Symbolic Model Checking for Dynamic Epistemic Logic

Dynamic Epistemic Logic (DEL) can model complex information scenarios in a way that appeals to logicians. However, existing DEL implementations are ad-hoc, so we do not know how the framework really performs. For this purpose, we want to hook up with the best available model-checking and SAT techniques in computational logic. We do this by first providing a bridge: a new faithful representation of DEL models as so-called knowledge structures that allow for symbolic model checking. Next, we show that we can now solve well-known benchmark problems in epistemic scenarios much faster than with existing DEL methods. Finally, we show that our method is not just a matter of implementation, but that it raises significant issues about logical representation and update

Systematic tight-binding analysis of ARPES spectra of transition-metal oxides

We have performed systematic tight-binding (TB) analyses of the angle-resolved photoemission spectroscopy (ARPES) spectra of transition-metal (TM) oxides A$M$O$_3$ ($M=$ Ti, V, Mn, and Fe) with the perovskite-type structure and compared the obtained parameters with those obtained from configuration-interaction (CI) cluster-model analyses of photoemission spectra. The values of $\epsilon_d-\epsilon_p$ from ARPES are found to be similar to the charge-transfer energy $\Delta$ from O $2p$ orbitals to empty TM 3d orbitals and much larger than $\Delta-U/2$ ($U$: on-site Coulomb energy) expected for Mott-Hubbard-type compounds including SrVO$_3$. $\epsilon_d-\epsilon_p$ values from {\it ab initio} band-structure calculations show similar behaviors to those from ARPES. The values of the $p-d$ transfer integrals to describe the global electronic structure are found to be similar in all the estimates, whereas additional narrowing beyond the TB description occurs in the ARPES spectra of the $d$ band.Comment: 5 pages, 3 figure

Revealing structural evolution occurring from photo-initiated polymer network formation

Acomplete account of the structural evolution occurring during photopolymerisation is lacking. Here the physical changes occurring on the nanometer scale during photopolymerisation of acrylates are followed over time by FTIR, X-ray reflectometry, AFM, and GISAXS, offering insight into the mechanism by which initial composition influences the final morphology

The prismatic Sigma 3 (10-10) twin bounday in alpha-Al2O3 investigated by density functional theory and transmission electron microscopy

The microscopic structure of a prismatic $\Sigma 3$ $(10\bar{1}0)$ twin boundary in \aal2o3 is characterized theoretically by ab-initio local-density-functional theory, and experimentally by spatial-resolution electron energy-loss spectroscopy in a scanning transmission electron microscope (STEM), measuring energy-loss near-edge structures (ELNES) of the oxygen $K$-ionization edge. Theoretically, two distinct microscopic variants for this twin interface with low interface energies are derived and analysed. Experimentally, it is demonstrated that the spatial and energetical resolutions of present high-performance STEM instruments are insufficient to discriminate the subtle differences of the two proposed interface variants. It is predicted that for the currently developed next generation of analytical electron microscopes the prismatic twin interface will provide a promising benchmark case to demonstrate the achievement of ELNES with spatial resolution of individual atom columns

Rewritable nanoscale oxide photodetector

Nanophotonic devices seek to generate, guide, and/or detect light using structures whose nanoscale dimensions are closely tied to their functionality. Semiconducting nanowires, grown with tailored optoelectronic properties, have been successfully placed into devices for a variety of applications. However, the integration of photonic nanostructures with electronic circuitry has always been one of the most challenging aspects of device development. Here we report the development of rewritable nanoscale photodetectors created at the interface between LaAlO3 and SrTiO3. Nanowire junctions with characteristic dimensions 2-3 nm are created using a reversible AFM writing technique. These nanoscale devices exhibit a remarkably high gain for their size, in part because of the large electric fields produced in the gap region. The photoconductive response is gate-tunable and spans the visible-to-near-infrared regime. The ability to integrate rewritable nanoscale photodetectors with nanowires and transistors in a single materials platform foreshadows new families of integrated optoelectronic devices and applications.Comment: 5 pages, 5 figures. Supplementary Information 7 pages, 9 figure

Widespread fear of dengue transmission but poor practices of dengue prevention : A study in the slums of Delhi, India

Background This study has been conducted to throw light on the knowledge and practices related to dengue fever among the poor population living in Delhi's slums. Materials A household survey was conducted in 2013 among 3,350 households. The households were stratified by a number of variables related to socio-economic status and health events such as hospitalisation. The data collection was completed through face-to-face interviews conducted with the help of 25 field investigators. Results About 8% of the households had at least one diagnosed dengue case. In comparison to the population surveyed, teenagers (15-19 years) and adults (30-34 years) were more affected whereas children under four years of age were underrepresented. Housewives are more affected by dengue (24%) compared to their share of the population surveyed (17%). Despite the fact that 77% of the respondents are worried about mosquitoes, only 43% of them monitor environment to avoid the presence of breeding sites. Conclusion One cannot exclude the possibility that though young children under the age of four years are exposed to the virus, either their cases were asymptomatic or family members infected during this period had potentially more serious symptoms leading to hospitalisation. This result could thus be explained by budget-related health choices made by this population which do not favour small children. Educational programs should target housewives to improve their impact, as they are the ones mostly responsible for water storage and cleanliness of the house and its neighbourhood. Even with a dengue experience and potentially an acute perception of the risk and its factors, a proper management of environmental conditions is lacking. This along with the fact that word-of-mouth is the main source of information quoted should be a message for municipality health workers to give door-to-door information on how to prevent breeding sites and dengue infection