2,786 research outputs found
Measurement of an integral of a classical field with a single quantum particle
A method for measuring an integral of a classical field via local interaction
of a single quantum particle in a superposition of 2^N states is presented. The
method is as efficient as a quantum method with N qubits passing through the
field one at a time and it is exponentially better than any known classical
method that uses N bits passing through the field one at a time. A related
method for searching a string with a quantum particle is proposed.Comment: 3 page
Sensing the light environment in plants: photoreceptors and early signaling steps.
Plants must constantly adapt to a changing light environment in order to optimize energy conversion through the process of photosynthesis and to limit photodamage. In addition, plants use light cues for timing of key developmental transitions such as initiation of reproduction (transition to flowering). Plants are equipped with a battery of photoreceptors enabling them to sense a very broad light spectrum spanning from UV-B to far-red wavelength (280-750nm). In this review we briefly describe the different families of plant photosensory receptors and the mechanisms by which they transduce environmental information to influence numerous aspects of plant growth and development throughout their life cycle
Curved Graphene Nanoribbons: Structure and Dynamics of Carbon Nanobelts
Carbon nanoribbons (CNRs) are graphene (planar) structures with large aspect
ratio. Carbon nanobelts (CNBs) are small graphene nanoribbons rolled up into
spiral-like structures, i. e., carbon nanoscrolls (CNSs) with large aspect
ratio. In this work we investigated the energetics and dynamical aspects of
CNBs formed from rolling up CNRs. We have carried out molecular dynamics
simulations using reactive empirical bond-order potentials. Our results show
that similarly to CNSs, CNBs formation is dominated by two major energy
contribution, the increase in the elastic energy due to the bending of the
initial planar configuration (decreasing structural stability) and the
energetic gain due to van der Waals interactions of the overlapping surface of
the rolled layers (increasing structural stability). Beyond a critical diameter
value these scrolled structures can be even more stable (in terms of energy)
than their equivalent planar configurations. In contrast to CNSs that require
energy assisted processes (sonication, chemical reactions, etc.) to be formed,
CNBs can be spontaneously formed from low temperature driven processes. Long
CNBs (length of 30.0 nm) tend to exhibit self-folded racket-like
conformations with formation dynamics very similar to the one observed for long
carbon nanotubes. Shorter CNBs will be more likely to form perfect scrolled
structures. Possible synthetic routes to fabricate CNBs from graphene membranes
are also addressed
Sinais climáticos em anéis de crescimento de Cedrela fissilis em diferentes tipologias de florestas ombrófilas do Sul do Brasil.
Os anéis de crescimento de Cedrela fissilis foram analisados em duas unidades fitogeográficas do estado do Paraná, em áreas de Florestas Ombrófilas Densa e Mista, litoral e planalto, no domínio da Floresta Atlântica, buscando encontrar sinais climáticos nas séries radiais temporais de anéis de crescimento. As áreas não apresentam estação seca bem definida, com precipitações bem distribuídas ao longo do ano. Na área do litoral, as temperaturas são altas e constantes durante todo o ano, enquanto que na área do planalto as temperaturas são mais amenas, ocorrendo considerável variação durante o ano. Nas duas áreas foram coletadas 3-4 amostras radiais dos indivíduos selecionados, sendo 15 no litoral e 21 no planalto. Os anéis de crescimento foram marcados, mensurados, submetidos ao controle de qualidade por meio do programa COFECHA® e as cronologias foram geradas utilizando o programa ARSTAN®. Sinais climáticos nas séries foram identificados utilizando-se Correlações de Pearson. As séries analisadas provenientes da área de planalto apresentaram melhores correlações com as variáveis temperatura e precipitação, sendo identificados sinais climáticos, enquanto que as séries do litoral não puderam ser datadas com total acurácia. É atribuída a hipótese da competição, principalmente por luz, para explicar a dificuldade na datação dos indivíduos do litoral
Spin-orbit mode transfer via a classical analog of quantum teleportation
We translate the quantum teleportation protocol into a sequence of coherent
operations involving three degrees of freedom of a classical laser beam. The
protocol, which we demonstrate experimentally, transfers the polarisation state
of the input beam to the transverse mode of the output beam. The role of
quantum entanglement is played by a non-separable mode describing the path and
transverse degrees of freedom. Our protocol illustrates the possibility of new
optical applications based on this intriguing classical analogue of quantum
entanglement.Comment: 5 pages, 7 figure
Dendroecology of Gymnanthes klotzschiana Müll. Arg. trees, naturally growing in Northern Uruguay.
Ameridendro
Impact of non-commercial recommendations on store attributes salience: an empirical study
The present study aims to investigate the impact of non-commercial recommendation sources on retail
store-attributes perceived salience. The study was directed to electronics bricks-and-mortar retail stores.
For that purpose, an empirical quantitative study was conducted with face-to-face interviews, using a
sample of 555 store customers. In the quantitative hypothesis testing, we correlated the store-attributes
perceived salience with the possible non-commercial recommendation sources. The results revealed several
positive correlations. Every recommendation source analyzed had between five to thirteen positive
significant correlations, out of fifteen possible. The most expressive correlations found were between the
variables: the store attribute "cozy/elegant" and the recommendation sources "other customers", "third
parties" and "friends or family"; the store attribute "possibility to choose between different models of one
product" with the recommendation sources "friends or family", "third parties" and "other customers"; the
store attribute "the store carries the latest products" with the recommendation sources "other customers",
"friends or family" and "third parties”.info:eu-repo/semantics/publishedVersio
Do Brands "JUST DO IT"? Studying the Effectiveness of B2C Slogans
This study aims to contribute to a more effective creation and management of slogans in the context of branding and advertising, testing which factors might influence the brand slogan recall and recognition.
An empirical study was conducted, via a self-administrated original questionnaire, applied to a sample of 156 elements, analyzing the recall and recognition rates for twenty-nine slogans, from nine different product categories: retailing, cokes, juices, water, sports, telecoms (mobiles), beer, personal care and ice-cream. The independent variables used to analyze each slogan recall and recognition were: slogan length, slogan antiqueness, brand industry, slogan language, brand consuming frequency and sympathy towards the brand.
A positive relation was found between the antiqueness of slogans and their spontaneous recall. It was also found that the spontaneous recall of slogans has high variation among brands and shorter slogans have higher recall rates. Other variables (slogan language, brand consuming frequency and sympathy towards the brand) did not showed a significant impact on the recall/recognition of slogans
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