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

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

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

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

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

Multiwavelength study of the G345.5+1.5 region

Context. The star formation process requires the dust and gas present in the Milky Way to self-assemble into dense reservoirs ofneutral material where the new generation of stars will emerge. Star-forming regions are usually studied in the context of Galacticsurveys, but dedicated observations are sometimes needed when the study reaches beyond the survey area.Aims. A better understanding of the star formation process in the Galaxy can be obtained by studying several regions. This allowsincreasing the sample of objects (clumps, cores, and stars) for further statistical works and deeper follow-up studies. Here, we studiedthe G345.5+1.5 region, which is located slightly above the Galactic plane, to understand its star formation properties.Methods. We combined the Large Apex BOlometer CAmera (LABOCA) and 12 CO(4−3) transition line (NANTEN2) observationscomplemented with the Hi-GAL and Spitzer-GLIMPSE surveys to study the star formation toward this region. We used the Clumpfindalgorithm to extract the clumps from the 870 μm and 12 CO(4−3) data. Radio emission at 36 cm was used to estimate the number ofH ii regions and to remove the contamination from the free-free emission at 870 μm. We employed color-color diagrams and spectralenergy distribution (SED) slopes to distinguish between prestellar and protostellar clumps. We studied the boundedness of the clumpsthrough the virial parameter. Finally, we estimated the star formation efficiency (SFE) and star formation rate (SFR) of the region andused the Schmidt-Kennicutt diagram to compare its ability to form stars with other regions of the Galactic plane.Results. Of the 13 radio sources that we found using the MGPS-2 catalog, 7 are found to be associated with H ii regions correspondingto late-B or early-O stars. We found 45 870 μm clumps with diameters between 0.4 and 1.2 pc and masses between 43 M and3923 M , and 107 12 CO clumps with diameters between 0.4 pc and 1.3 pc and masses between 28 M and 9433 M . More than 50%of the clumps are protostellar and bounded and are able to host (massive) star formation. High SFR and SFR density (ΣS FR ) valuesare associated with the region, with an SFE of a few percent.Conclusions. With submillimeter, CO transition, and short-wavelength infrared observations, our study reveals a population of mas-sive stars, protostellar and bound starless clumps, toward G345.5+1.5. This region is therefore actively forming stars, and its locationin the starburst quadrant of the Schmidt-Kennicutt diagram is comparable to other star-forming regions found within the Galacticplane.Fil: Figueira, M.. Aix Marseille Universite; FranciaFil: Lopez Calderon, C.. Joint Alma Observatory; ChileFil: Bronfman, L.. Universidad de Chile. Facultad de Ciencias Físicas y Matemáticas; ChileFil: Zavagno, A.. Aix Marseille Universite; FranciaFil: Hervias Caimapo C.. University of Manchester; Reino UnidoFil: Duronea, Nicolas Urbano. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Åke Nyman, Lars. Joint Alma Observatory; Chil

Millimeter and far-IR study of the IRDC SDC 341.232-0.268

We analyze the molecular gas and dust associated with the infrared dark cloud SDC 341.232-0.268 in order to investigate the characteristics and parameters of the gas, determine the evolutionary status of four embedded EGO candidates and establish possible infall or outflow gas motions. We based our study on 12CO(2-1), 13 CO(2-1), and C18O(2-1) data obtained with the APEX telescope, molecular data of high density tracers from the MALT90 survey and IR images from Spitzer, Herschel and ATLASGAL. The study reveals two clumps at -44 km/s towards the IRDC, with  densities of > 10^4 cm-3 , typical of IRDCs, while high density tracers show H2 densities > 10^5 . FIR images reveals the presence of cold dust linked to the molecular clumps and EGOs. A comparison of spectra of the optically thin and optically thick molecular lines towards the EGOs suggests the existence of infall and outflow motions.Fil: Vazzano, María Mercedes. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Cappa, Cristina Elisabeth. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Firpo, Verónica. Universidad de La Serena; ChileFil: Lopez Carballo, C. H.. Universidad de La Serena; ChileFil: Rubio, Mónica. Universidad de Chile; ChileFil: Duronea, Nicolas Urbano. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentin

Comparative evaluation of solubility, cytotoxicity and photostability studies of resveratrol and oxyresveratrol loaded nanosponges

Resveratrol and oxyresveratrol are natural polyphenolic stilbenes with several important pharmacological activities. However, low solubility and aqueous instability are the major limitations in their drug delivery applications. In the present work, we demonstrated the encapsulation of resveratrol and oxyresveratrol with nanosponge to improve solubility and stability. Several characterization techniques were used to confirm the encapsulation of both drug molecules within the nanosponges. The high encapsulation efficiency of resveratrol (77.73%) and oxyresveratrol (80.33%) was achieved within the nanosponges. Transmission electron microscopy suggested uniform spherical size particles of resveratrol and oxyresveratrol loaded nanosponges. Compared to free drugs, better protection against UV degradation was observed for resveratrol-loaded nanosponge (2-fold) and oxyresveratrol-loaded nanosponge (3-fold). Moreover, a higher solubilization of resveratrol- and oxyresveratrol-loaded nanosponges lead to a better antioxidant activity compared to drug molecules alone. Cytotoxicity studies against DU-145 prostate cancer cell lines further suggested improved activity of both resveratrol and oxyresveratrol-loaded nanosponges without any significant toxicity of blank nanosponges