Search results for "Main"

The Role of Hydrophobic Mismatch on Transmembrane Helix Dimerization in Living Cells

2019

An exploration of digital ride-hailing multisided platforms' market dynamics: empirical evidence from the Uber case study

2020

PurposeThe purpose of this paper is to experiment a dynamic performance management (DPM) approach to explore and assess the business dynamics of digital ride-hailing platforms with a focus on both supply and demand sides, and related interplays.Design/methodology/approachThe research adopts the DPM framework supported by simulation-based experimentations for developing a systemic case interpretation of Uber Inc. and its specific business complexity.FindingsThe emerging scenario analysis reveals that changes in the commission percentage for drivers and cutting prices for customers (car hailers) by competitors have significant impacts on the car-hailing industry.Originality/valueDPM and assoc…

Stimulus Perception in Bacterial Signal-Transducing Histidine Kinases

2006

SUMMARY Two-component signal-transducing systems are ubiquitously distributed communication interfaces in bacteria. They consist of a histidine kinase that senses a specific environmental stimulus and a cognate response regulator that mediates the cellular response, mostly through differential expression of target genes. Histidine kinases are typically transmembrane proteins harboring at least two domains: an input (or sensor) domain and a cytoplasmic transmitter (or kinase) domain. They can be identified and classified by virtue of their conserved cytoplasmic kinase domains. In contrast, the sensor domains are highly variable, reflecting the plethora of different signals and modes of sens…

The C-terminal domain of ParB is critical for dynamic DNA binding and bridging interactions which condense the bacterial centromere

2017

SUMMARYThe ParB protein forms DNA bridging interactions aroundparSto form networks which condense DNA and earmark the bacterial chromosome for segregation. The mechanism underlying the formation of ParB nucleoprotein complexes is unclear. We show here that the central DNA binding domain is essential for anchoring atparS, and that this interaction is not required for DNA condensation. Structural analysis of the C-terminal domain reveals a dimer with a lysine-rich surface that binds DNA non-specifically and is essential for DNA condensationin vitro. Mutation of either the dimerisation or the DNA binding interface eliminates ParB foci formationin vivo. Moreover, the free C-terminal domain can …

Uses of change-over designs and repeated measurements in sensory and consumer studies

1993

Abstract The paper illustrates two statistical methods, the design and analysis of sensory experiments taking into account the effects of serving order and previously assessed treatment and the analysis of experiments with time repeated measurements. Change-over design experiments balance both presentation order and carry-over effects. The proper analysis of variance allows the testing of these effects and the estimation of product means adjusted for carry-over effect. Repeated measurements occur when groups are being compared over time. Either a corrected split-plot or a multivariate analysis of variance (MANOVA) with measurements at different times forming the variable should be adopted t…

Vanillin cell sensor

2007

Our project for iGEM 2006 consisted of designing a cellular vanillin biosensor. We used an EnvZ -E. coli strain as a chassis, and constructed two different devices: a sensor and an actuator, assembled using OmpR-P as a standardised mediator. The sensor device contained a computation- ally designed vanillin receptor and a synthetic two-component signal transduction protein (Trz). The receptor protein was based on a ribose-binding protein as scaffold. The Trz was built by fusion of the periplasmic and transmembrane domains of a Trg protein with an EnvZ kinase domain. When the receptor complex binds Trg, an allosteric motion is propagated to the cyto- plasmic EnvZ kinase domain, resulting in a…

Viral entry, lipid rafts and caveosomes.

2005

Lipid rafts and caveolae are detergent-insoluble plasma membrane microdomains, involved in cellular endocytic processes and signalling. Several viruses, including a human pathogen, echovirus 1, and an extensively studied simian virus 40 utilize these domains for internalization into the host cells. Interaction of viruses with receptors on the cell surface triggers specific conformational changes of the virus particle and can give rise to signalling events, which determine the mechanisms of virus entry. After internalization via cell surface lipid rafts or caveolae, virus-containing vesicles can fuse with caveosomes, pre-existing cytoplasmic organelles, or dock on other intracellular organel…

Children with Down syndrome in Finland and Italy: comparing adaptive behavior and services

2016

Objectives: The aim of this study was to compare a sample of Italian (n = 29) and Finnish children (n = 32) with Down syndrome for possible differences emerging from diverse educational surroundings. Besides the level of adaptive and challenging behaviors, some other issues were compared, including teacher satisfaction. Methods: We used the children’s teachers as informants. They were interviewed using standardized scales. Results: No differences in adaptive behavior or challenging behavior were observed between the samples. All children from the Italian sample were fully included in mainstream classes, while in the Finnish sample, 92% of all the school years were spent in self-contained sp…

Improving Speaker-Independent Lipreading with Domain-Adversarial Training

2017

We present a Lipreading system, i.e. a speech recognition system using only visual features, which uses domain-adversarial training for speaker independence. Domain-adversarial training is integrated into the optimization of a lipreader based on a stack of feedforward and LSTM (Long Short-Term Memory) recurrent neural networks, yielding an end-to-end trainable system which only requires a very small number of frames of untranscribed target data to substantially improve the recognition accuracy on the target speaker. On pairs of different source and target speakers, we achieve a relative accuracy improvement of around 40% with only 15 to 20 seconds of untranscribed target speech data. On mul…

Invisibilization and Silencing as an Ethical and Sociological Challenge

2017

AbstractExcluded and/or marginalized social groups frequently face problems involving representation in the public sphere. Moreover, the very notion of exclusion typically refers to communicatively or discursively produced mechanisms of being considered irrelevant in public processes of communication. Exclusion and marginalization, understood as processes of silencing or invisibilizing social groups, are particularly serious in cases involving social suffering, i.e. socially produced suffering and/or suffering that can be eliminated or alleviated socially. Making silence heard, giving voice to the silenced and bringing the invisibilized back into the public domain are therefore fundamental …