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141.
David Manneck Gisela Manz Hannah-Sophie Braun Julia Rosendahl Friederike Stumpff 《International journal of molecular sciences》2021,22(10)
A therapeutic potential of the TRPA1 channel agonist cinnamaldehyde for use in inflammatory bowel disease is emerging, but the mechanisms are unclear. Semi-quantitative qPCR of various parts of the porcine gastrointestinal tract showed that mRNA for TRPA1 was highest in the colonic mucosa. In Ussing chambers, 1 mmol·L−1 cinnamaldehyde induced increases in short circuit current (ΔIsc) and conductance (ΔGt) across the colon that were higher than those across the jejunum or after 1 mmol·L−1 thymol. Lidocaine, amiloride or bumetanide did not change the response. The application of 1 mmol·L−1 quinidine or the bilateral replacement of 120 Na+, 120 Cl− or 25 HCO3− reduced ΔGt, while the removal of Ca2+ enhanced ΔGt with ΔIsc numerically higher. ΔIsc decreased after 0.5 NPPB, 0.01 indometacin and the bilateral replacement of 120 Na+ or 25 HCO3−. The removal of 120 Cl− had no effect. Cinnamaldehyde also activates TRPV3, but comparative measurements involving patch clamp experiments on overexpressing cells demonstrated that much higher concentrations are required. We suggest that cinnamaldehyde stimulates the secretion of HCO3− via apical CFTR and basolateral Na+-HCO3− cotransport, preventing acidosis and damage to the epithelium and the colonic microbiome. Signaling may involve the opening of TRPA1, depolarization of the epithelium and a rise in PGE2 following a lower uptake of prostaglandins via OATP2A1. 相似文献
142.
Prediction of overall visual quality based on instrumental measurements is a challenging task. Despite the several proposed models and methods, there exists a gap between the instrumental measurements of print and human visual assessment of natural images. In this work, a computational model for representing and quantifying the overall visual quality of prints is proposed. The computed overall quality should correspond to the human visual quality perception when viewing the printed images. The proposed model is a Bayesian network which connects the objective instrumental measurements to the subjective opinion distribution of human observers. This relationship can be used to score printed images, and additionally, to computationally study the connections of the attributes. A novel graphical learning approach using an iterative evolve-estimate-simulate loop learning the quality model based on psychometric data and instrumental measurements is suggested. The network structure is optimised by applying evolutionary computation (evolve). The estimation of the Bayesian network parameters is within the evolutionary loop. In this loop, the maximum likelihood approach is used (estimate). The stochastic learning process is guided by priors devised from the psychometric subjective experiments (performance through simulation). The model reveals and represents the explanatory factors between its elements providing insight to the psychophysical phenomenon of how observers perceive visual quality and which measurable entities affect the quality perception. By using true data, the design choices are demonstrated. It is also shown that the best-performing network establishes a clear and intuitively correct structure between the objective measurements and psychometric data. 相似文献
143.
Goetz Botterweck J. Felix Hampe Stefan Stein Andreas Rosendahl 《Information Systems and E-Business Management》2009,7(3):275-299
In this paper we study mobile home automation, a field that emerges from an integration of mobile application platforms and
home automation technologies. We motivate our research and provide a conceptual introduction, which illustrates the need for
such applications by a two-dimensional conceptual model of mobility. As a first steps towards a solution we take the user’s
perspective and discuss different options of how he might access a mobile home automation service and the controlled devices.
Subsequently, we suggest a general system architecture for mobile home automation services and discuss related design decision.
This design has been implemented in a research prototype, which we named Remotile. This helps us to discuss typical components,
such as modules that integrate various home automation devices.
A previous version of this paper was presented at the Sixth International Conference on Mobile Business, 2007. “Andreas Rosendahl,
J. Felix Hampe, and Goetz Botterweck, Mobile Home Automation, Merging Mobile Value Added Services and Home Automation Technologies,
Proceedings, Sixth International Conference on Mobile Business, 8–11 July 2007, IEEE Computer Society, ISBN 0-7695-2803-1”. 相似文献
144.
A continuous-time accelerometer interface is feasible when a high dynamic range together with a wide signal band is required. In this paper the implementation of a continuous-time force-feedback loop for a capacitive sensor element with a full-scale signal of ±1.5 g is presented. The interface is measured to attain a noise equivalent acceleration (NEA) density of 500 at 30 Hz for the on-chip digitized output and 300 at 30 Hz for the analog output using a capacitive half-bridge sensor element with a single pair of electrodes. The essential circuit structures of the closed-loop sensor will be presented and analyzed in detail. 相似文献
145.
An interface and control electronics have been designed and implemented for a bulk micromachined capacitive gyroscope. The system is composed of an application-specific integrated circuit (ASIC) that implements the analog parts of the system and a field-programmable gate array (FPGA) chip that implements the digital signal processing part. Both the system architecture and details of the different circuit blocks will be discussed. The system utilizes phase coherent demodulation to resolve the final output signal. In a typical implementation, phase delay and phase noise in the clock generation cause the signal quality to degrade. A method for correcting these errors will be introduced. A prototype of a microelectromechanical gyroscope has been realized and characterized. The measurement results show that the gyroscope achieves 0.042°/s/ spot noise and 51.6-dB signal-to-noise ratio (SNR) over the 40-Hz bandwidth with a 100°/s input signal. 相似文献
146.
The distribution of ptaquiloside (PTA) was studied in four Danish bracken populations in order to evaluate the transfer of PTA from ferns to soil. Populations showed statistically significant differences in PTA contents of fronds and rhizomes despite large in-site variations. The highest concentrations were encountered in fronds with concentrations ranging between 213 and 2145 g/g, while rhizomes had concentrations between 11 and 902 g/g. PTA was present in soil materials in amounts of 0.22–8.49 g/g but apparently with no correlation with PTA contents of fronds or rhizomes. Laboratory tests showed that water could leach PTA from bracken fronds, which is in support of the high soil contents observed at sites exposed to heavy showers just before sampling. The observed soil contents correspond to estimated soil solution concentrations of 200–8500 g/liter, demonstrating a substantial risk of PTA contamination of surface water and groundwater. 相似文献
147.
Jonas Fritsch Søren Bro Pold Lasse Steenbock Vestergaard Melissa Lucas 《Personal and Ubiquitous Computing》2014,18(7):1551-1565
In this article, we present the interactive literary installation Ink, an experimental installation displayed at the Roskilde library, and the Roskilde Festival, which is designed to prompt public reflection on the nature and role of digital literature. By manipulating three books embedded with sensors, and watching text visualized on a 55” screen, members of the public select from a range of predefined sentences, previously created by a Danish author, and stored in a database. Squeezing the books alters each poetic line by degrees. The final poems print onto a library receipt for their producers and upload to a blog for public viewing. We present (1) design challenges to an installation meant to persuade people to engage affectively with the ergodic nature of digital literature and (2) an in-depth analysis of the empirical findings from the installation studies at the Roskilde Festival. In particular, we highlight the broad, rich range of performative interactions facilitated by the interactive setup. This analysis examines the performative writing and reading achieved by the public through interaction with Ink and also with the resultant poems. From this exploration, we discuss general tendencies when designing affectively engaging literary interactions at the edge of art and design. 相似文献
148.
While Moore’s law states that the number of transistors is approximately doubled every 2 years, powering these transistors simultaneously is only possible as long as Dennard scaling continues. Unfortunately, voltage scaling has slowed down in recent years, and microprocessor designers have hit what is known as the “utilization wall” or the “dark silicon” effect. Vectorization, parallelization, specialization and heterogeneity are the key approaches to deal with this utilization wall. However, how software developers can maximize energy efficiency of these architectures remains an open question. This paper presents an energy evaluation of parallelization using both physical and logical cores (i.e., SMT/Hyper-Threading), vectorization (SSE, Advanced Vector Extensions and NEON) and dynamic core reconfiguration [ \(\hbox {Intel}^{\circledR }\) ’s Turbo Boost Technology (TBT)]. The evaluation spans microprocessors for embedded, laptop, desktop and server markets, since there is a convergence among them towards energy efficiency. The analyzed processors include Intel’s Core \(^\mathrm{TM}\) i5 and i7 family and ARM \(^{\circledR }\) ’s Cortex \(^\mathrm{TM}\) A9 and A15. Results show that software developers should prioritize vectorization over thread parallelism when possible, as it yields better energy efficiency, especially on the Intel platforms. Application scalability can be reduced drastically when using vectorization and threading simultaneously since vectorization increases pressure on the memory subsystem. Intel’s TBT further improves energy efficiency by an additional 10–20 % depending on the number of active threads. 相似文献
149.
Oddershede N Løvstakken L Torp H Jensen JA 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2008,55(8):1744-1754
Wilson (1991) presented an ultrasonic wideband estimator for axial blood flow velocity estimation through the use of the 2-D Fourier transform. It was shown how a single velocity component was concentrated along a line in the 2-D Fourier space, where the slope was given by the axial velocity. Later, it was shown that this approach could also be used for finding the lateral velocity component by also including a lateral sampling. A single velocity component would then be concentrated along a plane in the 3-D Fourier space, tilted according to the 2 velocity components. This paper presents 2 new velocity estimators for finding both the axial and lateral velocity components. The estimators essentially search for the plane in the 3- D Fourier space, where the integrated power spectrum is largest. The first uses the 3-D Fourier transform to find the power spectrum, while the second uses a minimum variance approach. Based on this plane, the axial and lateral velocity components are estimated. Several phantom measurements, for flow-to-depth angles of 60, 75, and 90 degrees, were performed. Multiple parallel lines were beamformed simultaneously, and 2 different receive apodization schemes were tried. The 2 estimators were then applied to the data. The axial velocity component was estimated with an average standard deviation below 2.8% of the peak velocity, while the average standard deviation of the lateral velocity estimates was between 2.0% and 16.4%. The 2 estimators were also tested on in vivo data from a transverse scan of the common carotid artery, showing the potential of the vector velocity estimation method under in vivo conditions. 相似文献
150.
Amanda L. Snashall Lasse Norén Yun Liu Toru Yamashita Frank Brink Raymond L. Withers 《Ceramics International》2012
There are significant inconsistencies in published literature surrounding the phase analysis and physical properties of ceramics with the nominal composition BaO–Nd2O3–5TiO2 (BNT125). A careful phase analysis investigation of BNT125 ceramics using variable size TiO2 reagents was therefore undertaken using XRD, FESEM and EPMA with corresponding dielectric properties characterised over 2–3 GHz. Three distinct phases were consistently formed: Ba6?3xNd8+2xTi18O54 (x ~ 0.67), Ba2Ti9O20 and TiO2. The use of nano-scale TiO2 reagents significantly reduced porosity and improved the dielectric properties of the composite ceramics, while markedly reducing processing times. Structural and crystal chemical indications as to the origin of this system's physical properties are discussed, with these results providing new insights into optimisation paths for microwave dielectric materials of this type. 相似文献