Lensing Signatures of a Slowly-Accelerated Black Hole

Accelerating supermassive black holes, connected to cosmic strings, could contribute to structure formation and get captured by galaxies if their velocities are small. This would mean that the acceleration of these black holes is small too. Such a slow acceleration has no significant effect on the shadow of such supermassive black holes. We also show that, for slowly accelerating black holes, the angular position of images in the gravitational lensing effects do not change significantly. We propose a method to observe the acceleration of these black holes through the gravitational lensing. The method is based on the observation that differential time delays associated with the images are substantially different with respect to the case of non-accelerating black holes. This is in contrast with when the theory governing the strong gravitational field around the black hole is different from general relativity, where not only the differential time delays but the angular position of images would be different. We conclude that, if the observed angular position of images are compatible with the prediction of general relativity, a possible deviation in the differential time delays between the observed values and those predicted by general relativity, could be due to the acceleration of the black hole.Comment: Title changed, 11 pages, 7 figure

Measuring black hole spin through gravitational lensing of pulsars

We put forward a new procedure for measuring the spin of a black hole with unprecedented accuracy based on gravitational lensing of millisecond pulsars. The deflection angle of light increases by increasing the rotation parameter. For primary and secondary images the angular positions are larger for rotating black holes by an amount of the order of microarcseconds. Also, the differential time delay for the case of a rotating black hole is larger than that for the non-rotating case and the difference could be as large as a few seconds. We show that this quantity could help us achieve an extremely precise measurement of the black hole spin, much more accurate than the current and near future achievable estimation of black hole spin through other methods.Comment: 6 pages, 1 figur

Markov Aggregation for Speeding Up Agent-Based Movement Simulations

...In this work, we investigate Markov aggregation for agent-based models (ABMs). Specifically, if the ABM models agent movements on a graph, if its ruleset satisfies certain assumptions, and if the aim is to simulate aggregate statistics such as vertex populations, then the ABM can be replaced by a Markov chain on a comparably small state space. This equivalence between a function of the ABM and a smaller Markov chain allows to reduce the computational complexity of the agent-based simulation from being linear in the number of agents, to being constant in the number of agents and polynomial in the number of locations. We instantiate our theory for a recent ABM for forced migration (Flee).We show that,even though the rulesets of Flee violate some of our necessary assumptions, the aggregated Markov chain-based model,Markov Flee,achieves comparable accuracy at substantially reduced computational cost. Thus, Markov Flee can help NGOs and policy makers forecast forced migration in certain conflict scenarios in a cost-effective manner, contributing to fast and efficient delivery of humanitarian relief.This work has been supported by the HiDALGO, ITFLOWS, SEAVEA ExCALIBUR, and BrAIN projects. The projects HiDALGO (Grant No. 824115) and ITFLOWS (Grant No. 882986) have been funded by the European Commission’s H2020 Programme. The project SEAVEA ExCALIBUR (Grant No. EP/W007711/1) has received funding from EPSRC. The project BrAIN – Brownfield Artificial Intelligence Network for Forging of High Quality Aerospace Components (Grant No. 881039) is funded in the framework of the program “TAKE OFF”, which is a research and technology program of the Austrian Federal Ministry of Transport, Innovation and Technology. The Know-Center is funded within the Austrian COMET Program - Competence Centers for Excellent Technologies - under the auspices of the Austrian Federal Ministry of Climate Action, Environment, Energy, Mobility, Innovation and Technology, the Austrian Federal Ministry of Digital and Economic Affairs, and by the State of Styria. COMET is managed by the Austrian Research Promotion Agency FFG

Analysing the effect of a dynamic physical environment network on the travel dynamics of forcibly displaced persons in Mali

Data Availability Statement: The exact code used for this work is available here: https://github.com/djgroen/flee/tree/pt-accessibility; All input files are available here: https://github.com/djgroen/FabFlee/tree/aed751fd10333ed4394578f48133b6cb0e733242/config_files/mali-freek; Output files can be generated using the code and input files (see https://flee.readthedocs.io for instructions).Supplementary Materials: Electronic Supplementary Material for this paper is available at: https://www.sciltp.com/journals/ijndi/2024/1/348/s1.As of 2023, the world has approximately 100 million refugees, many of whom have been displaced by violent conflicts. Accurately predicting where these people may go can help non-government organisations (NGOs) and other support organisations to more effectively help these refugees. In this paper, we extend the existing flee migration forecasting model which models migration using intelligent agents with a dynamic network that represents the physical environment. In doing so, we integrate time-dependent data into four different characteristics from three public data sources. We obtain data from aspects such as the slope, drainage, soil and infrastructure, and use these aspects to systematically modify the movement preferences of forcibly displaced agents in the flee model. We showcase our approach by applying it to the 2012 northern Mali conflict. We find that numerous routes previously deemed traversable are actually inaccessible for prolonged periods according to sensor data, and a range of off-road routes are instead traversable for vehicles. We also perform a validation comparison with the original modelling approach, and find that our revised representation of travel routes leads to a reduction of 4.5% in the averaged relative difference. Our approach can be reused in other flee conflict contexts, of which five are present in the EU-funded ITFLOWS project alone. Our work provides the ability to represent a dynamic physical environment and potentially improves the simulation accuracy in a range of flee conflict situations.This work was supported by the ITFLOWS project and the HiDALGO project, both of which have received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 882986 and 824115, respectively. In addition, this work was supported by EPSRC under grant agreement EP/W007711/1

Clinical grade human adipose tissue-derived mesenchymal stem cell banking

In this study, our aim was to produce a generation of GMP-grade adipose tissue-derived mesenchymal stem cells for clinical applications. According to our results, we fulfill to establish consistent and also reproducible current good manufacturing practice (cGMP) compliant adipose tissue-derived mesenchymal stem cells from five female donors. The isolated cells were cultured in DMEM supplemented with 10 fetal bovine serum and characterized by standard methods. Moreover, karyotyping was performed to evaluate chromosomal stability. Mean of donors� age was 47.6 ± 8.29 year, mean of cell viability was 95.6 ± 1.51, and cell count was between 9�106 and 14�106 per microliter with the mean of 12.2�106 ± 2863564.21 per microliter. The main aim of this project was demonstrating the feasibility of cGMP-compliant and clinical grade adipose tissue-derived mesenchymal stem cells preparation and banking for clinical cell transplantation trials. © 2015 Tehran University of Medical Sciences. All rights reserved

Clinical Grade Human Adipose Tissue-Derived Mesenchymal Stem Cell Banking

In this study, our aim was to produce a generation of GMP-grade adipose tissue-derived mesenchymal stem cells for clinical applications. According to our results, we fulfill to establish consistent and also reproducible current good manufacturing practice (cGMP) compliant adipose tissue-derived mesenchymal stem cells from five female donors. The isolated cells were cultured in DMEM supplemented with 10 fetal bovine serum and characterized by standard methods. Moreover, karyotyping was performed to evaluate chromosomal stability. Mean of donors' age was 47.6 ± 8.29 year, mean of cell viability was 95.6 ± 1.51, and cell count was between 9�106 and 14�106 per microliter with the mean of 12.2�106 ± 2863564.21 per microliter. The main aim of this project was demonstrating the feasibility of cGMP-compliant and clinical grade adipose tissue-derived mesenchymal stem cells preparation and banking for clinical cell transplantation trials

Genetic Variants of Cytochrome b-245, Alpha Polypeptide Gene and Premature Acute Myocardial Infarction Risk in An Iranian Population

Background: Oxidative stress induced by superoxide anion plays critical roles in the pathogenesis of coronary artery disease (CAD) and hence acute myocardial infarction (AMI). The major source of superoxide production in vascular smooth muscle and endothelial cells is the NADPH oxidase complex. An essential component of this complex is p22phox, that is encoded by the cytochrome b-245, alpha polypeptide (CYBA) gene. The aim of this study was to investigate the association of CYBA variants (rs1049255 and rs4673) and premature acute myocardial infarction risk in an Iranian population. Methods: The study population consisted of 158 patients under the age of 50 years, with a diagnosis of premature AMI, and 168 age-matched controls with normal coronary angiograms. Genotyping of the polymorphisms was performed by the polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Results: There was no association between the genotypes and allele frequencies of rs4673 polymorphism and premature acute myocardial infarction (P>0.05). A significant statistical association was observed between the genotypes distribution of rs1049255 polymorphism and AMI risk (P=0.037). Furthermore, the distribution of AA+AG/GG genotypes was found to be statistically significant between the two groups (P=0.011). Conclusions: Our findings indicated that rs1049255 but not rs4673 polymorphism is associated with premature AMI

Soft Nondamaging Contacts Formed from Eutectic Ga-In for the Accurate Determination of Dielectric Constants of Organic Materials

A method for accurately measuring the relative dielectric constant (εr) of thin films of soft, organic materials is described. The effects of the bombardment of these materials with hot Al atoms, the most commonly used top electrode, are mitigated by using electrodes fabricated from eutectic gallium-indium (EGaIn). The geometry of the electrode is defined by injection into microchannels to form stable structures that are nondamaging and that conform to the topology of the organic thin film. The εr of a series of references and new organic materials, polymers, and fullerene derivatives was derived from impedance spectroscopy measurements for both Al and EGaIn electrodes showing the specific limitations of Al with soft, organic materials and overcoming them with EGaIn to determine their dielectric properties and provide realistic values of εr