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

Seeing colors in real scenes

Color perception in real conditions is determined by the spectral and spatial properties of objects and illumination. These properties are best evaluated by spectral imaging, a technique that records the reflecting spectral profile for each point of the scene. Using this technique on a set of natural scenes it was found that the color gamut expressed in the CIELAB color space is much smaller than the theoretical limits defined for the object colors. Moreover, the colors more frequent are those around the white point and their frequency of occurrence can be well described by a power law. Spatial variations of the spectral composition of the illumination across natural scenes were also quantified by placing small reflecting spheres in different locations of the scenes. The extent of these variations across scenes was found to be large and of the same order of magnitude as the variations of daylight along the day. These findings show that colors in nature are considerable constrained and that constancy mechanisms must be efficient over a wide range of stimuli variations to compensate for large natural variations of illumination

Tratamento de resíduos agroindustriais com uréia.

Bagaço de cana, casca de arroz e bagana de carnauba (Copernicia prunifera) foram tratados com uréia liquida, visando-se melhorar o seu valor nutritivo para utilização na alimentação animal. Foi utilizada a uréia liquida ( a 5%) na proporção de 100 l da solução para 100 kg de resíduo. Os materiais foram incubados em silos durante 10, 20 e 30 dias. 0 delineamento foi inteiramente casualisado, com três repetições. Os três resíduos tiveram seus percentuais de proteína aumentados pela amoniação, sendo que os aumentos foram relativamente maiores nos materiais de menor teor proteico. Antes da incubação os percentuais de proteína eram de. 2,78; 4,43 e 10,03, respectivamente em bagaço de cana, casca de arroz, e bagana de carnauba, aumentando para 5,20; 7,56 e 13,97% após dez dias de incubação. Os períodos de incubação superiores a 10 dias não tiveram efeito benéfico (P>0,05), ocorrendo até mesmo decréscimo nos percentuais de proteína, com o alongamento do período de incubação

Color diversity index : the effect of chromatic adaptation

Common descriptors of light quality fail to predict the chromatic diversity produced by the same illuminant in different contexts. The aim of this paper was to study the influence of the chromatic adaptation in the context of the development of the color diversity index, a new index capable of predicting illuminant-induced variations in several types of images. The spectral reflectance obtained from hyperspectral images of natural, indoor and artistic paintings, and the spectral reflectance of 1264 Munsell surfaces were converted into the CIELAB color space for each of the 55 CIE illuminants and 5 light sources tested. The influence of the CAT02 chromatic adaptation was estimated for each illuminant and for each scene. The CIELAB volume was estimated by the convex hull method and the number of discernible colors was estimated by segmenting the CIELAB color volume into unitary cubes and by counting the number of non-empty cubes. High correlation was found between the CIELAB volume occupied by the Munsell surfaces and the number of discernible colors and the CILEAB color volume of the colors in all images analyzed. The effects of the chromatic adaptation were marginal and did not change the overall result. These results indicate that the efficiency of the new illuminant chromatic diversity index is not influenced by chromatic adaptation

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