Ethylene Response Factor VII Transkriptionsfaktoren steuern die Umformung der Wurzelsystemarchitektur als Antwort auf Hypoxie

Upon flooding, roots are the first organs to encounter oxygen shortage due to decreased gas diffusion and depletion of oxygen by microorganisms in the soil. Root performance is crucial for plant survival during hypoxia. Arabidopsis thaliana, with its intermediate tolerance to flooding, is a well-suited model organism to characterize adaptation to hypoxia at the level of root system architecture and its underlying molecular regulation. This work revealed distinct changes in the root system which are hypothesized to contribute low oxygen stress adaptation. ERFVIIs antagonize hypoxiainduced root bending and enhance lateral and adventitious root elongation highlighting their regulatory role in the developmental reprogramming of the root system. The study further revealed a, yet unknown, ERFVII-independent sensing mechanism for low oxygen.Staunässe und Überflutung führen bei Pflanzen zu Sauerstoffmangel und damit zu einem Verlust der mitochondrialen ATP Bildung. Wurzeln sind die ersten Organe, die dabei Sauerstoffmangel erfahren, weil Gasdiffusion in Wasser vermindert ist und Sauerstoff im Boden durch aerobe Mikroorganismen aufgebraucht wird. Wurzeln sind aber entscheidend für das Überleben der Pflanze bei Hypoxie. Arabidopsis thaliana, mit seiner mittleren Toleranz gegenüber Überflutung, wurde als Modellorganismus gewählt, um Veränderungen der Wurzelarchitektur bei Hypoxie zu untersuchen, und die zugrundeliegenden molekularen Regulationsmechanismen aufzuklären. In dieser Arbeit wurden spezifische Veränderungen der Wurzelarchitektur in Anwort auf und wahrscheinlich in Anpassung an Sauerstoffmangel beschrieben und teilweise mechanistisch aufgeklärt. ERFVIIs fungieren als Gegenspieler zu der durch Hypoxie ausgelösten Krümmung der Wurzel. Gleichzeitig fördern sie das Wachstum von Sekundärwurzeln, was zu einer insgesamt veränderten Wurzelarchitektur führt. Darüber hinaus wurde deutlich, dass es einen bisher unbekannten, ERFVII unabhängigen, Mechanismus zur Wahrnehmung geringer Sauerstoffkonzentration gibt

Voice handicap of laryngectomees with tracheoesophageal speech

The evaluation of diagnostics and therapies includes more and more subjective, i.e. emotional and social aspects. Focussing on the handicap experienced by dysphonic patients, the Voice Handicap Index (VHI) has previously been found to be of significant clinical and scientific value for different voices. In this study the VHI questionnaire was applied to demonstrate the voice handicap of 20 male laryngectomees using tracheoesophageal voice (Provox®), aged 65.5 B 8.7 years. Their VHI was 45.5 B 24.1, which was significantly higher than the score of patients with functional voice disorders, but differed only slightly from patients with organic laryngeal dysphonia. Focussing on individual data, VHI scores ranged from values similar to persons without voice disorder to maximum handicap of 101. Comparing the VHI scores with the laryngectomees’ gradual self-perception of voice disorder severity, no consistent relationship was found. Considering the large interindividual differences, the VHI may serve as a valuable instrument for the assessment of individual interventional needs rather than for the identification of a general laryngectomees’ handicap

First hints of new sensors

A mechanism by which plants detect and respond to oxygen starvation has been known for some years. Three recent papers suggest that we haven’t been seeing the full picture

Automatic detection of sigmatism in children

We propose in this paper an automatic system to detect sigmatism from the speech signal. Sigmatism occurs when the tongue is positioned incorrectly during articulation of sibilant phones like /s / and /z/. For our task we extracted various sets of features from speech: Mel frequency cepstral coefficients, energies in specific bandwidths of the spectral envelope, and the so-called supervectors, which are the parameters of an adapted speaker model. We then trained several classifiers on a speech database of German adults simulating three different types of sigmatism. Recognition results were calculated at a phone, word and speaker level for both the simulated database and for a database of pathological speakers. For the simulated database, we achieved recognition rates of up to 86%, 87 % and 94 % at a phone, word and speaker level. The best classifier was then integrated as part of a Java applet that allows patients to record their own speech, either by pronouncing isolated phones, a specific word or a list of words, and provides them with a feedback whether the sibilant phones are being correctly pronounced

Segmentation of the glottal space from laryngeal images using the watershed transform

The present work describes a new method for the automatic detection of the glottal space from laryngeal images obtained either with high speed or with conventional video cameras attached to a laryngoscope. The detection is based on the combination of several relevant techniques in the field of digital image processing. The image is segmented with a watershed transform followed by a region merging, while the final decision is taken using a simple linear predictor. This scheme has successfully segmented the glottal space in all the test images used. The method presented can be considered a generalist approach for the segmentation of the glottal space because, in contrast with other methods found in literature, this approach does not need either initialization or finding strict environmental conditions extracted from the images to be processed. Therefore, the main advantage is that the user does not have to outline the region of interest with a mouse click. In any case, some a priori knowledge about the glottal space is needed, but this a priori knowledge can be considered weak compared to the environmental conditions fixed in former works

Block-based syntax from context-free grammars

Block-based programming systems employ a jigsaw metaphor to write programs. They are popular in the domain of programming education (e.g., Scratch), but also used as a programming interface for end-users in other disciplines, such as arts, robotics, and configuration management. In particular, block-based environments promise a convenient interface for Domain-Specific Languages (DSLs) for domain experts who might lack a traditional programming education. However, building a block-based environment for a DSL from scratch requires significant effort. This paper presents an approach to engineer block-based language interfaces by reusing existing language artifacts. We present Kogi, a tool for deriving block-based environments from context-free grammars. We identify and define the abstract structure for describing block-based environments. Kogi transforms a context-free grammar into this structure, which then generates a block-based environment based on Google Blockly. The approach is illustrated with four case studies, a DSL for state machines, Sonification Blocks (a DSL for sound synthesis), Pico (a simple programming language), and QL (a DSL for questionnaires). The results show that usable block-based environments can be derived from context-free grammars, and with an order of magnitude reduction in effort

A Sequential Detection Method for Late Auditory Evoked Potentials

This work presents a novel mechanism for detection of late auditory evoked potentials (AEP). AEPs, which are an important diagnostic tool to detect hearing deficiencies, are contained within the electroencephalogram (EEG) at a very low SNR. Our proposed automatic detection of AEPs is based on the Wavelet-Transform of EEG data for feature extraction. Several transform coefficients are then used for a classification by a neural network; its decisions on successive EEG segments are judged by a sequential statistical test. This test stops when a certain confidence is reached to either accept or reject an AEP. Besides providing an objective recognition of AEPs, this procedure can considerably reduce measurement time