Search results for "Extraction"
showing 10 items of 2072 documents
Application of pressurized fluid extraction to determine cadmium and zinc in plants
2006
Abstract A procedure for the determination of Cd and Zn in plants is proposed. The metals are extracted by pressurized fluid extraction (PFE). Operational conditions are: pressure 1500 psi, temperature 75 °C, static time 5 min, flush volume 35%, purge time 60 s, cycles 1 and 1,2-diaminocyclohexane- N , N , N ′, N ′-tetraacetic acid (CDTA) 0.01 M at pH 4.5 as extracting solution. Determination of Zn is carried out by flame atomic absorption spectroscopy and depending on the concentration level, Cd content is determined by flame or electrothermal atomic absorption spectroscopy. Certified samples of Virginia tobacco leaves, tea leaves, spinach leaves, poplar leaves, a commercial spinach sample…
Aprendizaje de similitudes entre pares de objetos mediante clasificación supervisada
2017
El uso de medidas de similitud, distancias o métricas se encuentra en la base del funcionamiento de numerosas técnicas estándar de clasificación, resultando además, una tarea fundamental e importante en las áreas de estudio del Aprendizaje Automático (Machine Learning) y el Reconocimiento de Patrones (Pattern Recognition). Dado que el cálculo de la similitud entre dos objetos puede ser muy diferente en función del contexto, la construcción inteligente de estas medidas a partir de los datos disponibles, puede ayudar en la obtención de clasificadores más robustos y mejorar los resultados en la tarea específica que se propone resolver. En los últimos años, el aprendizaje de métricas (Metric Le…
Third molar surgical difficulty scales: systematic review and preoperative assessment form
2021
Background The main objective of this systematic review was to collect the pre-existing scales for assessing the difficulty of third molar extraction. The secondary objective was to design a proposal for a preoperative evaluation protocol for the difficulty of third molar extraction. Material and Methods Two independent researchers conducted an electronic search in Pubmed (MEDLINE), Cochrane, and Scopus databases during March 2021. Included studies evaluated the prediction of the difficulty of surgical removal of impacted upper or lower third molars using new indices/scales or pre-existing scales with or without modifications. Articles referring to coronectomies or assessing pre-surgical di…
Polyamines : études et applications
2008
International audience
Morbidity of third molar extraction in patients between 12 and 18 years of age
2005
Objetivo: El propósito de este estudio fue analizar la incidencia de complicaciones después de la extracción quirúrgica de los terceros molares en pacientes de 12 a 18 años de edad. Pacientes y método: Se realizó un estudio retrospectivo de 390 extracciones quirúgicas de terceros molares superiores e inferiores en 173 pacientes en edades comprendidas entre los 12 y 18 años de edad, intervenidos bajo anestesia locorregional en el año 2000 en el Máster de Cirugía Bucal e Implantología Bucofacial de la Universidad de Barcelona. Los pacientes fueron divididos en tres grupos (A: 12-14 años, B:15-16 años, C: 17-18 años). Se registró la edad y el sexo del paciente, el motivo de la extracción, el g…
Corylus avellana: A Source of Diarylheptanoids With α-Glucosidase Inhibitory Activity Evaluated by in vitro and in silico Studies
2022
Corylus avellana hard shells, green leafy involucres, leaves, and male flowers have shown to be a source of diarylheptanoids, a class of natural products with promising biological activities. Cyclic diarylheptanoids, named giffonins, were isolated from the Italian cultivar “Tonda di Giffoni.” Even if many efforts have been made to establish the chemistry of these compounds, little is known about their biological properties. Herein, the inhibitory effects of diarylheptanoids isolated from C. avellana byproducts against α-glucosidase enzyme were evaluated. Molecular docking experiments disclosed the establishment of several key interactions between all the screened diarylheptanoids and the pr…
Linear Feature Extraction for Ranking
2018
We address the feature extraction problem for document ranking in information retrieval. We then propose LifeRank, a Linear feature extraction algorithm for Ranking. In LifeRank, we regard each document collection for ranking as a matrix, referred to as the original matrix. We try to optimize a transformation matrix, so that a new matrix (dataset) can be generated as the product of the original matrix and a transformation matrix. The transformation matrix projects high-dimensional document vectors into lower dimensions. Theoretically, there could be very large transformation matrices, each leading to a new generated matrix. In LifeRank, we produce a transformation matrix so that the generat…
Extracting (good) discourse examples from an oral specialised corpus of wine tasting interactions
2015
International audience; This article outlines the semi-automated extraction of dictionary examples used in the compilation of a professional online dictionary of wine tasting. Named OenoLex Bourgogne, this dictionary was started to respond to the demand for a lexicographic information tool from the French wine industry of Burgundy, the Bureau Interprofessionnel des Vins de Bourgogne.
Dynamics and extraction of quantum discord in a multipartite open system
2011
We consider a multipartite system consisting of two noninteracting qubits each embedded in a single-mode leaky cavity, in turn connected to an external bosonic reservoir. Initially, we take the two qubits in an entangled state while the cavities and the reservoirs have zero photons. We investigate, in this six-partite quantum system, the transfer of quantum discord from the qubits to the cavities and reservoirs. We show that this transfer occurs also when the cavities are not entangled. Moreover, we discuss how quantum discord can be extracted from the cavities and transferred to distant systems by traveling leaking photons, using the input-output theory.
Cobalt content of foods and diets in a Spanish population
1986
The WHO Expert Committee on Food Contaminants has pointed out the need of determining the content of foods in trace elements in order to ascertain their contribution to the total intake of oligoelements through the diet. Since the contents in trace elements depend on the environmental features, it is necessary to carry out systematic determinations of trace elements in foods of local origin in order to know the exposure level of population. This work intends to study the cobalt contribution through the diet. The element intake is calculated from the cobalt content in raw foods after elimination of the non-eatable moiety by flame atomic absorption spectroscopy, after formation of a chelate w…