643 research outputs found
The brand likeability scale: an exploratory study of likeability in firm-level brands
We develop a new measurement scale to assess consumers’ brand likeability in firm-level brands. We present brand likeability as a multi-dimensional construct. In the context of service experience purchases, we find that increased likeability in brands results in (1) greater amount of positive association, (2) increased interaction interest, (3) more personified quality, and (4) increased brand contentment. The four-dimensional multiple-item scale demonstrates good psychometric properties, showing strong evidence of reliability as well as convergent, discriminant, and nomological validity. Our findings reveal that brand likeability is positively associated with satisfaction and positive word-of-mouth. The scale extends existing branding research, providing brand managers with a metric so that likeability can be managed strategically. It addresses the need for firms to act more likeable in an interaction-dominated economy. Focusing on likeability acts as a differentiator and encourages likeable brand personality traits. We present theoretical implications and future research directions on the holistic brand likeability concept
Infrared Studies of the Onset of Conductivity in Ultra-Thin Pb Films
In this paper we report the first experimental measurement of the infrared
conductivity of ultra-thin quenched-condensed Pb films. For dc sheet
resistances such that the ac conductance increases with
frequency but is in disagreement with the predictions of weak localization. We
attribute this behavior to the effects of an inhomogeneous granular structure
of these films, which is manifested at the very small probing scale of infrared
measurements. Our data are consistent with predictions of two-dimensional
percolation theory.Comment: Submitted to Physical Review Letter
A Mechanical Mass Sensor with Yoctogram Resolution
Nanoelectromechanical systems (NEMS) have generated considerable interest as
inertial mass sensors. NEMS resonators have been used to weigh cells,
biomolecules, and gas molecules, creating many new possibilities for biological
and chemical analysis [1-4]. Recently, NEMS-based mass sensors have been
employed as a new tool in surface science in order to study e.g. the phase
transitions or the diffusion of adsorbed atoms on nanoscale objects [5-7]. A
key point in all these experiments is the ability to resolve small masses. Here
we report on mass sensing experiments with a resolution of 1.7 yg (1 yg =
10^-24 g), which corresponds to the mass of one proton, or one hydrogen atom.
The resonator is made of a ~150 nm long carbon nanotube resonator vibrating at
nearly 2 GHz. The unprecedented level of sensitivity allows us to detect
adsorption events of naphthalene molecules (C10H8) and to measure the binding
energy of a Xe atom on the nanotube surface (131 meV). These ultrasensitive
nanotube resonators offer new opportunities for mass spectrometry,
magnetometry, and adsorption experiments.Comment: submitted version of the manuscrip
Investigation of antioxidant effects of rosmarinic acid on liver, lung and kidney in rats: a biochemical and histopathological study
Background: The aim of the study was to investigate the protective effects of rosmarinic acid in rats exposed to hepatic ischaemia/reperfusion (I/R) injury.
Materials and methods: Thirty-two rats were randomly classified into four groups of 8 rats each: laparotomy without medication, rosmarinic acid (dose of 50 mg/kg via oral gavage) followed by laparotomy, laparotomy followed by hepatic I/R, and hepatic I/R with rosmarinic acid. Serum aspartate aminotransferase, alaninÄ™ aminotransferase, and malondialdehyde levels and total oxidant activity and total antioxidant capacity levels of the liver, lung, and kidney were assessed. The histopathologic assessment was also performed.
Results: Rosmarinic acid significantly reduced liver function test parameters and decreased oxidative stress and abnormal histopathologic findings in the liver. The oxidative stress in the lung significantly increased in the I/R group but significantly decreased in the I/R + rosmarinic acid group due to the addition of rosmarinic acid. Rosmarinic acid led to no reduction in oxidative stress in kidney following hepatic I/R injury. There were no statistically significant differences among the groups regarding histopathologic changes in kidney and lung sections.
Conclusions: Rosmarinic acid has antioxidant properties and is an effective hepatoprotective agent. However, although rosmarinic acid provides useful effects in the lung by increasing antioxidant capacity and reducing oxidative stress after I/R injury, it does not ameliorate histopathologic changes. These findings suggest that rosmarinic acid is likely to provide favourable outcomes in the treatment of hepatic I/R injury
Anisotropic Magnetoconductance in Quench-Condensed Ultrathin Beryllium Films
Near the superconductor-insulator (S-I) transition, quench-condensed
ultrathin Be films show a large magnetoconductance which is highly anisotropic
in the direction of the applied field. Film conductance can drop as much as
seven orders of magnitude in a weak perpendicular field (< 1 T), but is
insensitive to a parallel field in the same field range. We believe that this
negative magnetoconductance is due to the field de-phasing of the
superconducting pair wavefunction. This idea enables us to extract the finite
superconducting phase coherence length in nearly superconducting films. Our
data indicate that this local phase coherence persists even in highly
insulating films in the vicinity of the S-I transition.Comment: 4 pages, 4 figure RevTex, Typos Correcte
Electrical transport studies of quench condensed Bi films at the initial stage of film growth: Structural transition and the possible formation of electron droplets
The electrical transport properties of amorphous Bi films prepared by
sequential quench deposition have been studied in situ. A
superconductor-insulator (S-I) transition was observed as the film was made
increasingly thicker, consistent with previous studies. Unexpected behavior was
found at the initial stage of film growth, a regime not explored in detail
prior to the present work. As the temperature was lowered, a positive
temperature coefficient of resistance (dR/dT > 0) emerged, with the resistance
reaching a minimum before the dR/dT became negative again. This behavior was
accompanied by a non-linear and asymmetric I-V characteristic. As the film
became thicker, conventional variable-range hopping (VRH) was recovered. We
attribute the observed crossover in the electrical transport properties to an
amorphous to granular structural transition. The positive dR/dT found in the
amorphous phase of Bi formed at the initial stage of film growth was
qualitatively explained by the formation of metallic droplets within the
electron glass.Comment: 7 pages, 6 figure
A Universality in Oscillating Flows
We show that oscillating flow of a simple fluid in both the Newtonian and the
non-Newtonian regime can be described by a universal function of a single
dimensionless scaling parameter , where is the oscillation
(angular) frequency and is the fluid relaxation-time; geometry and
linear dimension bear no effect on the flow. Experimental energy dissipation
data of mechanical resonators in a rarefied gas follow this universality
closely in a broad linear dimension ( m m) and
frequency ( Hz Hz) range. Our results suggest a
deep connection between flows of simple and complex fluids.Comment: To be published in Physical Review Letter
Nonlinear damping in mechanical resonators based on graphene and carbon nanotubes
Carbon nanotubes and graphene allow fabricating outstanding nanomechanical
resonators. They hold promise for various scientific and technological
applications, including sensing of mass, force, and charge, as well as the
study of quantum phenomena at the mesoscopic scale. Here, we have discovered
that the dynamics of nanotube and graphene resonators is in fact highly exotic.
We propose an unprecedented scenario where mechanical dissipation is entirely
determined by nonlinear damping. As a striking consequence, the quality factor
Q strongly depends on the amplitude of the motion. This scenario is radically
different from that of other resonators, whose dissipation is dominated by a
linear damping term. We believe that the difference stems from the reduced
dimensionality of carbon nanotubes and graphene. Besides, we exploit the
nonlinear nature of the damping to improve the figure of merit of
nanotube/graphene resonators.Comment: main text with 4 figures, supplementary informatio
The characteristics of smoking habit among patients evaluated at our outpatient clinic
To determine the prevalence of cigarette smoking, to examine the risk factors affecting smoking amongst adults and to assess the opinion of patients about quitting smoking who were evaluated at our outpatient clinic. Six hundred fifty-nine patients who were evaluated at our outpatient clinic between June 2005 and June 2006 were included in the study. This is a cross-sectional study that evaluates prevalence of smoking. Data gathered by applying face to face questionnaires. The mean age of 659 participants [417 (63.3%) males and 242 (36.7%) females] was 53.1 ± 16.2 years. The prevalences were; 33% (n= 218) smokers, 39% (n= 258) ex-smokers and 28% (n= 183) non-smokers. Smoking prevalence under age of 50 was significantly higher (p= 0.0001). There was a positive significant relation between education and smoking amongst women, but this relationship was not significant amongst men. The most common reason for beginning smoking was because of friends (72%). 86% wanted to quit smoking. 48.9% tried to quit smoking but couln't be successful. The prevalence of active smoking and quit smoking among patients who applied to pulmonary medicine outpatient clinic were 33% and 28%, respectively. The ratio of smoking and smoking pack-years was higher among men. Eighty-six percent of patients wanted to quit, 25% tried to quit but could not be successful, and 49% quit smoking but began smoking again. According to these findings, patients who were smoking wanted to quit but couln't be successful without a professional help. We planned to found a smoking cessation outpatient clinic at our department
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