Search Results (3,345)

In southern white rhinoceroses (Ceratotherium simum simum), pant calls are well-studied contact vocalisations, whereas the function of frequently emitted snorts remains unclear. We conducted playback experiments with 15 rhinoceroses at three European zoos. The first experiment tested responses to conspecific versus heterospecific snorts, comparing pulsed and non-pulsed acoustic structures. The second experiment contrasted conspecific snorts with conspecific pants from males differing in age and faecal testosterone metabolite (fTM) levels. Behavioural responses—including body orientation, approach toward loudspeaker, locomotion, and vocalisations—were analysed. Snorts, regardless of sender species or pulsation, elicited uniformly low-intensity responses, suggesting limited communicative function. In contrast, pants evoked significantly stronger responses depending on sex and group setting. While males showed increased locomotion, females vocalised more, reflecting the species’ social dynamics. Individuals tested alone displayed overall heightened vigilance and vocal activity compared to those tested in pairs, emphasising the role of social context. No evidence was found for discrimination between pant calls differing in fTM levels. Our findings reinforce the communicative relevance of pants in conveying social cues while indicating that snorts may either lack species-specific acoustic markers or not be socially salient. Playback experiments thus appear as valuable tools for assessing acoustic communication in zoo-housed mammals. Full article

Hydrogels comprise three-dimensional networks of hydrophilic polymers and have attracted considerable interest in various sectors, including the biomedical, pharmaceutical, agricultural, and food industries. These materials offer significant benefits for food packaging applications, such as high mechanical strength and excellent water absorption capacity, thereby contributing to the extension of product shelf life. Therefore, the aim of this study is to compare the performance of citric acid and glutaraldehyde as crosslinking agents in gelatine-based hydrogels reinforced with cellulose nanocrystals (CNC), contributing to the development of safe and environmentally responsible materials. The hydrogels were prepared using the casting method and characterised in terms of their physical, mechanical, and structural properties. The results indicated that hydrogels crosslinked with glutaraldehyde exhibited higher opacity, lower transparency, and greater mechanical strength, whereas those crosslinked with citric acid demonstrated improved clarity, reduced water permeability, and enhanced swelling capacity. The incorporation of CNC further improved mechanical strength, reduced weight loss, and altered both surface homogeneity and optical properties. Microstructural results obtained by SEM were consistent with the mechanical properties evaluated (TS, %E, and EM). The Gel-ca hydrogel displayed the highest elongation value (98%), reflecting better cohesion within the polymeric matrix. In contrast, films incorporating CNC exhibited greater roughness and cracking, which correlated with increased rigidity and mechanical strength, as evidenced by the high Young’s modulus (420 MPa in Gel-ga-CNC2). These findings suggest that the heterogeneity and porosity induced by CNC limit the mobility of polymer chains, resulting in less flexible and more rigid structures. Additionally, the DSC analysis revealed that gelatine hydrogels did not exhibit a well-defined Tg, due to the predominance of crystalline domains. Systems crosslinked with citric acid showed greater thermal stability (higher Tm and ΔH_m values), while those crosslinked with glutaraldehyde, although mechanically stronger, exhibited lower thermal stability. These results confirm the decisive effect of the crosslinking agent and CNC incorporation on the structural and thermal behaviour of hydrogels. In this context, the application of hydrogels in packaged products represents an eco-friendly alternative that enhances product presentation. This research supports the reduction in plastic consumption whilst promoting the principles of a circular economy and facilitating the development of materials with lower environmental impact. Full article

Accurate evaluation of subgrade behaviour under dynamic loading is essential for the long-term performance of transport infrastructure. While the Light Weight Deflectometer (LWD) is commonly used to assess subgrade stiffness, it provides only a single stiffness value and may not fully capture the time-dependent response of soil. This study presents an image-based vision system developed to monitor soil surface displacements during loading, enabling more detailed analysis of dynamic behaviour. The system incorporates high-speed cameras and MATLAB-based computer vision algorithms to track vertical movement of the plate during impact. Laboratory and field experiments were conducted to evaluate the system’s performance, with results compared directly to those from the LWD. A strong correlation was observed (R² = 0.9901), with differences between the two methods ranging from 0.8% to 13%, confirming the accuracy of the vision-based measurements despite the limited dataset. The findings highlight the system’s potential as a practical and cost-effective tool for enhancing subgrade assessment, particularly in applications requiring improved understanding of ground response under repeated or transient loading. Full article

The subject of this paper is the computational homogenisation and identification of heterogeneous materials in the form of auxetic structures made of materials with nonlinear characteristics. It is assumed that some of the material and topological parameters of the auxetic structures are uncertain and are modelled as interval numbers. Directed interval arithmetic is used to minimise the width of the resulting intervals. The finite element method is employed to solve the boundary value problem, and artificial neural network response surfaces are utilised to reduce the computational effort. In order to solve the identification task, the Pareto approach is adopted, and a multi-objective evolutionary algorithm is used as the global optimisation method. The results obtained from computational homogenisation under uncertainty demonstrate the efficacy of the proposed methodology in capturing material behaviour, thereby underscoring the significance of incorporating uncertainty into material properties. The identification results demonstrate the successful identification of material parameters at the microscopic scale from macroscopic data involving the interval description of the process of deformation of auxetic structures in a nonlinear regime. Full article

This study evaluated the effects of including 0, 150, 300, 450, and 600 g/kg of dry matter (DM) of spineless cactus (SC; Nopalea cochenillifera Salm-Dyck) plus urea and ammonium sulphate (UAS) (9:1), replacing Tifton-85 hay (Cynodon spp. cv. Tifton 85), on nutrient intake and digestibility, feeding behaviour, water intake, and rumen dynamics. Five rumen-fistulated and cannulated crossbred wethers were randomly assigned in a 5 × 5 Latin square design. A roughage:concentrate ratio of 70:30 was supplied. Organic matter (OM) and metabolisable energy (ME) intakes showed quadratic responses (p < 0.05), with maximum values of 1157 g/day and 14.50 MJ/day estimated at SC+UAS levels of 364 and 410 g/kg DM, respectively. Apparent digestibilities of DM, OM, and non-fibre carbohydrates, as well as water excretion in faeces and degradation rate of DM, increased with SC+UAS inclusion (p < 0.05). Indigestible neutral detergent fibre (NDF) intake, feeding and rumination times, voluntary water intake, NDF degradation and passage rates, as well as the indigestible NDF passage rate, decreased with SC+UAS inclusion (p < 0.05). In wethers’ diets with a roughage:concentrate ratio of 70:30, a roughage combination of SC+UAS and Tifton-85 hay in a 41:29 ratio is recommended to maximise ME intake. Full article

Difference in Differences (DiD) is a useful statistical technique employed by researchers to estimate the effects of exogenous events on the outcome of some response variables in random samples of treated units (i.e., units exposed to the event) ideally drawn from an infinite population. The term “effect” should be understood as the discrepancy between the post-event realisation of the response and the hypothetical realisation of that same outcome for the same treated units in the absence of the event. This theoretical discrepancy is clearly unobservable. To circumvent the implicit missing variable problem, DiD methods utilise the realisations of the response variable observed in comparable random samples of untreated units. The latter are samples of units drawn from the same population, but they are not exposed to the event under investigation. They function as the control or comparison group and serve as proxies for the non-existent untreated realisations of the responses in treated units during post-treatment periods. In summary, the DiD model posits that, in the absence of intervention and under specific conditions, treated units would exhibit behaviours that are indistinguishable from those of control or untreated units during the post-treatment periods. For the purpose of estimation, the method employs a combination of before–after and treatment–control group comparisons. The event that affects the response variables is referred to as “treatment.” However, it could also be referred to as “causal factor” to emphasise that, in the DiD approach, the objective is not to estimate a mere statistical association among variables. This review introduces the DiD techniques for researchers in economics, public policy, health research, management, environmental analysis, and other fields. It commences with the rudimentary methods employed to estimate the so-called Average Treatment Effect upon Treated (ATET) in a two-period and two-group case and subsequently addresses numerous issues that arise in a multi-unit and multi-period context. A particular focus is placed on the statistical assumptions necessary for a precise delineation of the identification process of the cause–effect relationship in the multi-period case. These assumptions include the parallel trend hypothesis, the no-anticipation assumption, and the SUTVA assumption. In the multi-period case, both the homogeneous and heterogeneous scenarios are taken into consideration. The homogeneous scenario refers to the situation in which the treated units are initially treated in the same periods. In contrast, the heterogeneous scenario involves the treatment of treated units in different periods. A portion of the presentation will be allocated to the developments associated with the DiD techniques that can be employed in the context of data clustering or spatio-temporal dependence. The present review includes a concise exposition of some policy-oriented papers that incorporate applications of DiD. The areas of focus encompass income taxation, migration, regulation, and environmental management. Full article

Background: Public discourse on social media plays an increasingly influential role in shaping health-related perceptions and behaviours. Individuals share experiences, concerns, and opinions beyond clinical settings around different issues. X (formerly Twitter) provides a unique lens through which to examine how different treatments are perceived, used, and debated across diverse communities over time. Objective: The study aims to (a) identify the types of ADHD medications mentioned in posts, depending on language and user type; (b) evaluate the popularity of content related to these medications, considering language and user type; (c) analyse temporal changes in the frequency of mentions between 2006 and 2022; and (d) examine the distribution of tweets across different content categories. By addressing these objectives, this study provides insights into public perceptions of ADHD medications, which may help healthcare professionals better understand online discussions and improve their communication with patients, facilitating more informed treatment decisions. Methods: An observational study was conducted analysing 254,952 tweets in Spanish and English about ADHD medications from January 2006 to December 2022. Content analysis combined inductive and deductive approaches to develop a categorisation codebook. BERTWEET and BETO models were used for machine learning classification of English and Spanish tweets, respectively. Descriptive statistical analysis was performed. Results: Overall, stimulant medications were posted more frequently and received higher engagement than non-stimulant medications. Methylphenidate, dextroamphetamine, and atomoxetine were the most commonly mentioned medications, especially by patients, who emerged as the most active users among the English tweets. Regarding medical content, tweets in English contained more than twice the number of mentions of inappropriate use compared to those in Spanish. There was a high content of online medication requests and offers in both languages. Conclusions: In this study, conducted on X, discussions on ADHD medications highlighted concerns about misuse, adherence, and trivialisation, with clear differences between English and Spanish tweets regarding focus and type of user participation. These findings suggest that monitoring social media can provide early signals about emerging trends, helping clinicians address misconceptions during consultations and informing public health strategies aimed at the safer and more responsible use of ADHD medications. Full article

Cognitive diagnosis models (CDMs) assess the proficiency of examinees in specific skills. Online education has increased the amount of data that is available on the response behaviour of examinees. Traditional CDMs determine the state of skills by modelling information on item response results and ignoring vital response time information. In this study, a CDM, named RT-CDM, which models the condition dependence between response time and response accuracy on the speed-accuracy exchange criterion, is proposed. The model’s continuous latent trait function and response time function, used for more precise cognitive analyses, makes it a tractable, interpretable skill diagnosis model. The Markov chain Monte Carlo algorithm is used to estimate the parameters of the RT-CDM. We evaluate RT-CDM through controlled simulations and three real datasets—PISA 2015 computer-based mathematics, EdNet-KT1, and MATH—against multiple baselines, including classical CDMs (e.g., DINA/IRT), RT-extended IRT and joint models (e.g., 4P-IRT, JRT-DINA), and neural CDMs (e.g., NCD, ICD, MFNCD). Across datasets, RT-CDM consistently achieves superior predictive performance, demonstrates stable parameter recovery in simulations, and delivers stronger diagnostic interpretability by leveraging RT alongside RA. Full article

Background/Objectives: This study evaluated the psychometric properties and correlates of the Screen for Disordered Eating (SDE) in the Chinese context. Eating and body image in Asian cultures differed from those in the Western context, elevating its importance in testing the validity of SDE in the Chinese context. Methods: The reliability, validity and correlates of the SDE were examined in a sample of 766 university students in Taiwan. Results: Convergent validity of the Chinese version of the SDE was demonstrated with high correlation (r = 0.664, p < 0.001) and satisfactory consistency (κ = 0.413, p < 0.001) with the Sick, Control, One Fat, and Food (SCOFF) questionnaire. Substantial factor loadings were suggested, with 52% of the variance in item responses, especially for SDE4 and SDE5. Significant correlates of disordered eating were found with sex, depressive symptoms, anxiety symptoms, and experiences of childhood trauma. Conclusions: The SDE is a reliable and valid screening instrument for disordered eating. Health and social care practitioners can utilise the SDE to screen for disordered eating behaviours in the Chinese context, so that timely interventions can be provided. Full article

Understanding the nature of monetary and fiscal policy interactions has gained more importance over the years, especially within the context of the global financial crisis and the recent COVID-19 pandemic. This study uses a Time-Varying Parameter Vector Autoregressive (TVP-VAR) model and a Markov Switching Dynamic Regression (MSDR) framework to explore the dynamics of monetary–fiscal policy interactions in South Africa. The analysis employs time series data from 1994 to 2023 and tests the dynamic response of key macroeconomic variables to positive monetary and fiscal policy shocks. Furthermore, the MSDR framework is utilised to analyse how policy behaviour evolves during regime change. The TVP-VAR results show that fiscal expansions led to a positive response in GDP over time, a stable interest rate reaction post-COVID-19, and a consistently negative CPI response, contradicting conventional theory. The MSDR analysis reveals a dominant regime where monetary policy is active and fiscal policy is passive, with a positive interaction between interest rates and government spending, likely reflecting South Africa’s high debt environment. These findings underscore the importance of understanding policy interactions’ landscape to inform policy decisions better and minimise sub-optimal policy outcomes. Full article

The rollout of COVID-19 vaccines marked a turning point in pandemic control, yet vaccine hesitancy emerged as a significant obstacle in sub-Saharan Africa (SSA). The study aims to investigate socio-behavioural drivers of vaccine hesitancy in three high-resistance countries: the Republic of Congo, the Democratic Republic of the Congo, and the Republic of Guinea-Bissau. By employing a qualitative ethnographic design, in the period from April to October 2022, the study enrolled 752 participants in semi-structured in-depth interviews and focus group discussions, involving community leaders, women’s leaders, healthcare providers, traditional practitioners, traditional leaders, drivers, and youth leaders, ensuring diverse perspectives. Findings indicate that vaccine hesitancy is fluid and contextual with three principal drivers: (1) denial of COVID-19’s existence, often reinforced by scepticism among healthcare providers and the belief that the disease is foreign or a governmental scheme for financial gain; (2) misinformation, including rumours about vaccine incompatibility with certain foods, and fears of sterility and witchcraft; (3) a firm reliance on traditional medicine, seen as effective alternative to biomedical interventions. Vaccine hesitancy can only be addressed through culturally responsive, multisectoral approaches centred on community dialogue, improved communication, and the integration of trusted networks. Without inclusive strategies, resistance will undermine pandemic response and future health interventions in SSA. Full article

The bioeconomy has been discussed as a key strategy for addressing sustainability challenges, particularly regarding the transition from fossil-based to bio-based systems, in numerous national and supranational strategies and policy documents related to the bioeconomy. However, public understanding of and engagement with the bioeconomy remains limited. This is partly due to the bias of many bioeconomy strategies and policy documents towards technological solutions that tend to overlook the social, normative, and transformative dimensions of systemic change as well as the necessary knowledge. This opinion paper explores the potential of narratives as a means of communicating bioeconomy research in public policy, with the aim of addressing the communication gap between science, policy, and society. When applied in responsible and nuanced ways that acknowledge their embeddedness and context, bioeconomy (policy) narratives can support sensemaking for science communication, improve public understanding, facilitate stakeholder engagement and behavioural change. We argue that such narrative approaches can help to create narrative ‘boundary objects’ that can support more inclusive and participatory processes, enabling the co-creation of transformative knowledge for bioeconomy transitions with stakeholders as active participants. In summary, we highlight several opportunities, as well as limitations and implications, that could inform future work on bioeconomy narratives. Full article

Growing consumer interest in personal health and environmental sustainability has driven a significant number of companies to enter the organic food market. While this offers valuable opportunities, companies face substantial challenges in making marketing decisions which are aligned with the specific characteristics of this sector. This paper studies the impact of three external drivers—environmental customer pressure, environmental competitive intensity, and environmental regulatory pressure—on companies’ decision to adopt a dominant green positioning strategy within the Romanian organic food market. To this end, an online survey was conducted among 77 companies, including producers, processors, distributors, and retailers, all of which own an organic food brand. Partial Least Squares Structural Equation Modelling (PLS-SEM) was applied to assess the measurement model and test the hypothesised structural relationships. Our findings confirm that customer pressure plays a significant role in shaping green brand positioning decisions. Accordingly, companies must be responsive to consumer expectations, even in the absence of strict regulations in Romania’s organic food sector guiding organisational behaviour. Furthermore, competitive dynamics were also found to be vital, as evidenced by the positive and direct relationship between environmental competitive intensity and the strategic green positioning decision examined. Full article

This study explores how older Chinese migrants in London engage with climate change discourse using participatory co-design workshops. Although already practising sustainability behaviours such as recycling, this group faces significant barriers—particularly language difficulties and cultural differences—that limit their active participation in broader climate initiatives. The research addresses three key aspects: (1) identifying opportunities for sustainable practices within migrants’ daily routines; (2) understanding their influential roles within families and communities; and (3) examining their trusted sources and preferred channels for climate communication. Results highlight that family and community networks, combined with digital platforms (e.g., WeChat) and visually engaging materials, play essential roles in disseminating climate information. Participants expressed strong motivations rooted in intergenerational responsibility and economic benefits. The findings emphasise the necessity of inclusive and peer-led communication strategies that are attuned to older migrants’ linguistic preferences, media habits, and cultural values—underscoring their significant but often overlooked potential to meaningfully contribute to climate action. Full article

Adolescents’ perception and recognition of sexual harassment (SH) are shaped by several psychosocial variables, including gender norms, emotional responses, and ideological beliefs (such as sexism). This study specifically aimed to investigate the mediating roles of moral disengagement and emotional responses in the relationship between tolerance of SH and recognition of harassment scenarios, while considering gender as a moderator. The sample included 380 high-school students (55.3% female, 44.7% male), aged between 14 and 18 years (M_age = 15.71, SD_age = 0.87). No significant direct association was found between attitudes toward sexually harassing behaviour (TSHI) and recognition of potential harassing scenario (assessed by the Sexual Harassment Definitions Questionnaire—SHDO). However, TSHI was indirectly associated with SHDO through two distinct mediational pathways. On the one hand, higher tolerance of sexual harassment was associated with increased moral disengagement, which in turn was related to lower recognition of SH. On the other hand, it was associated with reduced negative emotional reactions, which were in turn associated with greater recognition of harassment. Additionally, gender differences emerged: females demonstrated greater ability to identify harassment scenarios and reported stronger negative emotional reactions. Overall, these findings highlight the role of psychosocial mechanisms in shaping adolescents’ recognition of harassment situations. Full article