High-resolution polar low winds obtained from unsupervised sar wind retrieval

High-resolution sea surface observations by spaceborne synthetic aperture radar (SAR) instruments are sorely neglected resources for meteorological applications in polar regions. Such radar observations provide information about wind speed and direction based on wind-induced roughness of the sea surface. The increasing coverage of SAR observations in polar regions calls for the development of SAR-specific applications that make use of the full information content of this valuable resource. Here we provide examples of the potential of SAR observations to provide details of the complex, mesoscale wind structure during polar low events, and examine the performance of two current wind retrieval methods. Furthermore, we suggest a new approach towards accurate wind vector retrieval of complex wind fields from SAR observations that does not require a priori wind direction input that the most common retrieval methods are dependent on. This approach has the potential to be particularly beneficial for numerical forecasting of weather systems with strong wind gradients, such as polar lows

Analysis of the housing market in selected regions of the Czech Republic and evaluation of the advantages of investment in owner-occupied housing

Bydlení patří mezi základní lidské potřeby a každý má snahu tuto potřebu uspokojit. Následně se rozhodujeme, co je pro nás výhodnější a jaké bydlení vybrat, zda nájemní, nebo rovnou zvolit vlastní bydlení. Při volbě vlastního bydlení se dále rozhodujeme, jak toto bydlení pořídit. Ne každý si může dovolit zaplatit nemovitost v hotovosti a v tento moment do hry vstupují bankovní instituce, které nám na nemovitost půjčí. Otázkou, zda má smysl vzít si hypotéku, se zabývá tato práce. Každá osoba je zcela individuální a bude záležet na plánech a cílech konkrétní osoby. Obecně se dá říct, že za aktuálních podmínek je pořízení vlastního bydlení i na hypotéku vhodnou variantou, avšak rozdíl oproti nájemnímu bydlení není velký. Zároveň bydlení v nájmu může mít své výhody, a pokud správně nastavíme majetkový plán, může nám pomoci lépe k finanční nezávislosti než vlastnické bydlení.Having a home is one of the most basic human needs and everyone attempts to accommodate this need as well as possible. We consequently decide what approach is most advantageous for our needs - whether to rent a home or whether to buy and own one. If we decide owning a home is the right option, we then have to decide, how to go about purchasing it. Not everyone can afford paying for a property upfront in cash and at that is when banks come into play, lending us money to buy property. This paper focuses on whether having a mortgage is the correct strategy for acquiring a home. This will vary individual to individual based on his or her life goals and other factors. Generally, it can be said that purchasing a home using a mortgage can be advantageous, but the difference between renting and buying on a mortgage might not be that significant. Renting a home does have its own specific advantages, and when one's financial plans are managed correctly, it can be a better option for accomplishing financial independence.

Unravelling the March 1972 northwest Greenland windstorm with high-resolution numerical simulations

Thule Air Base in northwest Greenland experienced an extreme windstorm during the night of 8/9 March 1972. The event is not among official WMO records because the anemometer broke after recording the highest gust of 93 m s−1. A recent study re‐examined the event based on coarse‐resolution reanalyses and observations which, however, did not fully resolve the proposed storm processes. This is the first study that uses high‐resolution numerical simulations to investigate the processes associated with this windstorm. A cold‐frontal inversion and strong flow across the mountain ridge upstream of Thule Air Base (associated with a passing low pressure system) are shown to be key factors for the severe downslope windstorm in the lee of the ridge. It is shown that trapped lee waves occurred during the initial phase of the storm, but did not contribute to the highest wind speeds as proposed in the previous study. It is confirmed that rotor circulations occurred which possibly contributed to the large wind variability and, hence, large differences between individual observation sites. However, no rotors were present at the time of the highest simulated wind speed. Instead, wave breaking above the lee slope is found to indirectly contribute to the wind maxima by facilitating Kelvin–Helmholtz instability at the top of the shooting flow that caused intense wind speed pulsations near the surface. In agreement with the previous study, a corner jet was simulated, however it was not responsible for the strong winds in the vicinity of the air base. Sensitivity experiments showed that the flow field was considerably influenced by the high topography downstream of the air base and that simulations with very thin or no sea ice cover over Baffin Bay resulted in a weaker frontal inversion and up to about 30% lower maximum wind speeds.publishedVersio

Effect of sibship on infant reactions to unequal resource distribution

The ability to behave prosocially is something that develops throughout the course of infancy and childhood just as many other cognitive traits do (Dunn & Munn, 1968). Eventually one will develop enough cognitively to be capable of the various instances of social interactions and evaluations that aid in the development of this behavior. Despite these prosocial traits not being fully developed until an older age it has been found that infants possess the ability to evaluate situations of resource distribution as either prosocial or antisocial as young as 18-months-old (Geraci & Surian, 2011). Research regarding sibling interactions suggests that sibship aids in the ability to behave prosocially (Dunn & Munn, 1986; Fehr et al., 2008; Lamb, 1978). Previous work regarding the response of infants to unequal resource distribution does not often account for the effect that an infant's sibship status has or would have on their ability to react to unequal resource distribution. Studies aimed at assessing sibling interactions in relation to prosocial behavior and development do not often go as far as creating trials to test such behaviors under distributive circumstances. The purpose of this study is to extend upon previous research done by Jordan (2018) to determine how sibship effects an infant's reaction to receivers of unequal resource distribution. Specifically, this study assesses infants reactions to trials involving both animate and inanimate receiving agents of unequal resource distribution and observing the infants looking behaviors to determine preference between the resource rich or the poor receivers

Integrating Engineering Data Systems for NASA Spaceflight Projects

NASA has a large range of custom-built and commercial data systems to support spaceflight programs. Some of the systems are re-used by many programs and projects over time. Management and systems engineering processes require integration of data across many of these systems, a difficult problem given the widely diverse nature of system interfaces and data models. This paper describes an ongoing project to use a central data model with a web services architecture to support the integration and access of linked data across engineering functions for multiple NASA programs. The work involves the implementation of a web service-based middleware system called Data Aggregator to bring together data from a variety of systems to support space exploration. Data Aggregator includes a central data model registry for storing and managing links between the data in disparate systems. Initially developed for NASA's Constellation Program needs, Data Aggregator is currently being repurposed to support the International Space Station Program and new NASA projects with processes that involve significant aggregating and linking of data. This change in user needs led to development of a more streamlined data model registry for Data Aggregator in order to simplify adding new project application data as well as standardization of the Data Aggregator query syntax to facilitate cross-application querying by client applications. This paper documents the approach from a set of stand-alone engineering systems from which data are manually retrieved and integrated, to a web of engineering data systems from which the latest data are automatically retrieved and more quickly and accurately integrated. This paper includes the lessons learned through these efforts, including the design and development of a service-oriented architecture and the evolution of the data model registry approaches as the effort continues to evolve and adapt to support multiple NASA programs and priorities

Imprints, Vol. 2

Imprints is the official publication for Sigma Tau Delta, the honorary English fraternity. The editors welcome creative works submitted by contributors and also publish winners of the annual T. E. Ferguson Writing Contest. Especially welcome are poems, fiction pieces and essays of no more than 5,000 words in length. At this time we would like to express our gratitude to David Whitescarver, Sigma Tau Delta faculty advisor, for his unrelenting optimism and valuable help in the preparation of this journal

Excited States of Nucleic Acids Probed by Proton Relaxation Dispersion NMR Spectroscopy

In this work an improved stable isotope labeling protocol for nucleic acids is introduced. The novel building blocks eliminate/minimize homonuclear 13C and 1H scalar couplings thus allowing proton relaxation dispersion (RD) experiments to report accurately on the chemical exchange of nucleic acids. Using site-specific 2H and 13C labeling, spin topologies are introduced into DNA and RNA that make 1H relaxation dispersion experiments applicable in a straightforward manner. The novel RNA/DNA building blocks were successfully incorporated into two nucleic acids. The A-site RNA was previously shown to undergo a two site exchange process in the micro- to millisecond time regime. Using proton relaxation dispersion experiments the exchange parameters determined earlier could be recapitulated, thus validating the proposed approach. We further investigated the dynamics of the cTAR DNA, a DNA transcript that is involved in the viral replication cycle of HIV-1. Again, an exchange process could be characterized and quantified. This shows the general applicablility of the novel labeling scheme for 1H RD experiments of nucleic acids

Probing RNA dynamics via longitudinal exchange and CPMG relaxation dispersion NMR spectroscopy using a sensitive 13C-methyl label

The refolding kinetics of bistable RNA sequences were studied in unperturbed equilibrium via 13C exchange NMR spectroscopy. For this purpose a straightforward labeling technique was elaborated using a 2′-13C-methoxy uridine modification, which was prepared by a two-step synthesis and introduced into RNA using standard protocols. Using 13C longitudinal exchange NMR spectroscopy the refolding kinetics of a 20 nt bistable RNA were characterized at temperatures between 298 and 310 K, yielding the enthalpy and entropy differences between the conformers at equilibrium and the activation energy of the refolding process. The kinetics of a more stable 32 nt bistable RNA could be analyzed by the same approach at elevated temperatures, i.e. at 314 and 316 K. Finally, the dynamics of a multi-stable RNA able to fold into two hairpin- and a pseudo-knotted conformation was studied by 13C relaxation dispersion NMR spectroscopy

Software for Collaborative Use of Large Interactive Displays

The MERBoard Collaborative Workspace, which is currently being deployed to support the Mars Exploration Rover (MER) Missions, is the first instantiation of a new computing architecture designed to support collaborative and group computing using computing devices situated in NASA mission operations room. It is a software system for generation of large-screen interactive displays by multiple user

Mathematical treatment of adiabatic fast passage pulses for the computation of nuclear spin relaxation rates in proteins with conformational exchange

Although originally designed for broadband inversion and decoupling in NMR spectroscopy, recent methodological developments have introduced adiabatic fast passage (AFP) pulses into the field of protein dynamics. AFP pulses employ a frequency sweep, and have not only superior inversion properties with respect to offset effects, but they are also easily implemented into a pulse sequence. As magnetization is dragged from the +z to the −z direction, Larmor precession is impeded since magnetization becomes spin-locked, which is a potentially useful feature for the investigation of microsecond to millisecond dynamics. A major drawback of these pulses as theoretical prediction is concerned, however, results from their time-dependent offset: simulations of spin density matrices under the influence of a time-dependent Hamiltonian with non-commuting elements are costly in terms of computational time, rendering data analysis impracticable. In this paper we suggest several ways to reduce the computational time without compromising accuracy with respect to effects such as cross-correlated relaxation and modulation of the chemical shift