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1.
SciELO Preprints; set. 2024.
Preprint en Portugués | SciELO Preprints | ID: pps-9698

RESUMEN

Introduction: Brazil stands out as the second country that performs the most organ transplant surgeries (approximately 19,000 procedures performed until August 2023), second only to the United States, according to the Ministry of Health. Although the number of transplants performed is high when compared to other world averages, the huge waiting list for a compatible donor is still a challenge to be overcome. Objectives: This article aims to describe the rates of intention to donate organs among health students in the city of Jaru, analyze which factors impact this decision, as well as assess the knowledge of academics on the subject. Material and Methods: 271 students were interviewed from the Nursing, Medicine, Pharmacy, Psychology and Dentistry courses at Faculdade FIMCA Unicentro and Veterinary Medicine at Instituto Federal de Rondônia (IFRO campus Jaru), who volunteered to answer a 14-question questionnaire. After the survey was applied, the data were tabulated and analyzed. Results/development and discussion: It was observed that 55.4% of the interviewees intend to donate their organs after death and 31.4% have not yet decided. Furthermore, regarding their knowledge on the subject, 8.5% evaluated it as "excellent", 26.2% as "good", 50.6% as "average", 12.2% as "poor" and 2.6% as "terrible". Furthermore, 33.9% do not trust the diagnosis of brain death, and only 53.9% know the risks involved in living organ transplantation. Conclusion: Based on the data obtained, it is concluded that intervention is necessary to improve students' knowledge on the subject, in order to increase adherence rates to the practice capable of saving and improving the quality of life of eligible patients.


Introdução: O Brasil se destaca como o segundo país que mais realiza cirurgias de transplante de órgãos (cerca de 19.000 procedimentos executados até agosto de 2023), ficando atrás apenas dos Estados Unidos, segundo o Ministério da Saúde. Apesar dos números de transplantes realizados serem elevados ao comparar com as demais médias mundiais, a imensa fila de espera por um doador compatível ainda é um desafio a ser superado. Objetivos: O presente artigo tem como objetivo descrever as taxas de intenção de doação de órgãos entre estudantes da área da saúde da cidade Jaru, analisar quais fatores impactam nessa decisão, bem como avaliar o conhecimento dos acadêmicos acerca do assunto. Material e Métodos: Foram entrevistados 271 estudantes dentre os cursos de Enfermagem, Medicina, Farmácia, Psicologia e Odontologia da Faculdade FIMCA Unicentro e Medicina Veterinária do Instituto Federal de Rondônia (IFRO campus Jaru), que se apresentaram como voluntários para responder um questionário de 14 perguntas. Após a aplicação do inquérito, os dados foram tabulados e analisados. Resultados/desenvolvimento e discussão: Pôde-se observar, então, que 55,4% dos entrevistados pretendem doar seus órgãos após a morte e 31,4% ainda não decidiram. Ademais, sobre o conhecimento que possuem do tema 8,5% avaliou como "ótimo", 26,2% "bom", 50,6% "regular", 12,2% "ruim" e 2,6% como "péssimo". Além disso, 33,9% não confiam no diagnóstico de morte encefálica, e apenas 53,9% sabem os riscos presentes no transplante intervivos. Conclusão: A partir dos dados obtidos, conclui-se que é necessário intervenção para aprimorar o conhecimento dos alunos a respeito do tema, a fim de elevar as taxas de adesão à prática capaz de salvar e melhorar a qualidade de vida dos enfermos aptos.

2.
Polymers (Basel) ; 16(17)2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39274178

RESUMEN

In response to heightened environmental awareness, various industries, including the civil and automotive sector, are contemplating a shift towards the utilization of more sustainable materials. For adhesive bonding, this necessitates the exploration of materials derived from renewable sources, commonly denoted as bio-adhesives. This study focuses on a bio-adhesive L-joint, which is a commonly employed configuration in the automotive sector for creating bonded structural components with significant bending stiffness. In this investigation, the behavior of joints composed of pine wood and bio-based adhesives was studied. Two distinct configurations were studied, differing solely in the fiber orientation of the wood. The research combined experimental testing and finite element modeling to analyze the strength of the joints and determine their failure mode when subjected to tensile loading conditions. The findings indicate that the configuration of the joint plays a crucial role in its overall performance, with one of the solutions demonstrating higher strength. Additionally, a good degree of agreement was observed between the experimental and numerical analyses for one of the configurations, while the consideration of the maximum principal stress failure predictor (MPSFP) proved to accurately predict the location for crack propagation in both configurations.

3.
Angew Chem Int Ed Engl ; : e202413089, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39265063

RESUMEN

Polymersomes are synthetic vesicles that mimic the architecture of cellular compartments such as the cell membrane and organelles. These biomimetic compartments facilitate the creation of cell-like chemical systems, including microreactors and synthetic organelles. However, the construction of hierarchical multi-compartment systems remains challenging and typically requires the encapsulation of pre-formed vesicles within a host compartment. Here, we report the formation of multicompartment polymersomes with a vesicle-in-vesicle architecture achieved through self-division induced by short peptides incorporated into the vesicle membrane. A phenylalanine-phenylalanine-methionine (FFM) tripeptide was designed and encapsulated into the polymersome via microfluidics. We demonstrate that vesicle self-division occurs due to peptide incorporation into the membrane in response to pH changes. This self-division creates internal vesicles capable of colocalizing enzymes. The hybrid polymer-peptide system described here provides a straightforward method for developing subcompartmentalized systems, paving the way for engineering microreactors with life-like properties.

4.
Res Q Exerc Sport ; : 1-6, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39249506

RESUMEN

The present study aimed to verify the effect of acute nitrate supplementation on oxidative, phosphocreatine, and glycolytic energy contribution (COXI, CPCr, and CLAC, respectively) during a high-intensity intermittent exercise (HIIE). Fifteen physically active subjects were submitted to incremental running test on a treadmill and two random HIIE (10 × 1 min at maximal aerobic speed with 1 min of passive recovery) in the following conditions: sodium nitrate (SN) or Placebo (PL). Repeated measure ANOVA was used to compare COXI, and CPCr within the 10 efforts. Student t test was used to compare total COXI, CPCr, CLAC, as well oxidative and non-oxidative contribution. Considering the 10 efforts, COXI presented the main effect for condition (F = 16.7; p = .001; SN: 1.9 ± 0.1 L; PL: 1.6 ± 0.1 L), and no interaction effect (F = 0.9; p = .415), while CPCr presented effect for condition (F = 13.4; p = .003; SN: 1.2 ± 0.1; PL: 1.4 ± 0.8 L), and no interaction (F = 1.2; p = .317). Total oxidative contribution were higher (p < .001) after SN (19.1 ± 3.4 L) than Placebo (16.7 ± 3.1 L), while total CPCr were lower (p = .002) after SN (12.4 ± 2.5 L) than PL (14.1 ± 2.6 L). Total energy contribution were not different between trials. Acute dose of SN supplementation improved oxidative contribution during HIIE, and reduced CPCr. Higher COXI is likely related to increased oxygen kinetics, while the lower CPCr might be related to the improved energetic efficiency.

5.
Int J Mol Sci ; 25(16)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39201325

RESUMEN

Breast cancer (BC) remains a significant global health concern, with neoadjuvant chemotherapy (NACT) offering preoperative benefits like tumor downstaging and treatment response assessment. However, identifying factors influencing post-NACT treatment response and survival outcomes is challenging. Metabolomic approaches offer promising insights into understanding these outcomes. This study analyzed the serum of 80 BC patients before and after NACT, followed for up to five years, correlating with disease-free survival (DFS) and overall survival (OS). Using untargeted nuclear magnetic resonance (NMR) spectroscopy and a novel statistical model that avoids collinearity issues, we identified metabolic changes associated with survival outcomes. Four metabolites (histidine, lactate, serine, and taurine) were significantly associated with DFS. We developed a metabolite-related survival score (MRSS) from these metabolites, stratifying patients into low- and high-risk relapse groups, independent of classical prognostic factors. High-risk patients had a hazard ratio (HR) for DFS of 3.42 (95% CI 1.51-7.74; p = 0.003) after adjustment for disease stage and age. A similar trend was observed for OS (HR of 3.34, 95% CI 1.64-6.80; p < 0.001). Multivariate Cox proportional hazards analysis confirmed the independent prognostic value of the MRSS. Our findings suggest the potential of metabolomic data, alongside traditional markers, in guiding personalized treatment decisions and risk stratification in BC patients undergoing NACT. This study provides a methodological framework for leveraging metabolomics in survival analyses.


Asunto(s)
Neoplasias de la Mama , Metabolómica , Terapia Neoadyuvante , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , Persona de Mediana Edad , Metabolómica/métodos , Adulto , Pronóstico , Anciano , Supervivencia sin Enfermedad , Metaboloma , Quimioterapia Adyuvante , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/metabolismo , Modelos de Riesgos Proporcionales
6.
Lasers Med Sci ; 39(1): 207, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093490

RESUMEN

To review current literature and synthesize clinical outcomes related to different low-level laser techniques as a complement to basic periodontal therapy (BPT). Electronic searches were conducted in PubMed, Cochrane, and Scopus, and clinical trials published from January 2013 to August 2023 using photobiomodulation as a complement to basic periodontal therapy, with a clear description of the laser technique, were included. The risk of bias was assessed using the Joanna Briggs Institute Critical Assessment Checklist. Estimates of interest were calculated using random effects meta-analyses. A total of 947 references were retrieved, and 22 studies were included for qualitative synthesis. Ten studies used intrasulcular laser techniques, with 89% using infrared wavelength, and 12 studies used transgingival techniques, with 61.5% using red wavelength. The frequency of photobiomodulation after BPT ranged from 1 to 9 sessions, with follow-up periods ranging from 5 days to 12 months. Risk of bias was considered low in 16 studies and moderate in six studies. Meta-analysis of 13 studies showed that BPT reduced probing depth at 4-, 12- and 24-weeks post-treatment, and improved clinical level attachment at 6-, 12- and 24-weeks post-treatment. Studies suggest that photobiomodulation may be a valuable complement in the treatment of periodontitis, especially using transgingival application technique.


Asunto(s)
Terapia por Luz de Baja Intensidad , Humanos , Terapia por Luz de Baja Intensidad/métodos , Enfermedades Periodontales/radioterapia , Enfermedades Periodontales/terapia , Resultado del Tratamiento
7.
Biomacromolecules ; 25(9): 5468-5488, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39178343

RESUMEN

Biomolecular condensates are dynamic liquid droplets through intracellular liquid-liquid phase separation that function as membraneless organelles, which are highly involved in various complex cellular processes and functions. Artificial analogs formed via similar pathways that can be integrated with biological complexity and advanced functions have received tremendous research interest in the field of synthetic biology. The coacervate droplet-based compartments can partition and concentrate a wide range of solutes, which are regarded as attractive candidates for mimicking phase-separation behaviors and biophysical features of biomolecular condensates. The use of peptide-based materials as phase-separating components has advantages such as the diversity of amino acid residues and customized sequence design, which allows for programming their phase-separation behaviors and the physicochemical properties of the resulting compartments. In this Perspective, we highlight the recent advancements in the design and construction of biomimicry condensates from synthetic peptides relevant to intracellular phase-separating protein, with specific reference to their molecular design, self-assembly via phase separation, and biorelated applications, to envisage the use of peptide-based droplets as emerging biomedical delivery vehicles.


Asunto(s)
Condensados Biomoleculares , Péptidos , Péptidos/química , Condensados Biomoleculares/química , Humanos , Materiales Biomiméticos/química , Biomimética/métodos , Sistemas de Liberación de Medicamentos/métodos , Separación de Fases
8.
bioRxiv ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39211178

RESUMEN

Genome editing with RNA-guided DNA binding factors carries risk of off-target editing at homologous sequences. Genetic variants may introduce sequence changes that increase homology to a genome editing target, thereby increasing risk of off-target editing. Conventional methods to verify candidate off-targets rely on access to cells with genomic DNA carrying these sequences. However, for candidate off-targets associated with genetic variants, appropriate cells for experimental verification may not be available. Here we develop a method, Assessment By Stand-in Off-target LentiViral Ensemble with sequencing (ABSOLVE-seq), to integrate a set of candidate off-target sequences along with unique molecular identifiers (UMIs) in genomes of primary cells followed by clinically relevant gene editor delivery. Gene editing of dozens of candidate off-target sequences may be evaluated in a single experiment with high sensitivity, precision, and power. We provide an open-source pipeline to analyze sequencing data. This approach enables experimental assessment of the influence of human genetic diversity on specificity evaluation during gene editing therapy development.

9.
Polymers (Basel) ; 16(16)2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39204504

RESUMEN

While most academic studies focus on the properties of cured joints, this research addresses the manufacturing process of hybrid joints in their uncured state. Hybrid joints that combine adhesive bonding with pre-tensioned bolts exhibit superior mechanical performance compared to exclusively bonded or bolted joints. However, the adhesive flow during manufacturing in hybrid joints often results in a nonuniform adhesive thickness, where obtaining an exact thickness is crucial for accurate load capacity predictions. This paper presents experiments involving three different adhesives, providing precise measurements of the adhesive layer thickness distribution, which served as a reference when evaluating and validating the subsequent numerical predictions. The numerical predictions were performed using computational fluid dynamics (CFD) to model the flow behavior of the adhesives during the bonding process and their interactions with the metal substrates. The CFD predictions of the adhesive layer thickness showed good agreement with the experimental data, with the relative differences between the average experimental and numerical thickness values ranging from 4.07% to 27.1%. The results were most accurate for the adhesive with sand particles, whose particles remained intact, ensuring that the adhesive's rheology remained unchanged. The results highlight the importance of the rheological behavior of the adhesive in the final distribution of the adhesive layer thickness, thereby expanding the understanding of these joints.

10.
Polymers (Basel) ; 16(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39204602

RESUMEN

This study focuses on the prediction of the fracture mechanics behaviour of a highly flexible adhesive (with a tensile elongation of 90%), since this type of adhesive is becoming widely used in automotive structures due to their high elongation at break and damping capacity. Despite their extensive applications, the understanding of their fracture mechanics behaviour under varying loading rates and temperatures remains limited in the literature. In addition, current prediction models are also unable to accurately predict their behaviour due to the complex failure mechanism that such bonded joints have. This study aims to determine whether a simple triangular cohesive zone model (CZM), which predefines the crack path, can reproduce the load-displacement curves of adhesives under various temperatures and strain rates. To achieve this, a calibrated CZM is used, adapting the model for reference joints and then validating it with independent test results conducted in a wide range of loading and environmental conditions. The tests were performed at speeds between 0.2 and 6000 mm/min and at three different temperatures ranging from -30 °C to 60 °C. Mode I fracture toughness was measured using the DCB (double cantilever beam) specimens. Using a simple triangular CZM may not be optimal for predicting the mechanical response of highly flexible adhesives with complex failure mechanisms and multiple crack paths. However, by correctly adjusting the cohesive zone properties for a limited set of reference conditions, it is possible to accurately predict the mechanical response of these joints across various test speeds and temperatures, significantly reducing costs and effort.

11.
J Clin Monit Comput ; 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39031230

RESUMEN

PURPOSE: An FDA-approved non-invasive intracranial pressure (ICP) monitoring system enables the assessment of ICP waveforms by revealing and analyzing their morphological variations and parameters associated with intracranial compliance, such as the P2/P1 ratio and time-to-peak (TTP). The aim of this study is to characterize intracranial compliance in healthy volunteers across different age groups. METHODS: Healthy participants, both sexes, aged from 9 to 74 years old were monitored for 5 min in the supine position at 0º. Age was stratified into 4 groups: children (≤ 7 years); young adults (18 ≤ age ≤ 44 years); middle-aged adults (45 ≤ age ≤ 64 years); older adults (≥ 65 years). The data obtained was the non-invasive ICP waveform, P2/P1 ratio and TTP. RESULTS: From December 2020 to February 2023, 188 volunteers were assessed, of whom 104 were male, with a median (interquartile range) age of 41 (29-51), and a median (interquartile range) body mass index of 25.09 (22.57-28.04). Men exhibited lower values compared to women for both the P2/P1 ratio and TTP (p < 0.001). There was a relative rise in both P2/P1 and TTP as age increased (p < 0.001). CONCLUSIONS: The study revealed that the P2/P1 ratio and TTP are influenced by age and sex in healthy individuals, with men displaying lower values than women, and both ratios increasing with age. These findings suggest potential avenues for further research with larger and more diverse samples to establish reference values for comparison in various health conditions. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (RBR-9nv2h42), retrospectively registered 05/24/2022. UTN: U1111-1266-8006.

12.
Eur J Nutr ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967674

RESUMEN

PURPOSE: Nut-enriched diets are related to improve lipid and inflammatory biomarkers in meta-analyses in the context of primary cardiovascular prevention. However, primary studies on secondary cardiovascular prevention are scarce and controversial. This systematic review and meta-analysis aimed to evaluate the effect of nut supplementation on lipid and inflammatory profiles in individuals with atherosclerotic cardiovascular disease, and the frequency of adverse events. METHODS: Six databases were used for research: PubMed, EMBASE, BVS, Cochrane Library, Web of Science, and ClinicalTrials.gov, until February 2023, with no language restrictions. We performed random-effects meta-analyses to compare nut-enriched diets vs. control diets for pre-post intervention changes. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system assessed the evidence's certainty. RESULTS: From the 5187 records identified, eight publications containing data referring to five randomized clinical trials involving 439 participants were included in the final analyses. The nuts evaluated were almonds, pecans, Brazil nuts, and mixed nuts, with doses ranging between 5 g and 85 g (median: 30 g/day). The intervention time varied between 6 and 12 weeks. Compared to nut-free diets, nut intake did not have a statistically significant effect on lipid profile biomarkers, except on the atherogenic index (MD: -0.32 [95% CI -0.58 to -0.06], I2 = 0% - moderate certainty of the evidence). Similarly, there was no effect of nuts on inflammatory profile biomarkers. It was not possible to aggregate data on adverse events. CONCLUSIONS: Nut supplementation did not change lipid and inflammatory profiles in the secondary cardiovascular prevention setting.

14.
Polymers (Basel) ; 16(13)2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-39000643

RESUMEN

Natural fiber reinforcements have the potential to enhance mechanical properties, thereby improving performance and durability in various applications. In this study, we comprehensively evaluated the impact of environmental degradation over 120 days on reprocessed polypropylene (PP) reinforced with corn husk fiber (CHF) composites. The manufactured systems underwent rigorous analysis using various techniques, including Fourier transform infrared spectroscopy, thermogravimetric analysis, optical microscopy, scanning electron microscopy, and tensile testing. These analyses revealed that climatic conditions significantly influenced (p < 0.05) the mechanical properties of all systems. Photodegradation led to surface morphological changes and chemical structures. Regardless, adding CHF filler proved a key factor, as it allowed for less susceptibility to environmental degradation than the reprocessed matrix. These findings, therefore, provide robust evidence supporting the feasibility of using CHF composites for manufacturing agricultural containers.

15.
Biomedicines ; 12(6)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38927396

RESUMEN

The aim of this study was to evaluate the effect of the combination of neovestitol-vestitol (CNV) compounds obtained from Brazilian red propolis on the microbiological profile of a mature multispecies subgingival biofilm. The biofilm with 32 bacterial species associated with periodontitis was formed for seven days using a Calgary device. Treatment with CNV (1600, 800, 400, and 200 µg/mL), amoxicillin (54 µg/mL), and vehicle control was performed for 24 h on the last day of biofilm formation. Biofilm metabolic activity and DNA-DNA hybridization (checkerboard) assays were performed. The groups treated with CNV 1600 and amoxicillin reduced 25 and 13 species, respectively, compared to the control vehicle treatment (p ≤ 0.05); both reduced P. gingivalis, while only CNV reduced T. forsythia. When the data from the two treatments (CNV and AMOXI) were compared, a statistically significant difference was observed in 13 species, particularly members of Socransky's orange complex. Our results showed that CNV at 1600 µg/mL showed the best results regarding the metabolic activity of mature biofilms and obtained a reduction in species associated with the disease, such as T. forsythia, showing a better reduction than amoxicillin. Therefore, CNV seems to be a promising alternative to eradicate biofilms and reduce their pathogenicity.

16.
Anal Chem ; 96(22): 8893-8904, 2024 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-38782403

RESUMEN

Metabolites from feces provide important insights into the functionality of the gut microbiome. As immediate freezing is not always feasible in gut microbiome studies, there is a need for sampling protocols that provide the stability of the fecal metabolome and microbiome at room temperature (RT). Here, we investigated the stability of various metabolites and the microbiome (16S rRNA) in feces collected in 95% ethanol (EtOH) and commercially available sample collection kits with specific preservatives OMNImet•GUT/OMNIgene•GUT. To simulate field-collection scenarios, the samples were stored at different temperatures at varying durations (24 h + 4 °C, 24 h RT, 36 h RT, 48 h RT, and 7 days RT) and compared to aliquots immediately frozen at -80 °C. We applied several targeted and untargeted metabolomics platforms to measure lipids, polar metabolites, endocannabinoids, short-chain fatty acids (SCFAs), and bile acids (BAs). We found that SCFAs in the nonstabilized samples increased over time, while a stable profile was recorded in sample aliquots stored in 95% EtOH and OMNImet•GUT. When comparing the metabolite levels between aliquots stored at room temperature and at +4 °C, we detected several changes in microbial metabolites, including multiple BAs and SCFAs. Taken together, we found that storing samples at RT and stabilizing them in 95% EtOH yielded metabolomic results comparable to those from flash freezing. We also found that the overall composition of the microbiome did not vary significantly between different storage types. However, notable differences were observed in the α diversity. Altogether, the stability of the metabolome and microbiome in 95% EtOH provided results similar to those of the validated commercial collection kits OMNImet•GUT and OMNIgene•GUT, respectively.


Asunto(s)
Etanol , Heces , Microbioma Gastrointestinal , Metabolómica , Manejo de Especímenes , Humanos , Etanol/química , Heces/microbiología , Heces/química , ARN Ribosómico 16S , Manejo de Especímenes/métodos , Temperatura
17.
J Hypertens ; 42(7): 1173-1183, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38690885

RESUMEN

OBJECTIVE: To evaluate the effectiveness of a nutritional strategy based on two components and adapted for the public health system on blood pressure, cardiometabolic features, self-care, qualify of life and diet quality in individuals with hypertension. METHODS: NUPRESS was an open-label, parallel-group, superiority randomized controlled clinical trial in which participants at least 21 years with hypertension and poorly controlled blood pressure were randomly assigned (1 : 1 allocation ratio) to either an individualized dietary prescription according to nutritional guidelines (control group, n  = 205); or a two-component nutrition strategy, including a goal-directed nutritional counseling and mindfulness techniques (NUPRESS [intervention] group, n  = 205). Primary outcomes were SBP (mmHg) after 24 weeks of follow up and blood pressure control, defined as either having SBP more than 140 mmHg at baseline and achieving 140 mmHg or less after follow-up or having SBP 140 mmHg or less at baseline and reducing the frequency of antihypertensive drugs in use after follow-up. RESULTS: In total, 410 participants were randomized and submitted to an intention-to-treat analysis regarding primary outcomes. Both groups decreased blood pressure, but after adjusting for baseline values, there was no significant difference between them on SBP [intervention-control difference: -0.03 (-3.01; 2.94); P  = 0.98] nor blood pressure control [odds ratio 1.27 (0.82; 1.97); P  = 0.28]. No differences between groups were also detected regarding secondary and tertiary outcomes. CONCLUSION: There was no difference between a two-component nutritional strategy and an established dietary intervention on blood pressure in participants with hypertension.


Asunto(s)
Presión Sanguínea , Hipertensión , Humanos , Hipertensión/dietoterapia , Hipertensión/terapia , Masculino , Femenino , Persona de Mediana Edad , Anciano , Resultado del Tratamiento , Adulto , Salud Pública , Antihipertensivos/uso terapéutico
18.
Materials (Basel) ; 17(9)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38730902

RESUMEN

This study experimentally investigates the influence of metal chips and glass fibers on the mode I fracture toughness, energy absorption, and tensile strength of polymer concretes (PCs) manufactured by waste aggregates. A substantial portion of the materials employed in manufacturing and enhancing the tested polymer concrete are sourced from waste material. To achieve this, semi-circular bend (SCB) samples were fabricated, both with and without a central crack, to analyze the strength and fracture behavior of the composite specimens. The specimens incorporated varying weight percentages comprising 50 wt% coarse mineral aggregate, 25 wt% fine mineral aggregate, and 25 wt% epoxy resin. Metal chips and glass fibers were introduced at 2, 4, and 8 wt% of the PC material to enhance its mechanical response. Subsequently, the specimens underwent 3-point bending tests to obtain tensile strength, mode I fracture toughness, and energy absorption up to failure. The findings revealed that adding 4% brass chips along with 4% glass fibers significantly enhanced energy absorption (by a factor of 3.8). However, using 4% glass fibers alone improved it even more (by a factor of 10.5). According to the results, glass fibers have a greater impact than brass chips. Introducing 8% glass fibers enhanced the fracture energy by 92%. However, in unfilled samples, aggregate fracture and separation hindered crack propagation, and filled samples presented added barriers, resulting in multiple-site cracking.

19.
Appl Radiat Isot ; 210: 111366, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38796997

RESUMEN

A systematic study of the distribution of the Naturally Occurring Radioactivity in stone dust and crushed stone, has been carried out with an objective of establishing reliable baseline data on the radiation level and hence to evaluate hazard indices approach and the production of radioactive heat (RHP) due to radiation exposure to the workers and to the inhabitants of the studied area. Twenty-six samples have been collected from different locations in the State of Rio de Janeiro (Brazil). To calculate the specific activity, gamma ray spectrometry and a detector of High Purity Germanium (HPGe; Canberra, 30% relative efficiency) was used. The activity concentration of 238U, 226Ra 232Th and 40K ranged from 29.3 ± 18.6 to 206.8 ± 21.5 Bq kg-1, 30.3 ± 1.0 to 134.3 ± 1.8, 27.9 ± 0.7 to 86.2 ± 0.9 Bq kg-1, and 734.9 ± 35.1 to 1204.8 ± 53.5 Bq kg-1, respectively. The mean values of the Iex, Iin, Iγ, Iα, AUI, IRP112Rn, IPA, IPI and IYu indices were 0.68 ± 0.09, 0.92 ± 0.12, 0.93 ± 0.12, 0.43 ± 0.07, 0.88 ± 0.20, 1.25 ± 0.21, 0.34 ± 0.05, 0.75 ± 0.10, 0.63 ± 0.08 and 34. ± 6.31, respectively. The average radioactive heat production (RHP) of 2.01 ± 0.28 µ Wm-3 was above the values found in the literature, which may contribute to the heat flow in the study area because the raw materials that make up the samples showed a high value of environmental radioactivity. The Brazilian Hazard Index to assess the radiological risk of crushed stone and stone dust was created and the average value was 0.74 ± 0.10, a value below 1, which means only moderate control over the use of these materials, with no indication of restriction to the its use.

20.
Materials (Basel) ; 17(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38793454

RESUMEN

The use of thin-ply composite materials has rapidly increased due to their tailorable mechanical properties and design flexibility. Considering an adhesively bonded composite joint, peel stress stands out as a key contributor leading to failure among other primary stress factors. Therefore, the reinforcement of carbon fiber-reinforced polymer (CFRP) laminates throughout the thickness could be considered as an approach to improve the joint strength. Using thin plies locally between the conventional CFRP layers in a laminate can enhance the strength, as the sudden change in stiffness means that the load transfer is not monotonous. Consequently, the following study examined the effect of altering thin plies gradually throughout the thickness on the behaviour of the CFRP laminates when subjected to transverse tensile loading. To achieve this goal, the CFRP laminates were gradually modified by using different commercially accessible prepreg thin plies, leading to an improved overall structural performance by reducing stress concentrations. Besides conducting an experimental study, a numerical assessment was also carried out utilizing Abaqus software with a Representative Volume Element (RVE) at the micro scale. The comparison of reference configurations, which involved various thin plies with different thicknesses and traditional CFRP laminates, with the suggested gradual configuration, demonstrated a notable enhancement in both strength and material cost. Furthermore, the proposed RVE model showed promising capability in accurately forecasting the strength of fabricated laminates.

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