The average GeV-band Emission from Gamma-Ray Bursts

We analyze the emission in the 0.3-30 GeV energy range of Gamma-Ray Bursts detected with the Fermi Gamma-ray Space Telescope. We concentrate on bursts that were previously only detected with the Gamma-Ray Burst Monitor in the keV energy range. These bursts will then be compared to the bursts that were individually detected with the Large Area Telescope at higher energies. To estimate the emission of faint GRBs we use non-standard analysis methods and sum over many GRBs to find an average signal which is significantly above background level. We use a subsample of 99 GRBs listed in the Burst Catalog from the first two years of observation. Although mostly not individually detectable, the bursts not detected by the Large Area Telescope on average emit a significant flux in the energy range from 0.3 GeV to 30 GeV, but their cumulative energy fluence is only 8% of that of all GRBs. Likewise, the GeV-to-MeV flux ratio is less and the GeV-band spectra are softer. We confirm that the GeV-band emission lasts much longer than the emission found in the keV energy range. The average allsky energy flux from GRBs in the GeV band is 6.4*10^-4 erg cm^-2 yr^-1 or only 4% of the energy flux of cosmic rays above the ankle at 10^18.6 eV.Comment: Astronomy and Astrophysics, version accepted for publicatio

Photon-Photon Interactions via Rydberg Blockade

We develop the theory of light propagation under the conditions of electromagnetically induced transparency in systems involving strongly interacting Rydberg states. Taking into account the quantum nature and the spatial propagation of light, we analyze interactions involving few-photon pulses. We show that this system can be used for the generation of nonclassical states of light including trains of single photons with an avoided volume between them, for implementing photon-photon gates, as well as for studying many-body phenomena with strongly correlated photons

Ozonation as sewage effluent treatment

Pharmaceutical residues are not efficiently removed by current sewage treatment plant (STP) technologies. This allows for the release of pharmaceutical residues into the aquatic environment. Pharmaceuticals and their metabolites are problematic because they are designed to affect biological processes in non-target aquatic species. It is therefore of interest to limit the release of pharmaceutical residues in order to protect the surface water environment. One potential method for the improvement of sewage effluent treatment is ozonation, a technology capable of eliminating pharmaceutical residues. This licentiate thesis aimed to evaluate the biological effects in adult and embryonic zebrafish, Danio rerio, exposed to ozonated effluent at a Swedish municipal STP outfitted with a full scale effluent ozonation step. Reproduction-related endpoints (e.g. fecundity and gonad maturation), behaviour and hepatic gene expression (e.g. vitellogenin) were sampled in fish exposed for 21 days. Responses in fish exposed to ozonated STP effluent diverged from fish exposed to the normal, non-ozonated STP effluent and tap water control. Firstly, they produced twice the amount of fertilized eggs and had a higher degree of gonadal maturation. Secondly, male hepatic vitellogenin gene expression was induced, indicating estrogenicity due to ozonation. Thirdly, fish exposed to the ozonated effluent effluent exhibited a stress-like behaviour. While ozonation has proven to be very efficient in reducing pharmaceutical parent compound concentrations in STP effluents (on average 77% at Knivsta STP), much remains unclear regarding potentially toxic ozonated by-product (OBP) formation. Therefore, the second part of the thesis explored how zebrafish embryotoxicity of three pharmaceuticals of environmental relevance would be modulated by ozonation in a bench-scale ozonation study. Carbamazepine embryotoxicity increased following ozonation, possibly explained by formation of the OBP carbamazepine-epoxide. Furthermore, ozonation of oxazepam seemingly potentiated its anxiolytic mode of action in exposed zebrafish larvae. Diclofenac embryotoxicity was however completely abolished by ozonation. The results presented in this thesis highlight the importance of new chemical and toxicological knowledge regarding the formation of OBPs in post-ozonated effluents

Coherent many-body spin dynamics in a long-range interacting Ising chain

Coherent many-body quantum dynamics lies at the heart of quantum simulation and quantum computation. Both require coherent evolution in the exponentially large Hilbert space of an interacting many-body system. To date, trapped ions have defined the state of the art in terms of achievable coherence times in interacting spin chains. Here, we establish an alternative platform by reporting on the observation of coherent, fully interaction-driven quantum revivals of the magnetization in Rydberg-dressed Ising spin chains of atoms trapped in an optical lattice. We identify partial many-body revivals at up to about ten times the characteristic time scale set by the interactions. At the same time, single-site-resolved correlation measurements link the magnetization dynamics with inter-spin correlations appearing at different distances during the evolution. These results mark an enabling step towards the implementation of Rydberg atom based quantum annealers, quantum simulations of higher dimensional complex magnetic Hamiltonians, and itinerant long-range interacting quantum matter.Comment: 11 pages, 9 figure

Integrating Genetic, Archaeological, and Historical Perspectives on Eastern Central Europe, 400–900 AD: Brief Description of the ERC Synergy Grant – HistoGenes 856453

Few parts of Europe witnessed so many population shifts in a few centuries as the Carpathian Basin in 400–900 CE. In this macro-region along the middle Danube, Pannonians, Romans, Goths, Gepids, Longobards, Avars, Bulgars, Slavs, Franks and many others came and went. This is an intriguing test case for the relationship between ethnic identities constructed in texts, cultural habitus attested in the archaeological record, and genetic profiles that can now be analysed through ancient DNA. What was the impact of migrations and mobility on the population of the East-Central-Europe? Was the late antique population replaced, did it mix with the newcomers, or did its descendants only adopt new cultural styles? To what degree did biological distinctions correspond to the cultural boundaries and/or ethnonyms in the texts? If pursued with methodological caution, this case study will have implications beyond the field. HistoGenes will analyse c. 6,000 samples from graves with cutting edge scientific methods, and contextualize the interpretation of these data in their archaeological and historical setting. The rapid progress of aDNA analysis and of bio-informatics now make such an enterprise viable. However, the methods of historical interpretation have not kept pace. HistoGenes will, for the first time, unite historians, archaeologists, geneticist, anthropologists, and specialists in bio-informatics, isotope analysis and other scientific methods. A wide range of particular historical questions will be addressed from an interdisciplinary perspective, and fundamental theoretical and methodological issues can be explored. HistoGenes will not only advance our knowledge about a key period in European history, but also establish new standards for the historical interpretation of genetic data. The sixyear HistoGenes Synergy Grant was launched on May 1, 2020.- History and genetics: a new approach - The historical problem - A model area for study: the Carpathian Basin in the fifth to ninth centuries - Project design and general goals - Research questions - Project aims -- 1. Tracing the population history of the Carpathian Basin in the fifth and sixth centuries and the degree of continuity of the late Roman population -- 2. Reconstructing the populations of the Avar Empire and the neighboring regions, 568–c. 800 -- 3. Placing the Avar Khaganate in relation to its neighbors and successors -- 4. Small worlds and large realms: focusing on the social structure of the Carpathian Basi

Quantum gas microscopy of Rydberg macrodimers

A microscopic understanding of molecules is essential for many fields of natural sciences but their tiny size hinders direct optical access to their constituents. Rydberg macrodimers - bound states of two highly-excited Rydberg atoms - feature bond lengths easily exceeding optical wavelengths. Here we report on the direct microscopic observation and detailed characterization of such macrodimers in a gas of ultracold atoms in an optical lattice. The size of about 0.7 micrometers, comparable to the size of small bacteria, matches the diagonal distance of the lattice. By exciting pairs in the initial two-dimensional atom array, we resolve more than 50 vibrational resonances. Using our spatially resolved detection, we observe the macrodimers by correlated atom loss and demonstrate control of the molecular alignment by the choice of the vibrational state. Our results allow for precision testing of Rydberg interaction potentials and establish quantum gas microscopy as a powerful new tool for quantum chemistry.Comment: 13 pages, 9 figure

Ureteroscopic and Scanning Electron Microscopical Findings in Ureteral Anastomoses After Segment Resection

In an experimental study on 8 canine ureters, end-to-end anastomoses were performed after segmental resection between 9 and 13 cm, using two different surgical techniques. After 3 months of observation the three-dimensional structure of the anastomosis and the surrounding areas was investigated by ureteroscopy and scanning electron microscopy. 3 types could be differentiated by the morphologic features of the ureteral lumen: normal width, segmental stricture, and circumferential stricture. The results offer a plausible explanation for the occasional discrepancy between histologic findings of relatively normal lumen width, and functional disorders apparently reflecting ureteral stenosis. They further support that excellent functional and morphologic reconstruction can be achieved even under the extreme conditions of 13 cm segmental resection with obligatory anastomosis under tension. The findings connected with dilatations observed distal to the anastomotic site appear rather contradictory, their interpretation is difficult

Game-Theoretic Model of Incentivizing Privacy-Aware Users to Consent to Location Tracking

Nowadays, mobile users have a vast number of applications and services at their disposal. Each of these might impose some privacy threats on users' "Personally Identifiable Information" (PII). Location privacy is a crucial part of PII, and as such, privacy-aware users wish to maximize it. This privacy can be, for instance, threatened by a company, which collects users' traces and shares them with third parties. To maximize their location privacy, users can decide to get offline so that the company cannot localize their devices. The longer a user stays connected to a network, the more services he might receive, but his location privacy decreases. In this paper, we analyze the trade-off between location privacy, the level of services that a user experiences, and the profit of the company. To this end, we formulate a Stackelberg Bayesian game between the User (follower) and the Company (leader). We present theoretical results characterizing the equilibria of the game. To the best of our knowledge, our work is the first to model the economically rational decision-making of the service provider (i.e., the Company) in conjunction with the rational decision-making of users who wish to protect their location privacy. To evaluate the performance of our approach, we have used real-data from a testbed, and we have also shown that the game-theoretic strategy of the Company outperforms non-strategic methods. Finally, we have considered different User privacy types, and have determined the service level that incentivizes the User to stay connected as long as possible.Comment: 8 pages, 7 figures, In Proceedings of 2015 IEEE Trustcom/BigDataSE/ISP

External Validation of the Early Prediction of Functional Outcome After Stroke Prediction Model for Independent Gait at 3 Months After Stroke

INTRODUCTION: The Early Prediction of Functional Outcome after Stroke (EPOS) model for independent gait is a tool to predict between days 2 and 9 poststroke whether patients will regain independent gait 6 months after stroke. External validation of the model is important to determine its clinical applicability and generalizability by testing its performance in an independent cohort. Therefore, this study aimed to perform a temporal and geographical external validation of the EPOS prediction model for independent gait after stroke but with the endpoint being 3 months instead of the original 6 months poststroke. METHODS: Two prospective longitudinal cohort studies consisting of patients with first-ever stroke admitted to a Swiss hospital stroke unit. Sitting balance and strength of the paretic leg were tested at days 1 and 8 post-stroke in Cohort I and at days 3 and 9 in Cohort II. Independent gait was assessed 3 months after symptom onset. The performance of the model in terms of discrimination (area under the receiver operator characteristic (ROC) curve; AUC), classification, and calibration was assessed. RESULTS: In Cohort I [N = 39, median age: 74 years, 33% women, median National Institutes of Health Stroke Scale (NIHSS) 9], the AUC (95% confidence interval (CI)] was 0.675 (0.510, 0.841) on day 1 and 0.921 (0.811, 1.000) on day 8. For Cohort II (N = 78, median age: 69 years, 37% women, median NIHSS 8), this was 0.801 (0.684, 0.918) on day 3 and 0.846 (0.741, 0.951) on day 9. DISCUSSION AND CONCLUSION: External validation of the EPOS prediction model for independent gait 3 months after stroke resulted in an acceptable performance from day 3 onward in mild-to-moderately affected patients with first-ever stroke without severe prestroke disability. The impact of applying this model in clinical practice should be investigated within this subgroup of patients with stroke. To improve the generalizability of patients with recurrent stroke and those with more severe, neurological comorbidities, the performance of the EPOS model within these patients should be determined across different geographical areas