The Beginning of Bedload Movement of Mixtures Investigated as Natural Armoring in Channels

Beginning of bedload transport in channels, whose beds are formed by gravel-sand mixtures, is theoretically and experimentally investigated. In order to make a theoretically approachable treatment to the problem two assumptions are made: 1. the turbulent fluctuations of the bottom shear stress are statistically describable by a Gaussian distribution; 2. a grain starts in motion when the effective (instantaneous) eroding bottom shear stress on a grain exceeds a critical value, which is a function of the grain size and Reynolds number of the grain. On the basis of these assumptions the probability of remaining still (or being eroded) for a certain grain under given hydraulic conditions is calculated (equation 8; this probability is independent of the grain size distribution of the gravel-sand mixture). During the work a feasible way was found to determine the critical shear stress by a basically new method: the average bottom shear stress was defined as equal to the control shear stress, when for the grain in question, the probability for remaining still and being eroded are equal. To supplement and verify the theory, natural armoring of channel bottoms consisting of gravel-sand-mixtures was investigated in the laboratory. On the basis of these experiments the dimension- less critical shear stress can be determined as a function of the Reynolds number of the grains (Fig. 8), and the distribution function of the fluctuation of the bottom shear stress (Fig. 9); in doing so it was confirmed that the distribution function can be approximated by the Gaussian distribution with a standard deviation of σ = 0.57. The laboratory experiments were supplemented by observations in the field

The Beginning of Bedload Movement of Mixtures Investigated as Natural Armoring in Channels

Beginning of bedload transport in channels, whose beds are formed by gravel-sand mixtures, is theoretically and experimentally investigated. In order to make a theoretically approachable treatment to the problem two assumptions are made: 1. the turbulent fluctuations of the bottom shear stress are statistically describable by a Gaussian distribution; 2. a grain starts in motion when the effective (instantaneous) eroding bottom shear stress on a grain exceeds a critical value, which is a function of the grain size and Reynolds number of the grain. On the basis of these assumptions the probability of remaining still (or being eroded) for a certain grain under given hydraulic conditions is calculated (equation 8; this probability is independent of the grain size distribution of the gravel-sand mixture). During the work a feasible way was found to determine the critical shear stress by a basically new method: the average bottom shear stress was defined as equal to the control shear stress, when for the grain in question, the probability for remaining still and being eroded are equal. To supplement and verify the theory, natural armoring of channel bottoms consisting of gravel-sand-mixtures was investigated in the laboratory. On the basis of these experiments the dimension- less critical shear stress can be determined as a function of the Reynolds number of the grains (Fig. 8), and the distribution function of the fluctuation of the bottom shear stress (Fig. 9); in doing so it was confirmed that the distribution function can be approximated by the Gaussian distribution with a standard deviation of σ = 0.57. The laboratory experiments were supplemented by observations in the field

Diffusion in highly turbulent flow through loose rock porous media

CER67-68JG16.September 1967.Prepared for Pittsburgh Plate Glass Industries

Experiments in the laboratory of populism: the 2018 Hungarian election

Parliamentary elections will be held in Hungary on 8 April. Theresa Gessler and Johannes Wachs preview the vote, noting that although the governing Fidesz party has a sizeable polling lead, the contest promises to be closer than the last parliamentary election four years ago

No country for asylum seekers? How short-term exposure to refugees influences attitudes and voting behavior in Hungary

How does exposure to refugees influence political behavior? We present evidence from Hungary, a country with widespread anti-immigration attitudes, that short term exposure during the 2015 refugee crisis predicts anti-refugee voting and sentiment. We code exposure to refugees at the settlement level using reports from state media, an independent online news site, and an online social media aggregator. Settlements through which refugees traveled showed significantly higher anti-refugee voting in a national referendum in 2016. The effect decreases sharply with distance. Using a difference-in-differences model, we find that the far-right opposition gained, while the governing right-wing party lost votes in these settlements in subsequent parliamentary elections. This suggests incumbents are punished by voters skeptical of immigration regardless of their policy position. Survey data supports this finding of a competition among right-wing parties, as individuals in exposed settlements are more fearful of immigrants and support restrictive policies only if they identify as right-wing

A candidate gene for fire blight resistance in Malus × robusta 5 is coding for a CC-NBS-LRR

Fire blight is the most important bacterial disease in apple (Malus ×  domestica) and pear (Pyrus communis) production. Today, the causal bacterium Erwinia amylovora is present in many apple- and pear-growing areas. We investigated the natural resistance of the wild apple Malus ×  robusta 5 against E. amylovora, previously mapped to linkage group 3. With a fine-mapping approach on a population of 2,133 individuals followed by phenotyping of the recombinants from the region of interest, we developed flanking markers useful for marker-assisted selection. Open reading frames were predicted on the sequence of a BAC spanning the resistance locus. One open reading frame coded for a protein belonging to the NBS-LRR family. The in silico investigation of the structure of the candidate resistance gene against fire blight of M. ×  robusta 5, FB_MR5, led us hypothesize the presence of a coiled-coil region followed by an NBS and an LRR-like structure with the consensus ‘LxxLx[IL]xxCxxLxxL'. The function of FB_MR5 was predicted in agreement with the decoy/guard model, that FB_MR5 monitors the transcribed RIN4_MR5, a homolog of RIN4 of Arabidopsis thaliana that could interact with the previously described effector AvrRpt2EA of E. amylovor

A candidate gene for fire blight resistance in Malus × robusta 5 is coding for a CC-NBS-LRR

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)Fire blight is the most important bacterial disease in apple (Malus ×  domestica) and pear (Pyrus communis) production. Today, the causal bacterium Erwinia amylovora is present in many apple- and pear-growing areas. We investigated the natural resistance of the wild apple Malus ×  robusta 5 against E. amylovora, previously mapped to linkage group 3. With a fine-mapping approach on a population of 2,133 individuals followed by phenotyping of the recombinants from the region of interest, we developed flanking markers useful for marker-assisted selection. Open reading frames were predicted on the sequence of a BAC spanning the resistance locus. One open reading frame coded for a protein belonging to the NBS–LRR family. The in silico investigation of the structure of the candidate resistance gene against fire blight of M. ×  robusta 5, FB_MR5, led us hypothesize the presence of a coiled-coil region followed by an NBS and an LRR-like structure with the consensus ‘LxxLx[IL]xxCxxLxxL’. The function of FB_MR5 was predicted in agreement with the decoy/guard model, that FB_MR5 monitors the transcribed RIN4_MR5, a homolog of RIN4 of Arabidopsis thaliana that could interact with the previously described effector AvrRpt2EA of E. amylovora

Impact of weather cues and resource dynamics on mast occurrence in the main forest tree species in Europe

Mast seeding, the synchronised occurrence of large amounts of fruits and seeds at irregular intervals, is a reproductive strategy in many wind-pollinated species. Although a series of studies have investigated mast year (MY) patterns in European forest tree species at the regional scale, there are few recent evaluations at a European scale on the impact of weather variables (weather cues) and resource dynamics on mast behaviour. Thus the main objective of this study is to investigate the impact of specific weather conditions, as environmental drivers for MYs, on resources in Fagus sylvatica L., Quercus petraea (Matt.)Liebl., Quercus robur L., Picea abies (L.) Karst. and Pinus sylvestris L. at a European level and to explore the robustness of the relationships in smaller regions within Europe. Data on seed production originating from the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) were analysed. Three beta regression models were applied to investigate the impact of seasonal weather variables on MY occurrence, as well as the influence of fruiting intensity levels in the years prior to MYs. Resource dynamics are analysed at three different spatial scales (continent, countries and ecoregions). At a European scale, important weather cues for beech MYs were a cold and wet summer two years before a MY, a dry and warm summer one year before a MY and a warm spring in the MY. For spruce, a cold and dry summer two years prior to a MY and a warm and dry summer in the year before the MY showed the strongest associations with the MY. For oak, high spring temperature in the MY was the most important weather cue. For beech and spruce, and to some extent also for oak species, the best fitting models at European scale were well reflected by those found at smaller scales. For pine, best fitting models were highly diverse concerning weather cues. Fruiting levels were high in all species two years before the MY and also high one year before the MY in the oak species and in pine. In beech, fruiting levels one year before the MY were not important and in spruce, they were inconsistent depending on the region. As a consequence, evidence of resource depletion could only be seen in some regions for spruce.publishedVersio

Status of the BELLE II Pixel Detector

The Belle II experiment at the super KEK B-factory (SuperKEKB) in Tsukuba, Japan, has been collecting $e^+e^−$ collision data since March 2019. Operating at a record-breaking luminosity of up to $4.7×10^{34} cm^{−2}s^{−1}$, data corresponding to $424 fb^{−1}$ has since been recorded. The Belle II VerteX Detector (VXD) is central to the Belle II detector and its physics program and plays a crucial role in reconstructing precise primary and decay vertices. It consists of the outer 4-layer Silicon Vertex Detector (SVD) using double sided silicon strips and the inner two-layer PiXel Detector (PXD) based on the Depleted P-channel Field Effect Transistor (DePFET) technology. The PXD DePFET structure combines signal generation and amplification within pixels with a minimum pitch of $(50×55) μm^2$. A high gain and a high signal-to-noise ratio allow thinning the pixels to $75 μm$ while retaining a high pixel hit efficiency of about $99$. As a consequence, also the material budget of the full detector is kept low at $≈0.21$$\frac{X}{X_0}$ per layer in the acceptance region. This also includes contributions from the control, Analog-to-Digital Converter (ADC), and data processing Application Specific Integrated Circuits (ASICs) as well as from cooling and support structures. This article will present the experience gained from four years of operating PXD; the first full scale detector employing the DePFET technology in High Energy Physics. Overall, the PXD has met the expectations. Operating in the intense SuperKEKB environment poses many challenges that will also be discussed. The current PXD system remains incomplete with only 20 out of 40 modules having been installed. A full replacement has been constructed and is currently in its final testing stage before it will be installed into Belle II during the ongoing long shutdown that will last throughout 2023