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To describe water absorption by the rice grains over time, diffusion and empirical models were used. Also, an optimization software was developed in this study to determine parameters and their uncertainties for the diffusion models (LS Optimizer, for partial differential equations). Parameters (and their uncertainties) for empirical models were determined by LAB Fit Curve Fitting Software.

Heat and mass diffusion phenomena are found in various processes of technological interest, including pasteurization, drying and water immersion of agricultural products, among others. The objective of this work was to study the process of water absorption by rice grains with and without husk, using diffusion and empirical models to describe the absorption kinetics. Rice grains were immersed (approximately 10 g for each experiment) in drinking water maintained at constant temperatures of 28, 40 and 50 C. In the experiments, the water contents absorbed by rice grains over time were obtained by the gravimetric method.

Among empirical models, Peleg was the most satisfactory to describe the kinetics of water absorption by rice without husk, while the Silva et alii model had the best statistical indicators for rice with husk. It was also verified that a diffusion model with boundary condition of the first kind showed the best (or equivalent) results in the description of all processes of kinetics of water absorption by rice grains, with and without husk. For grains without husk, the effective mass diffusivities were (1.186 ± 0.045) × 10⁻⁹, (1.312 ± 0.024) × 10⁻⁹ and (2.133 ± 0.028) × 10⁻⁹ m² min⁻¹, for the immersion temperatures of 28, 40 and 50C, respectively. For grains with husk, diffusivities were (0.675 ± 0.011) × 10⁻⁹ and (1.269 ± 0.017) × 10⁻⁹ m² min⁻¹, for temperatures of 28 and 50 C, respectively.

This work developed a solver for the diffusion equation in cylindrical geometry and presented the LS Optimizer software developed to determine differential equation parameters through experimental data sets.

This chapter reviews developments in the intellectual and activist work of African feminists and gender scholars over the past two decades. African feminists and gender scholar activists have broken with dominant epistemologies to frame their own sites of knowledge production and feminist identity, reflecting shifting conditions in local and global contexts. The knowledge they generate is rooted in a tradition of scholarship, activism, and engagements with state institutions and with transnational and regional feminist movements. I discuss (1) contexts in which African feminist standpoints have emerged over the past 20 years, (2) developments in women and gender studies programs, and (3) ways in which African feminist scholars in the continent and diaspora have stimulated intellectual engagement and activism through feminist research and publishing, collaborative scholarship, influencing policy, and new forms of activism.

In collaborative settings, such as research and development projects, obtaining the maximum benefit from knowledge management systems depends on the ability of the different partners to understand the conceptualisation underlying the system’s knowledge organisation. This paper aims to show how information/knowledge organisation in a multi-organisation project can be made more effective if the domain experts are involved in the specification of the systems semantic structure. A particular aspect is further studied: the role of conceptual relations in the process of collaborative development of such structures.

An action-research approach was adopted, framed by a socio-semantic stance. A collaborative conceptual modelling platform was used to support the members of a research and development project in the process of developing a lightweight ontology aiming at reorganising all the project information in a wiki system. Data collection was carried out by means of participant observation, interviews and a questionnaire.

The approach to solve the content organisation problem revealed to be effective both in the result and the process. It resulted in a better-organised system, enabling more efficient project information retrieval. The collaborative development of the lightweight ontology embodied, in fact, a learning process, leading to a shared conceptualisation. The research results point to the importance of the elicitation of conceptual relations for structuring the project’s knowledge. These results are important for the design of methods and tools to support the collaborative development of conceptual models.

This paper studies the social process leading to a shared conceptualisation, a subject that has not been sufficiently researched. This case study provides evidence about the importance of the early phases of the construction of ontologies, mainly if domain experts are deeply involved, supported by appropriated tools and guided by well-structured processes.

This paper introduces a generic performance measurement methodology for identifying and dimensioning the user requirements of laboratory information systems with a view to evaluating and improving their overall user satisfaction. The dynamic Web‐based laboratory information system (known as IntraMEL) for the Manufacturing Engineering Laboratories (MEL) in the City University of Hong Kong is used as a case study for formulating, testing and implementing the methodology. The proposed model takes an analytical approach to assess the performance of an information system using psychometric concepts. Through the experience gained from applying the methodology on IntraMEL, a set of performance evaluation guidelines can be established. These evaluation guidelines will be applicable to the information systems in other laboratories and service centres.

The purpose of this study is to assess the effect of a diet added with taro (Colocasia esculenta) flour on the body composition of rats.

Weanling male rats were divided into Control (n = 11) and experimental groups (Taro, n = 12); experimental rats were fed on taro for 90 days. Food intake, body mass and length were evaluated on a weekly basis. Body composition was assessed through dual-energy X-ray absorptiometry and intra abdominal fat mass was measured at the end of 90 days.

Taro group recorded protein intake (55.5 ± 14.1 vs 43.8 ± 12.8 kcal, P < 0.009), body mass (between 40 and 90 days, P < 0.05), fat mass (147.3 ± 7.7 vs 99 ± 6.1 g, P < 0.001), lean mass (282.8 ± 4 vs 253.5 ± 7 g, P < 0.001), trunk fat mass (97.1 ± 7.7 vs 71.5 ± 4.1 g, P < 0.010), as well as intra-abdominal (31.3 ± 1.9 vs 21.1 ± 1.7 g, P < 0.001), epididymal (9.2 ± 0.8 vs 4.7 ± 0.5 g, P < 0.001) and retroperitoneal (14.2 ± 0.9 vs 8.8 ± 1.2 g, P < 0.002) fat mass higher than that of the Control group.

Taro flour would show anabolic effects on body compartments of rats. The extrapolation of these findings herein recorded for rats to humans requires caution; however, it is necessary conducting further studies to investigate potentials anabolic effects of taro (Colocacia esculenta) flour on the body composition of physical training models.

Brazilian federalism was important in the political game of combating the pandemic for three reasons. First, Brazil's public health system depends heavily on intergovernmental relations between Union, states, and municipalities because there is a policy portfolio based on federative cooperation. Second, the subnational governments' autonomy to act against COVID-19 was constantly questioned by the Federal Government – the conflict between the President and governors was a key piece in all health policy. Finally, states and local governments were primarily responsible for policies to fight against pandemic, but the absence and/or wrong measures taken by the Federal Government (such as the delay in purchasing vaccines) generated intergovernmental incoordination, increased territorial inequality, and reduced the effectiveness of subnational public policies, especially those linked to social isolation. In this context, Brazilian federalism played a dual role in the pandemic. On the one hand, the federative structure partially succeeded in averting an even worse scenario, mitigating the impact of mistaken presidential decisions. The role of subnational governments, especially of the states, was critical as a counterweight to federal decisions. On the other hand, the President actively acted against governors and mayors and, above all, sought to weaken intergovernmental articulations within the Unified Health System (SUS), the federative model designed three decades ago. One could say that the federative actors, such as the Supreme Court (Supremo Tribunal Federal – STF) and subnational governments, were the main obstacles for the Bolsonarist antiscientific agenda. The success of this reaction to President Bolsonaro's negationist populism was partial, but the results of the fight against COVID-19 would have been much worse without these federalist barriers.

Tourism, as a system, develops strategies for risk prevention and mitigation. The shock generated by the COVID-19 pandemic is different when compared with previous events because it is more intense and prone to structural changes. Tourists' perceptions condition their behaviour and decisions, with adverse results on travel and tourism consumption; and hygiene and health risks generate a cause-effect relationship on destination specificities.

From globalisation to risk perception and crisis management, in a framework where technology, communication and digital content represent undeniable importance, we are facing circumstances especially conducive to the redesign of the collective future, where the sustainability of tourism is a collective goal, arising from the right balance between the competitiveness of destinations and climate action.

Given the prospects for the next decade, health and hygiene are structural factors to be considered in decision-making processes. Thus, so the proposed approach contributes to the awareness, by the various stakeholders, of its importance and the need to implement methods and processes compatible with more inclusive and responsible tourism.