Factoring Continuous Characters Defined on Subgroups of Products of Topological Groups †

This study is on the factorization properties of continuous homomorphisms defined on subgroups (or submonoids) of products of (para)topological groups (or monoids). A typical result is the following one: Let D=∏i∈IDi be a product of paratopological groups, S be a dense subgroup of D, and χ a continuous character of S. Then one can find a finite set E⊂I and continuous characters χi of Di, for i∈E, such that χ=∏i∈Eχi∘piS, where pi:D→Di is the projection.

Factoring Continuous Characters Defined on Subgroups of Products of Topological Groups

We study factorization properties of continuous homomorphisms defined on subgroups (or submonoids) of products of (para)topological groups (or monoids). A typical result is the following one: Let $D=\prod_{i\in I}D_i$ be a product of paratopological groups, $S$ be a dense subgroup of $D$, and $\chi$ a continuous character of $S$. Then one can find a finite set $E\subset I$ and continuous characters $\chi_i$ of $D_i$, for $i\in E$, such that $\chi=\big(\prod_{i\in E} \chi_i\circ p_i\big)\hs1\res\hs1 S$, where $p_i\colon D\to D_i$ is the projection.

StoatyDive: Evaluation and classification of peak profiles for sequencing data

Background The prediction of binding sites (peak-calling) is a common task in the data analysis of methods such as cross-linking immunoprecipitation in combination with high-throughput sequencing (CLIP-Seq). The predicted binding sites are often further analyzed to predict sequence motifs or structure patterns. When looking at a typical result of such high-throughput experiments, the obtained peak profiles differ largely on a genomic level. Thus, a tool is missing that evaluates and classifies the predicted peaks on the basis of their shapes. We hereby present StoatyDive, a tool that can be used to filter for specific peak profile shapes of sequencing data such as CLIP. Findings With StoatyDive we are able to classify peak profile shapes from CLIP-seq data of the histone stem-loop-binding protein (SLBP). We compare the results to existing tools and show that StoatyDive finds more distinct peak shape clusters for CLIP data. Furthermore, we present StoatyDive’s capabilities as a quality control tool and as a filter to pick different shapes based on biological or technical questions for other CLIP data from different RNA binding proteins with different biological functions and numbers of RNA recognition motifs. We finally show that proteins involved in splicing, such as RBM22 and U2AF1, have potentially sharper-shaped peaks than other RNA binding proteins. Conclusion StoatyDive finally fills the demand for a peak shape clustering tool for CLIP-Seq data that fine-tunes downstream analysis steps such as structure or sequence motif predictions and that acts as a quality control.

Bilingualism Enhances Reported Perspective Taking in Men, but Not in Women

Bilingual speakers have often been found to be superior in taking the perspective of another person. Also, females are commonly found to have enhanced perspective taking (PT) abilities compared with males, with male PT being generally more easily affected by external factors. The present study investigated whether bilingualism improves PT in males more strongly than in females. In total, 108 bilingual and 108 matched monolingual adults, with equal numbers of males and females, filled in the PT subscale of the Interpersonal Reactivity index. While monolinguals showed the typical result of females scoring higher on PT than males, scores of male and female bilinguals did not differ, with both bilingual groups scoring as high as female monolinguals. Thus, bilingualism enhanced self-reported PT only in males, suggesting that male PT can be enhanced through socialization.

Polar Mesospheric Summer Echoes (PMSE) during artificial heating

<p>Polar Mesospheric Summer Echoes (PMSE) are regions of enhanced radar backscatter at 80 to 90 km that are assumed to form in the presence of neutral air turbulence and charged ice particles as a result of spatial variations in the electron density. Changes in the electron temperature, as can be generated by the EISCAT heater, influence the electron diffusivity as well as the charging of the ice particles and both are parameters that influence the radar scattering. In many cases, an overshoot effect [1] can be observed when the backscattered power is reduced during heater-on and rises above the initial signal during heater-off. We present observations made on the 11-12 and 15-16 of August 2018 with the EISCAT VHF radar during PMSE conditions. The EISCAT heating facility, operated at 5.423 MHz, was run in identical cycles where the heater was on for 48 seconds and off for 168 seconds. The observations clearly show the overshoot effect, caused by the cyclic heating of PMSE.  The surface charge of the ice particles increases during the heater-on intervals because of the higher electron temperature. As the heater is turned off the electrons are quickly cooled. The dust particles, however, still carry a higher charge, i.e. more electrons, so that the electrons cannot immediately obtain the initial density distribution. The typical result is that the electron density gradients are increased, which in turn lead to increased radar scattering, an overshoot. During the heater off phase, dust and plasma conditions are expected to relax back to undisturbed conditions. A theory was developed by Havnes [1] to explain the overshoot and we use a dusty plasma code [2] based on this theory to calculate the overshoot curves. They agree well with the average of the observational data. There is clear indication that during high precipitation the PMSE cloud is not affected by the heater and accordingly does not show an overshoot effect. </p><p> </p><p>1.     Havnes, O. (2004). Polar Mesospheric Summer Echoes (PMSE) overshoot effect due to cycling of artificial electron heating. Journal of Geophysical Research: Space Physics, 109(A2).</p><p>2.     Biebricher, A., Havnes, O., Hartquist, T. W., & LaHoz, C. (2006). On the influence of plasma absorption by dust on the PMSE overshoot effect. Advances in Space Research, 38(11), 2541-2550.</p>

Refining the Joint 3D Processing of Terrestrial and UAV Images Using Quality Measures

The paper presents an efficient photogrammetric workflow to improve the 3D reconstruction of scenes surveyed by integrating terrestrial and Unmanned Aerial Vehicle (UAV) images. In the last years, the integration of this kind of images has shown clear advantages for the complete and detailed 3D representation of large and complex scenarios. Nevertheless, their photogrammetric integration often raises several issues in the image orientation and dense 3D reconstruction processes. Noisy and erroneous 3D reconstructions are the typical result of inaccurate orientation results. In this work, we propose an automatic filtering procedure which works at the sparse point cloud level and takes advantage of photogrammetric quality features. The filtering step removes low-quality 3D tie points before refining the image orientation in a new adjustment and generating the final dense point cloud. Our method generalizes to many datasets, as it employs statistical analyses of quality feature distributions to identify suitable filtering thresholds. Reported results show the effectiveness and reliability of the method verified using both internal and external quality checks, as well as visual qualitative comparisons. We made the filtering tool publicly available on GitHub.

INFLUENCE OF GEOMETRY RECOVERY ON STRESS STATE OF OPTIMIZED PARTS

This paper discusses the influence of geometry recovery on actual stress fields within load-carrying parts that have to be reconstructed from the resulting surfaces obtained by topology optimization procedures. A typical result of a topology optimization process is a triangulated surface which represents the boundary of the optimized part. In a production environment, this triangulated surface is mostly used to reconstruct a proper CAD model of the optimized part. This process is by far not automated and may require significant skills and efforts. Unfortunately, it also unavoidably introduces variations in the geometry of the optimized part. Although visually these variations might seem to be rather minor, they may very quickly introduce significant stress field variations. These variations may result in harmful locally increased stress levels and even significant stress concentrations. To get more insight into these phenomena, the topology of a quasi-two-dimensional example part is optimized. The resulting geometry is then reconstructed with various levels of precision. For the obtained geometries, the stress fields are studied numerically. It is shown that stress field variations are indeed such that they may influence significantly the probability of fatigue crack initiation and consequently the service life of the part. Obviously, the geometry recovery after topology optimization should be done very carefully, especially if the part will be subject to cyclic loading during operation.

AE event rate characteristics of flawed granite: from damage stress to ultimate failure

SUMMARY Uniaxial compression tests with combined acousto-optical monitoring techniques are conducted on flawed granite specimens, with the aim of investigating the fracture-related acoustic emission (AE) event rate characteristics at the unstable cracking phase in flawed rocks. The interevent time (IET) function F(τ) is adopted to interpret the AE time-series from damage stress (σcd) to ultimate failure, and photographic data are used to evaluate unstable cracking behaviours in flawed granite. The results show that a high AE event rate is always registered but intermittently interrupted by macrofracturing at the unstable cracking phase. The reversed U-shaped curve relation between the AE event rate and the loading time is documented in unstable flawed granite for the first time. The acoustic quiescence has a mechanismic linkage and quantitative correlation with stress drop, and this synchronous acousto-mechanical behaviour is a typical result of the initiation, growth and coalescence of macrocracks initiated from the flaw tips. Moreover, the reactivation and intensification of fracture process zones (FPZs) by increasing loads are the dominant mechanism triggering unstable crack growth in flawed granite.

When Deliberation Produces Persuasion rather than Polarization: Measuring and modeling Small Group Dynamics in a Field Experiment

This article proposes a new statistical method to measure persuasion within small groups, and applies this approach to a large-scale randomized deliberative experiment. The authors define the construct of ‘persuasion’ as a change in the systematic component of an individual's preference, separate from measurement error, that results from exposure to interpersonal interaction. Their method separately measures persuasion in a latent (left–right) preference space and in a topic-specific preference space. The model's functional form accommodates tests of substantive hypotheses found in the small-group literature. The article illustrates the measurement method by examining changes in study participants' views on US fiscal policy resulting from the composition of the small discussion groups to which they were randomly assigned. The results are inconsistent with the ‘law of small-group polarization’, the typical result found in small-group research; instead, the authors observe patterns of latent and policy-specific persuasion consistent with the aspirations of deliberation.

Mongolian Vowel Harmony in a Eurasian Context

The paper discusses the controversy that has arisen concerning the origin and nature of vowel harmony in Mongolian, as well as in a number of other Eurasian languages. In contrast to the conventional understanding according to which Proto-Mongolic had a palatal-velar harmony of the same type as is attested in the Turkic and Uralic languages, it has been claimed recently that the harmony was actually of the tongue root type, involving, in particular, tongue root retraction in the pronunciation of certain vowels. However, while tongue root harmony is indeed prevalent in many modern Mongolic languages, including standard Mongolian, there are several arguments that can be made in support of the conventional reconstruction. There are serious reasons to assume that Mongolic has undergone a process of vowel rotation, which has turned the originally palatal-velar harmony to tongue root harmony. In this process the originally horizontally organized harmonic pairs have become verticalized. A typical result of the verticalization has been the rapid reduction of the original vowel paradigm as well as the development of new palatal vowels to complement the losses.