1,721,044 research outputs found
A Systematic Review of Sustainable Supply Chain Management Practices in Food Industry
Full text linkThe food industry is central to human beings and heavily impacts the lives of the entire society. Nowadays, the sustainable development goal and the introduction of new information and communication technologies has led food companies to deal with this new paradigm. They require sustainable practices that have the dual objective of improving the overall performance of the company itself and fulfilling the sustainability requirement. Research works on sustainable supply chain management practices in the food industry is quite fragmented, as it often considers just a part of the chain. Therefore, through a systematic literature review, this paper aims to provide an up-to-date analysis of supply chain management practices within the scope of sustainability, studying the findings of 224 reviewed papers. The implications of this work are relevant for academic research as they enlarge the body of knowledge and highlight key points where there is the need to investigate further. From a practical point of view this study proposes an overview of the most common and adopted practices that can be implemented in order to achieve sustainable development in the food industry
Light-force-induced fluorescence line-center shifts in high-precision optical spectroscopy: simple model and experiment
No full textA simple model that enables to calculate the effects of dipole and radiation-pressure forces on the spectroscopic determination of energy separations was developed. The resulting model provides the means for recovering the redshift as well as for explaining a blueshift of the Lamb dipole line center for a closed transition in a beam of 4He atoms
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Precision measurement of the isotope shift of the 2 3S13 3P0 transition in helium
No full textA heterodyne spectroscopic scheme, using only one laser tuned to the atomic wavelength, is applied to the measurement of the He-3(F = 1/2-1/2 component)He-4 separation for the 2 S-3(1) - P-3(0) transition at 389 nm. The experimental result is 45 394 425(137) kHz and the isotope shift deduced in the absence of hyperfine structure is 42 184 180(139) kHz. A new value of the He-3 nuclear charge radius is obtained, [r2]1/2 = 1.923(36) fm, in a regime of low energy and momentum transfer
Spatial interference of coherent atomic waves by manipulation of the internal quantum state
No full textA trapped 87Rb Bose–Einstein condensate is initially put into a superposition of two internal states. Under the effect of gravity and by means of a second transition, we prepare two vertically displaced condensates in the same internal state. These constitute two coherent sources of matter waves with adjustable spatial separation. Fringe patterns, observed after free expansion, are associated with the interplay between internal and external degrees of freedom and substantially agree with those for a double-slit experiment
ISOTOPE EFFECT AND PRECISION-MEASUREMENT ON THE 2(3)S(1) - 3(3)P(0) TRANSITION OF HELIUM
No full textTime-domain atom interferometry across the threshold for Bose-Einstein condensation
No full textWe have performed time-domain interferometry experiments with matter waves trapped in a harmonic potential above and below the Bose-Einstein phase transition, by means of the method of separated oscillating fields, with a variable time delay T. We observe the oscillations of the population between two internal Zeeman states versus the delay T to be rapidly depleted both below and slightly above Bose-Einstein condensation. We give a quantitative explanation in terms of the phase evolution due to the entanglement between the internal and external degrees of freedom
Collision of impurities with Bose-Einstein condensates
No full textQuantum dynamics of impurities in a bath of bosons is a long-standing problem in solid-state, plasma, and atomic physics. Recent experimental and theoretical investigations with ultracold atoms have focused on this problem, studying atomic impurities immersed in an atomic Bose-Einstein condensate (BEC) and for various relative coupling strengths tuned by the Fano-Feshbach resonance technique. Here, we report extensive numerical simulations on a closely related problem: The collision between a bosonic impurity consisting of a few 41K atoms and a BEC of 87Rb atoms in a quasi one-dimensional configuration and under a weak harmonic axial confinement. For small values of the inter-species interaction strength (regardless of its sign), we find that the impurity, which starts from outside the BEC, simply causes the BEC cloud to oscillate back and forth, but the frequency of oscillation depends on the interaction strength. For intermediate couplings, after a few cycles of oscillation the impurity is captured by the BEC, and strongly changes its amplitude of oscillation. In the strong interaction regime, if the inter-species interaction is attractive, a local maximum (bright soliton) in the BEC density occurs where the impurity is trapped; if, instead, the inter-species interaction is repulsive, the impurity is not able to enter the BEC cloud and the reflection coefficient is close to one. However, if the initial displacement of the impurity is increased, the impurity is able to penetrate the cloud, leading to the appearance of a moving hole (dark soliton) in the BEC
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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