University of Konstanz

About: University of Konstanz is a education organization based out in Konstanz, Baden-Württemberg, Germany. It is known for research contribution in the topics: Population & Membrane. The organization has 12115 authors who have published 27401 publications receiving 951162 citations. The organization is also known as: University of Constance & Universität Konstanz.

Proline metabolism and transport in plant development

Abstract: Proline fulfils diverse functions in plants. As amino acid it is a structural component of proteins, but it also plays a role as compatible solute under environmental stress conditions. Proline metabolism involves several subcellular compartments and contributes to the redox balance of the cell. Proline synthesis has been associated with tissues undergoing rapid cell divisions, such as shoot apical meristems, and appears to be involved in floral transition and embryo development. High levels of proline can be found in pollen and seeds, where it serves as compatible solute, protecting cellular structures during dehydration. The proline concentrations of cells, tissues and plant organs are regulated by the interplay of biosynthesis, degradation and intra- as well as intercellular transport processes. Among the proline transport proteins characterized so far, both general amino acid permeases and selective compatible solute transporters were identified, reflecting the versatile role of proline under stress and non-stress situations. The review summarizes our current knowledge on proline metabolism and transport in view of plant development, discussing regulatory aspects such as the influence of metabolites and hormones. Additional information from animals, fungi and bacteria is included, showing similarities and differences to proline metabolism and transport in plants.

KonIQ-10k: An Ecologically Valid Database for Deep Learning of Blind Image Quality Assessment

Abstract: Deep learning methods for image quality assessment (IQA) are limited due to the small size of existing datasets. Extensive datasets require substantial resources both for generating publishable content and annotating it accurately. We present a systematic and scalable approach to creating KonIQ-10k, the largest IQA dataset to date, consisting of 10,073 quality scored images. It is the first in-the-wild database aiming for ecological validity, concerning the authenticity of distortions, the diversity of content, and quality-related indicators. Through the use of crowdsourcing, we obtained 1.2 million reliable quality ratings from 1,459 crowd workers, paving the way for more general IQA models. We propose a novel, deep learning model (KonCept512), to show an excellent generalization beyond the test set (0.921 SROCC), to the current state-of-the-art database LIVE-in-the-Wild (0.825 SROCC). The model derives its core performance from the InceptionResNet architecture, being trained at a higher resolution than previous models ( $512\times 384$ ). Correlation analysis shows that KonCept512 performs similar to having 9 subjective scores for each test image.

Disagreement and concession in disputes: On the context sensitivity of preference structures

Abstract: This article discusses disagreement sequences in German and Anglo-American disputes. It is argued that the context sensitivity of preference for agreement with assessments that Pomerantz 1984 found in her data has to be elaborated and extended. My findings suggest that the preference structure can change once a dissent-turn-sequence has been displayed; in this case, opponents are expected to defend their positions. The reduction of reluctance markers creates a new preference structure which itself has to be accomplished by all participants. Concessions, defined as a participant's agreeing to the central issue after his or her prior disagreement, show reluctance markers which are viewed as indicators of the dispreferred status in other types of talk. Concessions can be distinguished from partially agreeing presequences of dissent turns. Speakers move toward concessions stepwise. Unprepared position shifts can be regarded by the interlocutors as the inability to defend an opinion. Concessions, being an interactional achievement, reframe the dispute. (Conversation analysis, dispute, context studies, expectation management)

Maltose Transport in Escherichia coli K12

Abstract: The kinetic parameters for the maltose transport system in Escherichia coli K12 were determined with maltose and maltotriose as substrates. The system exhibits an apparent Km of 1 muM for maltose and 2 muM for maltotriose. The V of entry was determined as 2.0 and 1.1 nmol substrate/min per 10(8) cells. Mutations in lamB, the structural gene for the receptor protein of phage lambda, increased the Km for maltose transport by a factor of 100-500 without influencing the maximal rate of transport. Maltotriose is no longer transported in these lamB mutants. The maltose-binding protein, an essential component of the maltose transport system, was found to exhibit substrate-dependent fluorescence quenching. This phenomenon was used to determine dissociation constants and to estimate the rate of ligand dissociation. A Kd of 1 muM for maltose and of 0.16 muM for maltotroise was found. From the comparison of the kinetic parameters of transport of maltose and maltotriose in wild-type and lambda-resistant mutants with the binding constants for both sugars to purified maltose-binding protein, we conclude that the lambda receptor facilitates the diffusion of maltose and maltodextrins through the outer membrane.

Dissociation Following Traumatic Stress Etiology and Treatment

Abstract: We postulate that the cascade ''Freeze-Flight-Fight-Fright-Flag-Faint'' is a coherent sequence of six fear responses that escalate as a function of defense possibilities and proximity to danger during life-threat. The actual sequence of trauma-related response dispositions acted out in an extremely dangerous situation therefore depends on the appraisal of the threat by the organism in relation to her/his own power to act (e.g., age and gender) as well as the perceived characteristics of threat and perpetrator. These reaction patterns provide optimal adaption for particular stages of imminence. Subsequent to the traumatic threats, portions of the experience may be replayed. The actual individual cascade of defense stages a survivor has gone through during the traumatic event will repeat itself every time the fear network, which has evolved peritraumatically, is activated again (i.e., through internal or external triggers or, e.g., during exposure therapy).When a parasympathetically dominated ''shut- down'' was the prominent peri-traumatic response during the traumatic incident, comparable dissociative responses may dominate responding to subsequently experienced threat and may also reappear when the traumatic memory is reactivated. Repeated experience of traumatic stress forms a fear network that can become pathologically detached from contextual cues such as time and location of the danger, a condition which manifests itself as posttraumatic stress disorder (PTSD). Intrusions, for example, can therefore be understood as repetitive displays of fragments of the event, which would then, depending on the dominant physiological response during the threat, elicit a corresponding combination of hyperarousal and dissociation. We suggest that trauma treatment must therefore differentiate between patients on two dimensions: those with peritraumatic sympathetic activation versus those who went down the whole defense cascade, which leads to parasympathetic dominance during the trauma and a corresponding replay of physiological and dissociative responding, when reminded. The differential management of dissociative stages (''fright'' and ''faint'') has important treatment implications.