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The integral transform method is employed for the hybrid numerical‐analytical solution of the boundary layer formulation in developing turbulent flow inside channels. An algebraic turbulence model due to Cebeci and Smith is adopted, in light of its popularity demonstrated in the recent numerical simulation literature. Numerical results for the velocity components in a parallel‐plates channel are obtained, and the automatic error control feature of the present approach is demonstrated. Critical comparisons with experimental works, as well as with previous simulations that employed differential turbulence models, are also performed.

The purpose of this study is to show the procedure, application and main features of the hybrid numerical-analytical approach known as generalized integral transform technique by using it to study magnetohydrodynamic flow of electrically conductive Newtonian fluids inside flat parallel-plate channels subjected to a uniform and constant external magnetic field.

The mathematical formulation of the analyzed problem is given in terms of a streamfunction, obtained from the Navier–Stokes and energy equations, by considering steady state laminar and incompressible flow and constant physical properties.

Convergence analyses are performed and presented to illustrate the consistency of the integral transformation technique. The results for the velocity and temperature fields are generated and compared with those in the literature as a function of the main governing parameters.

A detailed analysis of the parametric sensibility of the main dimensionless parameters, such as the Reynolds number, Hartmann number, Eckert number, Prandtl number and electrical parameter, for some typical situations is performed.

The purpose of this paper is to provide an analysis of two‐dimensional laminar flow in the entrance region of wavy wall ducts as obtained from the solution of the steady Navier‐Stokes equations for incompressible flow.

The study is undertaken by application of the generalized integral transform technique in the solution of the steady Navier‐Stokes equations for incompressible flow. The streamfunction‐only formulation is adopted, and a general filtering solution that adapts to the irregular contour is proposed to enhance the convergence behavior of the eigenfunction expansion.

A few representative cases are considered more closely in order to report some numerical results illustrating the eigenfunction expansions convergence behavior. The product friction factor‐Reynolds number is also computed and compared against results from discrete methods available in the literature for different Reynolds numbers and amplitudes of the wavy channel.

The proposed methodology is fairly general in the analysis of different channel profiles, though the reported results are limited to the wavy channel configuration. Future work should also extend the analysis to geometries represented in the cylindrical coordinates with longitudinally variable radius.

The error‐controlled converged results provide reliable benchmark results for the validation of numerical results from computational codes that address the solution of the Navier‐Stokes equations in irregular geometries.

Although the hybrid methodology is already known in the literature, the results here presented are original and further challenges application of the integral transform method in the solution of the Navier‐Stokes equations.

This study contributes to the understanding of the health effects of pesticides exposure and of how pesticides have been and should be regulated.

This study presents literature reviews for the period 2000–2013 on (i) the health effects of pesticides and on (ii) preference valuation of health risks related to pesticides, as well as a discussion of the role of benefit-cost analysis applied to pesticide regulatory measures.

This study indicates that the health literature has focused on individuals with direct exposure to pesticides, i.e. farmers, while the literature on preference valuation has focused on those with indirect exposure, i.e. consumers. The discussion highlights the need to clarify the rationale for regulating pesticides, the role of risk perceptions in benefit-cost analysis, and the importance of inter-disciplinary research in this area.

This study relates findings of different disciplines (health, economics, public policy) regarding pesticides, and identifies gaps for future research.

The purpose of this paper is to investigate the mineral content of seven Brazilian infant dairy product categories (petit Suisse cheeses, fermented milks, yogurts, fermented dairy beverage, dairy dessert, Requeijão cremoso spreadable cheese and UHT dairy beverages) and estimate their contribution to daily intake.

The composition of major (Ca, K, Mg, and Na) and trace (Pb, Cd, Cu and Mn) minerals was determined using Inductively Coupled Plasma Optical Emission Spectrometry. Furthermore, a comparative analysis of the mineral levels with the Reference Daily Intake (RDI) at different child development stages was carried out.

High Ca levels were observed in petit Suisse (3.44±1.66 mg g⁻¹), dairy dessert (3.88±0.02 mg g⁻¹) and Requeijão cremoso (4.14±0.07 mg g⁻¹). Dairy dessert presented the highest K level (2.57±0.07 mg g⁻¹), while the Requeijão cremoso presented the highest Na content (4.78±0.10 mg g⁻¹), and both products had the highest Mg contents (238.55±16.27 and 197.39±5.18 µg g⁻¹, respectively). Trace elements (Cd, Cu, Mn and Pb) were below the limit of detection for all commercial dairy foods. Among food products analyzed, petit Suisse cheese and dairy dessert can be considered good sources of calcium, while Requeijão cremoso is high in both calcium and sodium.

This study is the first to analyze the mineral levels of several Brazilian infant dairy foods and the daily intake contribution during important child development stages. These findings provide valuable guidance for researchers and practitioners trying to develop healthy and nutritious dairy products for infants and children.

This chapter aims to analyse how tourism has oscillated from a wicked problem and a geopolitical strategy tool in Brazilian federal tourism public tourism policies (PTP) over the past century (spanning from 1921 to 2022). Recently tourism has garnered significant relevance, emerging as an alternative avenue for development within the constraints and resource limitations faced by the National States. The empirical study collected secondary data from the government official press, encompassing records from the Senate, the House of Representatives, as well as the executive and judiciary branches. Considering this timeframe, a corpus comprising more than 31,000 documents TNAs (‘Tourism Normative Acts’) was meticulously gathered and systematically analysed. Our analytical framework integrates classical geopolitics, with a primary focus on State actors and the nation-building process, and the public policy approach, which is focussed on the degrees of wickedness. Our findings show that (a) the number of international tourists as well as the number of NAT have increased in a considerable way recently, but we cannot directly connect both; (b) three are the periods (1970–1980, 1990–2000, and 2002–2016) in which we can see a tourism geopolitical strategy has been more explicitly and effectively mobilized, and it is not necessarily reflected in the number of NAT, but in the actions generated in each period; and (c) the wicked degree of the tourism policies seem to be reduced according to the more explicit geopolitical strategy is. Despite, the importance tourism has reached, the support system underpinning this endeavour remains deficient, notably in terms of material and financial resources essential for its efficacious execution.

The purpose of this study is to evaluate the effect of the probiotic addition (Lactobacillus paracasei ssp.) on the physicochemical characteristics and antioxidant capacity of white grape juice during refrigerated storage (4°C/28 days). This paper also aims to evaluate the survival of the probiotic culture in the product and under simulated gastrointestinal conditions.

Two formulations of white grape juices were evaluated, one with 2 per cent of probiotic culture addition and the other of pure juice.

The addition of probiotic culture resulted in products with a darker-reddish coloration (L* = 30.6-30.8 and a* = 0.6-0.9) and a lower content of total phenolic compounds (599-697 µg EAG mL⁻¹) (p = 0.05). However, it improved the color stability and maintained the antioxidant activity 1,1-diphenyl-2-picrylhydrazyl (p > 0.05). The viability of the probiotic culture (>10⁹ colony forming unit · 200 mL⁻¹) in the juice was maintained during 21 days of storage, but in simulated gastrointestinal conditions, the functional properties could be guaranteed during the 28 days of refrigerated storage.

The white grape juice is a suitable medium for incorporation of Lactobacillus paracasei.

The survival of the probiotic cultures to the simulated gastrointestinal tract may be significant, even if the product does not have the recommended minimum counts.

The purpose of this study was to evaluate beet and orange mixed juices added with lyophilized Lactobacillus acidophilus probiotic culture.

Two formulations of probiotic beet and orange mixed juices (1:1 e 1:2 v/v) were prepared, stored at 4°C for 28 days and were evaluated for probiotic survival, physicochemical stability, antioxidant activity and sensory acceptance. The probiotic culture was added in a lyophilized form and was not propagated in culture media or juice.

Physicochemical characteristics (pH, titratable acidity, total soluble solids and color) and antioxidant activity showed no undesirable alterations during storage. The number of probiotics followed established minimum requirement for probiotic foods (10⁹ CFU/200mL) during the 28 days of storage. The juices showed good sensory acceptance and purchase intention, especially regarding the color of the product.

The beet and orange mixed juices are suitable carriers for L. acidophilus with a shelf life of at least 28 days at 4°C.

Direct addition of the probiotic culture could result in high probiotic survival in mixed juices, dispensing the propagation step.