Mobile travel services: the effect of moderating context factors

This article has two objectives: (1) to draw an international comparison regarding the acceptance of mobile travel services in three countries with different profiles when it comes to travelling and mobile telecommunications, and (2) to extend relevant literature on mobile applications, more specifically travel services, by including context-related concepts, taking moderating factors like location, mobility of users, physical, and social context into account. Based on surveys that were carried out in 2009, structural equation modelling is used to identify differences in patterns in the use of mobile travel services and in the role of context-related variables. the conclusion of this article is that context-related factors, that is, mobility and (physical and social) context, have an impact on the relationship between the core concepts of technology Acceptance model (TAM) and Diffusion of Innovation (DoI) research. many studies on the acceptance and use of mobile services indicate that a deep understanding is needed of individual, context-related, and technological characteristics and the way they interact. this is also highly relevant to the travel industry, which wants to utilize the opportunities provided by mobile technology

Submerged freeze gripper to manipulate Micro-objects.

International audienceManipulating microscopic objects with the necessary dexterity still remains a very challenging task. In this paper, we propose a freeze gripper able to manipulate micro-objects in an innovative way, i.e. in submerged surroundings. We first review the influences of dry and liquid media on contact forces and non contact forces. This comparative analyse clearly shows the interest of the liquid medium. A survey of different microhandling systems based on the use of ice is also given. Then submerged microgripper with frozen water as an active end-effector is porposed as a promising new approach for manipulating low thermal conductive micro-objects. A prototype using the Peltier effect has been numerically modeled and developed. It is described in the paper. Experimental results validate the cooling and warming of the freeze gripper. A generic micromanipulation task is the purpose of further work

Mobile travel services: A three-country study into the impact of local circumstances

In this paper we explore the difference in acceptance patterns of mobile services that are related to travelling in three countries: Finland, The Netherlands and New Zealand. The objective of this paper is to understand differences in the use of Mobile Travel Services in three countries that differ with regard to national travel patterns. This paper also contributes to the discussion of the relevance of the Technology Acceptance Model for mobile applications by focusing on the importance of context characteristics, such as the degree of mobility of the user, the social situation people are in, and their need for social interaction. Based on surveys in the three countries as executed in 2009, we use structural equation modelling to find differences in patterns. The paper concludes that context factors have an impact on the relation between the core concepts as used in TAM and DOI approach, and that t here is a clear need for closer research in the moderating effect of physical (e.g. mobile and fixed context) and social context, as well as the need for social interaction. Moreover it is clear that country specific characteristics play a role in the acceptance of mobile travel services. As we pointed out in many of our research projects before the acceptance and use of mobile services requires deep understanding from individual, context and technology related characteristics and their mutual interactions

On the Incidence of C IV Absorbers Along the Sightlines to Gamma-Ray Bursts

We report on the statistics of strong (W_r > 0.15 A) C IV absorbers at z=1.5-3.5 toward high-redshift gamma-ray bursts (GRBs). In contrast with a recent survey for strong Mg II absorption systems at z < 2, we find that the number of C IV absorbers per unit redshift dN/dz does not show a significant deviation from previous surveys using quasi-stellar objects (QSOs) as background sources. We find that the number density of C IV toward GRBs is dN/dz(z~1.5)= 2.2 +2.8/-1.4, dN/dz(z~2.5)= 2.3 +1.8/-1.1 and dN/dz(z~3.5)= 1.1 +2.6/-0.9. These numbers are consistent with previous C IV surveys using QSO spectra. Binning the entire dataset, we set a 95% c.l. upper limit to the excess of C IV absorbers along GRB sightlines at twice the incidence observed along QSO sightlines. Furthermore, the distribution of equivalent widths of the GRB and QSO samples are consistent with being drawn from the same parent population. Although the results for Mg II and C IV absorbers along GRB sightlines appear to contradict one another, we note that the surveys are nearly disjoint: the C IV survey corresponds to higher redshift and more highly ionized gas than the Mg II survey. Nevertheless, analysis on larger statistical samples may constrain properties of the galaxies hosting these metals (e.g. mass, dust content) and/or the coherence-length of the gas giving rise to the metal-line absorption.Comment: Accepted version (for publication in ApJ), results unchanged, 18 pages, 3 tables, 5 figure

Principo de micromanipulacion inmersa por hielo.

International audienceUno de los mayores problemas en la manipulación y ensamble de micro-objetos cuyo tamaño está comprendido entre un micrómetro y un milímetro es el desarrollo de estrategias de prensión altamente fiables y precisas, particularmente durante la fase de liberación del micro-objeto [1], [2]. Además, cuando las dimensiones del objeto son inferiores a 100 µm, la fase de liberación está fuertemente perturbada por el ambiente [3], [4]. Un análisis comparativo en [5] muestra que la manipulación inmersa reduce considerablemente las perturbaciones: (i) las fuerza de pull-off y las fuerzas de van der Waals y electrostática disminuyen; (ii) la fuerza de capilaridad se cancela; (iii) la fuerza hidrodinámica se incrementa. Estos fenómenos tienen dos consecuencias: por un lado, las perturbaciones electrostáticas y de adhesión se reducen drásticamente; y por el otro, la velocidad máxima del micro-objeto es limitada, reduciendo su pérdida. Los prensores por hielo ya han sido utilizados en el aire para la manipulación de objetos según se describe en [6]-[9]. Sin embargo su miniaturización está limitada principalmente por los problemas causados por la fuerza de capilaridad. Este tipo de manipuladores proveen altas fuerzas de prensión y son capaces de manipular objetos de casi cualquier tipo de material y forma, aunque los objetos de baja conductividad térmica son recomendados. Actualmente, el tamaño de los objetos manipulados es superior a los 200 µm. El micromanipulador inmerso por hielo propuesto saca ventaja de la anulación de la fuerza de capilaridad permitiendo la manipulación de objetos inferiores a 100 µm. Su principal aplicación se encuentra en la micromecánica y el ensamble de microcomponentes ópticos, mecánicos o eléctricos. Este trabajo está estructurado como sigue: la sección II presenta el dispositivo experimental del micromanipulador inmerso por hielo; la sección III describe los circuitos térmicos (circuito RC equivalentes) de dos de sus subsistemas; finalmente, la sección IV muestra la validación experimental del circuito térmico dinámico analizado, así como las primeras manipulaciones

Gauge-independent MS‾\overline{MS} renormalization in the 2HDM

We present a consistent renormalization scheme for the CP-conserving Two-Higgs-Doublet Model based on $\overline{MS}$ renormalization of the mixing angles and the soft-$Z_2$-symmetry-breaking scale $M_{sb}$ in the Higgs sector. This scheme requires to treat tadpoles fully consistently in all steps of the calculation in order to provide gauge-independent $S$-matrix elements. We show how bare physical parameters have to be defined and verify the gauge independence of physical quantities by explicit calculations in a general $R_{\xi}$-gauge. The procedure is straightforward and applicable to other models with extended Higgs sectors. In contrast to the proposed scheme, the $\overline{MS}$ renormalization of the mixing angles combined with popular on-shell renormalization schemes gives rise to gauge-dependent results already at the one-loop level. We present explicit results for electroweak NLO corrections to selected processes in the appropriately renormalized Two-Higgs-Doublet Model and in particular discuss their scale dependence.Comment: 52 pages, PDFLaTeX, PDF figures, JHEP version with Eq. (5.23) correcte

Transgenic expression of the dicotyledonous pattern recognition receptor EFR in rice leads to ligand-dependent activation of defense responses

Plant plasma membrane localized pattern recognition receptors (PRRs) detect extracellular pathogen-associated molecules. PRRs such as Arabidopsis EFR and rice XA21 are taxonomically restricted and are absent from most plant genomes. Here we show that rice plants expressing EFR or the chimeric receptor EFR::XA21, containing the EFR ectodomain and the XA21 intracellular domain, sense both Escherichia coli- and Xanthomonas oryzae pv. oryzae (Xoo)-derived elf18 peptides at sub-nanomolar concentrations. Treatment of EFR and EFR::XA21 rice leaf tissue with elf18 leads to MAP kinase activation, reactive oxygen production and defense gene expression. Although expression of EFR does not lead to robust enhanced resistance to fully virulent Xoo isolates, it does lead to quantitatively enhanced resistance to weakly virulent Xoo isolates. EFR interacts with OsSERK2 and the XA21 binding protein 24 (XB24), two key components of the rice XA21-mediated immune response. Rice-EFR plants silenced for OsSERK2, or overexpressing rice XB24 are compromised in elf18-induced reactive oxygen production and defense gene expression indicating that these proteins are also important for EFR-mediated signaling in transgenic rice. Taken together, our results demonstrate the potential feasibility of enhancing disease resistance in rice and possibly other monocotyledonous crop species by expression of dicotyledonous PRRs. Our results also suggest that Arabidopsis EFR utilizes at least a subset of the known endogenous rice XA21 signaling components

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE