Navigation systems for approach and landing of VTOL aircraft

The formulation and implementation of navigation systems used for research investigations in the V/STOLAND avionics system are described. The navigation systems prove position and velocity in a cartestian reference frame aligned with the runway. They use filtering techniques to combine the raw position data from navaids (e.g., TACAN, MLS) with data from onboard inertial sensors. The filtering techniques which use both complementary and Kalman filters, are described. The software for the navigation systems is also described

Survey of Human Mitochondrial Diseases Using New Genomic/Proteomic Tools

BACKGROUND. We have constructed Bayesian prior-based, amino-acid sequence profiles for the complete yeast mitochondrial proteome and used them to develop methods for identifying and characterizing the context of protein mutations that give rise to human mitochondrial diseases. (Bayesian priors are conditional probabilities that allow the estimation of the likelihood of an event - such as an amino-acid substitution - on the basis of prior occurrences of similar events.) Because these profiles can assemble sets of taxonomically very diverse homologs, they enable identification of the structurally and/or functionally most critical sites in the proteins on the basis of the degree of sequence conservation. These profiles can also find distant homologs with determined three-dimensional structures that aid in the interpretation of effects of missense mutations. RESULTS. This survey reports such an analysis for 15 missense mutations one insertion and three deletions involved in Leber's hereditary optic neuropathy, Leigh syndrome, mitochondrial neurogastrointestinal encephalomyopathy, Mohr-Tranebjaerg syndrome, iron-storage disorders related to Friedreich's ataxia, and hereditary spastic paraplegia. We present structural correlations for seven of the mutations. CONCLUSIONS. Of the 19 mutations analyzed, 14 involved changes in very highly conserved parts of the affected proteins. Five out of seven structural correlations provided reasonable explanations for the malfunctions. As additional genetic and structural data become available, this methodology can be extended. It has the potential for assisting in identifying new disease-related genes. Furthermore, profiles with structural homologs can generate mechanistic hypotheses concerning the underlying biochemical processes - and why they break down as a result of the mutations.United States Department of Energy (DE-FG02-98ER62558); National Science Foundation (DBI-9807993

iCrawl: Improving the Freshness of Web Collections by Integrating Social Web and Focused Web Crawling

Researchers in the Digital Humanities and journalists need to monitor, collect and analyze fresh online content regarding current events such as the Ebola outbreak or the Ukraine crisis on demand. However, existing focused crawling approaches only consider topical aspects while ignoring temporal aspects and therefore cannot achieve thematically coherent and fresh Web collections. Especially Social Media provide a rich source of fresh content, which is not used by state-of-the-art focused crawlers. In this paper we address the issues of enabling the collection of fresh and relevant Web and Social Web content for a topic of interest through seamless integration of Web and Social Media in a novel integrated focused crawler. The crawler collects Web and Social Media content in a single system and exploits the stream of fresh Social Media content for guiding the crawler.Comment: Published in the Proceedings of the 15th ACM/IEEE-CS Joint Conference on Digital Libraries 201

QED self-energy contribution to highly-excited atomic states

We present numerical values for the self-energy shifts predicted by QED (Quantum Electrodynamics) for hydrogenlike ions (nuclear charge $60 \le Z \le 110$) with an electron in an $n=3$, 4 or 5 level with high angular momentum ($5/2\le j \le 9/2$). Applications include predictions of precision transition energies and studies of the outer-shell structure of atoms and ions.Comment: 20 pages, 5 figure

The effects of hypoxia on gestational diabetes mellitus in mice

Abstract. Hypoxia and oxygen sensing are mechanisms which play important roles in many physiological processes like the generation of new blood vessels, production of red blood cells, fetal development as well as in pathophysiological processes like chronic renal failure and cancer. Especially since the Nobel Prize in Physiology or Medicine 2019 was awarded to William G. Kaelin, Gregg L. Semenza and Peter J. Ratcliffe working on this specific topic a broader range of people became aware of its importance. (The Nobel Prize in Physiology or Medicine 2019 — Press release n.d.). In terms of pregnancy hypoxia is the most important determining factor when it comes to duration of gestation and the second most important in birth weight (Krampl 2002)(Jensen and Moore 1997). It is estimated that for every 1000m above sea level the average fetal birth weight decreases by 100g (Soria et al. 2013). Gestational diabetes mellitus (GDM) is defined as a state hyperglycaemia of any degree which is first recognized in pregnant women. (Menke, Casagrande, and Cowie 2018). It has a worldwide prevalence ranging from 6.1 to 30% and has lots of short- and long-term consequences like fetal overgrowth and a higher risk of getting the metabolic syndrome in later life of the child. Because of the observed opposing effects of hypoxia and GDM during pregnancy, we investigated whether hypoxia will ameliorate the GDM symptoms in pregnant mice with insulin resistance. To study the effects of hypoxia on GDM in mice, obesity was induced by feeding 4-months-old C57BL/6N dams with an obesogenic diet for 7 weeks before and throughout pregnancy. Mice fed a normal chow (NC) served as control. Animals were bred following an established protocol and were marked at day E 0.5 after mating which was considered as the beginning of pregnancy. The groups were housed either in normoxic conditions (O2 ≈ 21 %) or in normobaric hypoxia (O2 = 15 %, this corresponds to oxygen tension at 2700m altitude) during gestation; mice were sacrificed at E 9.5 (mid pregnancy) as well as in a second experiment with the same setup at E 17.5 (end pregnancy). General measurements of the dams like weight gain or embryo number were taken as well as metabolites from the lipid and glucose metabolism. On expression level was also checked for genes which play a role in hypoxia response or glucose metabolism. Central findings of the present studies were that the obesogenic diet affected the mice which could be shown through many altered parameters in mid- and in late-pregnancy like elevated serum cholesterol levels or liver triglyceride levels as well as increased insulin resistance. Concerning the effect of hypoxia on obesogenic mice a clear compensating effect of the altered parameters in the H/OD group could not be shown in mid- as well as in late-pregnancy. Due to mating problems with the mice during this study in late-pregnancy the group sizes and other parameters were not as consistent as anticipated, this makes comparison and interpretation of the present results more difficult. Part of the experiments should be repeated and further research needs to be done in order to get a better insight in the underlying mechanisms

Quantum Mechanical Three-Body Problem with Short-Range Interactions

We have investigated S-wave bound states composed of three identical bosons interacting via regulated delta function potentials in non-relativistic quantum mechanics. For low-energy systems, these short-range potentials serve as an approximation to the underlying physics, leading to an effective field theory. A method for perturbatively expanding the three-body bound-state equation in inverse powers of the cutoff is developed. This allows us to extract some analytical results concerning the behavior of the system. Further results are obtained by solving the leading order equations numerically to 11 or 12 digits of accuracy. The limit-cycle behavior of the required three-body contact interaction is computed, and the cutoff-independence of bound-state energies is shown. By studying the relationship between the two- and three-body binding energies, we obtain a high accuracy numerical calculation of Efimov's universal function. Equations for the first order corrections, necessary for the study of cutoff dependence, are derived. However, a numerical solution of these equations is not attempted.Comment: 145 pages, latex, 35 figures, Ph.D. thesi

The Effect of Formation Redshifts on the Cluster Mass-Temperature Relation

I employ an ensemble of hydrodynamical simulations and the XSPEC MEKAL emission model to reproduce observable spectral and flux-weighted temperatures for 24 clusters. Each cluster is imaged at 16 points in its history, which allows the investigation of evolutionary effects on the mass-temperature relation. In the zero redshift scaling relations, I find no evidence for a relationship between cluster temperature and formation epoch for those clusters which acquired 75% of their final mass since a redshift of 0.6. This result holds for both observable and intrinsic intracluster medium temperatures, and implies that halo formation epochs are not an important variable in analysis of observable cluster temperature functions.Comment: 6 pages, 3 postscript figures, submitted to MNRAS Letter

Fragment Approach to Constrained Density Functional Theory Calculations using Daubechies Wavelets

In a recent paper we presented a linear scaling Kohn-Sham density functional theory (DFT) code based on Daubechies wavelets, where a minimal set of localized support functions is optimized in situ and therefore adapted to the chemical properties of the molecular system. Thanks to the systematically controllable accuracy of the underlying basis set, this approach is able to provide an optimal contracted basis for a given system: accuracies for ground state energies and atomic forces are of the same quality as an uncontracted, cubic scaling approach. This basis set offers, by construction, a natural subset where the density matrix of the system can be projected. In this paper we demonstrate the flexibility of this minimal basis formalism in providing a basis set that can be reused as-is, i.e. without reoptimization, for charge-constrained DFT calculations within a fragment approach. Support functions, represented in the underlying wavelet grid, of the template fragments are roto-translated with high numerical precision to the required positions and used as projectors for the charge weight function. We demonstrate the interest of this approach to express highly precise and efficient calculations for preparing diabatic states and for the computational setup of systems in complex environments

Lamb Shift of 3P and 4P states and the determination of α\alpha

The fine structure interval of P states in hydrogenlike systems can be determined theoretically with high precision, because the energy levels of P states are only slightly influenced by the structure of the nucleus. Therefore a measurement of the fine structure may serve as an excellent test of QED in bound systems or alternatively as a means of determining the fine structure constant $\alpha$ with very high precision. In this paper an improved analytic calculation of higher-order binding corrections to the one-loop self energy of 3P and 4P states in hydrogen-like systems with low nuclear charge number $Z$ is presented. A comparison of the analytic results to the extrapolated numerical data for high $Z$ ions serves as an independent test of the analytic evaluation. New theoretical values for the Lamb shift of the P states and for the fine structure splittings are given.Comment: 33 pages, LaTeX, 4 tables, 4 figure