Search results for "validation"
showing 10 items of 620 documents
Sexing birds using discriminant function analysis: a critical appraisal.
2011
9 pages; International audience; Discriminant function analysis (DFA) based on morphological measurements is a quick, inexpensive, and efficient method for sex determination in field studies on cryptically monomorphic bird species. However, behind the apparent standardization and relative simplicity of DFA lie subtle differences and pitfalls that have been neglected in some studies. Most of these concerns directly affect assessment of the discriminant performance, a parameter of crucial importance in practice because it provides a measure of the quality of an equation that may be used in later field studies. Using results from 141 published studies and simulations based on a large data set …
Fishery-dependent and -independent data lead to consistent estimations of essential habitats
2016
AbstractSpecies mapping is an essential tool for conservation programmes as it provides clear pictures of the distribution of marine resources. However, in fishery ecology, the amount of objective scientific information is limited and data may not always be directly comparable. Information about the distribution of marine species can be derived from two main sources: fishery-independent data (scientific surveys at sea) and fishery-dependent data (collection and sampling by observers in commercial vessels). The aim of this paper is to compare whether these two different sources produce similar, complementary, or different results. We compare them in the specific context of identifying the Es…
Dynamic Response of a Rigital Displacement Motor Operating with Various Displacement Strategies
2019
Digital displacement technology has the potential of revolutionizing the performance of hydraulic piston pumps and motors. Instead of connecting each cylinder chamber to high and low pressure in conjunction with the shaft position, two electrically-controlled on/off valves are connected to each chamber. This allows for individual cylinder chamber control. Variable displacement can be achieved by using different displacement strategies, like for example the full stroke, partial stroke, or sequential partial stroke displacement strategy. Each displacement strategy has its transient and steady-state characteristics. This paper provides a detailed simulation analysis of the transient and steady…
Adjusted bat algorithm for tuning of support vector machine parameters
2016
Support vector machines are powerful and often used technique of supervised learning applied to classification. Quality of the constructed classifier can be improved by appropriate selection of the learning parameters. These parameters are often tuned using grid search with relatively large step. This optimization process can be done computationally more efficiently and more precisely using stochastic search metaheuristics. In this paper we propose adjusted bat algorithm for support vector machines parameter optimization and show that compared to the grid search it leads to a better classifier. We tested our approach on standard set of benchmark data sets from UCI machine learning repositor…
Bidimensional Structure of the Orthorexia: Development and Initial Validation of a New Instrument
2018
La ortorexia nerviosa puede entenderse como una preocupa- ción extrema o excesiva con alimentarse de comida considerada sana. Se puede distinguir entre ortorexia nerviosa y ortorexia saludable (interés en comer sano). Hasta ahora, no hay ningún instrumento disponible para eva- luar cada aspecto de la ortorexia con suficientes garantías psicométricas. El objetivo de este estudio era doble. Primero, desarrollar y validar un nuevo cuestionario de ortorexia –la Teruel Orthorexia Scale– y, segundo, analizar la asociación con otros contructos psicológicos y trastornos teóricamente relacionados con la ortorexia nerviosa: síntomas de trastornos de la alimen- tación, síntomas de trastorno obsesivo-c…
Dry selection and wet evaluation for the rational discovery of new anthelmintics
2017
Helminths infections remain a major problem in medical and public health. In this report, atom-based 2D bilinear indices, a TOMOCOMD-CARDD (QuBiLs-MAS module) molecular descriptor family and linear discriminant analysis (LDA) were used to find models that differentiate among anthelmintic and non-anthelmintic compounds. Two classification models obtained by using non-stochastic and stochastic 2D bilinear indices, classified correctly 86.64% and 84.66%, respectively, in the training set. Equation 1(2) correctly classified 141(135) out of 165 [85.45%(81.82%)] compounds in external validation set. Another LDA models were performed in order to get the most likely mechanism of action of anthelmin…
Mass Spectrometry Imaging Differentiates Chromophobe Renal Cell Carcinoma and Renal Oncocytoma with High Accuracy
2020
Background: While subtyping of the majority of malignant chromophobe renal cell carcinoma (cRCC) and benign renal oncocytoma (rO) is possible on morphology alone, additional histochemical, immunohistochemical or molecular investigations are required in a subset of cases. As currently used histochemical and immunohistological stains as well as genetic aberrations show considerable overlap in both tumors, additional techniques are required for differential diagnostics. Mass spectrometry imaging (MSI) combining the detection of multiple peptides with information about their localization in tissue may be a suitable technology to overcome this diagnostic challenge. Patients and Methods: Formalin…
First report on the presence of Alloxan in bleached flour by LC-MS/MS method
2017
Abstract In this work the presence of Alloxan in bread, pastry and cake bleached flour was investigate in order to verify possible risk for consumers related to the use of chemicals for flour bleaching. A selective UHPLC–MS/MS method has been developed and validated for the purpose. Alloxan is one of the possible minor side products of oxidation after chemical bleaching of wheat flours, when several chemical agents are used. One hundred and seventy-five flour samples were analyzed for Alloxan determination. The validation of the method was performed in accordance with the ISO/IEC/EN 17025 for linearity, detection limit, quantification limit, accuracy, precision and ruggedness determination.…
Associations between parental food choice motives, health-promoting feeding practices, and infants' fruit and vegetable intakes: the Food4toddlers st…
2020
Background: Parents influence their infants' diets and are the providers of healthy foods such as fruit and vegetables. Parental motives can influence infant's diets directly or through parental feeding practices. Objective: This study aimed to assess the associations between parental food choice motives and infants' fruit and vegetable intakes and to examine whether parental feeding practices mediated these associations. Design: A total of 298 parents participated in the Norwegian Food4toddlers study. Before the child's first birthday (mean age = 10.9 months), the parents completed an online baseline questionnaire. Five parental food choice motives were assessed: health, convenience, senso…
Determinants of the Quality of Warfarin Control after Venous Thromboembolism and Validation of the SAMe-TT2-R2 Score: An Analysis of Hokusai-VTE.
2019
Background Time in therapeutic range (TTR) measures the quality of vitamin K antagonist (VKA) anticoagulation. In patients with atrial fibrillation, the dichotomized SAMe-TT2-R2 score (≥2 vs. < 2 points) can predict if adequate TTR is unlikely to be achieved. Aims We validated the SAMe-TT2-R2 score in patients with venous thromboembolism (VTE) randomized to the warfarin arm of the Hokusai-VTE trial. Patients and Methods A total of 3,874 patients were included in the primary analysis (day 31–180 from randomization). The efficacy and safety outcomes were symptomatic recurrent VTE and major or clinically relevant non-major bleeding. Results The rates of recurrent VTE and bleeding events we…