Career expectations contribute to job satisfaction and worker persistence. The tourism industry is characterized by high staff turnover. The industry was decimated by the COVID-19 pandemic causing widespread unemployment and transforming working conditions, while radically altering educational conditions for hospitality and tourism students. We assessed how the pandemic influenced students' expectations, comparing undergraduate opinions before and during the pandemic. While Pandemic-Students were more pessimistic about working conditions, they revealed an increased desire to provide personal interactive service and a greater tendency towards entrepreneurialism. These results contrast with previous research; highlighting students' resilience and suggesting a positive vision of pandemic-related opportunities.

As a fast-growing food production industry, aquaculture is dealing with the need for intensification due to the global increasing demand for fish products. However, this also implies the use of more sustainable practices to reduce negative environmental impacts currently associated with this industry, including the use of wild resources, destruction of natural ecosystems, eutrophication of effluent receiving bodies, impacts due to inadequate medication practices, among others. Using multi-species systems, such as integrated multi-trophic aquaculture, allows to produce economically important species while reducing some of these aquaculture concerns, through biomitigation of aquaculture wastes and reduction of diseases outbreaks, for example. Applying mathematical models to these systems is crucial to control and understand the interactions between species, maximizing productivity, with important environmental and economic benefits. Here, the application of some equations and models available in the literature, regarding basic parameters, is discussed – population dynamics, growth, waste production, and filtering rate – when considering the description and optimization of a theoretical integrated multi-trophic aquaculture operation composed by three trophic levels.

The photographic practice is an essential element in the tourist experience and DMO is no longer the main responsible for the visual content available on a destination. UGC role in destination image construction is getting more influential. The approximation of the projected and perceived image can lead to successful campaigns and tourists’ positive feedback. At this case study we aim to compare DMO and Tourists’ photos by its similarity/dissimilarity among different attributes. Content analysis is being used to segment the photos into different categories and compare them by the frequency. It was concluded in this case study that beside the similarity of the main categories, there are some subcategories’ dissimilarities that might be worked in order to help DMO achieve better results on social media and to approximate tourists preferences to their visual marketing strategy.

This study focusing on local food restaurants aims to evaluate the variables that influence consumers' restaurant selection, and the most important variables that need to be addressed by those establishment managers. With this assessment it will be possible to structure different strategies which enterprises can resort to in order to obtain management advantages.A management model based on selection variables and how restaurants can influence the choice process is proposed in this article. Therefore, it is possible to maximise profit and the number of customers, to increase service quality, to create new services and dishes, to define strategic promotion plans, and to produce effective corrective measures.

The growing demand for fish products and the dwindling productivity of marine fish stocks due to the overexploitation of fisheries place the aquaculture industry as a key contributor to the global fish supply. The intensive development of aquaculture has raised a range of environmental concerns such as effluent discharge, excessive use of resources and dependence on commercial feed. In this context, the development of sustainable aquaculture systems is becoming the cornerstone for long-term aquaculture expansion, and to achieve environmental sustainability. Integrated multitrophic aquaculture (IMTA) is regarded as a suitable approach to limit aquaculture nutrients and organic matter outputs through biomitigation. The cocultured species are used as biofilters, and each level has its own independent commercial value, providing both economic and environmental sustainability. Here, environmental issues of aquaculture and the current status of IMTA are reviewed and its future prospects discussed. Also, the opportunities to expand this systems' complexity with increased added-value and trophic levels are introduced.

Integrated multi-trophic aquaculture (IMTA) is regarded as a suitable approach to limit aquaculture nutrients and organic matter outputs through biomitigation. Here, species from different trophic or nutritional levels are connected through water transfer. The co-cultured species are used as biofilters, and each level has its own independent commercial value, providing both economic and environmental sustainability. In order to better understand and optimize aquaculture production systems, dynamic modelling has been developed towards the use of models for analysis and simulation of aquacultures. Several models available determine the carrying capacity of farms and the environmental effects of bivalve and fish aquaculture. Also, in the last two decades, modelling strategies have been designed in order to predict the dispersion and deposition of organic fish farm waste, usually using the mean settling velocity of faeces and feed pellets. Cultured organisms growth, effects of light and temperature on algae growth, retention of suspended solids, biodegradation of nitrogen and wastewater treatment are examples of other modelled parameters in aquaculture. Most modelling equations have been developed for monocultures, despite the increasing importance of multi-species systems, such as polyculture and IMTA systems. The main reason for the development of multi-species models is to maximize the production and optimize species combinations in order to reduce the environmental impacts of aquaculture. Some multi-species system models are available, including from the polyculture of different species of bivalves with fish to more complex systems with four trophic levels. These can incorporate ecosystem models and use dynamic energy budgets for each trophic group. In the proposed IMTA system, the bioremediation potential of the marine seaweed Gracilaria vermiculophylla (nutrient removal performance) and the Mediterranean filter-feeding polychaete Sabella spallanzanii (capacity to filter, accumulate and remove particles and bacterial groups) co-cultured with the highly valued marine fish Diplodus sargus is assessed. This study includes to development of a model to mathematically describe the proposed IMTA system. The main focus of this model is optimize species combinations and yields from each trophic level. Such a mathematical description of the system also opens the possibility of developing simulators to study the purposed system, comparing it under different conditions.

An h-set is a nonempty compact subset of the Euclidean n-space which supports a finite Radon measure for which the measure of balls centered on the subset is essentially given by the image of their radius by a suitable function h. In most cases of interest such a subset has Lebesgue measure zero and has a fractal structure.Let Omega be a bounded C-infinity domain in R-n with Gamma subset of Omega. LetB := (-Delta)(-1) circle tr(Gamma),where (-Delta)(-1) the inverse of the Dirichlet Laplacian in Omega and tr(Gamma) is, say, a trace type operator. The operator B, acting in convenient function spaces in Omega, is studied. Estimations for the eigenvalues of B are presented, and generally shown to be dependent on h, and the smoothness of the associated eigenfunctions is discussed. Some results on Besov spaces of generalised smoothness on R-n and on domains which were obtained in the course of this work are also presented, namely pointwise multipliers, the existence of a universal extension operator, interpolation with function parameter and mapping properties of the Dirichlet Laplacian. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

An h-set is a non-empty compact subset of the Euclidean n-space which supports a finite Radon measure for which the measure of balls centered on the subset is essentially given by the image of their radius by a suitable function h. In most cases of interest such a subset has Lebesgue measure zero and has a fractal structure.We prove the existence of solutions for the so-called fractal Dirichlet problem for such h-sets.The "construction" of the solutions is based on the consideration of complete o.n. systems for convenient function spaces on the fractals. These systems are obtained combining properties of traces with integral representations (obtained with the help of Green's functions) for the so-called fractal Laplacian.

An h-space is a compact set with respect to a quasi-metric and endowed with a Borel measure such that the measure of a ball of radius r is equivalent to h(r), for some function h. Applying an approach introduced by Triebel in [29] we define Besov spaces of generalised smoothness on h-spaces. We describe the techniques and tools used in this construction, namely snowflaked transforms and charts. This approach relies on using what is known for function spaces on some fractal sets, which are themselves defined as traces of convenient function spaces on R-n. It has turned out to be important to obtain new properties and characterisations for the elements of these spaces, for example, to guarantee the independence of the charts used. So we also present results for Besov spaces of generalised smoothness on R-n and some special fractal sets, namely characterisations by differences and a homogeneity property (on R-n) and non-smooth atomic decompositions.

A homogeneity property for some Besov spacesBp,qsis proved. An analogous property for someFp,qsspaces is already known.