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1.
Foods ; 9(9)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882806

RESUMO

An untargeted method using direct analysis in real time and high resolution mass spectrometry (DART-HRMS) combined to multivariate statistical analysis was developed for the discrimination of two monofloral (chestnut and acacia) honeys for their geographical origins-i.e., Italy and Portugal for chestnut honey and Italy and China for acacia honey. Principal Component Analysis, used as an unsupervised approach, showed samples of clusterization for chestnut honey samples, while overlapping regions were observed for acacia honeys. Three supervised statistical approaches, such as Principal Components-Linear Discriminant Analysis, Partial Least Squares-Discriminant Analysis and k-nearest neighbors, were tested on the dataset gathered and relevant performances were compared. All tested statistical approaches provided comparable prediction abilities in cross-validation and external validation with mean values falling between 89.2-98.4% for chestnut and between 85.8-95.0% for acacia honey. The results obtained herein indicate the feasibility of the DART-HRMS approach in combination with chemometrics for the rapid authentication of honey's geographical origin.

2.
J Sci Food Agric ; 98(13): 4955-4962, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29577312

RESUMO

BACKGROUND: Deoxynivalenol (DON) is a mycotoxin, mainly produced by Fusarium sp., most frequently occurring in cereals and cereal-based products. Wheat bran refers to the outer layers of the kernel, which has a high risk of damage due to chemical hazards, including mycotoxins. Rapid methods for DON detection in wheat bran are required. RESULTS: A rapid screening method using an electronic nose (e-nose), based on metal oxide semiconductor sensors, has been developed to distinguish wheat bran samples with different levels of DON contamination. A total of 470 naturally contaminated wheat bran samples were analyzed by e-nose analysis. Wheat bran samples were divided in two contamination classes: class A ([DON] ≤ 400 µg kg-1 , 225 samples) and class B ([DON] > 400 µg kg-1 , 245 samples). Discriminant function analysis (DFA) classified wheat bran samples with good mean recognizability in terms of both calibration (92%) and validation (89%). A pattern of 17 volatile compounds of wheat bran samples that were associated (positively or negatively) with DON content was also characterized by HS-SPME/GC-MS. CONCLUSIONS: These results indicate that the e-nose method could be a useful tool for high-throughput screening of DON-contaminated wheat bran samples for their classification as acceptable / rejectable at contamination levels close to the EU maximum limit for DON, reducing the number of samples to be analyzed with a confirmatory method. © 2018 Society of Chemical Industry.


Assuntos
Fibras na Dieta/análise , Nariz Eletrônico/estatística & dados numéricos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Micotoxinas/análise , Tricotecenos/análise , Compostos Orgânicos Voláteis/análise , Análise de Alimentos/instrumentação , Cromatografia Gasosa-Espectrometria de Massas
3.
Food Chem ; 237: 743-748, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28764061

RESUMO

Lentil samples coming from two different countries, i.e. Italy and Canada, were analysed using untargeted 1H NMR fingerprinting in combination with chemometrics in order to build models able to classify them according to their geographical origin. For such aim, Soft Independent Modelling of Class Analogy (SIMCA), k-Nearest Neighbor (k-NN), Principal Component Analysis followed by Linear Discriminant Analysis (PCA-LDA) and Partial Least Squares-Discriminant Analysis (PLS-DA) were applied to the NMR data and the results were compared. The best combination of average recognition (100%) and cross-validation prediction abilities (96.7%) was obtained for the PCA-LDA. All the statistical models were validated both by using a test set and by carrying out a Monte Carlo Cross Validation: the obtained performances were found to be satisfying for all the models, with prediction abilities higher than 95% demonstrating the suitability of the developed methods. Finally, the metabolites that mostly contributed to the lentil discrimination were indicated.


Assuntos
Lens (Planta) , Análise Discriminante , Espectroscopia de Ressonância Magnética , Análise Multivariada
4.
Int Orthop ; 34(8): 1115-21, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19763569

RESUMO

The aim of this study was to evaluate the effects of limb lengthening up to 20 mm after THA on symmetry of hip kinematics and kinetics during common activities of daily living. Twenty patients (age range 49-80 years) operated on with Link Lubinus II THA, with lateral access and a mean follow-up of 16 months, were assessed by gait analysis during level walking, stair ascending and descending. The time-distance, hip kinetics and kinematics values were statistically compared between the operated side and the non-operated side in order to assess symmetry. The 12-item Questionnaire was used to assess satisfaction and personal perception of limb lengthening. Mean value of limb lengthening after THA was 11 mm (SD 6). Minor abnormalities were found in the kinematics and kinetics of the operated and non-operated hips during level walking and stair climbing. The score of the questionnaire corresponded to a high level of satisfaction after THA and only two patients complained of limping independent from the amount of discrepancy. From this study we can conclude that a leg length inequality in the range of 1-20 mm does not impair the symmetry of time-distance parameters and of hip kinematics and kinetics during gait and stairs walking. Although objective, gait analysis data did not correspond to patient's perception of discrepancy, which is subjective and irrespective of the amount of lengthening. There is biomechanical evidence that a limb lengthening of up to two centimetres after THA in general does not need to be corrected by means of a contralateral shoe lift. Individual decisions to the contrary need to be justified.


Assuntos
Artroplastia de Quadril/efeitos adversos , Marcha/fisiologia , Articulação do Quadril/cirurgia , Desigualdade de Membros Inferiores/etiologia , Atividade Motora/fisiologia , Complicações Pós-Operatórias , Idoso , Idoso de 80 Anos ou mais , Feminino , Articulação do Quadril/fisiopatologia , Humanos , Desigualdade de Membros Inferiores/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica
5.
J Neuroeng Rehabil ; 6: 47, 2009 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-20040120

RESUMO

BACKGROUND: Obesity is a major problem especially in western countries and several studies underline the importance of physical activity to enhance diet. Currently there is increasing interest in instruments for monitoring daily physical activity. The purpose of this pilot study was to appraise the qualitative and quantitative differences in physical activities and gait analysis parameters in control and obese subjects by means of an innovative tool for the monitoring of physical activity. METHODS: Twenty-six obese patients, 16 women and 10 men, aged 22 to 69 years with Body Mass Index (BMI) between 30 and 51.4 kg/m2, were compared with 15 control subjects, 4 men and 11 women, aged 24 to 69 with BMI between 18 and 25 kg/m2 during daily physical activities. The IDEEA device (Minisun, Fresno, CA), based on a wearable system of biaxial accelerometers and able to continuously record the physical activities and energy expenditure of a subject in time was used. Time spent in different physical activities such as standing, sitting, walking, lying, reclining, stepping, energy expenditure and gait parameters (velocity, stance duration, etc) were measured during a 24-hours period. RESULTS: A trend toward a reduced number of steps was present, associated to reduced speed, reduced cadence and reduced rate of single and double limb support (SLS/DLS). Moreover, obese people spent significant less time stepping, less time lying and more time in a sitting or reclined position during the night. The energy expenditure during a 24-hours period was higher in the obese compared to controls. CONCLUSIONS: The study provided objective parameters to differentiate the daily motor activity of obese subjects with respect to controls, even a larger population is required to confirm these findings. The device used can be of support in programming educational activities for life style modification in obese people as well as for monitoring the results of various kinds of intervention in these patients concerning weight and physical performance.


Assuntos
Meio Ambiente , Monitorização Ambulatorial/métodos , Atividade Motora , Obesidade , Adulto , Idoso , Índice de Massa Corporal , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
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