Pränataldiagnostik

Zusammenfassung: Die vorgeburtliche Ultraschalldiagnostik hat die Schwangerenvorsorge im Verlauf des letzten fünf Jahrzehnte völlig verändert. Ohne Risiken für das Ungeborene können wir heute seine vorgeburtliche Entwicklung überwachen und Risikosituationen für Mutter und Kind sowie fetale Erkrankungszustände erkennen. Daher werden heute allen Schwangeren drei Ultraschallvorsorgeuntersuchungen im Rahmen der Mutterschaftsvorsorge angeboten. Nur eine systematische und strukturierte Untersuchung bietet im Verbund mit einer umfassenden Ausbildung Gewähr, die Möglichkeiten der Technologie für die Schwangere und ihr ungeborenes Kind optimal zu nutzen. Ein adäquat durchgeführtes Ultraschallscreening ermöglicht eine exakte Datierung der Schwangerschaft, erkennt Mehrlingsschwangerschaften eindeutig und erlaubt über die Chorionizitäts- und Amnionizitätsdiagnostik eine Risikoklassifizierung. Ferner kann eine Vielzahl fetaler Erkrankungen und Fehlbildungen sicher diagnostiziert bzw. ausgeschlossen werden. In einigen Fällen ist aufgrund der vorgeburtlichen Diagnose eine gezielte Behandlung möglich, andere Feten profitieren von einem optimierten perinatalen Managemen

Comics and Fictional Conundrums: Art Drawn From and For the Writing Center

Our goal is to inspire other tutors to be more creative in communicating, educating, and enriching the environment of the writing center. We hope other tutors will better internalize theory through art. In her story The Spirit Indeed is Willing , Carrie projected her experience in the writing center into a literary form to better embody the complex relationship between the tutor and student, and to represent heteroglossia in the writing center. Abigail, in writing How to Tutor Reluctant Writers , sought to find a new way to illustrate theories in practice. By embracing the relatively new form of the informal comic, Abigail hopes to make theory more accessible and interesting. We believe our contributions are relevant to this conference because they are artistic renderings, and are by nature innovative. As art pieces, these contributions manifest the theories and practices discussed in writing center discourse

PCR-GLOBWB 2: a 5 arcmin global hydrological and water resources model

We present PCR-GLOBWB 2, a global hydrology and water resources model. Compared to previous versions of PCR-GLOBWB, this version fully integrates water use. Sector-specific water demand, groundwater and surface water withdrawal, water consumption, and return flows are dynamically calculated at every time step and interact directly with the simulated hydrology. PCR-GLOBWB 2 has been fully rewritten in Python and PCRaster Python and has a modular structure, allowing easier replacement, maintenance, and development of model components. PCR-GLOBWB 2 has been implemented at 5 arcmin resolution, but a version parameterized at 30 arcmin resolution is also available. Both versions are available as open-source codes on https://github.com/UU-Hydro/PCR-GLOBWB_model (Sutanudjaja et al., 2017a). PCR-GLOBWB 2 has its own routines for groundwater dynamics and surface water routing. These relatively simple routines can alternatively be replaced by dynamically coupling PCR-GLOBWB 2 to a global two-layer groundwater model and 1-D–2-D hydrodynamic models. Here, we describe the main components of the model, compare results of the 30 and 5 arcmin versions, and evaluate their model performance using Global Runoff Data Centre discharge data. Results show that model performance of the 5 arcmin version is notably better than that of the 30 arcmin version. Furthermore, we compare simulated time series of total water storage (TWS) of the 5 arcmin model with those observed with GRACE, showing similar negative trends in areas of prevalent groundwater depletion. Also, we find that simulated total water withdrawal matches reasonably well with reported water withdrawal from AQUASTAT, while water withdrawal by source and sector provide mixed results

Электрооборудование и электропривод ротора буровой установки

Цель работы - разработка и исследование двухзонного электропривода ротора буровой установки. В работе выбраны элементы силовой цепи, определены оптимальные параметры настройки регуляторов системы, рассчитаны статические и динамические характеристики, определены качественные показатели. В результате исследования установлено, что разработанная система соответствует технологическим и техническим требованиям.The purpose of the work is to develop and study a two-zone electric drive of the drilling rig rotor. In the operation, elements of the power circuit are selected, optimal parameters of system regulators are determined, static and dynamic characteristics are calculated, qualitative indicators are determined. As a result of the study, it was found that the developed system meets the technological and technical requirements

Nonorientable spacetime tunneling

Misner space is generalized to have the nonorientable topology of a Klein bottle, and it is shown that in a classical spacetime with multiply connected space slices having such a topology, closed timelike curves are formed. Different regions on the Klein bottle surface can be distinguished which are separated by apparent horizons fixed at particular values of the two angular variables that eneter the metric. Around the throat of this tunnel (which we denote a Klein bottlehole), the position of these horizons dictates an ordinary and exotic matter distribution such that, in addition to the known diverging lensing action of wormholes, a converging lensing action is also present at the mouths. Associated with this matter distribution, the accelerating version of this Klein bottlehole shows four distinct chronology horizons, each with its own nonchronal region. A calculation of the quantum vacuum fluctuations performed by using the regularized two-point Hadamard function shows that each chronology horizon nests a set of polarized hypersurfaces where the renormalized momentum-energy tensor diverges. This quantum instability can be prevented if we take the accelerating Klein bottlehole to be a generalization of a modified Misner space in which the period of the closed spatial direction is time-dependent. In this case, the nonchronal regions and closed timelike curves cannot exceed a minimum size of the order the Planck scale.Comment: 11 pages, RevTex, Accepted in Phys. Rev.

In Vivo Time- Resolved Microtomography Reveals the Mechanics of the Blowfly Flight Motor

Dipteran flies are amongst the smallest and most agile of flying animals. Their wings are driven indirectly by large power muscles, which cause cyclical deformations of the thorax that are amplified through the intricate wing hinge. Asymmetric flight manoeuvres are controlled by 13 pairs of steering muscles acting directly on the wing articulations. Collectively the steering muscles account for <3% of total flight muscle mass, raising the question of how they can modulate the vastly greater output of the power muscles during manoeuvres. Here we present the results of a synchrotron-based study performing micrometre-resolution, time-resolved microtomography on the 145 Hz wingbeat of blowflies. These data represent the first four-dimensional visualizations of an organism's internal movements on sub-millisecond and micrometre scales. This technique allows us to visualize and measure the three-dimensional movements of five of the largest steering muscles, and to place these in the context of the deforming thoracic mechanism that the muscles actuate. Our visualizations show that the steering muscles operate through a diverse range of nonlinear mechanisms, revealing several unexpected features that could not have been identified using any other technique. The tendons of some steering muscles buckle on every wingbeat to accommodate high amplitude movements of the wing hinge. Other steering muscles absorb kinetic energy from an oscillating control linkage, which rotates at low wingbeat amplitude but translates at high wingbeat amplitude. Kinetic energy is distributed differently in these two modes of oscillation, which may play a role in asymmetric power management during flight control. Structural flexibility is known to be important to the aerodynamic efficiency of insect wings, and to the function of their indirect power muscles. We show that it is integral also to the operation of the steering muscles, and so to the functional flexibility of the insect flight motor