The production and materials of mouthguards: Conventional vs additive manufacturing - A systematic review.

This investigation presents a critical analysis of mouthguard production, focusing on the evaluation of conventional vs additive manufacturing methods, the materials involved, and aspects such as their failure and prevention. It also summarizes the current trends, perspectives, and the main limitations. It is shown that some of the shortcomings can be solved by implementing additive manufacturing technologies, which are systematically reviewed in this research. Due to the specific materials used to produce mouthguards, there are certain additive manufacturing technologies that dominate and a wide variety of raw materials. The costs vary depending on the technology.

Reliability of dynamic and isometric upper muscle strength testing in breast cancer survivors.

Breast cancer is the most common cancer in women worldwide, and its treatment usually involves a combination of many medical procedures, including surgery, chemotherapy, radiotherapy, and hormonal therapy. One of the detrimental effects on physical function is reduced upper limb muscle strength. This study aimed to evaluate upper body strength intra-day and inter-day (test-retest) reliability using the handgrip strength test (HGS) and the bilateral isometric bench press (BIBP) and the test-retest reliability of the one repetition maximum on the bench press (BP-1RM) in breast cancer survivors (BCS). Thirty-two (52.94 ± 8.99 yrs) BCS participated in this study. The muscle strength tests were performed in two different moments, three to seven days apart. Intraclass coefficient correlation (ICC) and coefficient of variation (CV) were used to assess the reliability. Standard error of measurement (SEM), typical error of measurement (TEM), and minimally detectable change (MDC) analyses were performed. The Bland-Altman analysis was used to assess the agreement between test-retest. We found a reliability that can be described as "high" to "very high" (ICC ≥ 0.88; CV ≤ 10%) for intra-day and test-retest. SEM% and MDC% were lower than 5% and 11%, respectively, for all intra-day testing. SEM% and TEM% ranged from 3% to 11%, and MDC% ranged from 9% to 23% in the test-retest reliability. The agreement demonstrated a systematic bias ranging from 2.3% to 6.0% for all testing, and a lower systematic bias may be presented in the non-treated side assessed by HGS and BIBP. HGS, BIBP, and BP-1RM assessments are reliable for measuring upper-body muscle strength in BCS.

Effect of warm-up protocols using lower and higher loads on multiple-set back squat volume-load.

Background: The present study aimed to investigate the effects of post-activation performance enhancement (PAPE) after three warm-up protocols on back squat performance in trained men. Methods: Fourteen resistance-trained men performed conditioning activity (CA) with high-load (HL-CA), low-load (LL-CA), or usual specific warm-up as a control (CON). HL-CA consisted of one set of three repetitions with 90% of one repetition maximum (RM); LL-CA consisted of one set of six repetitions with 45% of 1 RM performed at maximal velocity; CON involved eight repetitions with 45% of 1 RM at controlled velocity. The participant's performance was measured using the total number of repetitions and volume load (reps × load × sets). Results: There were no significant differences between warm-up for the total number of repetitions (p = 0.17) or total volume load (p = 0.15). There was no difference between conditions for the number of repetitions (main condition effect; p = 0.17); however, participants achieved a significantly higher volume load after HL-PAPE than after CON for the first set (p = 0.04). Conclusion: High or low equated-load CA used as warm-up strategies did not potentiate subsequent performance enhancement in multiple-set back squat exercise performed until muscle failure in comparison with usual warm-up.

Green synthesis of silver nanoparticle using pollen extract from Tetragonisca angustula a stingless bee.

This study explores the green synthesis of silver nanoparticles (AgNPs) using a methanolic extract of fermented pollen from Tetragonisca angustula, a species of stingless bees. The AgNPs exhibit spherical morphology, low charge values, and suspension stability, with their unique composition attributed to elements from the pollen extract. Antioxidant assays show comparable activity between the pollen extract and AgNPs, emphasizing the retention of antioxidant effects. The synthesized AgNPs demonstrate antimicrobial activity against multidrug-resistant bacteria, highlighting their potential in combating bacterial resistance. The AgNPs exhibit no toxic effects on Drosophila melanogaster and even enhance the hatching rate of eggs. The study underscores the innovative use of stingless bee pollen extract in green synthesis, offering insights into the varied applications of AgNPs in biomedicine.

Gouy phase and quantum interference with cross-Wigner functions for matter-waves.

The Gouy phase is essential for accurately describing various wave phenomena, ranging from classical electromagnetic waves to matter waves and quantum optics. In this work, we employ phase-space methods based on the cross-Wigner transformation to analyze spatial and temporal interference in the evolution of matter waves characterized initially by a correlated Gaussian wave packet. First, we consider the cross-Wigner of the initial wave function with its free evolution, and second for the evolution through a double-slit arrangement. Different from the wave function which acquires a global Gouy phase, we find that the cross-Wigner acquires a Gouy phase difference due to different evolution times. The results suggest that temporal like-Gouy phase difference is important for an accurate description of temporal interference. Furthermore, we propose a technique based on the Wigner function to reconstruct the cross-Wigner from the spatial intensity interference term in a double-slit experiment with matter waves.

Alkaline Activation of Binders: A Comparative Study.

Binders formulated with activated alkali materials to replace Portland cement, which has high polluting potential due to CO2 emissions in its manufacture, have increasingly been developed. The objective of this study is to evaluate the main properties of activated alkali materials (AAM) produced by blast furnace slag, fly ash, and metakaolin. Initially, binders were characterized by their chemical, mineralogical and granulometric composition. Later, specimens were produced, with molarity variation between 4.00 and 5.50, using the binders involved in the research. In preparing the activating solution, sodium hydroxide and silicate were used. The evaluated properties of AAM were consistency, viscosity, water absorption, density, compressive strength (7 days of cure), calorimetry, mineralogical analysis by X-ray diffraction, and morphological analysis by scanning electron microscopy. The results of evaluation in the fresh state demonstrate that metakaolin has the lowest workability indices of the studied AAM. The results observed in the hardened state indicate that the metakaolin activation process is optimized with normal cure and molarity of 4.0 and 4.5 mol/L, obtaining compressive strength results after 7 days of curing of approximately 30 MPa. The fly ash activation process is the least intense among the evaluated binders. This can be seen from the absence of phases formed in the XRD in the compositions containing fly ash as binder. Unlike blast furnace slag and metakaolin, the formation of sodalite, faujasite or tobermorite is not observed. Finally, the blast furnace slag displays more intense reactivity during thermal curing, obtaining compressive strength results after 7 days of curing of around 25 MPa. This is because the material's reaction kinetics are low but can be increased in an alkaline environment, and by the effect of temperature. From these results, it is concluded that each precursor has its own activation mechanism, observed by the techniques used in this research. From the results obtained in this study, it is expected that the alkaline activation process of the types of binders evaluated herein will become a viable alternative for replacing Portland cement, thus contributing to cement technology and other cementitious materials.

Susceptibility of solid organ transplant recipients to viral pathogens with zoonotic potential: A mini-review.

A substantial number of zoonotic diseases are caused by viral pathogens, representing a significant menace to public health, particularly to susceptible populations, such as pregnant women, the elderly, and immunocompromised individuals. Individuals who have undergone solid organ transplantation frequently experience immunosuppression, to prevent organ rejection, and, thus are more prone to opportunistic infections. Furthermore, the reactivation of dormant viruses can threaten transplant recipients and organ viability. This mini-review examines the up-to-date literature covering potential zoonotic and organ rejection-relevant viruses in solid organ transplant recipients. A comprehensive list of viruses with zoonotic potential is highlighted and the most important clinical outcomes in patients undergoing transplantation are described. Moreover, this mini-review calls attention to complex multifactorial events predisposing viral coinfections and the need for continuous health surveillance and research to understand better viral pathogens' transmission and pathophysiology dynamics in transplanted individuals.

Organic contamination and multi-biomarker assessment in watersheds of the southern Brazil: an integrated approach using fish from the Astyanax genus.

We aimed to examine the responses of pollution biomarkers in feral fish from Astyanax genus collected at three hydrographic regions in southern Brazil and the capacity of these tools to differentiate between various levels of contamination. To achieve this, levels of organochlorine pesticides (liver), as well as the biomarkers AChE (muscle and brain), TBARS (liver), and EROD (liver) were assessed. Collections were conducted in four municipalities (Alegrete, Caraá, Lavras, and Santa Vitória) during 1 year, encompassing winter and summer. Fish from Alegrete were the most contaminated overall, but animals sampled in Caraá, and Lavras also displayed elevated levels of current-use pesticides. Elevated levels of endosulfans, DDTs, HCHs, and current-use pesticides were accompanied by elevated levels of TBARS in the liver. Conversely, fish from Santa Vitória exhibited the highest levels of PAHs, accompanied by elevated levels of EROD in the liver and reduced levels of AChE in muscle and brain. TBARS proved to be a reliable biomarker for assessing impacts arising from pesticide accumulation, while EROD and AChE served as valuable indicators of impacts resulting from PAHs accumulation. Ultimately, the results obtained in this study demonstrate the reliable use of the proposed biomarkers for tracking biological impacts stemming from aquatic pollution using feral Astyanax as biomonitoring species.

Effects of chemotherapy treatment on muscle strength indicators, functional capacity and biopsychosocial aspects of women with breast cancer.

Evidences on the effects of chemotherapy treatment cycles on measures of muscle, mental state, social and cognitive performance are scarce. The objective of this study was to analyze the effects of chemotherapy cycles on muscle strength and activation, functional capacity, quality of life, fatigue and anxiety of women with breast cancer. Therefore, twenty-two women divided into a treatment group (n = 10; 46.6 ± 9.6 years) and control group (n = 12; 51.6 ± 7.0 years) participated in the study. Analysis of muscle performance, quality of life, fatigue and anxiety after the 2nd and 4th cycle of chemotherapy with anthracyclines were performed in women with breast cancer (TRA) and compared to healthy women (CTR). Two-way ANOVA was used to compare the variance of the means and the significance level was set as P≤0.05. The results showed Differences in the muscular activation of the vastus mediallis between the groups at post time (P = 0.038), as well as in the sit and stand test in the baseline (P<0.001) and post moment (P<0.001). Functional capacity performance was different between baseline (P<0.001) and post-time (P<0.001) groups. Additionally, the TRA group worsened the quality of life in the domains of functional capacity (P<0.001) and limitation of physical aspects (P = 0.002), besides presenting negative changes in fatigue. Thus, anthracycline chemotherapy cycles reduce muscular performance and affect biopsychosocial variables in women with breast cancer.

Chronic exposure to 2,2'-azobis-2-amidinopropane that induces intestinal damage and oxidative stress in larvae of Drosophila melanogaster.

Embryonic development is exceptionally susceptible to pathogenic, chemistry and mechanical stressors as they can disrupt homeostasis, causing damage and impacted viability. Oxidative stress has the capacity to induce alterations and reshape the environment. However, the specific impacts of these oxidative stress-induced damages in the gastrointestinal tract of Drosophila melanogaster larvae have been minimally explored. This study used 2,2-azobis (2-amidinopropane) dihydrochloride (AAPH), a free radical generator, to investigate oxidative stress effects on Drosophila embryo development. The results showed that exposing Drosophila eggs to 30 mM AAPH during 1st instar larva, 2nd instar larva and 3rd instar larva stages significantly reduced hatching rates and pupal generation. It increased the activity of antioxidant enzymes and increased oxidative damage to proteins and MDA content, indicating severe oxidative stress. Morphological changes in 3rd individuals included decreased brush borders in enterocytes and reduced lipid vacuoles in trophocytes, essential fat bodies for insect metabolism. Immunostaining revealed elevated cleaved caspase 3, an apoptosis marker. This evidence validates the impact of oxidative stress toxicity and cell apoptosis following exposure, offering insights into comprehending the chemically induced effects of oxidative stress by AAPH on animal development.

Replacing concurrent controls with virtual control groups in rat toxicity studies.

Virtual control groups (VCGs) in nonclinical toxicity represent the concept of using appropriate historical control data for replacing concurrent control group animals. Historical control data collected from standardized studies can serve as base for constructing VCGs and legacy study reports can be used as a benchmark to evaluate the VCG performance. Replacing concurrent controls of legacy studies with VCGs should ideally reproduce the results of these studies. Based on three four-week rat oral toxicity legacy studies with varying degrees of toxicity findings we developed a concept to evaluate VCG performance on different levels: the ability of VCGs to (i) reproduce statistically significant deviations from the concurrent control, (ii) reproduce test substance-related effects, and (iii) reproduce the conclusion of the toxicity study in terms of threshold dose, target organs, toxicological biomarkers (clinical pathology) and reversibility. Although VCGs have shown a low to moderate ability to reproduce statistical results, the general study conclusions remained unchanged. Our results provide a first indication that carefully selected historical control data can be used to replace concurrent control without impairing the general study conclusion. Additionally, the developed procedures and workflows lay the foundation for the future validation of virtual controls for a use in regulatory toxicology.

Rice Husk with PLA: 3D Filament Making and Additive Manufacturing of Samples for Potential Structural Applications.

Additive manufacturing has garnered significant attention as a versatile method for fabricating green and complex composite materials. This study delves into the fabrication of polymer composites by employing polylactic acid (PLA) in conjunction with rice husk as a reinforcing filler. The filaments were made by an extruded filament maker and then were used to make tensile and impact samples by another extrusion technology, fused deposition modeling (FDM). The structural and morphological characteristics of the composite materials were analyzed using scanning electron microscopy SEM. Results show that both the filament and samples are very reliable in producing polymer parts with this rice husk solid waste. This research contributes to increasing materials' circularity and potentially creating a local social economy around rice production, where this waste is not much used.

Coping with Gender Dysphoria in a Rural Environment during Adolescence.

Gender dysphoria is socially more visible and discussed today, but still underdiagnosed. It refers to distress and/or impaired function caused by inconsistency between the sex assigned at birth and gender identification. Clinical manifestations are variable. Lack of training and investment in gender issues make the diagnosis and management in primary care complex, particularly in conservative and isolated communities, with poor access to information and specialized health services. We describe the diagnosis of gender dysphoria and use of a patient centered multidisciplinary and family approach in a 12-year-old rural born adolescent, assigned female at birth. Our aim is to raise awareness of early symptoms and signs of gender dysphoria and problems faced by transgender people and their families during childhood, leading to gender dysphoria, and we hope our successful approach might improve healthcare provision for these patients, particularly in rural areas.

Antioxidant and anti-Alzheimer's potential of Tetragonisca angustula (Jataí) stingless bee pollen.

Alzheimer's disease (AD) is considered the leading cause of dementia in the elderly worldwide. It results in progressive memory loss and impairment of cognitive and motor skills, leading to a high degree of disability and dependence. The development of AD is associated with the accumulation of senile plaques in the brain, caused by the amyloidogenic pathway of the disease. Several genetic and biochemical events are linked to AD development, with oxidative stress being one of them. Due to the scarcity of drugs aimed at treating AD, antioxidant compounds are increasingly studied as therapeutic targets for the disease. In this study, we investigate the antioxidant and anti-Alzheimer potential of the Tetragonisca angustula (Jataí) pollen extract in a Drosophila melanogaster Alzheimer's model. For this purpose, we utilized a D. melanogaster AD-like model, which expresses genes related to the amyloidogenic pathway of Alzheimer's disease. We explored the floral origin of the collected pollen, conducted phytochemical prospecting, and evaluated its antioxidant capacity in vitro. In vivo experiments involved assessing the survival and climbing ability of the D. melanogaster AD-like model with various concentrations of the pollen extract. Our findings revealed that the pollen extract of Tetragonisca angustula exhibits a significant antioxidant response and high concentrations of important phytochemicals, such as flavonoids and polyphenols. Furthermore, it enhanced the survival rate of D. melanogaster, and across all concentrations tested, it improved the climbing ability of the flies after 15 days of treatment with methanolic pollen extract. Additionally, the pollen extract reduced the neurodegeneration index in histopathological analysis. Thus, our study demonstrates the potential of Tetragonisca angustula pollen as an important subject for further investigation, aiming to isolate molecules that could potentially serve as therapeutic targets for Alzheimer's disease.

Investigating academic performance and perceptions of human physiology and exercise physiology courses among undergraduate students of physical education at a Brazilian public university.

PURPOSE: To compare the academic performance of undergraduate students in physical education who studied exercise physiology before and after studying human physiology and investigate students' perceptions of human physiology and exercise physiology courses. METHODS: This study included 311 undergraduate students pursuing a bachelor's degree in physical education. Participants were divided into two groups: those who had previously attended and completed the human physiology course (group 1, n = 212, 68.2%) and those who had not previously attended or had attended but failed the human physiology course (group 2, n = 99, 31.8%). The prevalence ratio (PR) and 95% confidence interval (95% CI) were calculated using a Poisson regression model with a robust variance estimator. The second aim comprised 67 students with bachelor's degrees in physical education who completed an electronic questionnaire about their perceptions of human physiology and exercise physiology curriculum. RESULTS: Compared with those who attended human physiology and passed, those who had not previously attended or had attended but failed the human physiology course have a higher PR of 2.37 (95% CI, 1.68-3.34) for failing exercise physiology. Regarding the students' perceptions of human physiology and exercise physiology courses, most students reported that they were challenging (58.2% and 64.2%, respectively), but they also recognized the importance of these courses for professional practice (59.7% and 85.1%, respectively). CONCLUSION: Human physiology should be considered a prerequisite for an undergraduate course leading to a bachelor's degree in physical education. Furthermore, students considered human physiology and exercise physiology courses important yet challenging. Therefore, continuous student assessment is vital for improving the teaching-learning process.

Comparison of nutritional status and growth curves of children and adolescents in the city of Goiânia, Goiás: cross-sectional study

ABSTRACT BACKGROUND: Nutritional status and growth curves can affect cognitive development, increase the risk of infection, and contribute to the development of chronic diseases. Its etiology is related to food, socioeconomic, and maternal conditions. However, to date, no data on these parameters exist in the state of Goiás, Brazil. OBJECTIVE: To compare the nutritional status and growth curves of children and adolescents in the city of Goiânia, Goiás, Brazil. DESIGN AND SETTING: This was a cross-sectional study. A total of 529 individuals were recruited from a primary health center in the municipality. METHODS: To assess nutritional status, the sample was divided into three categories: 3-4, 5-10, and 11-19 years, with z-score classification considering body mass index for age. The classification of growth curves was performed considering the median height values for age, assuming two references: (a) young Brazilian population and (b) one recommended for international use. The independent sample T-test was used to compare anthropometric variables. RESULTS: The results showed that the classification of eutrophics represents a predominant percentage between both sexes (men: 03-04 = 55.4%; 05-10 = 57.6%; 11-19 = 53.5 % and women: 03-04 = 53.5%; 05-10 = 63.9%; 11-19 = 56.9%), and growth curves showed differences in specific periods in both sexes. CONCLUSIONS: It can be concluded that children and adolescents from the city of Goiânia present as predominance the eutrophic nutritional status, followed by the risk of overweight, underweight, obesity, and malnutrition of both sexes.

Fatores de risco psicossociais relacionados ao trabalho: uma análise contemporânea / Work-related psychosocial risk factors: a contemporary analysis

Resumo Introdução: nos debates sobre a proteção e a promoção da saúde nos contextos laborais, o tema dos fatores psicossociais relacionados ao trabalho (FPRT) tem se destacado. Objetivo: demonstrar que a ausência da tematização do antagonismo e do conflito estrutural entre capital e trabalho, bem como a captura da temática pela lógica gerencialista neoliberal, produz o empobrecimento do debate e o enfraquecimento de iniciativas voltadas para a transformação do contexto laboral. Método: a reflexão é realizada a partir de revisão da literatura, tendo como referencial o materialismo histórico. Resultados: as formulações de políticas, instrumentos e medidas destinadas à proteção da saúde dos trabalhadores, gestadas nos marcos ideológicos do regime de acumulação capitalista e da governamentalidade neoliberal, convertem-se em compreensões e intervenções que, longe de transformarem as situações concretas de trabalho, mascaram o papel exercido pelo trabalho em relação à saúde dos trabalhadores, consagram as ações voltadas aos indivíduos, arrefecem as lutas sociais e ampliam as pressões sobre os trabalhadores. Conclusão: o enfrentamento dos riscos psicossociais não deve se limitar à mitigação desses riscos, mas sim encontrar seus propósitos e seus fundamentos em um horizonte teórico-prático que descortine a necessidade de superação da própria economia capitalista.

Abstract Introduction: work-related psychosocial factors have stood out in debates concerning health protection and promotion in occupational contexts. Objective: this essay demonstrates how the lack of thematic exploration regarding the antagonism and structural conflict between capital and labor, as well as its co-optation by neoliberal managerial logic, impoverishes the debate and weakens initiatives aimed at transforming the work environment. Method: a literature review was conducted using historical materialism as a theoretical framework. Results: policies, instruments, and measures formulated to protect workers' health developed under the ideological framework of capitalist accumulation and neoliberal governmentality become understandings and interventions that, far from transforming actual work situations, mask the role played by work in occupational health. They consecrate actions focused on individuals, dampen social struggles, and increase pressure on workers. Conclusion: addressing psychosocial risks should not be limited to mitigating them; rather, it should find its purposes and foundations in a theoretical-practical horizon that unveils the need to overcome the capitalist economy itself.

Susceptibility of solid organ transplant recipients to viral pathogens with zoonotic potential: A mini-review

ABSTRACT A substantial number of zoonotic diseases are caused by viral pathogens, representing a significant menace to public health, particularly to susceptible populations, such as pregnant women, the elderly, and immunocompromised individuals. Individuals who have undergone solid organ transplantation frequently experience immunosuppression, to prevent organ rejection, and, thus are more prone to opportunistic infections. Furthermore, the reactivation of dormant viruses can threaten transplant recipients and organ viability. This mini-review examines the up-to-date literature covering potential zoonotic and organ rejection-relevant viruses in solid organ transplant recipients. A comprehensive list of viruses with zoonotic potential is highlighted and the most important clinical outcomes in patients undergoing transplantation are described. Moreover, this mini-review calls attention to complex multifactorial events predisposing viral coinfections and the need for continuous health surveillance and research to understand better viral pathogens' transmission and pathophysiology dynamics in transplanted individuals.

Acute effects of moderate-intensity continuous physical exercise performed with different amounts of muscle mass on executive function in healthy young adults: a randomized trial.

We examined the effect of amount of muscle mass involved in moderate-intensity continuous physical exercise on executive function. To this end, fifty-five participants completed two acute physical exercise sessions on an airbike ergometer using the upper and lower limbs simultaneously and only the upper limbs, and a resting control session in a randomized order. The physical exercise session lasted 30 min and was performed at moderate intensity (between 64 %-76 % of maximal heart rate evaluated in graded maximal exercise testing). Participants took the Stroop test (congruent and incongruent trials) before and after the sessions to assess executive performance. For the congruent trial, both physical exercise interventions improved executive function performance (pre vs. post, p-value = 0.002 and 0.003 for physical exercise with upper limbs and physical exercise with upper and lower limbs, respectively). Furthermore, executive function performance was higher after the physical exercise interventions than after the control session (p-value = 0.002 and 0.004 for physical exercise with upper limbs and physical exercise with upper and lower limbs, respectively). For the incongruent trial, both physical exercise interventions also improved executive function performance (pre vs. post, p-value < 0.001 for physical exercise with upper limbs and physical exercise with upper and lower limbs, respectively). However, there were no significant differences after both physical exercise interventions and resting control session (p-value = 0.175). Executive function (congruent trial) was positively impacted by acute aerobic physical exercise regardless of the amount of muscle mass involved (upper limbs or upper plus lower limbs). Therefore, we recommend aerobic physical exercise with less or more muscle mass involved to improve cognitive function.