhand eines Summenscores dargestellt wie häufig mehrere solche Belastungen gleichzeitig auftreten.
Schlussfolgerung:
Die Resultate liefern Hinweise auf die Häufigkeit von Risikofaktoren in Bezug auf die Kindergesundheit bei Familien in der Schweiz kurz nach der Geburt, sowie auf die Erkennung derselben durch frei praktizierende Hebammen bei ihrer Tätigkeit in der postpartalen Betreuung. Daraus werden Empfehlungen für die weiterführende Forschung abgeleitet.
A sensitive and highly automated high-performance liquid chromatography (HPLC) column-switching method has been developed for the simultaneous determination of the active metabolite III and its ...prodrug II, both derivatives of the oral platelet inhibitor Ro 48-3657 (I), in plasma and urine of man and dog. Plasma samples were deproteinated with perchloric acid (0.5
M), while urine samples could be processed directly after dilution with phosphate buffer. The prepared samples were injected onto a pre-column of a HPLC column switching system. Polar plasma or urine components were removed by flushing the precolumn with phosphate buffer (0.1
M, pH 3.5). Retained compounds (including II and III) were backflushed onto the analytical column, separated by gradient elution and detected by means of UV detection at 240 nm. The limit of quantification for both compounds was 1 ng/ml (500 μl of plasma) and 25 ng/ml (50 μl of urine) for plasma and urine, respectively. The practicability of the new method was demonstrated by the analysis of about 6000 plasma and 1300 urine samples from various toxicokinetic studies in dogs and phase 1 studies in man.
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A sensitive and specific high-performance liquid chromatographic method has been developed to measure the catechol-O-methyl-transferase (COMT) inhibitor 3,4-dihydroxy-4'-methyl-5-nitrobenzophenone ...(Ro 40-7592) in human plasma. The compound and the internal standard were extracted from plasma at pH 2 with n-butyl chloride-ethyl acetate (95:5, v/v). The extract was chromatographed on a reversed-phase column (Hypersil ODS, 5 microns) using a mixture of phosphate buffer (0.05 M, pH 2), methanol and tetrahydrofuran (45:55:5, v/v/v) as the mobile phase. Long-retained components were removed from the system by means of a simple column-switching system. Quantification of the catechol-O-methyltransferase inhibitor was performed by means of coulometric detection (0.1 V). The limit of quantification was about 1 ng/ml, using a 1-ml specimen of plasma. The recovery from human plasma was greater than 88%. The mean inter-assay precision was 5.3% in the range 2.5-1000 ng/ml. Linearity of the standard curve was obtained in the concentration range 2.5-500 ng/ml. The catechol-O-methyltransferase inhibitor was stable in human plasma when stored for six months at -20 degrees C and for 24 h at room temperature. The practicability of the new method was demonstrated by the analysis of more than 400 plasma samples from a tolerance study performed in human volunteers.
An highly sensitive and fully automated high-performance liquid chromatographic assay was developed for the determination of a novel non-benzodiazepine anxiolytic (I) ...(R)-2-(methoxymethyl)-1-(7-oxo-8-phenyl-7H-thieno2,3-aquinolizin+ ++- 10-yl)carbonylpyrrolidine and its O-demethyl metabolite (II) in plasma, using column-switching for direct injection of plasma samples. After dilution in internal standard solution, the sample was injected onto a pre-column (17 mm x 4.6 mm) dry-packed with pellicular C18 reversed-phase material. Polar plasma components were removed by flushing the pre-column with water-acetonitrile (90:10, v/v). Retained substances, including I and II, were backflushed onto an analytical column, separated by gradient elution and detected by means of fluorescence detection (excitation, 304 nm; emission, 475 nm). After washing the analytical column and re-equilibrating the pre-column, the system was ready for the next injection. The limit of quantification for I and II was 0.25 and 0.5 ng/ml, respectively, using a 350-microliter specimen of plasma. The practicability of the new method was demonstrated by analysis of more than 300 plasma samples from a tolerance study performed with human volunteers. Owing to its high sensitivity, the method can be used to calculate pharmacokinetic parameters of compounds I and II in man after a single oral dose of about 1 mg of I.
The hemodynamic and clinical data of 42 patients with chronic significant aortic regurgitation and 31 normal subjects were examined. Of the patients with aortic regurgitation, 28 had a third heart ...sound (S3) gallop and 14 did not. There was no significant difference in the severity of regurgitation between the patients with or without an S3 gallop. However, all patients with an S3 gallop had an abnormality increased left ventricular residual volume and depressed contractile state. These findings were supported by the hemodynamic data of two patients who underwent cardiac catheterization before and after the development of an S3 gallop. We conclude that the S3 gallop in patients with chronic AR reflects left ventricular dysfunction, rather than more severe degrees of regurgitation per se, and may therefore be useful for selecting patients for cardiac catheterization and consideration for prosthetic aortic valve replacement.
A sensitive and selective HPLC-column switching method with single quadrupole mass spectrometric detection was developed for the simultaneous determination of the oral platelet aggregation inhibitor ...Sibrafiban
® (double protected prodrug), its prodrug and the active metabolite in rat, dog, and human plasma. The three analytes together with their tri-deuterated internal standards were isolated from plasma by protein precipitation (0.5 M perchloric acid). The de-proteinated samples were injected onto a standard-bore trapping column (4.0 mm i.d., LC-ABZ) of an HPLC-column switching system. Polar plasma components were removed by flushing the trapping column with ammonium formate (pH 3.6; 5 mM). Enriched compounds (including the analytes of interest) were backflushed onto a narrow-bore analytical column (2.1 mm i.d., Inertsil ODS-2) and separated by gradient elution (formic acid/methanol). The whole effluent (200 μl/min) from the analytical column was passed to the turbo ion spray interface without splitting. Selected ion monitoring (SIM) was used for mass spectrometric detection. The limit of quantification for all three analytes was 1 ng/ml, using a 250-μl specimen of plasma. The mean precision and inaccuracy for the three analytes in all species were <6 and <5%, respectively. The practicability of the new analytical method was demonstrated by the analysis of about 500 rat and dog plasma and about 14 000 human plasma samples. The new method represents a successful example for the application of LC single MS with ionspray ionisation to the analysis of small molecule drugs in biological matrices from toxicokinetic studies and large clinical trials.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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