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11.
Iván García-Magariño Carlos Medrano Inmaculada Plaza Bárbara Oliván 《Personal and Ubiquitous Computing》2016,20(6):959-971
The detection of tremors can be crucial for the early diagnosis and proper treatment of some disorders such as Parkinson’s disease. A smartphone-based application has been developed for detecting hand tremors. This application runs in background and distinguishes hand tremors from common daily activities. This application can facilitate the continuous monitoring of patients or the early detection of this symptom. The evaluation analyzes 1770 accelerometer samples with cross-validation for assessing the ability of the system for processing unknown data, obtaining a sensitivity of 95.8 % and a specificity of 99.5 %. It also analyzes continuous data for some volunteers for several days, which corroborated its high performance. 相似文献
12.
Enrique Castillo Aida Calvio Zacarías Grande Santos Snchez‐Cambronero Inmaculada Gallego Ana Rivas Jos María Menndez 《Computer-Aided Civil and Infrastructure Engineering》2016,31(3):193-218
The article provides a new Markovian–Bayesian network model to evaluate the probability of accident associated with the circulation of trains along a given high speed or conventional railway line with special consideration to human error. This probability increases as trains pass throughout the different elements encountered along the line. A Bayesian network, made up of a sequence of several connected Bayesian subnetworks, is used. A subnetwork is associated with each element in the line that implies a concentrated risk of accident or produces a change in the driver's attention, such as signals, tunnel, or viaduct entries or exits, etc. Bayesian subnetworks are also used to reproduce segments without signals where some elements add continuous risks, such as rolling stock failures, falling materials, slope slides in cuttings and embankments, etc. All subnetworks are connected with the previous one and some of them are multi‐connected because some consequences are dependent on previous errors. Because driver's attention plays a crucial role, its degradation with driving time and the changes due to seeing light signals or receiving acoustic signals is taken into consideration. The model updates the driver's attention level and accumulates the probability of accident associated with the different elements encountered along the line. This permits us to generate a continuously increasing risk graph that includes continuous and sudden changes indicating where the main risks appear and whether or not an action must be taken by the infrastructure manager. Sensitivity analysis allows the relevant and irrelevant parameters to be identified avoiding wastes of time and money by concentrating safety improvement actions only on the relevant ones. Finally, some examples are used to illustrate the model. In particular, the case of the Orense–Santiago de Compostela line, where a terrible accident took place in 2013. 相似文献
13.
Thermochemical processing of meat and bone meal: A review 总被引:1,自引:0,他引:1
Since the Bovine Spongiform Encephalopathy crisis, meat and bone meal (MBM) have been considered animal wastes. Nowadays, these animal residues are generally burnt in cement kilns and disposed of in landfills. However, several technologies are being developed in order to achieve energy valorisation of MBM by means of combustion, pyrolysis and gasification. These thermal treatments of MBM will reduce the environmental impact of landfill and, at the same time, take advantage of the MBM heating value (13-30 MJ/kg). The main results of research into combustion, pyrolysis and gasification of MBM show that the products could be used as fertilizer (solid product) and as fuel (gas and liquid products). The present work aims at reviewing the most significant studies about energy valorisation of MBM and the potential application of the products obtained in these thermochemical processes. 相似文献
14.
Rafael Llobet Marina Pollán Joaquín Antón Josefa Miranda-García María Casals Inmaculada Martínez Francisco Ruiz-Perales Beatriz Pérez-Gómez Dolores Salas-Trejo Juan-Carlos Pérez-Cortés 《Computer methods and programs in biomedicine》2014
The task of breast density quantification is becoming increasingly relevant due to its association with breast cancer risk. In this work, a semi-automated and a fully automated tools to assess breast density from full-field digitized mammograms are presented. The first tool is based on a supervised interactive thresholding procedure for segmenting dense from fatty tissue and is used with a twofold goal: for assessing mammographic density (MD) in a more objective and accurate way than via visual-based methods and for labeling the mammograms that are later employed to train the fully automated tool. Although most automated methods rely on supervised approaches based on a global labeling of the mammogram, the proposed method relies on pixel-level labeling, allowing better tissue classification and density measurement on a continuous scale. The fully automated method presented combines a classification scheme based on local features and thresholding operations that improve the performance of the classifier. A dataset of 655 mammograms was used to test the concordance of both approaches in measuring MD. Three expert radiologists measured MD in each of the mammograms using the semi-automated tool (DM-Scan). It was then measured by the fully automated system and the correlation between both methods was computed. The relation between MD and breast cancer was then analyzed using a case–control dataset consisting of 230 mammograms. The Intraclass Correlation Coefficient (ICC) was used to compute reliability among raters and between techniques. The results obtained showed an average ICC = 0.922 among raters when using the semi-automated tool, whilst the average correlation between the semi-automated and automated measures was ICC = 0.838. In the case–control study, the results obtained showed Odds Ratios (OR) of 1.38 and 1.50 per 10% increase in MD when using the semi-automated and fully automated approaches respectively. It can therefore be concluded that the automated and semi-automated MD assessments present a good correlation. Both the methods also found an association between MD and breast cancer risk, which warrants the proposed tools for breast cancer risk prediction and clinical decision making. A full version of the DM-Scan is freely available. 相似文献
15.
16.
María-José Villanueva Mónica Morcillo María-Dolores Tenorio Inmaculada Mateos-Aparicio Víctor Andrés Araceli Redondo-Cuenca 《European Food Research and Technology》2014,238(3):409-416
The intake of Himanthalia elongata and Gigartina pistillata from the Spanish Atlantic coasts was evaluated in Wistar rats. Both seaweed diets showed higher (p < 0.001) faecal excretion. Colonic fermentation increased (p < 0.001) total short-chain fatty acids (SCFAs) in Himanthalia-fed rats due to the higher (p < 0.001) levels of acetic, propionic and butyric acids. The intake of Gigartina increased (p < 0.001) propionic acid and decreased (p < 0.001) butyric acid. The apparent absorption and true retention of calcium and magnesium enhanced (p < 0.05) with Himanthalia diet, while Gigartina produced no significant effect. The serum concentration of HDL-C increased (p < 0.01), triglycerides (TGL) decreased (p < 0.001) and bile acids diminished (p < 0.001) in faeces of Himanthalia-fed rats. The Gigartina diet produced a decrease (p < 0.001) in TGL, total cholesterol (p < 0.01) and LDL-C (p < 0.05) in serum and reduced TGL in liver (p < 0.001). Thus, both seaweeds improved the lipid profile, and Himanthalia increased SCFA production and the absorption and retention of Ca and Mg as a result of the gut fermentation. 相似文献
17.
18.
Maria Elenice dos Santos Alicia Castro Inmaculada Martinez Paulo Noronha Lisboa-Filho Octavio Peña 《Ceramics International》2014
Multiferroic materials showing magnetoelectric coupling are required in various technological applications. Many synthetical approaches can be used to improve the magnetic and/or electrical properties, in particular when the materials exhibit cationic valence fluctuations, as in the Co2MnO4 cubic spinel. In this compound, Co and Mn ions are in competition at the tetrahedral and octahedral positions, depending on their various oxidation states. The Co2MnO4 was prepared following two techniques: by a soft chemical route based on a modified polymer precursor method, and by a mechanoactivation route. Both approaches yield polycrystalline powders, but their crystallites sizes and particles morphologies differ as a function of the calcination conditions. The magnetic characterization (ZFC/FC cycles, ordering temperatures, ferromagnetic coercive fields and saturation magnetizations) showed that the synthesis procedure influenced the physical properties of Co2MnO4 mainly through the size of the magnetic domains, which play an important role on the magnetic interactions between the Co/Mn cations. 相似文献
19.
Karola B?hme Inmaculada C. Fern��ndez-No Jose M. Gallardo Benito Ca?as Pilar Calo-Mata 《Food and Bioprocess Technology》2011,4(6):907-918
Foodborne intoxications caused by the consumption of fish and other products of marine origin contaminated with bacterial
pathogens are an ever-present threat, either due to bacteria and/or its metabolites. In addition, the rapid spoilage of seafood
due to microbial activity, results in high economic losses. The development of the microbiota in seafood products depends
on the microbiological ambience of capture, processing and storage, and the applied preservation method. Thus, pathogenic
and spoilage bacterial species in seafood may come from the indigenous microbiota of the aquatic ambience or are introduced
by contamination during processing. Rapid and accurate bacterial species identification is essential for an effective control
program to ensure safety and quality of either processed or minimally processed seafood. In the present work, matrix-assisted
laser desorption ionization-time of flight mass spectrometry was successfully applied to identify 26 bacterial strains isolated
from fresh fish and processed seafood samples. The approach was based on the comparison of unknown spectra to a reference
spectral library and demonstrated to be a fast and accurate technique for bacterial species differentiation, which can be
used for the rapid identification of foodborne pathogens and spoilage bacteria potentially present in products of marine origin. 相似文献
20.
Inmaculada Mateos-Aparicio Araceli Redondo-Cuenca María-José Villanueva-Suárez María-Aurora Zapata-Revilla María-Dolores Tenorio-Sanz 《LWT》2010,43(9):1467-1470
Disposal of by-products generated by plant food processing represent an important problem in the industry, but these by-products are also promising sources of compounds which may be used for their technological or nutritional properties, and today they are considered as a possible source of functional compounds. This work has contributed to the knowledge of three legume by-products, pea pod (Pisum sativum L.), broad bean pod (Vicia faba L.) and okara from soybean (Glycine max L.). These three by-products have in common that their major fraction is dietary fibre (pea pod: 58.6 g/100 g; okara: 54.3 g/100 g; broad bean pod: 40.1 g/100 g). Sucrose, glucose and fructose are the most important soluble sugars in both pods; however α-galactosides (stachyose and raffinose) are in greater concentration in okara. Protein is also a considerable component, although in higher amount in okara than in pods. Okara presents a large quantity of fat however both pods show similar low contents. Linoleic acid is the most important fatty acid; oleic acid is remarkable in okara and pea pod and linolenic acid in broad bean pod. Mineral amount is major in by-product pods than in okara, and the most important minerals are potassium, calcium and iron. 相似文献