The Hamburg Tornado (7 June 2016) from the perspective of low-cost high-resolution radar data and weather forecast model

A tornado hit the northeastern suburbs of Hamburg, Germany, on 7 June 2016. It had an estimated strength of upper end F1 on the Fujita scale and was short-lived with an approximate duration of only 13 min and a path length of just about 1.3 km. We demonstrate that such a small-scale, extreme event can be observed and forecasted accurately by a low-cost radar and by an atmospheric model with low computational costs, respectively. Observations from a low-cost single polarized X-band radar covering the urban area of Hamburg with 60 m spatial and 30 s temporal resolution are analyzed with respect to their ability to capture the development as well as the track of the tornado. In contrast to the national C-band radar network, the X-band radar is capable of capturing the hook echo of the tornado as well as the circular pattern in rain rates, because of its higher resolution in space and time. High-resolution forecasts of the tornado event are conducted with the computational efficient Conformal Cubic Atmosphere Model (CCAM) in order to test the capability of predicting the tornado with a lead time of a few hours. A three step downscaling method is used to obtain a spatial resolution of 1 km with initial conditions taken from the NCEP analysis. Calculated severe weather indices clearly indicate a potential for a tornado. CCAM cannot explicitly resolve small scale tornadic features but the model simulates a strong convective cell only a few kilometers apart from the tornadic thunderstorm observed by the radar

How Strong is European Solidarity?

In recent years, a series of crises have hit the European Union (i.e., the Eurozone crisis, the sovereign debt crises, the Great Recession, the refugee crisis, Brexit). Such precarious times have challenged solidarity both between European citizens, as well as between the Member States of the EU. The current paper investigates the degree of European solidarity in the European Union in the light of these developments. The paper describes the preliminary findings of a recent research project conducted on European solidarity. We surveyed citizens of 13 Members States of the EU about their disposition toward (European) solidarity. An upcoming book will offer an elaborate theoretical framework about the existence of European solidarity. Additionally, this book will also presents detailed results from the project and indepth discussion of the findings. However, we decided to publish some of the descriptive results beforehand in the form of this report as the major findings of our study have high public and political relevance. The development of recent crises has been rather fastpaced, and is in contrast with the long wait that comes with the publication of academic texts. So, the latter process hinders the most important information to reach the public and policy makers as soon as possible and this report wishes to remedy it slightly. In Chapter 1, we will elaborate on the conceptual framework of our study. By European solidarity, we understand a form of solidarity expanded beyond one’s own nation state; recipients of solidarity are other EU countries, or citizens living in another EU country. In the first part of Chapter 1, we systematically distinguish between four different domains of European solidarity: (1) Fiscal solidarity, defined as citizens’ willingness to support indebted European countries financially. (2) Welfare state solidarity, defined as citizens’ strong agreement to support those in need - unemployed, sick, and the elderly - regardless of where they live in the EU, and to reduce inequality between rich and poor people in Europe. (3) Territorial solidarity, the willingness to reduce inequality between poor and rich EU countries. (4) Finally, the refugee crisis has raised the question of (4.1) external solidarity, defined as the support for the EU to grant asylum to refugees coming from outside of EU, and (4.2) internal solidarity, defined as a strong agreement with how Member States should share the burden of distributing refugees among themselves. In the second part of Chapter 1, we define different criteria for determining the strength of European solidarity. In Chapters 2 to 5, we will apply the explicated criteria for the existence of European solidarity to each of the four domains of solidarity. By doing so, we can determine the strength of European solidarity in each domain of solidarity. As this report aims at giving a first overview of some of our results, we will apply two of the four theoretically developed criteria of European solidarity to the four domains only and present the corresponding descriptive results. Overall, our analyses reveal some unanticipated findings. Europeans altogether display a notably higher level of solidarity with citizens of other EU countries and EU states than many politicians and social scientists have so far presumed. This especially applies to the support of people in need (welfare state solidarity) and the reduction of wealth inequalities between rich and poor European countries (territorial solidarity), but also to the domain of fiscal solidarity. On top of this, European solidarity turns out to be more established than the global one. However, this optimistic view is not valid for the domain of solidarity with refugees. Whilst citizens of western and southern European countries support both, the acceptance of refugees and the fair distribution of the incurring costs and burdens be-tween European countries, the majority of people in eastern European countries do not share this point of view

How strong is European solidarity?: preliminary results from a survey conducted in 13 member states of the EU

The paper describes the preliminary findings of a recent research project conducted on Euro-pean solidarity. We surveyed citizens of 13 Members States of the EU about their disposition toward (European) solidarity. An upcoming book will offer an elaborate theoretical framework about the existence of European solidarity. Additionally, this book will also presents detailed results from the project and in-depth discussion of the findings. However, we decided to publish some of the descriptive results beforehand in the form of this report as the major findings of our study have high public and political relevance. The development of recent crises has been rather fast-paced, and is in contrast with the long wait that comes with the publication of aca-demic texts. So, the latter process hinders the most important information to reach the public and policy makers as soon as possible and this report wishes to remedy it slightly

Different Requirement for Wnt/β-Catenin Signaling in Limb Regeneration of Larval and Adult Xenopus

BACKGROUND:In limb regeneration of amphibians, the early steps leading to blastema formation are critical for the success of regeneration, and the initiation of regeneration in an adult limb requires the presence of nerves. Xenopus laevis tadpoles can completely regenerate an amputated limb at the early limb bud stage, and the metamorphosed young adult also regenerates a limb by a nerve-dependent process that results in a spike-like structure. Blockage of Wnt/β-catenin signaling inhibits the initiation of tadpole limb regeneration, but it remains unclear whether limb regeneration in young adults also requires Wnt/β-catenin signaling. METHODOLOGY/PRINCIPAL FINDINGS:We expressed heat-shock-inducible (hs) Dkk1, a Wnt antagonist, in transgenic Xenopus to block Wnt/β-catenin signaling during forelimb regeneration in young adults. hsDkk1 did not inhibit limb regeneration in any of the young adult frogs, though it suppressed Wnt-dependent expression of genes (fgf-8 and cyclin D1). When nerve supply to the limbs was partially removed, however, hsDkk1 expression blocked limb regeneration in young adult frogs. Conversely, activation of Wnt/β-catenin signaling by a GSK-3 inhibitor rescued failure of limb-spike regeneration in young adult frogs after total removal of nerve supply. CONCLUSIONS/SIGNIFICANCE:In contrast to its essential role in tadpole limb regeneration, our results suggest that Wnt/β-catenin signaling is not absolutely essential for limb regeneration in young adults. The different requirement for Wnt/β-catenin signaling in tadpoles and young adults appears to be due to the projection of nerve axons into the limb field. Our observations suggest that nerve-derived signals and Wnt/β-catenin signaling have redundant roles in the initiation of limb regeneration. Our results demonstrate for the first time the different mechanisms of limb regeneration initiation in limb buds (tadpoles) and developed limbs (young adults) with reference to nerve-derived signals and Wnt/β-catenin signaling

Mouse models of neurodegenerative disease: preclinical imaging and neurovascular component.

Neurodegenerative diseases represent great challenges for basic science and clinical medicine because of their prevalence, pathologies, lack of mechanism-based treatments, and impacts on individuals. Translational research might contribute to the study of neurodegenerative diseases. The mouse has become a key model for studying disease mechanisms that might recapitulate in part some aspects of the corresponding human diseases. Neurode- generative disorders are very complicated and multifacto- rial. This has to be taken in account when testing drugs. Most of the drugs screening in mice are very di cult to be interpretated and often useless. Mouse models could be condiderated a ‘pathway models’, rather than as models for the whole complicated construct that makes a human disease. Non-invasive in vivo imaging in mice has gained increasing interest in preclinical research in the last years thanks to the availability of high-resolution single-photon emission computed tomography (SPECT), positron emission tomography (PET), high eld Magnetic resonance, Optical Imaging scanners and of highly speci c contrast agents. Behavioral test are useful tool to characterize di erent ani- mal models of neurodegenerative pathology. Furthermore, many authors have observed vascular pathological features associated to the di erent neurodegenerative disorders. Aim of this review is to focus on the di erent existing animal models of neurodegenerative disorders, describe behavioral tests and preclinical imaging techniques used for diagnose and describe the vascular pathological features associated to these diseases

Performance of high-resolution X-band weather radar networks – the PATTERN example

This publication intends to prove that a network of low-cost local area weather radars (LAWR) is a reliable and scientifically valuable complement to nationwide radar networks. A network of four LAWRs has been installed in northern Germany within the framework of the Precipitation and Attenuation Estimates from a High-Resolution Weather Radar Network (PATTERN) project observing precipitation with a temporal resolution of 30 s, a range resolution of 60 m and a sampling resolution of 1 degrees in the azimuthal direction. The network covers an area of 60 km x 80 km. In this paper, algorithms used to obtain undisturbed precipitation fields from raw reflectivity data are described, and their performance is analysed. In order to correct operationally for background noise in reflectivity measurements, noise level estimates from the measured reflectivity field are combined with noise levels from the last 10 time steps. For detection of non-meteorological echoes, two different kinds of clutter algorithms are applied: single-radar algorithms and network-based algorithms. Besides well-established algorithms based on the texture of the logarithmic reflectivity field (TDBZ) or sign changes in the reflectivity gradient (SPIN), the advantage of the unique features of the high temporal and spatial resolution of the network is used for clutter detection. Overall, the network-based clutter algorithm works best with a detection rate of up to 70 %, followed by the classic TDBZ filter using the texture of the logarithmic reflectivity field. A comparison of a reflectivity field from the PATTERN network with the product from a C-band radar operated by the German Meteorological Service indicates high spatial accordance of both systems in the geographical position of the rain event as well as reflectivity maxima. Long-term statistics from May to September 2013 prove very good accordance of the X-band radar of the network with C-band radar, but, especially at the border of precipitation events, higher-resolved X-band radar measurements provide more detailed information on precipitation structure because the 1 km range gate of C-band radars is only partially covered with rain. The standard deviation within a range gate of the C-band radar with a range resolution of 1 km is up to 3 dBZ at the borders of rain events. The probability of detection is at least 90 %, the false alarm ratio less than 10% for both systems. Therefore, a network of high-resolution low-cost LAWRs can give valuable information on the small-scale structure of rain events in areas of special interest, e.g. urban regions, in addition to the nationwide rada

A simple method for attenuation correction in local X-band radar measurements using C-band radar data

This paper presents a novel, simple method to correct reflectivity measurements of weather radars that operate in attenuation-influenced frequency bands using observations from less attenuated radar systems. In recent years radar systems operating in the X-band frequency range have been developed to provide precipitation fields for areas of special interest in high temporal (<= 1min) and spatial (<= 250m) resolution in complement to nationwide radar networks. However, X-band radars are highly influenced by attenuation. C- and S-band radars typically have coarser resolution (250 m(-1) km and 5 min) but are less affected by attenuation. Correcting for attenuation effects in simple (non-Doppler) single-polarized X-band radars remains challenging and is often dependent on restriction parameters, for example, those derived from mountain returns. Therefore, these algorithms are applicable only in limited areas. The method proposed here uses measurements from C-band radars and hence can be applied in all regions covered by nationwide C-(or S-) band radar networks. First, a single scan of X-band radar measurements is used exemplary to identify advantages and disadvantages of the novel algorithm compared to a standard single radar algorithm. The performance of the correction algorithms in different types of precipitation is examined in nine case studies. The proposed method provides very promising results for each type of precipitation. Additionally, it is evaluated in a 5-month comparison with Micro Rain Radar (MRR) observations. The bias between uncorrected X-band radar and MRR data is nearly eliminated by the attenuation correction algorithm, and the RMSE is reduced by 20% while the correlation of; 0.9 between both systems remains nearly constant