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1.
Antibiotics (Basel) ; 13(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38667015

RESUMO

This study aimed to develop a polymeric matrix of polyamide-6 (P6) impregnated with trimetaphosphate (TMP) nanoparticles and silver nanoparticles (AgNPs), and to evaluate its antimicrobial activity, surface free energy, TMP and Ag+ release, and cytotoxicity for use as a support in dental tissue. The data were subjected to statistical analysis (p < 0.05). P6 can be incorporated into TMP without altering its properties. In the first three hours, Ag+ was released for all groups decorated with AgNPs, and for TMP, the release only occurred for the P6-TMP-5% and P6-TMP-10% groups. In the inhibition zones, the AgNPs showed activity against both microorganisms. The P6-TMP-2.5%-Ag and P6-TMP-5%-Ag groups with AgNPs showed a greater reduction in CFU for S. mutans. For C. albicans, all groups showed a reduction in CFU. The P6-TMP groups showed higher cell viability, regardless of time (p < 0.05). The developed P6 polymeric matrix impregnated with TMP and AgNPs demonstrated promising antimicrobial properties against the tested microorganisms, making it a potential material for applications in scaffolds in dental tissues.

2.
Environ Pollut ; 347: 123728, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38458520

RESUMO

Fish is an important source of animal protein for local communities in the Amazon basin, whose food safety must be assured. However, certain potential toxicants elements, can bioaccumulate in fish species, which inhabit anthropogenically polluted waters, ultimately posing a risk to human health. In the present study, the concentrations of nine elements (Al, As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) were determined in raw and cooked samples of eight fish species consumed in Santarém (northern Brazil, Amazon biome). The potential for non- carcinogenic human health risks linked to the consumption of cooked fish were evaluated for adults and children in two different scenarios. Four carnivores, three omnivores and one detritivore, all of them regularly marketed and consumed by the Santarém population, were the target species. The safety reference values set by national and international guidelines for humans, in both raw and cooked preparations, were used. In most cases, the cooking process showed a trend to increase elements concentrations compared to raw samples, however the differences were not significant. Moreover, the risk assessment showed danger for children in relation to Hg from the consumption of fish, in both scenarios evaluated. For adults, in one of the scenarios, there was a health risk associated to Hg as a result of carnivorous fish consumption. In a context of combined exposure to all elements, children were at risk when consuming fish, especially carnivorous and omnivorous species. For adults, the mixture of elements posed a risk to health human only for carnivorous fish consumption. The results reveal an environmental scenario of Hg contamination, which requires monitoring actions to preserve the aquatic biodiversity and human health in the Brazilian Amazon biome.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Criança , Adulto , Animais , Humanos , Brasil , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Peixes , Mercúrio/análise , Ecossistema , Medição de Risco , Culinária , Metais Pesados/análise
3.
Alcohol Alcohol ; 59(3)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38529709

RESUMO

INTRODUCTION: Alcohol ingestion influences metabolism during a subsequent exercise session, as evidenced by increased blood lactate concentration during fixed-intensity exercise. Therefore, augmented blood concentrations of alcohol may interfere with the anaerobic metabolism during high-intensity, short-duration exercise bout, thereby leading to impaired athletic performance. OBJECTIVE: This study investigated whether the acute ingestion of alcohol as ethanol modulates performance parameters derived from the power-duration relationship in a 3-min all-out cycling test that allows for identifying the power output related to heavy and severe exercise intensities. METHODS: Twenty-four recreationally active cyclists (16 men and 8 women) ingested a beverage containing either 0.4 g ethanol.kg-1 body mass (EtOH) or a placebo (PLA) solution. Thirty minutes following ingestion, they completed a 3-min all-out test to measure power output and determine the end-test power (EP) and the work done above EP (WEP). RESULTS: Alcohol ingestion decreased WEP by 16% (EtOH: 5.6 ± 2.5 kJ vs. PLA: 6.7 ± 2.4 kJ; P = .003) but did not change EP (EtOH: 211 ± 44 W vs. PLA: 212 ± 44 W; P = .671). The alcohol-mediated effect in WEP was not influenced when controlling for participants' sex or accuracy in identifying the beverage ingested. CONCLUSION: Our data indicate that alcohol ingestion impaired the anaerobic work capacity, as evidenced by the reduction in WEP during the 3-min all-out test. Moreover, the ability to exercise at an intensity above the heavy domain may be decreased after ingestion of a moderate alcohol dose.


Assuntos
Teste de Esforço , Exercício Físico , Masculino , Humanos , Feminino , Etanol/farmacologia , Ingestão de Alimentos , Poliésteres
4.
Food Res Int ; 180: 114091, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395568

RESUMO

In recent years, lignin has drawn increasing attention due to its intrinsic antibacterial and antioxidant activities, biodegradability, and biocompatibility. Yet, like several other biogenic structures, its compositional heterogeneity represents a challenge to overcome. In addition, there are few studies regarding food applications of lignin. Herein, we evaluate the antimicrobial and antioxidant effects of lignin from two different sources. These lignins were characterized by attenuated total reflectance Fourier-transform infrared (ATR-FTIR) and hydrogen nuclear magnetic resonance (1H NMR) spectroscopies. Their antibacterial and antioxidant capacities (DPPH and Folin-Ciocalteu methods) were also investigated. Susceptibility tests were performed with the minimal inhibitory (MIC) and bactericidal (MBC) concentrations using the micro-broth dilution technique. Kraft lignin presented higher radical-scavenging and antibacterial activities than alkali lignin, indicating the dependence of antioxidant and antibacterial activities on the precursor biomass. Scanning electron microscopy shows morphologic changes in the bacteria after exposure to lignin, while confocal microscopy suggests that kraft lignin has affinity towards bacterial surfaces and the ability to cause cell membrane destabilization. Lignin inhibited the growth of Staphylococcus aureus and Salmonella Enteritidis in skimmed milk, herein taken as food model. Our results suggest that lignins are promising candidates for green additives to improve quality and safety within the food chain.


Assuntos
Antioxidantes , Lignina , Animais , Lignina/farmacologia , Lignina/química , Antioxidantes/farmacologia , Antioxidantes/química , Leite , Rios , Antibacterianos/farmacologia
5.
Adapt Phys Activ Q ; : 1-17, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316127

RESUMO

Match-related performance analysis in judo Para athletes with visual impairments is important to coaches and staff to identify technical-tactical profiles of their athletes and opponents but also to identify whether there are similar characteristics in each visual class. Thus, this study explores the match-related performance in judo Para athletes and verifies the relationship between performance using the old and new classification systems. The match-derived variables were analyzed using different statistical methods considering a total of 182 matches from the Tokyo 2020 Paralympic Games. The results indicated that performance was affected by sex and degree of impairment. The new classification system seems suitable for grouping Para judo athletes, as it differentiates performance between the two proposed classes (J1 and J2), since athletes from each group compete separately. Furthermore, different variability index measures were correlated with competitive performance, demonstrating a specific performance profile for each sport class in judo.

6.
Vet Parasitol ; 327: 110137, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38278036

RESUMO

The ANESPSAT, a synthetic spilanthol derivative, and its nanoformulation were evaluated against Rhipicephalus microplus and Amblyomma sculptum ticks. ANESPSAT activity was compared with spilanthol and derivatives (ANESPE and others). The compound was synthesized in a gram-scale by a 2-step process, comprising a direct ester amidation and a Horner-Wadsworth- Emmons reaction. The nanoemulsions were produced by coarse homogenization followed by high-energy ultrasonication, in which hydrodynamic diameter, polydispersity index, and zeta potential remained stable. The spilanthol-eugenol hybrid derivatives did not show significant acaricidal activity. ANESPE killed 83% of the R. microplus larvae at 30 mg.mL-1, while ANESPSAT killed 97% at 0.5 mg.mL-1, showing to be the most active compound. Spilanthol and ANESPSAT had similar high mortality rates for tick larvae, with LC50 values of 0.10 and 0.14 mg.mL-1 for R. microplus larvae, and 0.04 and 0.48 mg.mL-1 for A. sculptum larvae, respectively. The efficacy of spilanthol was lower against R. microplus engorged females when compared with ANESPSAT, which was highly effective (>98%) against R. microplus engorged females. The nanoemulsion with ANESPSAT was effective against tick females, preventing egg laying and achieving 100% efficacy at 2.5 mg.mL-1. Spilanthol had only 59% efficacy at 10 mg.mL-1. The results suggest that ANESPSAT, a natural product derivative, could be used in novel formulations for tick management that might be safer and environmentally friendly.


Assuntos
Acaricidas , Rhipicephalus , Feminino , Animais , Acaricidas/farmacologia , Alcamidas Poli-Insaturadas , Larva
7.
An Acad Bras Cienc ; 95(4): e20191114, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126389

RESUMO

Amazonian várzeas are annually flooded for at least five months, which influences the occurence of waterbirds. This study investigates the species richness and composition, and individual abundance of waterbird assemblages in 10 várzea lakes on the lower Amazon River across a seasonal cycle. A total of 7,970 birds belonging to 52 species were recorded. Of these, 25 species were present in all four phases of the cycle, 5 in three phases, 10 in two and 12 during just one phase. Families with the highest species richness were Ardeidae and Scolopacidae. In the dry season, we recorded the highest species richness and the highest total abundance values. Thirteen species showed variation in abundance across the seasonal cycle, most being more abundant in the dry season Variation in species richness, abundance, and composition suggests that research on waterbird assemblages in Amazonian várzeas should consider all phases of the seasonal cycle. Furthermore, the occurrence of several migratory species demonstrates the importance of this region for the conservation of this group. Multi-year monitoring would contribute to a better understanding of the dynamics of Amazonian várzea waterbird assemblages.


Assuntos
Lagos , Rios , Humanos , Animais , Brasil , Estações do Ano , Aves , Ecossistema
8.
Arq. bras. cardiol ; 120(12): e20230338, dez. 2023. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1527801

RESUMO

Resumo Fundamento A utilização do teste timed up and go (TUG) na avaliação da aptidão cardiorrespiratória em cardiopatas não está bem definida na literatura. Objetivos Testar a associação entre o TUG e o consumo de oxigênio de pico (VO2pico), construir uma equação com base no TUG para prever o VO2pico e determinar um ponto de corte para estimar um VO2pico ≥ 20 mL.kg−1.min−1. Métodos Estudo transversal com 201 indivíduos portadores de doença arterial coronariana ou insuficiência cardíaca, com idade entre 36 e 92 anos, submetidos ao TUG e ao teste cardiopulmonar de exercício. Foram realizadas análises de correlação, curva ROC, regressão linear múltipla e Bland-Altman. Um p < 0,05 foi adotado como significante. Resultados A média de idade da amostra total foi 67 ± 13 anos, e 70% dos participantes eram do sexo masculino. A média de VO2pico foi de 17 ± 6 mL.kg−1.min−1 e a média de desempenho no TUG foi de 7 ± 2,5 segundos. A correlação entre o VO2pico e o TUG foi r = −0,54 (p < 0,001) e R2 de 0,30. Foi desenvolvida a equação com base no TUG: V O 2 pico = 33 , 553 + ( − 0 , 149 ∗ idade ) + ( − 0 , 738 ∗ T U G ) + ( − 2 , 870 ∗ sexo ); sendo atribuído o valor 0 ao sexo masculino e 1 ao sexo feminino (R ajustado: 0,41; R2 ajustado: 0,40). O VO2pico estimado pela equação foi 18,81 ± 3,2 mL.kg−1.min−1 e o determinado pelo teste cardiopulmonar de exercício foi 18,18 ± 5,9 mL.kg−1.min−1 (p > 0,05). O melhor ponto de corte para o VO2pico ≥ 20 mL.kg−1.min−1 foi de ≤ 5,47 segundos (área sob a curva: 0,80; intervalo de confiança de 95%: 0,74 a 0,86). Conclusões O TUG e o VO2pico apresentaram associação significativa. A equação preditiva do VO2pico foi desenvolvida e validada internamente com bom desempenho. O ponto de corte no TUG para prever um VO2pico ≥ 20 mL.kg−1.min−1 foi ≤ 5,47 segundos.


Abstract Background The use of the timed up and go (TUG) test to assess cardiorespiratory fitness in patients with heart disease has not been well defined in the literature. Objectives Test the association between TUG and peak oxygen consumption (VO2peak), construct an equation based on TUG to predict VO2peak, and determine a cutoff point to estimate VO2peak ≥ 20 mL/kg/min. Methods This cross-sectional study included 201 patients with coronary artery disease or heart failure, between 36 and 92 years of age, who underwent TUG and cardiopulmonary exercise test. Correlation, ROC curve, multiple linear regression, and Bland-Altman analyses were performed. The significance level was set at p < 0.05. Results The mean age of the total sample was 67 ± 13 years, and 70% of participants were male. The mean VO2peak was 17 ± 6 mL/kg/min, and the mean TUG time was 7 ± 2.5 seconds. The correlation between VO2peak and TUG was r = −0.54 (p < 0.001), and R2 was 0.30. The following equation was developed based on TUG: V O 2 peak = 33.553 + ( − 0.149 × age ) + ( − 0.738 × TUG ) + ( − 2.870 × sex ); a value of 0 was assigned to the male sex and 1 to the female sex (adjusted R: 0.41; adjusted R2: 0.40). The VO2peak estimated by the equation was 18.81 ± 3.2 mL/kg/min, and the VO2peak determined by cardiopulmonary exercise test was 18.18 ± 5.9 mL/kg/min (p > 0.05). The best cutoff point in the TUG for VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds (area under the curve: 0.80; 95% confidence interval: 0.74 to 0.86). Conclusions TUG and VO2peak showed a significant association. A prediction equation for VO2peak was developed and validated internally with good performance. The cutoff point in the TUG to predict VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds.

9.
Arq Bras Cardiol ; 120(12): e20230338, 2023 Dec.
Artigo em Português, Inglês | MEDLINE | ID: mdl-38126569

RESUMO

BACKGROUND: Central Illustration : Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test CPET: cardiopulmonary exercise test; TUG: timed up and go test; VO2peak: peak oxygen consumption. BACKGROUND: The use of the timed up and go (TUG) test to assess cardiorespiratory fitness in patients with heart disease has not been well defined in the literature. OBJECTIVES: Test the association between TUG and peak oxygen consumption (VO2peak), construct an equation based on TUG to predict VO2peak, and determine a cutoff point to estimate VO2peak ≥ 20 mL/kg/min. METHODS: This cross-sectional study included 201 patients with coronary artery disease or heart failure, between 36 and 92 years of age, who underwent TUG and cardiopulmonary exercise test. Correlation, ROC curve, multiple linear regression, and Bland-Altman analyses were performed. The significance level was set at p < 0.05. RESULTS: The mean age of the total sample was 67 ± 13 years, and 70% of participants were male. The mean VO2peak was 17 ± 6 mL/kg/min, and the mean TUG time was 7 ± 2.5 seconds. The correlation between VO2peak and TUG was r = -0.54 (p < 0.001), and R2 was 0.30. The following equation was developed based on TUG: V O 2 peak = 33.553 + ( - 0.149 × age ) + ( - 0.738 × TUG ) + ( - 2.870 × sex ) ; a value of 0 was assigned to the male sex and 1 to the female sex (adjusted R: 0.41; adjusted R2: 0.40). The VO2peak estimated by the equation was 18.81 ± 3.2 mL/kg/min, and the VO2peak determined by cardiopulmonary exercise test was 18.18 ± 5.9 mL/kg/min (p > 0.05). The best cutoff point in the TUG for VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds (area under the curve: 0.80; 95% confidence interval: 0.74 to 0.86). CONCLUSIONS: TUG and VO2peak showed a significant association. A prediction equation for VO2peak was developed and validated internally with good performance. The cutoff point in the TUG to predict VO2peak ≥ 20 mL/kg/min was ≤ 5.47 seconds.


Assuntos
Insuficiência Cardíaca , Equilíbrio Postural , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Estudos de Tempo e Movimento , Teste de Esforço , Consumo de Oxigênio
10.
Polymers (Basel) ; 15(21)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37959981

RESUMO

Electrospun nanofibrous membranes have garnered significant attention in antimicrobial applications, owing to their intricate three-dimensional network that confers an interconnected porous structure, high specific surface area, and tunable physicochemical properties, as well as their notable capacity for loading and sustained release of antimicrobial agents. Tailoring polymer or hybrid-based nanofibrous membranes with stimuli-responsive characteristics further enhances their versatility, enabling them to exhibit broad-spectrum or specific activity against diverse microorganisms. In this review, we elucidate the pivotal advancements achieved in the realm of stimuli-responsive antimicrobial electrospun nanofibers operating by light, temperature, pH, humidity, and electric field, among others. We provide a concise introduction to the strategies employed to design smart electrospun nanofibers with antimicrobial properties. The core section of our review spotlights recent progress in electrospun nanofiber-based systems triggered by single- and multi-stimuli. Within each stimulus category, we explore recent examples of nanofibers based on different polymers and antimicrobial agents. Finally, we delve into the constraints and future directions of stimuli-responsive nanofibrous materials, paving the way for their wider application spectrum and catalyzing progress toward industrial utilization.

11.
Chem Biodivers ; 20(11): e202300931, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37776535

RESUMO

Bacteria are associated with many infections that affect humans and present antibiotic resistance mechanisms, causing problems in health organisations and increased mortality rates. Therefore, it is necessary to find new antibacterial agents that can be used in the treatment of these microorganisms. Geopropolis is a natural product from stingless bees, formed by a mixture of plant resins, salivary secretions, wax and soil particles, the chemical composition of this natural product is diverse. Thus, this study aimed to evaluate antibacterial activity, antibiotic modulation and the toxicity of geopropolis extracts from the stingless bees, Melipona subnitida (Ducke, 1910) and Scaptotrigona depilis (Moure, 1942) against standard and multi-resistant Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa bacteria. Geopropolis samples were collected in a meliponary located in Camaragibe, Pernambuco, Brazil. To determine the Minimum Inhibitory Concentration (MIC) and antibiotic modulation we performed broth microdilution tests. Mortality tests were used to verify extract toxicity in the model Drosophila melanogaster. The microbiological tests showing that the M. subnitida extracts had better inhibitory effects compared to S. depilis, presenting direct antibacterial activity against standard and multi-resistant strains. The extracts potentialized antibiotic effects, suggesting possible synergy and did not present toxicity in the model used. The information obtained in this study highlights extracts as promising antibacterial agents and is the first study to evaluate bacterial activity in these extracts, in addition to verifying their modulating effects and determining toxicity in the model used.


Assuntos
Himenópteros , Staphylococcus aureus Resistente à Meticilina , Própole , Abelhas , Humanos , Animais , Drosophila melanogaster , Própole/química , Antibacterianos/farmacologia , Pseudomonas , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia
12.
Int J Biol Macromol ; 251: 126314, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37586628

RESUMO

Nanomaterial-based wound dressings have been extensively studied for the treatment of both minor and life-threatening tissue injuries. These wound dressings must possess several crucial characteristics, such as tissue compatibility, non-toxicity, appropriate biodegradability to facilitate wound healing, effective antibacterial activity to prevent infection, and adequate physical and mechanical strength to withstand repetitive dynamic forces that could potentially disrupt the healing process. Nevertheless, the development of nanostructured wound dressings that incorporate various functional micro- and nanomaterials in distinct architectures, each serving specific purposes, presents significant challenges. In this study, we successfully developed a novel multifunctional wound dressing based on poly(lactic acid) (PLA) fibrous membranes produced by solution-blow spinning (SBS) and electrospinning. The PLA-based membranes underwent surface modifications aimed at tailoring their properties for utilization as effective wound dressing platforms. Initially, beta-chitin whiskers were deposited onto the membrane surface through filtration, imparting hydrophilic character. Afterward, silver nanoparticles (AgNPs) were incorporated onto the beta-chitin layer using a spray deposition method, resulting in platforms with antimicrobial properties against both Staphylococcus aureus and Escherichia coli. Cytotoxicity studies demonstrated the biocompatibility of the membranes with the neonatal human dermal fibroblast (HDFn) cell line. Moreover, bilayer membranes exhibited a high surface area and porosity (> 80%), remarkable stability in aqueous media, and favorable mechanical properties, making them promising candidates for application as multifunctional wound dressings.

13.
Sci Total Environ ; 900: 166315, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37604376

RESUMO

The indiscriminate use of pesticides represents high ecological risk in aquatic systems. Recently, the inclusion of epilithic biofilms as a reactive matrix has shown potential in diagnosing the health of water resources. The objective of this study was to use multiple matrices (water, suspended sediments, and biofilms) to discriminate contamination degrees in catchments with long and recent history of intensive pesticide use and to monitor growing season pesticides transfer to watercourses. Two catchments were monitored: one representative of "modern agriculture" in a subtropical environment, and another representative of recent agricultural expansion over the Pampa Biome in subtropical Brazil. Glyphosate and AMPA were accumulated in the biofilms and were detected at all sites and at all monitoring times, in concentrations ranging from 195 to 7673 µg kg-1 and from 225 to 4180 µg kg-1, respectively. Similarly, the fungicide tebuconazole has always been found in biofilms. The biofilms made it possible to discriminate the long-term history of pesticide use in the catchments and even to identify the influx pulses of pesticides immediately after their application to crops, which was not possible with active water sampling and even with suspended sediment monitoring. It is strongly recommended that, in regions with intensive cultivation of soybeans and other genetically modified crops, the presence of glyphosate and its metabolite AMPA be permanently monitored, a practice still very scarce in the literature.


Assuntos
Praguicidas , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico , Produtos Agrícolas , Estações do Ano , Plantas Geneticamente Modificadas , Biofilmes , Água , Glifosato
14.
Toxics ; 11(8)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37624194

RESUMO

Eutrophication in water reservoirs releases algal organic matter (AOM), which is an important precursor of disinfection by-products (DBPs) formed during water treatment. Chlorella sorokiniana is a microalgae which flourishes under conditions of high light intensity and temperature, thus its prevalence in algal blooms is expected to increase with climate change. However, Chlorella sorokiniana AOM has not been previously investigated as a DBP precursor. In this context, this study evaluated the effect of AOM concentration, humic acid (HA), and pH on DBP formation from chlor(am)ination of AOM Chlorella sorokiniana. DBP yields determined by linear regression for trichloromethane (TCM) and chloral hydrate (CH) were 57.9 and 46.0 µg·mg DOC-1 in chlorination, while the TCM, CH, dichloroacetonitrile (DCAN), 1,1,1-trichloropropanone (1,1,1-TCP), and chloropicrin (CPN) concentrations were 33.6, 29.8, 16.7, 2.1, and 1.2 µg·mg DOC-1 in chloramination. Chloramination reduced the formation of TCM and CH but increased CPN, DCAN, and 1,1,1-TCP yields. AOM Chlorella sorokiniana showed a higher DBP formation than 9 of 11 algae species previously investigated in the literature. At basic pH, the concentration of TCM increased while the concentration of other DBP classes decreased. Bromide was effectively incorporated into the AOM structure and high values of bromine incorporation factor were found for THM (1.81-1.89) and HAN (1.32) at 1.5 mg Br·L-1. Empirical models predicted successfully the formation of THM and HAN (R2 > 0.86). The bromide concentration had more impact in the model on the DBP formation than AOM and HA. These results provide the first insights into the DBP formation from AOM chlor(am)ination of Chlorella sorokiniana.

15.
Sensors (Basel) ; 23(14)2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37514581

RESUMO

Federated learning (FL) is a distributed training method for machine learning models (ML) that maintain data ownership on users. However, this distributed training approach can lead to variations in efficiency due to user behaviors or characteristics. For instance, mobility can hinder training by causing a client dropout when a device loses connection with other devices on the network. To address this issue, we propose a FL coordination algorithm, MoFeL, to ensure efficient training even in scenarios with mobility. Furthermore, MoFeL evaluates multiple networks with different central servers. To evaluate its effectiveness, we conducted simulation experiments using an image classification application that utilizes machine models trained by a convolutional neural network. The simulation results demonstrate that MoFeL outperforms traditional training coordination algorithms in FL, with 156.5% more training cycles, in scenarios with high mobility compared to an algorithm that does not consider mobility aspects.

16.
Front Sports Act Living ; 5: 1216002, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440874

RESUMO

Introduction: The International Judo Federation introduced a ranking system in 2009 that determines top athletes for the Olympic Games and seeds them in competitions. Previous research indicated that this ranking list and past performances predicted 19%-27% of performance in the Olympic Games and World Championships. However, due to the COVID-19 pandemic, the relationship between Judo World Tour competitions and Olympic Games performance may have been affected. This study aimed to examine the relationship between athletes' performance in Judo World Tour competitions and their competitive performance at the Olympic Games. Methods: Data from 393 athletes who participated in the Tokyo Olympics were analyzed considering both long and short-term performance measures. Pearson correlation was used to determine the relationship between variables and multiple linear regressions were used to predict performance for each sex and the entire sample. Results: The results revealed a range of magnitudes in the correlation between variables, varying from small to large. In terms of regression analyses, it was observed that, for females, the percentage of matches won during the classification period and competition in the year prior to the Olympic Games predicted 37% of their performance. For males, the percentage of matches won during the classification period and competition in the six months before the Olympic Games predicted 36% of their performance. Discussion: Thus, athletes' quality and reduced exposure to competition near the Olympic Games appear to be important factors in their performance at the event.

17.
Environ Res ; 233: 116443, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356524

RESUMO

Among the ESKAPE group pathogens, Enterobacter spp. is an opportunistic Gram-negative bacillus, widely dispersed in the environment, that causes infections. In the present study, samples of hospital wastewater, raw and treated urban wastewater, as well as surface receiving water, were collected to assess the occurrence of multidrug-resistant (MDR) Enterobacter spp. A molecular characterization of ß-lactam antibiotic resistance and metal tolerance genes was performed. According to identification by MALDI-TOF MS, 14 isolates were obtained: 7 E. bugandensis, 5 E. kobei, and 2 E. cloacae. The isolates showed resistance mainly to ß-lactam antibiotics, including those used to treat infections caused by MDR bacteria. Multiple antibiotic resistance index was calculated for all isolates. It allowed verify whether sampling points showed a high risk due to antibiotic resistant Enterobacter spp., as well as to determine if the isolates have been in environments with a frequent antibiotic use. Twelve isolates showed ß-lactam antibiotic resistance gene, being the blaKPC widely detected. Regarding metal tolerance, 13 isolates showed at least two genes that encode metal tolerance mechanisms. Overall, metal tolerance mechanisms to silver, copper, mercury, arsenic and tellurium were found. New data on metal tolerance mechanisms dispersion and antibiotic-resistance characterization of the E. bugandensis and E. kobei species were here provided. The occurrence of MDR Enterobacter spp. in analyzed samples draws attention to an urgent need to put control measures into practice. It also evidences waterborne spread of clinically important antibiotic-resistant bacteria recognized as critical priority pathogens.


Assuntos
Enterobacter , Águas Residuárias , Enterobacter/genética , Resistência beta-Lactâmica , Antibacterianos/farmacologia , beta-Lactamas/farmacologia , beta-Lactamases/genética , Testes de Sensibilidade Microbiana
18.
ACS Omega ; 8(15): 13721-13732, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37091421

RESUMO

We report a nanoarchitectonic electronic tongue made with flexible electrodes coated with curcumin carbon dots and zein electrospun nanofibers, which could detect Staphylococcus aureus(S. aureus) in milk using electrical impedance spectroscopy. Electronic tongues are based on the global selectivity concept in which the electrical responses of distinct sensing units are combined to provide a unique pattern, which in this case allowed the detection of S. aureus through non-specific interactions. The electronic tongue used here comprised 3 sensors with electrodes coated with zein nanofibers, carbon dots, and carbon dots with zein nanofibers. The capacitance data obtained with the three sensors were processed with a multidimensional projection technique referred to as interactive document mapping (IDMAP) and analyzed using the machine learning-based concept of multidimensional calibration space (MCS). The concentration of S. aureus could be determined with the sensing units, especially with the one containing zein as the limit of detection was 0.83 CFU/mL (CFU stands for colony-forming unit). This high sensitivity is attributed to molecular-level interactions between the protein zein and C-H groups in S. aureus according to polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS) data. Using machine learning and IDMAP, we demonstrated the selectivity of the electronic tongue in distinguishing milk samples from mastitis-infected cows from milk collected from healthy cows, and from milk spiked with possible interferents. Calibration of the electronic tongue can also be reached with the MCS concept employing decision tree algorithms, with an 80.1% accuracy in the diagnosis of mastitis. The low-cost electronic tongue presented here may be exploited in diagnosing mastitis at early stages, with tests performed in the farms without requiring specialized laboratories or personnel.

19.
J Environ Sci Health B ; 58(3): 273-284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36861268

RESUMO

Spatial-temporal monitoring of the presence of pesticides and pharmaceuticals in water requires rigor in the choice of matrix to be analyzed. The use of matrices, isolated or combined, may better represent the real state of contamination. In this sense, the present work contrasted the effectiveness of using epilithic biofilms with active water sampling and with a passive sampler-POCIS. A watershed representative of South American agriculture was monitored. Nine sites with different rural anthropic pressures (natural forest, intensive use of pesticides, and animal waste), and urban areas without sewage treatment, were monitored. Water and epilithic biofilms were collected during periods of intensive pesticide and animal waste application. After the harvest of the spring/summer crop, a period of low agrochemical input, the presence of pesticides and pharmaceuticals was monitored using the POCIS and epilithic biofilms. The spot water sampling leads to underestimation of the level of contamination of water resources as it does not allow discrimination of different anthropic pressures in rural areas. The use of endogenous epilithic biofilms as a matrix for the analysis of pesticides and pharmaceuticals is a viable and highly recommended alternative to diagnose the health of water sources, especially if associated with the use of POCIS.


Assuntos
Praguicidas , Poluentes Químicos da Água , Praguicidas/análise , Brasil , Fonte de Informação , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Biofilmes , Preparações Farmacêuticas , Rios
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