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1.
Foods ; 13(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38790742

RESUMO

The objective of this work was to gain insight into the operating conditions that affect the efficiency of ultrasound-assisted extraction (UAE) parameters to achieve the best recovery of bioactive compounds from broccoli leaf and floret byproducts. Therefore, total phenolic content (TPC) and the main sulfur bioactive compounds (sulforaphane (SFN) and glucosinolates (GLSs)) were assayed. Distilled water was used as solvent. For each byproduct type, solid/liquid ratio (1:25 and 2:25 g/mL), temperature (25, 40, and 55 °C), and extraction time (2.5, 5, 7.5, 10, 15, and 20 min) were the studied variables to optimize the UAE process by using a kinetic and a cubic regression model. TPC was 12.5-fold higher in broccoli leaves than in florets, while SFN was from 2.5- to 4.5-fold higher in florets regarding the leaf's extracts obtained from the same plants, their precursors (GLS) being in similar amounts for both plant tissues. The most efficient extraction conditions were at 25 °C, ratio 2:25, and during 15 or 20 min according to the target phytochemical to extract. In conclusion, the type of plant tissue and used ratio significantly influenced the extraction of bioactive compounds, the most efficient UAE parameters being those with lower energy consumption.

2.
Foods ; 12(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38137260

RESUMO

Response Surface Methodology (RSM) is a widely used mathematical tool for process optimization, setting their main factorial variables. The current research analyzes and summarizes the current knowledge about the RSM in the extraction of carotenoids from fruit and vegetable by-products, following a systematic review protocol (Prisma 2020 Statement). After an identification of manuscripts in Web of Science (September 2023) using inclusion search terms ("carotenoids", "extraction", "response-surface methodology", "ultrasound", "microwave" and "enzyme"), they were screened by titles and abstracts. Finally, 29 manuscripts were selected according to the PRISMA methodology (an evidence-based minimum set of items for reporting in systematic reviews), then, 16 questions related to the quality criteria developed by authors were applied. All studies were classified as having an acceptable level of quality criteria (≤50% "yes answers"), with four of them reaching a moderate level (>50 to ≤70% "yes answers"). No studies were cataloged as complete (>70% "yes answers"). Most studies are mainly focused on ultrasound-assisted extraction, which has been widely developed compared to microwave or enzymatic-assisted extractions. Most evidence shows that it is important to provide information when RSM is applied, such as the rationale for selecting a particular design, the specification of input variables and their potential levels, a discussion on the statistical model's validity, and an explanation of the optimization procedure. In addition, the principles of open science, specifically data availability, should be included in future scientific manuscripts related to RSM and revalorization.

3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(4 Pt 1): 041114, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23214536

RESUMO

Excitability is observed in a variety of natural systems, such as neuronal dynamics, cardiovascular tissues, or climate dynamics. The stochastic FitzHugh-Nagumo model is a prominent example representing an excitable system. To validate the practical use of a model, the first step is to estimate model parameters from experimental data. This is not an easy task because of the inherent nonlinearity necessary to produce the excitable dynamics, and because the two coordinates of the model are moving on different time scales. Here we propose a Bayesian framework for parameter estimation, which can handle multidimensional nonlinear diffusions with large time scale separation. The estimation method is illustrated on simulated data.


Assuntos
Biofísica/métodos , Algoritmos , Teorema de Bayes , Simulação por Computador , Difusão , Cadeias de Markov , Método de Monte Carlo , Dinâmica não Linear , Distribuição Normal , Oscilometria/métodos , Processos Estocásticos
4.
Acad Emerg Med ; 16(12): 1374-1377, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20053262

RESUMO

OBJECTIVE: The objective was to establish the feasibility of using an automated external chest compression (ECC) device among first-aid workers unfamiliar with the device. METHODS: Eighty first-aid workers unfamiliar with the Autopulse ECC device were randomized into three groups. Group 1 was given two explanatory illustrations on device use. Group 2 was given four explanatory illustrations. Group 3 was shown a 5-minute video on the placement and use of the device and allowed to handle the device for 5 minutes. The time taken to place and start the device on a mannequin was recorded. RESULTS: There was no significant difference among the three groups with regard to age, sex ratio, experience, and time elapsed since their last training session. No mistakes in device placement were made by any of the groups. All 80 participants started ECC in less than 160 seconds. There was no significant difference between Groups 1 and 2 in time taken to place or start the device (medians and 25-75 percentiles = 72 [54-112] vs. 86 [46-130] seconds and 154 [103-183] vs. 156 [120-197] seconds, respectively). However, Group 3 first-aid workers obtained significantly better results (19 [16-26] seconds to place and 48 [40-65] seconds to start; p<0.0001). CONCLUSIONS: An automated ECC device can be rapidly placed and used by first-aid workers unfamiliar with the device. In the light of these results, use of the device by the general public can be envisaged.


Assuntos
Primeiros Socorros/instrumentação , Conhecimentos, Atitudes e Prática em Saúde , Parada Cardíaca/terapia , Massagem Cardíaca/instrumentação , Adulto , Feminino , Primeiros Socorros/métodos , Massagem Cardíaca/métodos , Humanos , Masculino , Manequins , Estudos Prospectivos , Resultado do Tratamento
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