On the duality in four-dimensional Lorentz-breaking field theories

We consider new issues of duality in four-dimensional Lorentz-breaking field theories. In particular, we demonstrate that the arising of the aether-like Lorentz-breaking term is necessary in order for the 4D models to display the duality analog between the MCS and self-dual models in 3D. We further study the dispersion relations in both theories and discuss the physical contents of the models involved in this new dualilty.Comment: 16 page

Five-Dimensional QED, Muon Pair Production and Correction to the Coulomb Potential

We consider QED in five dimensions in a configuration where matter is localized on a 3-brane while foton propagates in the bulk. The idea is to investigate the effects of the Kaluza-Klein modes of the photon in the relativistic regime, but in low energy, and in the nonrelativistic regime. In the relativistic regime, we calculate the cross section for the reaction $e^+ + e^- \to \mu^+ + \mu^-$. We compare our theoretical result with a precise measurement of this cross section at $\sqrt{s}=57.77$ GeV. As result, we extract a lower bound on the size of the extra dimension. In the nonrelativistic regime, we derive the contribution for the Coulomb potential due to the whole tower of the Kaluza-Klein excited modes of the photon. We use the modified potential to calculate the Rutherford scattering differential cross section.Comment: minor changes, three new refs. added, to appear in IJMP

Green purchase behavior: A systematic review

Environmental sustainability is one of today’s most urgent concerns, on which human consumption is considered to have substantial impact. As a result of the ecosystems’ over-exploitation, the world faces unprecedented consequences such as greenhouse effects, climate change, wildlife extinction, air, soil and water pollution (Barbarossa and de Pelsmacker, 2016; Liobikienė et al., 2016; Rausch and Kopplin, 2021). The change into sustainable consumption constitutes a fundamental opportunity for reducing our impact and for economic growth, as the emerging consciousness increase the demand for green product innovations (Han et al., 2017; Olson, 2013). As a long trail of theories explores the motives behind this complex phenomenon, many of the evidence point towards a significant gap between consumer concerns and actual behavior, with many studies only able to predict purchase intention, as further confirmed in a set of eight systematic reviews and meta-analysis (Bamberg and Möser, 2007; Groening et al., 2018; Klöckner, 2013; Li et al., 2019; Loureiro et al., 2021; Rivis et al., 2009; Sheppard et al., 1988), which together encompass 292 different data tests, a combined sample of 59,550 observations and over 1,100 peer-reviewed documents. Aiming to tackle this well-documented gap, a systematic review was conducted using (Christofi et al., 2017; Tranfield et al., 2003). Our objective is to contribute towards a better understanding of what drives Actual Green Purchase Behavior (AGPB) by: (i) gathering a comprehensive collection of meaningful contributions; (ii) discussing emerging trends, dominant latent topics and constructs; (iii) synthesizing the main findings, gaps and contradictions. Database search for English peer-reviewed articles, was completed across all related business, social and environmental sciences on Scopus/Web of Science (WoS), not restricted to any specific publication period. In the initial set, 777 articles were extracted, after merging databases and removing duplicates. This number was reduced to 183 by the processes of title, abstract screening, and full-text reading. Final selection criteria were adapted from literature (Loureiro et al., 2021): (i) article fit with the research goals; (ii) robust use and development of theory within present literature; (iii) logical theory-methods-data flow; (iv) relevance of practical and theoretical contributions. The theories of Planned Behavior, Value-Belief-Norm and Norm Activation are the most influential, with their appropriateness verified across a widely diverse of PEB activities, mainly using quantitative methods. Despite the sizeable trail of research using these rational-based models, concerns are raised about their sufficiency (Liang et al., 2019; Perugini and Bagozzi, 2001; Sheppard et al., 1988) and thus additional influencers are suggested for further research, yet to be integrated and validated empirically into a single conceptual model. Three main types of concepts are identified as able to drive AGPB: cognitive, normative and emotional factors. Possessing a high level of knowledge has been found to exert influence on green behavioral processes (Rausch and Kopplin, 2021), which seems to be interconnected with the notion of environmental care (Policarpo and Aguiar, 2020) and with evaluating the perceived sum of benefits (Hamzah and Tanwir, 2021; Rezvani et al., 2018). On the other hand, the debate between altruistic norms and complying with socially appropriate forms of conduct, is one the main topics of discussion, with both personal and social norms described as strong motivational basis for behavior context (de Leeuw et al., 2015; Stern, 2000). Moreover, addressing the lower predictive value of cognitive and normative constructs, when attempting to explain actual behavior instead of intention, recent evidence suggests that the influence of emotions can outweigh cognitions (Liang et al., 2019) – or better yet, complement them - and ignite consumer decision making (Bagozzi et al., 1999; Han et al., 2018). Affective beliefs provide the required motivational content (Bechara et al., 2000; Perugini and Bagozzi, 2001) to trigger individual’s action, as also supported by neuroscience. Based on the present discussion, we propose the following propositions: P1: Cognitive factors are positively associated with AGPB; P2: Normative factors are positively associated with AGPB; P3: Emotional factors are positively associated with AGPB. Additional factors were found to influence AGPB, such as the coolness of brands, the role of category and cultural values. Regarding brand coolness, its role in activating passionate desire is demonstrated in the context of luxury fashion brands (Loureiro et al., 2020) and stablished as a positive quality, related to how brand personality resonates to consumers. Its specific dimensions were revealed and tested in cross-country studies, through an empirically confirmed scale (Warren et al., 2019). The role of category is another factor to examine (Liobikienė et al., 2016; Rezvani et al., 2018), with evidence of consumer response to vary accordingly across three distinct categories of sustainable products (Rahman, 2018). Furthermore, it seems appropriate to assume that most aspects of consumer behavior are culture bound (de Mooij and Hofstede, 2011). Based on those findings, we suggest that: P4: Brand Coolness moderate the relationship between Cognitive (4a), Normative (4b), Emotional factors (4c) and AGPB; P5: Product Category role moderate the relationship between Cognitive (5a), Normative (5b), Emotional factors (5c) and AGPB; P6: Cultural Values moderate the relationship between Cognitive (6a), Normative (6b), Emotional factors (6c) and AGPB. In summary, we argue that scientific knowledge and sustainable marketing fields would benefit from examining actual behavior, instead of purchase intentions, as a complex structure of barriers, motivations and intervening factors may be influencing (or blocking) the conversion of environmental concerns and attitudes into actions. For that effect, this study is unique because it explores an original set of topics, reviewing, and categorizing an unprecedented collection of suitable contributions from behavioral science, environmental and management literature. Based on the main theoretical arguments and empirical evidence available, we have uncovered the key elements which we believe can explain actual green purchase behavior. A new conceptual framework is proposed, which is - to be the best of our knowledge - the first to combine emotional, cognitive, and normative processes, while integrating new moderator effects often suggested in recent literature. We expect to assist researchers in conceptualizing different means of influencing sustainable consumer behavior and to stimulate future research, which can further explore and test the propositions here suggested, for a more comprehensive perspective on this domain. Moreover, new implications will be shared for the implementation of more effective managerial practices, communication strategies, social marketing campaigns and community interventions, for both business and non-for-profit organizations, useful for a diverse group of stakeholders such as policy makers, corporate and opinion leaders. Finally, we hope that our study can serve as a resource for both academic researchers and marketing practitioners seeking to further understand and advance the field of green marketing. Marketing plays a large role in influencing individual concerns and commitment with reducing impact on the environment, and thus can promote the achievement of customer needs, business goals and sustainable development at same time, without compromising among them, re-defining its own role, and embracing the new paradigm as opportunity for a more viable future.info:eu-repo/semantics/publishedVersio

Shaping a view on the influence of technologies on sustainable tourism

To date, tourism is the fastest growing industry globally, but one of the least developed in terms of environmentally sustainable practices. However, only a small portion of documents elaborate on how the introduction of new technologies can impact a more sustainable development route for tourism. This study’s objective is to provide an overview on literature state‐of‐the‐art related to sustainable tourism and technological innovations, offering insights for further advancing this domain. We employ a bibliometric analysis and a comprehensive review of 139 articles, collected from Web of Science and Scopus databases, for the purpose of: (i) exploring and discussing the most relevant contributions in the publication network: (ii) highlighting key issues and emerging topics; (iii) uncovering open questions for the future. Our findings reveal contradictory views on the risks and benefits of technology adoption. Artificial intelligence, internet of things, circular economy, big data, augmented and virtual reality emerge as major trends. Five work streams are identified and described, leading to a broader perspective on how technology can shape the future of sustainable tourism. Relevant theoretical and managerial implications are derived. Finally, a research agenda is proposed as guidance for future studies addressing the outcomes of digital disruption on sustainable tourism.info:eu-repo/semantics/publishedVersio

Experimental and theoretical evidences for the ice regime in planar artificial spin ices

In this work, we explore a kind of geometrical effect in the thermodynamics of artificial spin ices (ASI). In general, such artificial materials are athermal. Here, We demonstrate that geometrically driven dynamics in ASI can open up the panorama of exploring distinct ground states and thermally magnetic monopole excitations. It is shown that a particular ASI lattice will provide a richer thermodynamics with nanomagnet spins experiencing less restriction to flip precisely in a kind of rhombic lattice. This can be observed by analysis of only three types of rectangular artificial spin ices (RASI). Denoting the horizontal and vertical lattice spacings by a and b, respectively, then, a RASI material can be described by its aspect ratio $\gamma$=a/b. The rhombic lattice emerges when $\gamma$=$\sqrt{3}$. So, by comparing the impact of thermal effects on the spin flips in these three appropriate different RASI arrays, it is possible to find a system very close to the ice regime

Sistema de produção de leite em pastagem de Capim -Tanzânia: ações de transferência de tecnologia.

bitstream/CPAMN/20173/1/CT185.pd

Comportamento de cultivares de Cynodon no Piauí.

bitstream/CPAMN-2009-09/17159/1/CT146.pd

The solar wind in time – II. 3D stellar wind structure and radio emission

In this work, we simulate the evolution of the solar wind along its main-sequence lifetime and compute its thermal radio emission. To study the evolution of the solar wind, we use a sample of solar mass stars at different ages. All these stars have observationally reconstructed magnetic maps, which are incorporated in our 3D magnetohydrodynamic simulations of their winds. We show that angular-momentum loss and mass-loss rates decrease steadily on evolutionary time-scales, although they can vary in a magnetic cycle time-scale. Stellar winds are known to emit radiation in the form of thermal bremsstrahlung in the radio spectrum. To calculate the expected radio fluxes from these winds, we solve the radiative transfer equation numerically from first principles. We compute continuum spectra across the frequency range 100 MHz to 100 GHz and find maximum radio flux densities ranging from 0.05 to 2.2 μJy. At a frequency of 1 GHz and a normalized distance of d = 10 pc, the radio flux density follows 0.24 (Ω/Ω☉)0.9 (d/[10pc])-2μJy, where Ω is the rotation rate. This means that the best candidates for stellar wind observations in the radio regime are faster rotators within distances of 10 pc, such as κ1 Ceti (0.73 μJy) and χ1 Ori (2.2 μJy). These flux predictions provide a guide to observing solar-type stars across the frequency range 0.1-100 GHz in the future using the next generation of radio telescopes, such as ngVLA and Square Kilometre Array