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- The effect of corporate strategic change on auditors’ predictions of going-concern opinions: the influence of crisis caused by the pandemicPublication . Arianpoor, Arash; Ramezanpour, Mohammad; ABDOLLAHI, AHMADThe purpose of this study is to investigate the impact of corporate strategic change (CSC) on the probability of an auditor’s going-concern opinion (GCOP) and the moderating role of COVID-19 on companies listed on the Tehran Stock Exchange. Design/methodology/approach – Information about 193 companies from 2014 to 2023 is examined. Considering that the dependent variable was binary, binary logistic regression analysis was used. Findings – The results of this study showed that CSC decreased the probability of a GCOP. Moreover, COVID-19 strengthened the adverse effects of CSC on the probability of an auditor’s opinion of going concern. The results also confirmed that CSC is exogenous in econometric models, indicating no omitted-variable bias or reverse causality. Originality/value – Audit failures in the past few years have highlighted a severe lack of early warning mechanisms and GCOPs. Although the existing models offer no recourse, the International Auditing and Assurance Standards Board’s (IAASB) direction in revising the International Standard on Auditing 570 shows that strategic cues can be powerful managerial signals, moving audit frameworks into managerial behavior. Moreover, signals under crisis and external shocks (e.g. COVID-19) can amplify the interpretive power of strategic behavior. This study empirically validates IAASB’s direction of IAASB. Through incorporating CSC and COVID-19, audit models can become more sensitive to proactive turnaround behaviors, thereby reducing systemic audit blind spots.
- Enhancement of the antioxidant response in gilthead seabream (Sparus aurata) juveniles through dietary algal supplementationPublication . Bolinhas, João Miguel Ramos; Teodósio, Rita; Engrola, SofiaFish in aquaculture are exposed to stressors such as handling and transport, which can lead to oxidative stress, compromising cellular integrity. Dietary intervention involving bioactive compounds can improve resilience and mitigate such damage. This study investigated the impact of algae-supplemented diets on the antioxidant and immune response of juvenile gilthead seabream following a short feeding trial and a subsequent stress challenge. A seven-day feeding trial was conducted using four diets: a control commercial-like diet (CTRL) and three alternatives supplemented with processed Tisochrysis lutea biomass (Tiso), Tisochrysis lutea biomass combined with Gelidium sp. extract (TisoG), and Tisochrysis lutea biomass and Skeletonema costatum extract (TisoS). Following the feeding trial, the challenge involved standardized events and infection with a pathogen (Photobacterium damselae subsp. piscicida) to assess if fish antioxidant responses were affected by the dietary treatments. Liver samples were collected post-feeding trial (Sampling 1-S1) and 6 hours post-infection (Sampling 2-S2) to evaluate growth performance, oxidative stress biomarkers, and expression of antioxidant and immune-related genes. Algae-supplemented diets had no negative effects on growth, feed efficiency, or survival. At S1, the TisoG group had significantly lower superoxide dismutase (SOD) activity and total antioxidant status (TAS) compared to other treatments. No differences were found in lipid peroxidation (LPO) or catalase (CAT) activity. At S2, SOD activity increased in Tiso, and TAS significantly increased in TisoG, with CAT and LPO remaining unaffected by diet. Gene expression at S1 showed no significant changes in oxidative stress markers, although igm was downregulated in Tiso and il-1β upregulated in TisoS. No differences were found in il-10, tnf-α, or hsp70. After S2, gpx1 was upregulated in CTRL and TisoG, sod2 was suppressed in TisoS, and nrf2 declined in all algae-fed groups. il-10 and tnf-α were highest in CTRL and significantly lower in TisoS. The Tisochrysis lutea and Gelidium extract diet was the most effective blend in enhancing antioxidant capacity and stress-related gene expression, especially after the challenge.
- Understanding air passengers' motivations and constraints for supporting sustainable air travelPublication . Siegl, Laura; Almeida, Cláudia Margarida Brito Ribeiro deThis work addresses the problem of achieving sustainable development in the aviation sector within the context of tourism. It combines a systematic literature review and a quantitative empirical study to provide a comprehensive analysis of the field. The review follows PRISMA 2020 guidelines and includes 48 peer-reviewed publications from 2011 to 2024, selected from Scopus, Web of Science, B-On, and Google Scholar. Eligible sources met strict quality, relevance, and methodological criteria and were assessed using a CASP-based checklist. The results allow for a characterisation of current research trends, highlighting a post-2020 shift toward optimisation models, value-based communication, and climate equity, alongside earlier work focused on behavioural factors. Despite growing academic attention, a gap remains between scholarly insight and practical application. Building on these findings, the empirical investigation analysed 432 air passenger survey responses using descriptive statistics, inferential analysis, Structural Equation Modelling (SEM), and cluster analysis. The study examined motivations and constraints influencing support for and willingness to pay for sustainable flights. Environmental concerns such as carbon reduction and intergenerational responsibility emerged as strong motivators, while cost, lack of awareness, and booking complexity posed significant barriers. SEM results show that sustainability awareness mediates the relationship between motivation, constraint, travel regularity, and willingness to pay. Frequent flyers, although more aware, showed lower spending inclination, suggesting cognitive dissonance. Demographic factors such as age and income had some influence, gender differences were not significant. Evidence from the study shows that the problems surrounding sustainable aviation require both behavioural and systemic solutions. The insights gained led to the presentation of interdisciplinary recommendations, emphasising targeted policy strategies, better communication, and non-price incentives to align consumer behaviour with climate goals.
- Production of nama seaweed (Caulerpa spp.) in an experimental lagoon cultivation setting and landbased system – Influence of cultivation depth and nutrient load on growth and morphologyPublication . Cordes, Aaron Johannes; Engelen, Aschwin; Kunzmann, AndreasWith the increasing impacts of climate change and declining fishery yields, interest in aquaculture is growing in Pacific Island Countries (PICs). One promising solution to produce nutritious and sustainable food without further exploiting the environment is the cultivation of seaweeds, which provide valuable biomass while simultaneously removing carbon dioxide and excess nutrients from the water. To offer fishers an economic alternative to high-value fishery products, seaweeds of the genus Caulerpa are particularly promising due to their comparatively high market price. In Fiji, these edible seaweeds, locally known as nama, are traditionally handharvested from shallow lagoon waters and reefs. However, rising demand has placed increasing pressure on natural stocks, making sustainable cultivation an important alternative. This study evaluated two cultivation approaches for nama. First a lagoon-based system using submerged trays at different depths, and secondly a land-based tank system with and without fertilizer supplementation. Because nama is highly sensitive to environmental parameters such as light intensity, nutrient availability, salinity, temperature, and hydrodynamics, the central aim was to determine which approach provides the most favorable conditions for optimal growth and desirable morphology. Replicated floating trays were deployed at four depths in lagoon waters, while land-based tanks were used to assess the effects of nutrient enrichment. Over a four-week period, relative growth rate (RGR), frond weight, ramuli density, and frond coloration were measured. To provide a benchmark for cultivated biomass, commercial nama sold in Fijian markets was also analyzed for the same parameters. The results suggest that nutrient limitation may be the primary bottleneck preventing successful cultivation in lagoon waters, as nama did not have access to sediment nutrient deposits. In contrast, fertilizer addition in the land-based system promoted growth but also caused pronounced morphological changes, resulting overall in a poor quality of the cultivated biomass. This study underscores the critical influence of nutrient availability on the successful cultivation of nama and can serve as a valuable proxy for future research. Particular attention should be directed toward the identification of the cultivated nama species and the composition of the applied fertilizer.
- Temperature-driven suitability shifts of sea lice species under climate change and the implications for salmon farmingPublication . Mackintosh, Amy Leigh; Assis, Jorge; Costello, Mark JohnSalmonids are the most valuable marine aquaculture family, worth approximately US$26.2 billion in 2022. However, the industry’s economic value is threatened by sea lice infestations, which can cause production losses and require expensive treatments to control. Climate change is driving distribution shifts in many marine species, including a potential poleward movement for several parasites. Currently, only the distribution response of the Chilean sea louse Caligus rogercresseyi has been examined under climate change conditions, while other harmful sea lice species remain unassessed. Here, we use a maximum entropy model to project the current and future thermal suitability of Lepeophtheirus salmonis, C. elongatus, and C. rogercresseyi under 3 climate change scenarios: SSP1-1.9, SSP3-7.0, and SSP5-8.5. The species’ thermal niches are similar, with preferred mean temperature ranges of 7.1 to 11.1°C for L. salmonis, 6.8 to 11.9°C for C. elongatus, and 11.0 to 12.8°C for C. rogercresseyi. Thermal suitability for all 3 species shifts and intensifies polewards under progressively warmer climate scenarios. As ocean warming also facilitates poleward range shifts of many salmonid species, the overlap in host and parasite distributions indicates that salmon aquaculture at higher latitudes could face increasing lice infestations and associated challenges.