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Study question Are there ageing-related alterations in human sperm protein and small RNA content that can be responsible for the age-associated decline in male fertility? Summary answer Our results revealed a set of proteins and small RNAs, particularly miRNAs, that are altered in older men. What is known already Male infertility is a common health problem strongly influenced by lifestyle and environment. Advanced paternal age, in particular, has been largely associated with alterations in testicular structure and function, impaired semen parameters and DNA integrity, lower pregnancy rates and decline in offspring fitness. The decline in sperm quality with age was also associated with an increase in oxidative stress. However, only a few studies reported the deregulation of specific sperm proteins or RNAs associated with this risk factor for male infertility. Study design, size, duration A hundred and twenty Portuguese men from the Aveiro region were recruited between January 2019 and December 2020 at Hospital Infante D. Pedro E.P.E. (Aveiro, Portugal). All donors provided semen samples for in vitro studies with human spermatozoa. Samples were divided into four groups according to men’s age: (G1) less than 30 years; (G2) between 30 and 35 years; (G3) between 35 and 40 years and (G4) more than 40 years. Participants/materials, setting, methods One hundred twenty human sperm samples from volunteer donors were included in this study. Basic semen analyses were performed according to WHO’s guidelines. To avoid the possible contamination by somatic cells, density gradient sperm selection was performed. Nineteen normozoospermic human sperm samples were divided into four groups according to their age and their proteome was evaluated by quantitative proteomic analysis. The small RNA content of sixteen human sperm samples was investigated using small RNA sequencing. Main results and the role of chance In this study 120 men aged between 19- and 56-years old (mean age 35.2 ± 6.32 years) were recruited. Our data showed no correlation between paternal age and any seminal parameter investigated, contrary to what was previously described in other study populations. Proteomic analyses revealed 46 differentially expressed proteins (DEPs) between the four study groups (p-value< 0.05;|log2FC|=1.5). In particular, lysosomal protein LAMP1 was significantly upregulated in sperm from men younger than 30 years old compared with men with more than 35 years old. In men younger than 35 years old, cytochrome c oxidase subunit 3 (MT-CO3) and DnaJ homolog subfamily A member 1 (DNAJA1) were consistently downregulated in relation to sperm from men aged between 35 and 40 years old. Gene ontology analysis of all the deregulated sperm proteins shown that response to unfolded protein, positive regulation of mitochondrion organization, negative regulation of phosphoprotein phosphatase activity, positive regulation of apoptotic process, and spermatogenesis are common biological processes affected. Transcriptomic analysis identified 5 differentially expressed miRNAs (DEMs) between the four groups studied (p-value< 0.05), among which has-miR-374c-3p and miR-103a-3p were significantly upregulated in men younger than 35 years old compared to sperm from men aged between 35 and 40 years old. Limitations, reasons for caution The major limitations of this study are the relatively small sample size and the limited number of participants younger than 20 years and older than 45 years. Additionally, we cannot exclude the influence of unmeasured confounders, including lifestyle factors such as alcohol consumption, diet, exercise, and stress, in our findings. Wider implications of the findings Despite reproductive history and basic semen analysis being the primary steps in the assessment of male infertility, this routine examination is insufficient to explain almost 30% of the cases. The DEPs and DEMs identified could help to elucidate and/or became potential diagnostic markers for age-associated decline in human sperm quality. Trial registration number not applicable

This chapter is devoted to study heat and mass transfer and dimension variations of arbitrary-shaped porous materials. The focus is on the drying process of clay ceramic materials. Here, different topics related to history, manufacturing, drying process, phenomenological lumped modeling, and parameters estimation are present and discussed. Emphasis is given to industrial clay bricks, with theoretical and experimental approaches.

Resin transfer molding (RTM) is one technique that has been used to produce polymer composites, which consists in injecting a thermoset pre-catalysed resin into a closed mold containing a dry fiber preform. In this sense, this study aims to investigate the effect of the calcium carbonate content (CaCO3) in the polyester resin during the RTM process. Several experiments were conducted using glass fiber mat molded in a RTM system with cavity dimensions 320 x 150 x 3.6 mm, at room temperature, and different injection pressure (0.75 bar) and CaCO3content (0, 10, 20, 30 and 40%). Results of the physical parameters such as viscosity, permeability, and mobility, and flow front position of the resin into the mold along the RTM process are presented and analyzed. From the results was concluded that the higher the injection pressure and lower CaCO3content into the resin, the lower filling time.

This work aims to realize an experimental investigation of the drying of castor bean fruits (Ricinus communis L., “BRS Energia” variety) in oven. Results of the average moisture content and surface temperature of the product as a function of time were analyzed for different drying air temperatures (40, 50, 60, 70, 80, 90 and 100°C). Results shows that increasing drying temperature and decreasing air relative humidity we have an increases in the drying rate and more quickly the castor fruits reaches both thermal and hygroscopic equilibrium. It was found that high drying rates generates hydric and thermal stresses inside the product, causing cracks and deformations in the castor bean fruits.

Rice (Oryza sativa L.) is a greatly important socio-economic crop. Immediate threshing and drying of wet harvested grains, to reach 18–19% (w.b) moisture content, is a practical method used by individual farmers to slow deterioration and increase selling prices. However, rough rice grain is different from other grains because it has an outer cover shell (palea and lemma) and a bran layer. Thus, the heat and mass transfer processes that take place during grain drying are different from those of other cereal grains, so understanding the effect of different treatments, drying temperature, moisture content and the gradients in rice grains is essential to optimize the drying conditions. In this sense, the current study aims to analyze the moisture removal and its effects on the stress cracking and the number of brown rice grains (BRSMG CONAI variety) at the temperatures of 60 and 80°C.

This work aims to conduct an experimental study of the drying kinetics of castor bean fruits (Ricinuscommunis L., “BRS Energia” variety). Experiments were conducted using an oven at air temperatures 50 and 70°C and air relative humidity values 16.34 and 6.24%, respectively. The castor bean fruits were considered as a triaxial spheroid. The experimental moisture content data as a function of time were fitted to different lumped models (namely Henderson and Pabis, Page, Midilli and two-term exponential models) available in the literature.The values of the effective moisture diffusivity were obtained from the Fick's diffusion model. Results shows that the two-term drying model could adequately describe the thin layer drying behavior of castor bean fruit, and that the effective moisture diffusivity increases with increasing drying air temperature.

Simulate the rice drying process at specific drying conditions is of great interest to optimize the process and ensure a better quality of the final product. In the present work, experimental drying procedures of rough rice grains (BRSMG CONAI variety) was reported and drying kinetic was obtained at temperature using 40°C. The results were compared with simulated data by means of the liquid diffusion model equilibrium boundary condition. The geometry used to represent the rice grain was prolate spheroid. For this purpose, the diffusion equation, written in cylindrical coordinates, and solved via Galerkin-based integral method considering the constant diffusion coefficient. A good agreement was observed between predicted and experimental data. It was also possible to observe that the highest moisture gradients occur at the tip of the grain, which is region more affected by thermal and hydric stresses. The studied model can be used to solve problems involving diffusion processes, such as: drying, wetting, heating and cooling, provided that the geometrical shape of the body is similar to prolate spheroid.

O ensino da matemática na educação fundamental é um desafio para docentes e pesquisadores. Para superar essas barreiras técnicas metodológicas o lúdico tem sido utilizado. O lúdico está associado a dança, a música e ao jogar, consiste em um mecanismo poderoso para aumentar o interesse dos alunos por alguma disciplina ou conteúdo. Essa metodologia torna o aprendizado mais divertido e interessante, possibilitando o ensino do conteúdo de uma maneira leve. Devido a sua importância, este trabalho tem como objetivo utilizar o lúdico como ferramenta no auxílio do ensino de frações. A pesquisa foi realizada em uma Escola Municipal, com 30 alunos da turma do 6º ano, sendo 13 do sexo masculino e 17 do sexo feminino. Foi feito uma análise da temática, através de um questionário, a aplicação do jogo e uma avaliação no final das atividades. Verificou-se que, com a inserção dos jogos nas aulas, elas se tornaram mais dinâmica e prazerosa, promovendo uma maior interação entre os alunos/material-manipulável/professor, que contribuiu para uma melhora na aprendizagem do conteúdo de frações.

This paper aims to present an experimental study of rough rice (BRSMG CONAI cultivar) drying by using a stationary method. The grain was dried in an oven with air mechanical movement under controlled conditions of velocity, temperature and relative humidity. In order to obtain balanced moisture content, the samples studied were kept at 40 and 70°C. Results of the drying and heating kinetics of the grain during the process are shown and analyzed. It was found that higher drying rate and lower time for drying as higher air temperature (70°C) is used. It can be concluded that the reduction of the moisture content of the grain, is considered very complex and, depending on the method and drying conditions, can substantially provokes breaking and cracks, which reduces final product quality.

This work aims to study convective drying of ellipsoidal solids. Aplication has been done to drying of wheat Kernel. Diffusion equation in cylindrical coordinates has been solved via Galerkin-based integral method considering convective boundary conditions and constant thermo-physical properties. Results of the temperature and moisture content are presented and compared with wheat experimental drying data at relative humidity 33.8 % and temperature 47.0°C. It was verified that heat transfer in the drying process occurs much faster than the mass transfer, thus providing a rapid heating of the product, which reduces grain quality.

Transport phenomena in porous media represent an important research area related to heat and mass transfer, and fluid flow fields. This chapter presents information about anomalous behaviour of moisture transient diffusion in vegetable fiber-reinforced composites materials. Composites reinforced with natural fibers are sensitive to influences from environmental agents such as moisture and temperature. Herein, topics related to theory, experiments, mathematical modeling and solution procedures, and technological applications are presented and discussed in detail. An advanced model that (Langmuir-type model) to describe water absorption in polymer composites and the analytical (Laplace transform technique) and numerical (finite-volume method) solutions of the governing equation has been obtained, considering constant thermo-physical properties. In the Langmuir model, moisture sorption can be explained by assuming that water exists in the free and bound phases inside the material. Application has been done to water uptake in Caroa fiber-reinforced polymer composites. Results of the absorption kinetics and concentration distribution of water (free and trapped water molecules) within the material along the process are presented and analyzed. Predicted results compared to experimental data of average moisture content have shown that the model was effective for description of the phenomenon, allowing a better understanding about the effects of moisture migration mechanisms.

The objective of this study was to investigate numerically heat and mass transport during drying of grains with particular reference to bean and rough rice. The proposed mathematical models based on the Fick’s and Fourier’s Laws consider constant physical properties and convective boundary condition at the surface of the solid. The solutions of the governing equations were performed using ANSYS CFX®software. The grains were regarded as an ellipsoid of revolution. Results of the drying and heating kinetics and moisture content and temperature distributions in the grains along the drying process are presented and analyzed.

Drying can be defined as a simultaneous heat and mass transfer process between product and air drying. These phenomena have occurred due to thermal and moisture gradients and they are affected by different parameters. The inadequate management of this process can cause severe damage to the product such as cracking, loss of nutritional properties and even loss of the product quality. Thus, this paper proposes a numerical study of heat and mass transfer that occurs during the rough rice drying process, using the commercial software ANSYS CFX®. Herein the grain was considered as ellipsoid of revolution.