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VERITAS and Fermi-LAT Observations of TeV Gamma-Ray Sources Discovered by HAWC in the 2HWC Catalog
(2018)
The High Altitude Water Cherenkov (HAWC) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; >100 GeV) gamma-ray sources based on 507 days of observation. Among these, 19 sources are not associated with previously known teraelectronvolt (TeV) gamma-ray sources. We have studied 14 of these sources without known counterparts with VERITAS and Fermi-LAT. VERITAS detected weak gamma-ray emission in the 1 TeV-30 TeV band in the region of DA 495, a pulsar wind nebula coinciding with 2HWC J1953+294, confirming the discovery of the source by HAWC. We did not find any counterpart for the selected 14 new HAWC sources from our analysis of Fermi-LAT data for energies higher than 10 GeV. During the search, we detected gigaelectronvolt (GeV) gamma-ray emission coincident with a known TeV pulsar wind nebula, SNR G54.1+0.3 (VER J1930+188), and a 2HWC source, 2HWC J1930+188. The fluxes for isolated, steady sources in the 2HWC catalog are generally in good agreement with those measured by imaging atmospheric Cherenkov telescopes. However, the VERITAS fluxes for SNR G54.1+0.3, DA 495, and TeV J2032+4130 are lower than those measured by HAWC, and several new HAWC sources are not detected by VERITAS. This is likely due to a change in spectral shape, source extension, or the influence of diffuse emission in the source region.
The meadow grasshopper, Chorthippus parallelus (Zetterstedt), is common and widespread in Central Europe, with a low dispersal range per generation. A population study in Central Germany (Frankenwald and Thuringer Schiefergebirge) showed strong interpopulation differences in abundance and individual fitness. We examined genetic variability using microsatellite markers within and between 22 populations in a short-to long-distance sampling (19 populations, Frankenwald, Schiefergebirge, as well as a southern transect), and in the Erzgebirge region (three populations), with the latter aiming to check for effects as a result of historical forest cover. Of the 671 C. parallelus captured, none was macropterous (functionally winged). All populations showed a high level of expected and observed heterozygosity (mean 0.80-0.90 and 0.60-0.75, respectively), whereas there was evidence of inbreeding (F(IS) values all positive). Allelic richness for all locus-population combinations was high (mean 9.3-11.2), whereas alleles per locus ranged from 15-62. At a local level, genic and genotypic differences were significant. Pairwise F(ST) values were in the range 0.00-0.04, indicating little interpopulation genetic differentiation. Similarly, the calculated gene flow was very high, based on the respective F(ST) (19.5) and using private alleles (7.7). A Neighbour-joining tree using Nei's D(A) and principal coordinate analysis separated two populations that were collected in the Erzgebirge region. Populations from this region may have escaped the effects of the historical forest cover. The visualization of the spatial arrangement of genotypes revealed one geographical barrier to gene flow in the short-distance sampling.
We isolated and characterized 16 new di- and tetranudeotide microsatellite markers for the critically endangered Asian box turtle genus Cuora, focusing on the "Cuora trifasciata" species complex. The new markers were then used to analyse genetic variability and divergence amongst five described species within this complex, namely C. aurocapitata (n = 18), C. cyclornata (n = 31), C. pani (n = 6), C. trifasciata (n = 58), and C. zhoui (n = 7). Our results support the view that all five species represent valid taxa. Within two species (C. trifasciata and C. cyclornata), two distinct morphotypes were corroborated by microsatellite divergence. For three individuals, morphologically identified as being of hybrid origin, the hybrid status was confirmed by our genetic analysis. Our results confirm the controversial species (Cuora aurocapitata, C. cyclornata) and subspecies/morphotypes (C. cyclornata meieri, C. trifasciata cf. trifasciata) to be genetically distinct, which has critical implications for conservation strategies.
Tyrant flycatchers (Aves: Tyrannidae) are endemic to the New World, and many species of this group are threatened or near-threatened at the global level. The aim of this study was to test the 18 microsatellite markers that have been published for other Tyrant flycatchers in the Strange-tailed Tyrant (Alectrurus risora) and the Sharp-tailed Tyrant (Culicivora caudacuta), two endemic species of southern South American grasslands that are classified as vulnerable. We also analyzed the usefulness of loci in relation to phylogenetic distance to the source species. Amplification success was high in both species (77 to 83%) and did not differ between the more closely and more distantly related species to the source species. Polymorphism success was also similar for both species, with 9 and 8 loci being polymorphic, respectively. An increased phylogenetic distance thus does not gradually lead to allelic or locus dropouts, implying that in Tyrant flycatchers, the published loci are useful independent of species relatedness.
Aus dem Inhalt dieser Ausgabe: BEITRÄGE: Hanna Sonkajärvi: Soldaten als Fremde in Straßburg im 18. Jahrhundert, Jörg Rogge: Das Kriegswesen im späten Mittelalter und seine Erforschung: neuere englische und deutsche Arbeiten zu Krieg, Staat und Gesellschaft, PROJEKTE: Shin Demura: Allso hiebe der innere krieg schon an, der vil Erger dann der eüssere war : die Stadt als Zufluchtsort für Flüchtlinge : Erfahrungsformen des Dreißigjährigen Krieges in der Reichsstadt Ulm und ihrer Region, Robby Fichte: Zur Entwicklungsgeschichte des öffentlich-rechtlichen Vertrages anhand der Begründung des Militärdienstverhältnisses 1650-1914, Urte Christine Allkämper: Die Braut des Soldaten : symbolische Kommunikation mit der Waffe von der Frühen Neuzeit bis zur Gegenwart, Anuschka Tischer: Offizielle Kriegsbegründungen in der frühen Neuzeit - Funktionen, Formen, Inhalte, Thomas Wollschläger: Die Military Revolution und der deutsche Territorialstaat unter besonderer Berücksichtigung Brandenburg-Preußens und Sachsens : Determinanten der Staatskonsolidierung im europäischen Kontext 1670-1740, BERICHTE: Reiner Prass: Tagungsbericht Gewalt in der Frühen Neuzeit : 5. Tagung der Arbeitsgemeinschaft Frühe Neuzeit vom 18. bis 20. September 2003 an der Freien Universität Berlin, Andreas Helmedach, Thomas Kubetzky, Heidi Mehrkens: Tilly ist nur eine Chiffre, die es aufzulösen gilt ... - Jahrestagung des Arbeitskreises Militärgeschichte: Soldat und Gesellschaft : Biographien und Selbstzeugnisse in der Militärgeschichte 10.-11. Oktober 2003, Thomas Kater: Bericht über die Jahrestagung des Arbeitskreises Historische Friedensforschung : Der Friede ist keine leere Idee ... - Bilder und Vorstellungen vom Frieden im langen 19. Jahrhundert, 31.10. bis 2.11.2003, Stiftung Adam von Trott, Imshausen, Jan Marco Sawilla: Religion und Krieg - Bericht über die Hamburger Gespräche zur Geschichtswissenschaft (V III.) WS 2003/ 2004, Dorit Schneider: Kriegsbegründungen in der Geschichte. Strategien der Legitimierung und Legalisierung militärischer Gewalt - 30.-31.01.2004, Deutscher Bundestag, Berlin, REZENSIONEN: Ellen Ueberschär: Das Strafgericht Gottes : Kriegserfahrungen und Religion im Heiligen Römischen Reich Deutscher Nation im Zeitalter des Dreißigjährigen Krieges, hrsg. von Matthias Asche und Anton Schindling, Münster 2001, Jürgen Angelow: Jutta Nowosadtko: Krieg, Gewalt und Ordnung : Einführung in die Militärgeschichte, Tübingen 2002, Jörg Muth: John A. Lynn: Battle - A History of Combat and Culture from Ancient Greece to Modern Amerika, Boulder 2003, Heinrich Lang: Del Treppo, Mario (H g.): Condottieri e uomini d arme nell Italia del Rinascimento. Acura e con un saggio introduttivo di Mario Del Treppo, Napoli 2001, Stefan Kroll: Jörg Muth, Flucht aus dem militärischen Alltag : Ursachen und individuelle Ausprägung der Desertion in der Armee Friedrichs des Großen. Mit besonderer Berücksichtigung der Infanterie-Regimenter der Potsdamer Garnison, Freiburg i. Br. 2003, ANKÜNDIGUNGEN: Bernhard R. Kroener, Ralf Pröve: Tempi passati! Der Arbeitskreis Militär und Gesellschaft in der Frühen Neuzeit : ein Zwischenbericht nach einem Jahrzehnt, Mitgliederversammlung 2004, AMG-Tagung 2007, Cecilie Hollberg: Glaube & Macht : Sachsen im Europa der Reformationszeit ; die 2. Sächsische Landesausstellung ; die Schlacht bei Mühlberg : Ausgang und Folgen
Using SXRR to probe the nature of discontinuities in SLM additive manufactured inconel 718 specimens
(2020)
The utilization of additive manufacturing (AM) to fabricate robust structural components relies on understanding the nature of internal anomalies or discontinuities, which can compromise the structural integrity. While some discontinuities in AM microstructures stem from similar mechanisms as observed in more traditional processes such as casting, others are unique to the AM process. Discontinuities in AM are challenging to detect, due to their submicron size and orientation dependency. Toward the goal of improving structural integrity, minimizing discontinuities in an AM build requires an understanding of the mechanisms of formation to mitigate their occurrence. This study utilizes various techniques to evaluate the shape, size, nature and distribution of discontinuities in AM Inconel 718, in a non-hot isostatic pressed (HIPed) as-built, non-HIPed and direct age, and HIPed with two step age samples. Non-destructive synchrotron radiation refraction and transmission radiography (SXRR) provides additional information beyond that obtained with destructive optical microscopy. SXRR was able to distinguish between voids, cracks and lack of melt in, due to its sensitivity to the orientation of the discontinuity.
Arousal is one of the dimensions of core affect and frequently used to describe experienced or observed emotional states. While arousal ratings of facial expressions are collected in many studies it is not well understood how arousal is displayed in or interpreted from facial expressions. In the context of socioemotional disorders such as Autism Spectrum Disorder, this poses the question of a differential use of facial information for arousal perception. In this study, we demonstrate how automated face-tracking tools can be used to extract predictors of arousal judgments. We find moderate to strong correlations among all measures of static information on one hand and all measures of dynamic information on the other. Based on these results, we tested two measures, average distance to the neutral face and average facial movement speed, within and between neurotypical individuals (N = 401) and individuals with autism (N = 19). Distance to the neutral face was predictive of arousal in both groups. Lower mean arousal ratings were found for the autistic group, but no difference in correlation of the measures and arousal ratings could be found between groups. Results were replicated in an high autistic traits group. The findings suggest a qualitatively similar perception of arousal for individuals with and without autism. No correlations between valence ratings and any of the measures could be found, emphasizing the specificity of our tested measures. Distance and speed predictors share variability and thus speed should not be discarded as a predictor of arousal ratings.