367 research outputs found
Rotating Einstein-Yang-Mills Black Holes
We construct rotating hairy black holes in SU(2) Einstein-Yang-Mills theory.
These stationary axially symmetric black holes are asymptotically flat. They
possess non-trivial non-Abelian gauge fields outside their regular event
horizon, and they carry non-Abelian electric charge. In the limit of vanishing
angular momentum, they emerge from the neutral static spherically symmetric
Einstein-Yang-Mills black holes, labelled by the node number of the gauge field
function. With increasing angular momentum and mass, the non-Abelian electric
charge of the solutions increases, but remains finite. The asymptotic expansion
for these black hole solutions includes non-integer powers of the radial
variable.Comment: 63 pages, 10 figure
Dyonic Non-Abelian Black Holes
We study static spherically symmetric dyonic black holes in
Einstein-Yang-Mills-Higgs theory. As for the magnetic non-abelian black holes,
the domain of existence of the dyonic non-abelian black holes is limited with
respect to the horizon radius and the dimensionless coupling constant ,
which is proportional to the ratio of vector meson mass and Planck mass. At a
certain critical value of this coupling constant, , the maximal
horizon radius is attained. We derive analytically a relation between and the charge of the black hole solutions and confirm this relation
numerically. Besides the fundamental dyonic non-abelian black holes, we study
radially excited dyonic non-abelian black holes and globally regular
gravitating dyons.Comment: LaTeX, 22 pages, 16 figures, three figures added, file manipulation
error in previous replac
Metrological framework for passive radiative cooling technologies and development setups for reproducible in-field performance testing
Almost 20 % of the global electricity consumption is caused by cooling systems. As the demand for cooling is expected to grow tenfold by 2050, improving the efficiency of cooling systems plays a critical role in addressing the global climate challenge. Passive Radiative Cooling (PRC) materials, which can dissipate heat into the surrounding as thermal radiation (especially through the atmospheric infrared window between 8 ”m and 13 ”m) have recently emerged. Hence, the project PaRaMetriC (Metrological Framework for Passive Radiative Cooling Technologies) aims to develop a comprehensive metrological framework with standardized performance indicators and testing protocols to enable comparable evaluation of their cooling performance on-site and the determination of potential energy savings that could derive from the deployment of such technologies.
One work package within this project deals with the design of a testing setup and the development of a protocol for determining the figures of merit of candidate PRC materials by in-field measurements with a relative
uncertainty below 10 %. For this purpose, on-site prototype setups are planned to be realized in different climatic regions, e.g. Barcelona (maritime Mediterranean climate), Madrid (continental Mediterranean
climate), Torino (warm temperate climate) and WĂŒrzburg (moderate temperate climate), in order to cover a wide range of environmental conditions. With these prototype setups, measurements will be performed on
candidate benchmark materials. Additionally, the environmental and atmospheric conditions (temperature, solar irradiance, humidity, wind speed, etc.) will be monitored during the measurements using appropriate
sensors. Up to now, the design work has been started. This presentation gives an overview of the PaRaMetriC project and provides an outlook on the aimed future activities
regarding the setup for in-field measurements, including the configuration of the setup (thermal insulation, thermal load, etc.), the selection of appropriate sensors and the implementation of PRC materials. Furthermore, previous work will be presented. So far, first PRC materials with high solar reflectance and high thermal emittance have been prepared. Beside the infrared-optical properties, the thermal conductivity of the prepared layers has also been measured. At these samples, the derived surface temperature has been measured for sky-facing surfaces in dependence on the surrounding conditions. Together with measurements on reference materials, the correlation of the surface temperature with the solar reflectance index (SRI) has been investigated. The SRI value has been determined by measurements of the solar reflectance and thermal emittance of the prepared PRC materials according to ASTM E 1980 - 11. As a preliminary result, a temperature drop below ambient air temperature has been recorded for some prepared PRC materials even during the day in sunshine
Stationary Dyonic Regular and Black Hole Solutions
We consider globally regular and black hole solutions in SU(2)
Einstein-Yang-Mills-Higgs theory, coupled to a dilaton field. The basic
solutions represent magnetic monopoles, monopole-antimonopole systems or black
holes with monopole or dipole hair. When the globally regular solutions carry
additionally electric charge, an angular momentum density results, except in
the simplest spherically symmetric case. We evaluate the global charges of the
solutions and their effective action, and analyze their dependence on the
gravitational coupling strength. We show, that in the presence of a dilaton
field, the black hole solutions satisfy a generalized Smarr type mass formula.Comment: 23 pages, 4 figure
Immune phenotypes and checkpoint molecule expression of clonally expanded lymph node-infiltrating T cells in classical Hodgkin lymphoma
Lymph node-infiltrating T cells have been of particular interest in classical Hodgkin lymphoma (cHL). High rates of complete therapeutic responses to antibody-mediated immune checkpoint blockade, even in relapsed/refractory patients, suggest the existence of a T cell-dominated, antigen-experienced, functionally inhibited and lymphoma-directed immune microenvironment. We asked whether clonally expanded T cells (1) were detectable in cHL lymph nodes, (2) showed characteristic immune phenotypes, and (3) were inhibited by immune checkpoint molecule expression. We applied high-dimensional FACS index sorting and single cell T cell receptor αÎČ sequencing to lymph node-infiltrating T cells from 10 treatment-naĂŻve patients. T cells were predominantly CD4(+) and showed memory differentiation. Expression of classical immune checkpoint molecules (CTLA-4, PD-1, TIM-3) was generally low (<â12.0% of T cells) and not different between CD4(+) and CD8(+) T cells. Degrees of clonal T cell expansion varied between patients (range: 1-18 expanded clones per patient) and was almost exclusively restricted to CD8(+) T cells. Clonally expanded T cells showed non-naĂŻve phenotypes and low checkpoint molecule expression similar to non-expanded T cells. Our data suggest that the therapeutic effects of immune checkpoint blockade require mechanisms in addition to dis-inhibition of pre-existing lymphoma-directed T cell responses. Future studies on immune checkpoint blockade-associated effects will identify molecular T cell targets, address dynamic aspects of cell compositions over time, and extend their focus beyond lymph node-infiltrating T cells
Comparison of Isoscalar Vector Meson Production Cross Sections in Proton-Proton Collisions
The reaction was investigated with the TOF
spectrometer, which is an external experiment at the accelerator COSY
(Forschungszentrum J\"ulich, Germany). Total as well as differential cross
sections were determined at an excess energy of (). Using the total cross section of for the
reaction determined here and existing data for the reaction
, the ratio
turns out to be
significantly larger than expected by the Okubo-Zweig-Iizuka (OZI) rule. The
uncertainty of this ratio is considerably smaller than in previous
determinations. The differential distributions show that the
production is still dominated by S-wave production at this excess energy,
however higher partial waves clearly contribute. A comparison of the measured
angular distributions for production to published distributions for
production at shows that the data are consistent with an
identical production mechanism for both vector mesons
Classical Yang-Mills Black hole hair in anti-de Sitter space
The properties of hairy black holes in EinsteinâYangâMills (EYM) theory are reviewed, focusing on spherically symmetric solutions. In particular, in asymptotically anti-de Sitter space (adS) stable black hole hair is known to exist for frak su(2) EYM. We review recent work in which it is shown that stable hair also exists in frak su(N) EYM for arbitrary N, so that there is no upper limit on how much stable hair a black hole in adS can possess
Worldwide diversity of endophytic fungi and insects associated with dormant tree twigs
International trade in plants and climate change are two of the main factors causing damaging tree pests (i.e. fungi and insects) to spread into new areas. To mitigate these risks, a large-scale assessment of tree-associated fungi and insects is needed. We present records of endophytic fungi and insects in twigs of 17 angiosperm and gymnosperm genera, from 51 locations in 32 countries worldwide. Endophytic fungi were characterized by high-throughput sequencing of 352 samples from 145 tree species in 28 countries. Insects were reared from 227 samples of 109 tree species in 18 countries and sorted into taxonomic orders and feeding guilds. Herbivorous insects were grouped into morphospecies and were identified using molecular and morphological approaches. This dataset reveals the diversity of tree-associated taxa, as it contains 12,721 fungal Amplicon Sequence Variants and 208 herbivorous insect morphospecies, sampled across broad geographic and climatic gradients and for many tree species. This dataset will facilitate applied and fundamental studies on the distribution of fungal endophytes and insects in trees
Forward modeling of collective Thomson scattering for Wendelstein 7-X plasmas: Electrostatic approximation
In this paper, we present a method for numerical computation of collective Thomson scattering (CTS). We developed a forward model, eCTS, in the electrostatic approximation and benchmarked it against a full electromagnetic model. Differences between the electrostatic and the electromagnetic models are discussed. The sensitivity of the results to the ion temperature and the plasma composition is demonstrated. We integrated the model into the Bayesian data analysis framework Minerva and used it for the analysis of noisy synthetic data sets produced by a full electromagnetic model. It is shown that eCTS can be used for the inference of the bulk ion temperature. The model has been used to infer the bulk ion temperature from the first CTS measurements on Wendelstein 7-X
The association between migrant status and transition in an ultra-high risk for psychosis population
Purpose: Migrant status is one of the most replicated and robust risk factors for developing a psychotic disorder. This study aimed to determine whether migrant status in people identified as Ultra-High Risk for Psychosis (UHR) was associated with risk of transitioning to a full-threshold psychotic disorder. Methods: Hazard ratios for the risk of transition were calculated from five large UHR cohorts (n = 2166) and were used to conduct a meta-analysis using the generic inverse-variance method using a random-effects model. Results: 2166 UHR young people, with a mean age of 19.1 years (SD ± 4.5) were included, of whom 221 (10.7%) were first-generation migrants. A total of 357 young people transitioned to psychosis over a median follow-up time of 417 days (I.Q.R.147â756 days), representing 17.0% of the cohort. The risk of transition to a full-threshold disorder was not increased for first-generation migrants, (HR = 1.08, 95% CI 0.62â1.89); however, there was a high level of heterogeneity between studies The hazard ratio for second-generation migrants to transition to a full-threshold psychotic disorder compared to the remainder of the native-born population was 1.03 (95% CI 0.70â1.51). Conclusions: This meta-analysis did not find a statistically significant association between migrant status and an increased risk for transition to a full-threshold psychotic disorder; however, several methodological issues could explain this finding. Further research should focus on examining the risk of specific migrant groups and also ensuring that migrant populations are adequately represented within UHR clinics
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