Search results for "CHANNELS"
showing 10 items of 411 documents
Unstructural Biology of TRP Ion Channels: The Role of Intrinsically Disordered Regions in Channel Function and Regulation
2021
The first genuine high-resolution single particle cryo-electron microscopy structure of a membrane protein determined was a transient receptor potential (TRP) ion channel, TRPV1, in 2013. This methodical breakthrough opened up a whole new world for structural biology and ion channel aficionados alike. TRP channels capture the imagination due to the sheer endless number of tasks they carry out in all aspects of animal physiology. To date, structures of at least one representative member of each of the six mammalian TRP channel subfamilies as well as of a few non-mammalian families have been determined. These structures were instrumental for a better understanding of TRP channel function and …
Marketing communication strategy of Finnish and Japanese mobile game developers and publishers
2017
Both the marketing communication strategy of mobile game industry and the industry itself have been drastically evolving in the past years since the development of computation, data transfer and communication technology on mobile devices. Marketing communication has been considered a significant part in marketing strategy, but the marketing communication strategy, activity and channels were not well investigated so far. In this study, 9 SMEs Finnish and Japanese mobile game developers and publishers provided their experience on how they built up marketing communication strategy for their targeting markets, which marketing communication channels they have used and how they chose the channels…
The effect of marketing communication on business relationship loyalty
2017
Purpose The purpose of this paper is to create a new understanding of industrial business-to-business (B2B) relationships by connecting the theoretical streams of marketing communications and relationship marketing. This study tests how various marketing communication channels and communication quality increase the transformation of customer-perceived value into customer loyalty. Design/methodology/approach The theoretical framework consists of links between customer-perceived value, marketing communication quality, channel effectiveness, and customer loyalty. The age of the business relationship is also taken into consideration. Empirical testing is based on global survey data (n=121) col…
An empirical analysis of online price dispersion in the Italian airline industry
2015
Firms operating in the electronic marketplace set and adjust prices to affect demand and profitability. In service markets, such as airline markets, different prices are commonly offered by diverse firms to accommodate to a variety of market segments having particular sets of consumer attitudes. This variation in prices is the price dispersion and is based on market distinctiveness deriving from customer heterogeneity as well as the peculiar competition in the specific market arena. In this paper we use a panel dataset from the Italian airline market to investigate the role of competition and different online channels in the emergence of price dispersion. Specifically, we examine the unclea…
Hydraulic jumps at drop and abrupt enlargement in rectangular channel
2002
The different types of hydraulic jumps that occur in a rectangular channel at an abrupt increase in section are experimentally studied. The abrupt section increase is due to both a drop and an increase in the channel width. Experiments were carried out with three different values of the ratio L/l between the channel widths respectively downstream and upstream of the abrupt section increase. For each L/l value five values of Froude number F1, of the supercritical flow upstream of the section increase were considered, and for each of them live values of the depth y1 of the same flow. The experiments showed that, as the depth y2 of the downstream subcritical flow increases, several types of hy…
Ion conduction in the KcsA potassium channel analyzed with a minimal kinetic model.
2004
We use a model by Nelson to study the current-voltage and conductance-concentration curves of bacterial potassium channel KcsA without assuming rapid ion translocation. Ion association to the channel filter is rate controlling at low concentrations, but dissociation and transport in the filter can limit conduction at high concentration for ions other than ${\mathrm{K}}^{+}$. The absolute values of the effective rate constants are tentative but the relative changes in these constants needed to qualitatively explain the experiments should be of significance.
On Equivalent Random Traffic method extension
2011
The key result of the paper is the Equivalent Random Traffic (ERT) method extension for estimation of the throughput for schemes with traffic splitting. The excellent accuracy (relative error is less than 1%) is shown in numerical example. A numerical algorithm is given — how to estimate the throughput for schemes at traffic splitting and merging. The paper also contains new Erlang-B formula algorithm for non-integer number of channels based on parabolic approximation.
TRPA1 channel is a cardiac target of mIGF-1/SIRT1 signaling.
2014
Cardiac overexpression of locally acting muscle-restricted (m)IGF-1 and the consequent downstream activation of NAD+-dependent protein deacetylase sirtuin 1 (SIRT1) trigger potent cardiac antioxidative and antihypertrophic effects. Transient receptor potential (TRP) cation channel A1 (TRPA1) belongs to the TRP ion channel family of molecular detectors of thermal and chemical stimuli that activate sensory neurons to produce pain. Recently, it has been shown that TRPA1 activity influences blood pressure, but the significance of TRPA1 in the cardiovascular system remains elusive. In the present work, using genomic screening in mouse hearts, we found that TRPA1 is a target of mIGF-1/SIRT1 sign…
Regulation of Calcium Channel Activity by Lipid Domain Formation in Planar Lipid Bilayers
2003
The sarcoplasmic reticulum channel (ryanodine receptor) from cardiac myocytes was reconstituted into planar lipid bilayers consisting of 1-palmitoyl-2-oleoyl-phosphatidylethanolamine (POPE) and 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) in varying ratios. The channel activity parameters, i.e., open probability and average open time and its resolved short and long components, were determined as a function of POPE mole fraction (X(PE)) at 22.4 degrees C. Interestingly, all of these parameters exhibited a narrow and pronounced peak at X(PE) approximately 0.80. Differential scanning calorimetric measurements on POPE/POPC liposomes with increasing X(PE) indicated that the lipid bilayer ente…
Cell Systems Bioelectricity: How Different Intercellular Gap Junctions Could Regionalize a Multicellular Aggregate
2021
Simple Summary Electric potential patterns across tissues are instructive for development, regeneration, and tumorigenesis because they can influence transcription, migration, and differentiation through biochemical and biomechanical downstream processes. Determining the origins of the spatial domains of distinct potential, which in turn decide anatomical features such as limbs, eyes, brain, and heart, is critical to a mature understanding of how bioelectric signaling drives morphogenesis. We studied theoretically how connexin proteins with different voltage-gated gap junction conductances can maintain multicellular regions at distinct membrane potentials. We analyzed a minimal model that i…