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Laminar natural convection of nanofluids in a square cooled cavity enclosing a heated horizontal cylinder is studied numerically. This paper aims to investigate in what measure the nanoparticle size and average volume fraction, the cavity width, the cylinder diameter and position, the average temperature of the nanofluid and the temperature difference imposed between the cylinder and the cavity walls, affects the basic heat and fluid flow features, as well as the thermal performance of the nanofluid relative to that of the base liquid.

The four-equation system of the mass, momentum and energy transfer governing equations has been solved using a computational code incorporating three empirical correlations for the evaluation of the effective thermal conductivity, the effective dynamic viscosity and the coefficient of thermophoretic diffusion, all based on a high number of experimental data available in the literature. The SIMPLE-C algorithm has been used to handle the pressure-velocity coupling. Simulations have been performed using Al₂O₃ + H₂O, for different values of the average volume fraction of the suspended solid phase in the range 0-0.04, the diameter of the nanoparticles in the range 25-75 nm, the temperature difference imposed between the cylinder and the cavity walls in the range 5-20 K, the average nanofluid temperature in the range 300-330 K, the ratio between the cylinder diameter and the cavity width in the range 0.1-0.5 m, the ratio between the distance of the cylinder axis from the bottom wall and the cavity width in the range 0.2-0.8 and the ratio between the distance of the cylinder axis from the left sidewall and the cavity width in the range 0.2-0.5.

The main results obtained may be summarized as follows: the overall solid phase migration from hot to cold results in a cooperating solutal buoyancy force which tends to compensate the friction increase consequent to the viscosity growth due to the dispersion of the nanoparticles into the base fluid; the effect of the increased thermal conductivity consequent to the nanoparticle dispersion into the base fluid plays the major role in determining the heat transfer enhancement of the nanofluid, at least in the upper range of the investigated average temperatures; at high temperatures, the nanofluid heat transfer performance relative to that of the pure base liquid increases with increasing the average volume fraction of the suspended solid phase, whereas at low temperatures, it has a peak at an optimal particle loading; the relative heat transfer performance of the nanofluid increases notably with increasing the average temperature, and just moderately as the imposed temperature difference, the width of the cavity and the distance of the cylinder from the bottom of the cavity, are increased; the relative heat transfer performance of the nanofluid increases as the nanoparticle size, the cylinder diameter and the distance of the cylinder from the sidewall, are decreased; as a consequence of the local competition between the thermal and the solutal buoyancy forces, a periodic flow arises when the cylinder is located in the vicinity of one of the cooled walls of the enclosure.

Framed in this general background, a comprehensive numerical study on buoyancy-driven convection of alumina-water nanofluids inside a cooled square cavity containing a heated circular cylinder is executed by the way of a two-phase model based on the double-diffusive approach accounting for the effects of the Brownian diffusion and thermophoresis.

This paper aims to investigate numerically buoyancy-induced convection from a pair of differentially heated horizontal circular cylinders set side by side in a nanofluid-filled adiabatic square enclosure, inclined with respect to gravity so that the heated cylinder is located below the cooled one, using a two-phase model based on the double-diffusive approach assuming that the Brownian diffusion and thermophoresis are the only slip mechanisms by which the solid phase can develop a significant relative velocity with respect to the liquid phase.

The system of the governing equations of continuity, momentum and energy for the nanofluid, and continuity for the nanoparticles, is solved by a computational code based on the SIMPLE-C algorithm. Numerical simulations are performed for Al₂O₃ + H₂O nanofluids using the average volume fraction of the suspended solid phase, the tilting angle of the enclosure, the nanoparticle size, the average nanofluid temperature and the inter-cylinder spacing, as independent variables.

The main results obtained may be summarized as follows: at high temperatures, the nanofluid heat transfer performance relative to that of the pure base liquid increases with increasing the average volume fraction of the suspended solid phase, whereas at low temperatures it has a peak at an optimal particle loading; the relative heat transfer performance of the nanofluid has a peak at an optimal tilting angle of the enclosure; the relative heat transfer performance of the nanofluid increases notably as the average temperature is increased, and just moderately as inter-cylinder spacing is increased and the nanoparticle size is decreased.

The two-phase computational code used in the present study incorporates three empirical correlations for the evaluation of the effective thermal conductivity, the effective dynamic viscosity and the coefficient of thermophoretic diffusion, all based on a high number of literature experimental data.

Within the framework of EU policies and measures to develop a just and fair green energy transition model. This paper aims to offer valuable insights into a paramount concern not so well debated in the literature, i.e. the spatial variation of energy poverty.

This empirical analysis investigates the regional variation of energy poverty we draw on a sample of more than 300,000 Spanish households, extracted from the Spanish Household Budget Survey (HBS) for the period 2006–2022. To characterize the probability of a household finding itself in a situation of energy poverty the authors use a discrete choice univariate probit model.

The results confirm that energy poverty is a phenomenon that is asymmetrically distributed across Spain, and mainly occurs in un-densely populated regions. In addition, the findings demonstrate that the incidence of energy poverty drivers is highly heterogeneous across regions.

The paper ends with some recommendations for policymakers suggesting that countries need to design an energy poverty policy for the households that jointly pursue both a correct identification of vulnerable groups and a match with the type of measure to the characteristics of each region.

This study enhances previous research by considering the case of areas at a lower level of aggregation (i.e. on the NUTS two regions in Spain called autonomous communities) and offers the opportunity to tailor policies to those regions most in need. Furthermore, to provide a more realistic picture of the complex phenomenon of energy poverty, the authors use the information for the period 2006–2022 differentiating by economic micro-cycle. This timespan allows the authors to understand the dynamics of energy poverty in periods of economic crisis, including the effects of the 2008 crisis and the present global energy crisis.

The purpose of this paper is to investigate US lodging properties’ organizational employee‐retention initiatives and practices, and to examine the impact of those initiatives on employee turnover and retention.

Using the Directory of Hotel & Lodging Companies, a convenient sample group of 24 management companies are selected. A self‐administered mail survey instrument is developed to measure and test organizational initiatives and practices on employee turnover and retention. Using SPSS 16.0, two statistical tests are employed to test study hypotheses. Correlation analysis is used to identify the relationships between predictor and response variables. Likewise, regression analysis is used to examine the relationships between predictor and response variables hypothesizing that the effectiveness of practicing the human resource management organizational initiatives on management and non‐management retention and turnover will differ.

The findings reveal that Corporate Culture, Hiring and Promotions and Training practices influence non‐management employee retention. At the same time, Hiring and Promotion practices impact management retention, as well. Moreover, Organizational Mission, Goals and Direction, and Employee Recognition, Rewards and Compensation were found to positively reduce non‐management employee turnover.

Owing to the study methodology and the relatively low response rate, generalization of the study findings is limited. Future replication studies are recommended.

The findings will equip lodging organizations and industry professionals with the contemporary tools to proactively reduce employee turnover and for maintaining employee retention. This should have a positive impact on workforce productivity.

This study makes a major contribution to the relative influence of the practice of eight study‐defined organizational initiatives on turnover in lodging businesses.

The use of recommender systems is increasing on academic social media (ASM). However, distinguishing the elements that may be influenced and/or exert influence over content that is read and disseminated by researchers is difficult due to the opacity of the algorithms that filter information on ASM. In this article, the purpose of this paper is to investigate how algorithmic mediation through recommender systems in ResearchGate may uphold biases in scholarly communication.

The authors used a multi-method walkthrough approach including a patent analysis, an interface analysis and an inspection of the web page code.

The findings reveal how audience influences on the recommendations and demonstrate in practice the mutual shaping of the different elements interplaying within the platform (artefact, practices and arrangements). The authors show evidence of the mechanisms of selection, prioritization, datafication and profiling. The authors also substantiate how the algorithm reinforces the reputation of eminent researchers (a phenomenon called the Matthew effect). As part of defining a future agenda, we discuss the need for serendipity and algorithmic transparency.

Algorithms change constantly and are protected by commercial secrecy. Hence, this study was limited to the information that was accessible within a particular period. At the time of publication, the platform, its logic and its effects on the interface may have changed. Future studies might investigate other ASM using the same approach to distinguish potential patterns among platforms.

Contributes to reflect on algorithmic mediation and biases in scholarly communication potentially afforded by recommender algorithms. To the best of our knowledge, this is the first empirical study on automated mediation and biases in ASM.

This paper aims to reconstruct the process that led to the appropriation of history – of a particular historical period, the Renaissance – as an intangible asset in the promotion of Italian fashion on the international market after the Second World War.

The paper reconstructs the process that led to the appropriation of history – of a particular historical period, the Renaissance – as an intangible asset in the promotion of Italian fashion on the international market after the Second World War.

The successful debut of Italian fashion in the fifties can be explained through an intelligent marketing campaign which placed it directly in the centre of a well-known, appreciated, not to say indisputable, tradition of “good taste”: that of the Renaissance. Connecting Italian fashion with Renaissance Italy meant in fact introducing a kind of ante litteram guarantee of provenance – a “country branding” - recognized throughout the world, which, at the same time, evoked the splendour of a period in which Italian taste was a model to follow and imitate.

The studies on the history of the Italian fashion business have accepted the association of Italian fashion with Renaissance tradition as an element to be taken for granted, without inquiring into the historical legitimacy of such a coupling (either in the way in which it was produced or why it had such an important role). This paper dismantles the consistent rhetorical sedimentation with which the subject is encrusted and provides a new insight, showing that such continuity did not exist; on the contrary, it was the product of a marketing strategy.

The purpose of this paper is to emphasize the increasing importance of information and communication technologies (ICTs) in smart tourism destinations, in their integration in the activity of the tourism companies, and in their interaction with visitors/tourists. In summary, it is intended to evaluate in the city of Porto how the use of technology before, during and after the visit influences the tourist experience.

The authors empirically investigate the importance of using ICTs during tourism experience, assess the access/availability of ICT at the destination and its importance in tourist’s decisions. It is analyzed if the applications and/or information available on the internet are important and positively influence the tourism experience in Porto, that is, the degree of tourist satisfaction. The empirical evidence is based on a quantitative analysis, using a data set involving 423 tourists in the city of Porto.

The importance of the internet access at the destination, especially in places like airports and hotels, since most tourists are primarily using their mobile devices and computers during the trip, and the existing information technologies available in the destination (internet, smartphones or other mobile devices and applications) are considered very important in explaining tourists’ experience.

This study identifies the strengths and weaknesses of the technological strategies, providing useful information for destination management, discussing innovation in tourism, and proposing a framework that empirically evaluates how technological components used in smart tourism destinations can improve tourists’ experiences.

The main occupational safety measure in factories is monitoring workers exposed to various types of contaminations. The main environmental concern of governments about copper industries is emission of dust, metals, metal compounds and volatile organic compounds in air. The purpose of this paper is to evaluate the immune system status of workers in a copper concentration factory in Iran by placing the emphasis on oxidative stress biomarkers.

A comparative cross-sectional study was performed on 40 workers of the copper concentration factory and 40 unexposed individuals. White blood cell count, plasma interleukin 2 and 4, oxidative burst of neutrophils, oxidative damages of DNA and RNA, lipid and protein, total antioxidant capacity of plasma, and antioxidant enzymes activities were measured.

A significant decrease in the white blood cell count and interleukin 2 and an increase in the interleukin 4 were observed in the workers and these changes represented the possibility of inflammation and weakening of the immune system. The elevation of oxidative damages, total antioxidant capacity and the activity of antioxidant enzymes are indicative of the change in oxidative stress status.

The oxidative stress induction and immune system changes might be useful biomarkers in screening and surveillance for occupational hazard. More studies are needed to find out the type and the concentration of pollutants and to evaluate the protective effects of natural antioxidants.

Edible insects have emerged as a promising inexpensive option to address malnutrition among vulnerable groups in the world. However, it is not clear whether including insects in diets can improve health outcomes. This paper aimed to investigate the impact of edible insect consumption on human health.

A search was conducted in PubMed Central, BioMed Central, Plosone, Cochrane, Google Scholar, Google Search and bibliographies for all human studies on the impact of edible insect consumption on human health published from January 1990 to April 2018.

Twelve studies met the inclusion criteria. Consumption of cereals fortified with edible insects improved iron status and growth in infants and led to the development of life threatening anaphylactic reactions in sensitive people.

Edible insects are nutritious. More rigorous studies are needed to confirm nutrient bioavailability, acceptability and nutritional benefits in humans.

This review shows that the utilization of edible insects as food promotes desirable health outcomes, but caution must be taken to prevent allergic reactions in some cases.

Prisons can be epicentres of infectious diseases. However, empirical evidence on the impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in prison is still scarce. This study aims to estimate the seroprevalence rates of anti-SARS-CoV-2 in the largest and most crowded Swiss prison and compare them with the seroprevalence rate in the general population.

A cross-sectional study was conducted in June 2020, one month after the first wave of SARS-CoV-2 in Switzerland. Groups included: people living in detention (PLDs) detained before the beginning of the pandemic (n = 116), PLDs incarcerated after the beginning of the pandemic (n = 61), prison staff and prison healthcare workers (n = 227) and a sample from the general population in the same time period (n = 3,404). The authors assessed anti-SARS-CoV-2 IgG antibodies.

PLDs who were incarcerated before the beginning of the pandemic had a significantly lower seroprevalence rate [0.9%, confidence interval (CI)95%: 0.1%–5.9%] compared to the general population (6.3%, CI 95%: 5.6–7.3%) (p = 0.041). The differences between PLDs who were incarcerated before and other groups were marginally significant (PLDs incarcerated after the beginning of the pandemic: 6.6%, CI 95%: 2.5%–16.6%, p = 0.063; prison staff CI 95%: 4.8%, 2.7%–8.6%, p = 0.093). The seroprevalence of prison staff was only slightly and non-significantly lower than that of the general population.

During the first wave, despite overcrowding and interaction with the community, the prison was not a hotspot of SARS-CoV-2 infection. Preventive measures probably helped avoiding clusters of infection. The authors suggest that preventive measures that impact social welfare could be relaxed when overall circulation in the community is low to prevent the negative impact of isolation.