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Microneedles are an emerging technology designed to deliver drugs into human tissue. In this work, we assess the microneedle’s manufacturability by employing micromilling with a minimum quantity lubrication (MQL) system. A set of AISI 316L square pyramidal microneedles was fabricated and characterized using dimensional and surface metrology. Needle height (Hn), base length (Lb), tip radius (Rt), and the tip’s angle (θ) were studied. Additionally, surface roughness was quantified to correlate surface topography damage with tool wear (Dr). Experimental data shows tip truncation after manufacturing 30 needles (i.e., a tip radius between ~32 μm and 49 μm for manufacturing 10 and 30 needles, respectively). Additionally, to evaluate the effect of the tip’s morphology on the proficiency of the microneedles for a puncture, a numerical analysis to study the impact of tip truncation length (Tt) on puncture with an in silico assessment using COMSOL Multiphysics was performed. Data and insights from this work suggest that micromilling microneedle arrays is viable, considering the number of needles machined according to the cutting parameters selected to ensure functionality.

El objetivo de este trabajo es presentar una propuesta de Modelo de Arquitectura Cognitiva Artificial SOAR basada en el proceso de visión, reconocimiento de patrones y toma de decisiones que realiza el ser humano. El entorno debe garantizar ciertas condiciones previas para su correcto funcionamiento. Nuestro prototipo de sistema de arquitectura artificial cognitiva está bioinspirado en la forma en que los humanos trabajan para determinar si una persona es conocida o no.

The understanding of dimensional variations produced by laser powder bed fusion is critical in components with small features and with dimensions close to the inherent limits of the process. In this context, two reference geometries were used: (a) straight walls to quantify dimensional relative error for small features and (b) a latticed neck region of a fatigued specimen (cubic and hexagonal cell design, with design strut sizes of 250 µm, 500 µm, and 1000 µm in cell size). Samples were fabricated out of AISI 316L stainless steel powder with different building orientations. The metrology techniques used were the following: focus variation microscopy, optical microscopy and micro-computed tomography. The straight wall characterization shows that built orientation does not influence dimensional relative error for walls with less than 750 µm. Acceptable dimensional relative errors (~ 2% to ~ 15%) are achieved only in walls with 750 µm in width of more. For lattice structures, the fine struts (250 µm) show a significant level of dimensional relative error (~ 5% to ~ 25%). This additive manufacturing process delivers more consistent dimensions for coarse struts (500 µm), with relative errors between ~ 2% and ~ 4%. All metrology techniques showed the same trends in terms of capturing the dimensional variations for fine and coarse struts.

O objetivo deste estudo foi desenvolver e analisar a validade de conteúdo, constructo e a fidedignidade de um questionário para avaliar a demanda física e operacional, saúde e condições de trabalho em policiais e bombeiros militares. O Questionário de Saúde e Performance para Militares (QSPM) foi desenvolvido por pesquisadores militares e não militares, a validade foi analisada com o índice de validade de conteúdo (IVC), análise fatorial exploratória e a fidedignidade com o percentual de concordância (%C), coeficiente Kappa e alfa de Cronbach. Nove juízes participaram da validação de conteúdo, 732 militares (15% mulheres) participaram da etapa de validação de constructo e 262 militares (18% mulheres) responderam duas vezes ao QSPM para a verificação da fidedignidade. As análises foram realizadas no software SPSS 26 e o nível de significância mantido em 5%. O QSPM apresentou o IVC de 0,98 e variância total explicada em 54,7%. A reprodutibilidade apresentou valores de %C entre 97,2 - 100,0%, Kappa entre 0,94 - 1,00 (p < 0,05) e alpha de Cronbach entre 0,80 - 1,00 (p < 0,05). Conclui-se que o QSPM apresentou validade de conteúdo, constructo e fidedignidade para avaliar a frequência da demanda física e operacional, as condições de saúde e de trabalho de policiais e bombeiros militares.

A novel manufacturing approach was used to fabricate metallic scaffolds. A calibration of the laser cutting process was performed using the kerf width compensation in the calculations of the tool trajectory. Welding defects were studied through X-ray microtomography. Penetration depth and width resulted in relative errors of 9.4%, 1.0%, respectively. Microhardness was also measured, and the microstructure was studied in the base material. The microhardness values obtained were 400 HV, 237 HV, and 215 HV for the base material, HAZ, and fusion zone, respectively. No significant difference was found between the microhardness measurement along with different height positions of the scaffold. The scaffolds’ dimensions and porosity were measured, their internal architecture was observed with micro-computed tomography. The results indicated that geometries with dimensions under 500 µm with different shapes resulted in relative errors of ~2.7%. The fabricated scaffolds presented an average compressive modulus ~13.15 GPa, which is close to cortical bone properties. The proposed methodology showed a promising future in bone tissue engineering applications.

Environmental protection is a continuous challenge that requires innovating the combustion process of boilers that emit polluting gases. This research proposes a novel pyroacuotubular (mixed) boiler design that reduces the emission of combustion gases by hot water and steam. The applied methodology considers the dimensioning-construction, modification, and analytical calculation of water volume, metallic masses, heat for hot water and steam generation, and combustion gases. The Ganapaty method of heat transfer is applied to prioritize the velocity of gas displacement, the pressure drop along the pipe, and its application on surfaces. In the parallel generation of hot water and steam, a mass of CO2 (1782.72 kg/h) and CO (5.48 kg/h) was obtained; these masses were compared with the results of the proposed design, obtaining a reduction in the mass of gases emitted to the environment in hot water CO2 (44.35%) and CO (44.27%); steam CO2 (55.65%) and CO (55.66%). A significant reduction was achieved in the simultaneous generation of hot water and steam compared to the individual generation, which shows that the simultaneous generation of the pyroacuotubular (mixed) boiler reduces the emission of combustion gases.

BACKGROUND: Many factors may negatively impact physical activity (PA), but studies lack evidence of individual predictors of perceived barriers to PA among adults in primary healthcare units. OBJECTIVE: To analyze associations between sociodemographic characteristics, health conditions, leisure-time physical activity (LTPA), PA counseling and perceived barriers to LTPA among adult patients in primary healthcare units of the National Health System in Brazil. DESIGN AND SETTING: Cross-sectional study on a representative sample of adults in primary healthcare units in São José dos Pinhais, Paraná, Brazil. METHODS: This study was conducted in 2019, among 779 adults (70% women). Barriers to LTPA, sociodemographic characteristics (sex, age, marital status, skin color, education and income), health conditions (body mass index, hypertension, diabetes, dyslipidemia, coronary disease and medications), LTPA level and PA counseling received were measured using validated, standardized procedures. The data were analyzed using chi-square and Mann-Whitney U tests. RESULTS: The most prevalent barriers were “feeling too tired” (53%) and “lack of time” (52%). PA counseling was inversely associated with “lack of time” (45% versus 57%; P < 0.001) but positively associated with “injury or disease” (38% versus 29%; P = 0.008). There was an inverse linear trend between the number of barriers and LTPA (walking and total) (P < 0.001). Most barriers differed in comparisons of sociodemographic characteristics, health conditions, LTPA and counseling (P < 0.05). CONCLUSIONS: The barriers vary according to the individual predictors. Counseling strategies need to be specific for each barrier and may be promising for promoting LTPA within primary healthcare.

Counseling by health professionals has promising results in behavior change and is recommended as part of integrated community interventions. However, the knowledge about sedentary behavior (SB) counseling is incipient. The study aimed to identify the prevalence and explore the associated factors with SB counseling received from healthcare professionals by adults in primary health care (PHC) in Brazil. A cross-sectional study was conducted in 2019 that included a representative sample of 779 users in all 15 basic health units (BHU) in São José dos Pinhais, Paraná. We identified those who reported having received SB counseling during a consultation. The association between the sociodemographic factors, chronic diseases, access to health services, physical activity, SB, and counseling were analyzed using Poisson regression in a hierarchical model. The prevalence of counseling was 12.2% (95% CI: 10.1–14.7%); it was higher in women (PR: 1.77; 95% CI: 1.10–2.83), those aged ≥60 yrs (PR: 1.84; 95% CI: 1.14–2.98), BMI ≥ 30 kg/m2 (PR: 2.60; 95% CI: 1.31–5.17), who consume ≥3 medications (PR: 2.21; 95% CI: 1.06–4.59), and those who spend a prolonged period of the day engaged in SB (4th quartile PR: 3.44; 95% CI: 1.88–6.31). The results highlight that SB counseling is underutilized and incipient in PHC. Understanding these results can help managers and healthcare professionals in BHU teams to implement and direct specific actions to reduce SB in adults through counseling.

In this article, a recent formulation for real-time simulation is developed combining the strain energy density of the Spring Mass Model (SMM) with the equivalent representation of the Strain Energy Density Function (SEDF). The resulting Equivalent Energy Spring Model (EESM) is expected to provide information in real-time about the mechanical response of soft tissue when subjected to uniaxial deformations. The proposed model represents a variation of the SMM and can be used to predict the mechanical behavior of biological tissues not only during loading but also during unloading deformation states. To assess the accuracy achieved by the EESM, experimental data was collected from liver porcine samples via uniaxial loading and unloading tensile tests. Validation of the model through numerical predictions achieved a refresh rate of 31 fps (31.49 ms of computation time for each frame), achieving a coefficient of determination R2 from 93.23% to 99.94% when compared to experimental data. The proposed hybrid formulation to characterize soft tissue mechanical behavior is fast enough for real-time simulation and captures the soft material nonlinear virgin and stress-softened effects with high accuracy.

The growth of additive manufacturing processes has enabled the production of complex and smart structures. These fabrication techniques have led research efforts to focus on the application of cellular materials, which are known for their thermal and mechanical benefits. Herein, we studied the mechanical behavior of stainless-steel (AISI 316L) lattice structures both experimentally and computationally. The lattice architectures were body-centered cubic, hexagonal vertex centroid, and tetrahedron in two cell sizes and at two different rotation angles. A preliminary computational study assessed the deformation behavior of porous cylindrical samples under compression. After the simulation results, selected samples were manufactured via laser powder bed fusion. The results showed the effects of the pore architecture, unit cell size, and orientation on the reduction in the mechanical properties. The relative densities between 23% and 69% showed a decrease in the bulk material stiffness up to 93%. Furthermore, the different rotation angles resulted in a similar porosity level but different stiffnesses. The simulation analysis and experimental results indicate that the variation in the strut position with respect to the force affected the deformation mechanism. The tetrahedron unit cell showed the smallest variation in the elastic modulus and off-axis displacements due to the cell orientation. This study collected computational and experimental data for tuning the mechanical properties of lattice structures by changing the geometry, size, and orientation of the unit cell.

Objective Summarize the effects of interventions designed to promote physical activity during elementary school recess in children between 5 and 10 years old. Effective school interventions for children can promote physical activity and healthy behaviors. Methods PubMed, Scopus, Bireme, SciELO, Web of Science, PsychINFO, Proquest, Physical Education Index, Sports Discus, and Eric databases were included in the data search. Original intervention articles on physical activity that used regression methods, published between 2000 and 2019 in English, Portuguese and Spanish were analyzed. Analyses were performed in 2019. Outcomes were organized according to the direction of the association by independent variables. Ten articles were considered eligible for data extraction and evaluation. Results Several strategies were used including playground markings, demarcation of physical activities zones, group activities, availability of sports equipment and facilities. Most of the studies were conducted in the United States. Recess periods ranged from 20–94 min per day and intervention time ranged from 6 weeks to 2 years. Recess duration and intervention effects were positively associated with physical activity. Gender (girls) and age (oldest) were negatively associated with physical activity during recess. Conclusions Interventions based on modifications of school environment such as playground markings demarcation of physical activities zones, group activities, availability of sports equipment and facilities are cheap and cost-effective for increasing physical activity in school recess.

Human skin is characterized by rough, elastic, and uneven features that are difficult to recreate using conventional manufacturing technologies and rigid materials. The use of soft materials is a promising alternative to produce devices that mimic the tactile capabilities of biological tissues. Although previous studies have revealed the potential of fillers to modify the properties of composite materials, there is still a gap in modeling the conductivity and mechanical properties of these types of materials. While traditional Finite Element approximations can be used, these methodologies tend to be highly demanding of time and processing power. Instead of this approach, a data-driven learning-based approximation strategy can be used to generate prediction models via neural networks. This paper explores the fabrication of flexible nanocomposites using polydimethylsiloxane (PDMS) with different single-walled carbon nanotubes (SWCNTs) loadings (0.5, 1, and 1.5 wt.%). Simple Recurrent Neural Networks (SRNN), Long Short-Term Memory (LSTM), and Gated Recurrent Units (GRU) models were formulated, trained, and tested to obtain the predictive sequence data of out-of-plane quasistatic mechanical tests. Finally, the model learned is applied to a dynamic system using the Kelvin-Voight model and the phenomenon known as the bouncing ball. The best predictive results were achieved using a nonlinear activation function in the SRNN model implementing two units and 4000 epochs. These results suggest the feasibility of a hybrid approach of analogy-based learning and data-driven learning for the design and computational analysis of soft and stretchable nanocomposite materials.