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Abstract Background Anastomotic leakage is the most important surgical complication following esophagectomy. A major cause of leakage is ischemia of the gastric tube that is used for reconstruction of the gastrointestinal tract. Generalized cardiovascular disease, expressed by calcifications of the aorta and celiac axis stenosis on a pre-operative CT scan, is associated with an increased risk of anastomotic leakage. Laparoscopic ischemic conditioning (ISCON) aims to redistribute blood flow and increase perfusion at the anastomotic site by occluding the left gastric, left gastroepiploic and short gastric arteries prior to esophagectomy. This study aims to assess the safety and feasibility of laparoscopic ISCON in selected patients with esophageal cancer and concomitant arterial calcifications. Methods In this prospective single-arm safety and feasibility trial based upon the IDEAL recommendations for surgical innovation, a total of 20 patients will be included recruited in 2 European high-volume centers for esophageal cancer surgery. Patients with resectable esophageal carcinoma (cT1-4a, N0–3, M0) with “major calcifications” of the thoracic aorta accordingly to the Uniform Calcification Score (UCS) or a stenosis of the celiac axis accordingly to the modified North American Symptomatic Carotid Endarterectomy Trial (NASCET) score on preoperative CT scan, who are planned to undergo esophagectomy are eligible for inclusion. The primary outcome variables are complications grade 2 and higher (Clavien-Dindo classification) occurring during or after laparoscopic ISCON and before esophagectomy. Secondary outcomes include intra- and postoperative complications of esophagectomy and the induction of angiogenesis by biomarkers of microcirculation and redistribution of blood flow by measurement of indocyanine green (ICG) fluorescence angiography. Discussion We hypothesize that in selected patients with impaired vascularization of the gastric tube, laparoscopic ISCON is feasible and can be safely performed 12–18 days prior to esophagectomy. Depending on the results, a randomized controlled trial will be needed to investigate whether ISCON leads to a lower percentage and less severe course of anastomotic leakage in selected patients. Trial registration Clinicaltrials.gov, NCT03896399 . Registered 4 January 2019.

Atmospheric aerosols modify the radiative budget of the Earth due to their optical, microphysical and chemical properties, and are considered one of the most uncertain climate forcing agents. In order to characterise the uncertainties associated with satellite and modelling approaches to represent aerosol optical properties, mainly aerosol optical depth (AOD) and Ångström exponent (AE), their representation by different remote-sensing sensors and regional online coupled chemistry–climate models over Europe are evaluated. This work also characterises whether the inclusion of aerosol–radiation (ARI) or/and aerosol–cloud interactions (ACI) help improve the skills of modelling outputs.Two case studies were selected within the EuMetChem COST Action ES1004 framework when important aerosol episodes in 2010 all over Europe took place: a Russian wildfire episode and a Saharan desert dust outbreak that covered most of the Mediterranean Sea. The model data came from different regional air-quality–climate simulations performed by working group 2 of EuMetChem, which differed according to whether ARI or ACI was included or not. The remote-sensing data came from three different sensors: MODIS, OMI and SeaWIFS. The evaluation used classical statistical metrics to first compare satellite data versus the ground-based instrument network (AERONET) and then to evaluate model versus the observational data (both satellite and ground-based data).Regarding the uncertainty in the satellite representation of AOD, MODIS presented the best agreement with the AERONET observations compared to other satellite AOD observations. The differences found between remote-sensing sensors highlighted the uncertainty in the observations, which have to be taken into account when evaluating models. When modelling results were considered, a common trend for underestimating high AOD levels was observed. For the AE, models tended to underestimate its variability, except when considering a sectional approach in the aerosol representation. The modelling results showed better skills when ARI+ACI interactions were included; hence this improvement in the representation of AOD (above 30 % in the model error) and AE (between 20 and 75 %) is important to provide a better description of aerosol–radiation–cloud interactions in regional climate models.

The heterogeneous hydrolysis of N2O5 on the surface of deliquescent aerosol leads to HNO3 formation and acts as a major sink of NOx in the atmosphere during night-time. The reaction constant of this heterogeneous hydrolysis is determined by temperature (T), relative humidity (RH), aerosol particle composition, and the surface area concentration (S). However, these parameters were not comprehensively considered in the parameterization of the heterogeneous hydrolysis of N2O5 in previous mass-based 3-D aerosol modelling studies. In this investigation, we propose a sophisticated parameterization (NewN2O5) of N2O5 heterogeneous hydrolysis with respect to T, RH, aerosol particle compositions, and S based on laboratory experiments. We evaluated closure between NewN2O5 and a state-of-the-art parameterization based on a sectional aerosol treatment. The comparison showed a good linear relationship (R = 0.91) between these two parameterizations. NewN2O5 was incorporated into a 3-D fully online coupled model, COSMO–MUSCAT, with the mass-based aerosol treatment. As a case study, we used the data from the HOPE Melpitz campaign (10–25 September 2013) to validate model performance. Here, we investigated the improvement of nitrate prediction over western and central Europe. The modelled particulate nitrate mass concentrations ([NO3−]) were validated by filter measurements over Germany (Neuglobsow, Schmücke, Zingst, and Melpitz). The modelled [NO3−] was significantly overestimated for this period by a factor of 5–19, with the corrected NH3 emissions (reduced by 50 %) and the original parameterization of N2O5 heterogeneous hydrolysis. The NewN2O5 significantly reduces the overestimation of [NO3−] by ∼ 35 %. Particularly, the overestimation factor was reduced to approximately 1.4 in our case study (12, 17–18 and 25 September 2013) when [NO3−] was dominated by local chemical formations. In our case, the suppression of organic coating was negligible over western and central Europe, with an influence on [NO3−] of less than 2 % on average and 20 % at the most significant moment. To obtain a significant impact of the organic coating effect, N2O5, SOA, and NH3 need to be present when RH is high and T is low. However, those conditions were rarely fulfilled simultaneously over western and central Europe. Hence, the organic coating effect on the reaction probability of N2O5 may not be as significant as expected over western and central Europe.

The climate effect of atmospheric aerosols is associated with their influence on the radiative budget of the Earth due to the direct aerosol–radiation interactions (ARIs) and indirect effects, resulting from aerosol–cloud–radiation interactions (ACIs). Online coupled meteorology–chemistry models permit the description of these effects on the basis of simulated atmospheric aerosol concentrations, although there is still some uncertainty associated with the use of these models. Thus, the objective of this work is to assess whether the inclusion of atmospheric aerosol radiative feedbacks of an ensemble of online coupled models improves the simulation results for maximum, mean and minimum temperature at 2 m over Europe. The evaluated models outputs originate from EuMetChem COST Action ES1004 simulations for Europe, differing in the inclusion (or omission) of ARI and ACI in the various models. The cases studies cover two important atmospheric aerosol episodes over Europe in the year 2010: (i) a heat wave event and a forest fire episode (July–August 2010) and (ii) a more humid episode including a Saharan desert dust outbreak in October 2010. The simulation results are evaluated against observational data from the E-OBS gridded database. The results indicate that, although there is only a slight improvement in the bias of the simulation results when including the radiative feedbacks, the spatiotemporal variability and correlation coefficients are improved for the cases under study when atmospheric aerosol radiative effects are included.

Neumayer was a prominent figure in the development of geophysics in the 19th century from a scientific as well as from an organisational point of view. In this paper we review and highlight his activities and efforts in geomagnetic research within five different aspects of geomagnetism: regional geomagnetic surveys, geomagnetic work in German naval observatories, geomagnetic investigations during the First Polar Year 1882/83, modifications of the Gaussian theory, and geomagnetic charts. In each field Neumayer was a researcher, a thinker, and a stimulating coordinator.

The development of the great aurora of 18 January 1770 has been discussed in fundamental papers by Silberschlag, Behn and other authors. The aurora was observed in middle and low latitudes and in Northern latitude. In Central Europe it displayed all typical auroral forms, including the corona.

On the basis of the analysis of the data of auroral observations at middle latitudes during low solar activity, and modern spectrophotometric research, the feasibility of their joint use for the estimation of the level of the solar activity during periods without instrumental measurements is discussed. In this paper an attempt is undertaken to determine quantitative information on solar activity by comparing the data of visual auroral observations with the modern parameter of their luminescence.

Una revisión de las mínimas de actividad solar y la relación entre la actividad auroral y geomagnética nos permiten establecer que la actividad mínima solar no es evidente en los datos disponibles. doi: https://doi.org/10.22201/igeof.00167169p.1999.38.3.382

A review of solar activity minima and the relationship of the auroral and geomagnetic activities suggest that solar minima are not evident in the available data.

El desarrollo de la gran aurora del 18 de enero de 1770 ha sido discutida en un artículo fundamental por Silberschlag y otros autores. La aurora fue observada en latitudes medias y bajas, y por supuesto en latitudes altas. En Europa central ésta presentó todas las formas típicas de aurora, incluyendo la Corona. Basados en los viejos escritos originales, se recrea el desarrollo de esta aurora. doi: https://doi.org/10.22201/igeof.00167169p.2010.49.3.112

Es werden einige notwendige Ergänzungen zum Problemkreis Meteorologie als physikalische Wissenschaft gegeben.

Gemäß der Ertelschen potentiellen Vorticity definieren die thermodynamischen Variablen in der Zustandsgleichung für Gase die Kräfte, welche die Wirbel räumlich und zeitlich ändern.

It is shown that such data that exist on auroral activity in the period between 1450 and 1550 do not provide conclusive evidence that some authors have claimed for the existence of the so-called "Spörer minimum" in solar activity during this interval.

Der Artikel behandelt Verfahren für die weitgehende Zusammenfassung von Umweltdaten sowie die Kartierung der von ihnen abgebildeten räumlichen und zeitlichen Differenzierungen. Als Beispiel dienen Daten über die 1990, 1995 und 2000 gemessene Akkumulation von As, Cd, Cr, Cu, Fe, Hg. Ni, Pb, Sb, Ti, V, Zn in Moosen an bis zu 1028 Standorten in Deutschland. Die Fülle der Messdaten wird stufenweise komprimiert: Die stoffliche Differenzierung wird durch einen nominal und einen ordinal skalierten Index reduziert. Die beiden Indizes integrieren die aus den Messdaten aller Metalle berechneten Flächeninformationen. Die räumlichen Trends werden auf die Klassen einer landschaftsökologischen Raumgliederung reduziert. Die Lokalisierung von Hot Spots der Metallakkumulation bietet Ansatzpunkte für eine Optimierung des Moos-Monitoring-Messnetzes 2005.

La région vulvaire de l'aulacodine change périodiquement de forme et d'aspect. Les critères d'évaluation sont la largeur de l'ouverture formée par les lèvres, l'enflement, la couleur et l'humectage. L'inspection est facile et rapide en soulevant l'animal par la queue sans que les pattes antérieures ne quittent entièrement le sol. Les changements que l'on peut prendre pour des "signes de chaleur" ne sont pas liés à une meilleure réceptivité, et les mâles ne s'intéressent pas plus aux femelles au vagin "ouvert" qu'aux autres. L'ouverture persiste entre moins de 4 et plus de 28 heures, et l'intervalle entre deux phases d'ouverture varie entre quelques jours et plusieurs semaines. Que ces phénomènes soient liés ou non au cycle sexuel, la détection des chaleurs de l'aulacodine dans le but d'organiser les accouplements n'est pas praticable, et il faut choisir la cohabitation non suivie en groupe polygame

It is shown that such data that exist on auroral activity in the period between 1450 and 1550 do not provide conclusive evidence that some authors have claimed for the existence of the so-called "Spörer minimum" in solar activity during this interval.