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71.
Ana Beatriz Lopes de Sousa Jabbour Charbel José Chiappetta Jabbour Joseph Sarkis Kannan Govindan 《Clean Technologies and Environmental Policy》2014,16(1):7-9
Brazil, one of the world’s largest developing countries, has recently introduced a new solid waste management regulatory policy. This new regulatory policy will have implications for a wide variety of stakeholders and sets the stage for opportunities and lessons to be learned. These issues are discussed in this article. 相似文献
72.
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
73.
Ângela Fernandes João C. M. Barreira Amilcar L. Antonio M. Beatriz P. P. Oliveira Anabela Martins Isabel C. F. R. Ferreira 《Food and Bioprocess Technology》2014,7(6):1606-1617
Mushrooms are very perishable foods due to their high susceptibility to moisture loss, changes in color and texture, or microbiological spoilage. Drying is considered as the most appropriate method to prevent these alterations, but it has some limitations, such as shrinkage, enzymatic and non-enzymatic browning reactions, and oxidation of lipids and vitamins. According to previous studies, irradiation might effectively attenuate the undesirable changes caused by drying process, ensuring also higher shelf-life of mushrooms and their decontamination. Electron-beam irradiation presents some technological advantages, since it allows higher dose rates and the possibility to be used in most foods/or thin products in a short period. Herein, the combined effects of electron-beam irradiation (0, 0.5, 1 and 6 kGy) and storage time (0, 6 and 12 months) were evaluated by measuring changes in nutritional parameters, namely, free sugars, tocopherols, fatty acids and antioxidant activity. As indicated by linear discriminant analysis, storage time had a higher effect on all the evaluated parameters, except fatty acids, which suffer significant changes with both factors. Overall, the obtained results indicate that electron-beam irradiation might be considered as a suitable technique, allowing long-lasting conservation periods while reducing changes induced by drying treatment. 相似文献
74.
Improved pretreatments applied to the sugarcane bagasse and release of lignin and hemicellulose from the cellulose‐enriched fractions by sulfuric acid hydrolysis 下载免费PDF全文
75.
76.
David Deibe Margarita Amor Ramón Doallo David Miranda Miguel Cordero 《International journal of remote sensing》2017,38(3):827-849
In recent years lidar technology has experienced a noticeable increase in its relevance and usage in a number of scientific fields. Therefore, software capable of handling lidar data becomes a key point in those fields. In this article, we present GPU-based viewer lidar (GVLiDAR), a novel web framework for visualization and geospatial measurement of lidar data point sets. The design of the framework is focused on achieving three key objectives: performance in terms of real-time interaction, functionality, and online availability for the lidar datasets. All lidar files are pre-processed and stored in a lossless data structure, which minimizes transfer requirements and offers an on-demand lidar data web framework. 相似文献
77.
Long‐term expansion of human induced pluripotent stem cells in a microcarrier‐based dynamic system 下载免费PDF全文
78.
D. Pereira J. Gandra J. Pamies-Teixeira R.M. Miranda P. Vilaça 《Journal of Materials Processing Technology》2014,214(12):2858-2868
Friction surfacing was performed to produce multi-layer coatings of AISI 1024, AISI 1045 and AISI H13 over mild steel substrates where a continuous joining was achieved between adjacent layers and between the clad and the substrate. Microscopic and hardness characterization revealed the presence of bainitic and martensitic microstructures which influenced the hardness of the coatings. The study aimed to determine which material combination was more wear-resistant. The analysis suggested that AISI 1024 presents the least wear, both in terms of friction coefficient and wear rate. This is due to the formation of adherent protective oxide layer which is not present in both the AISI 1045 and AISI H13 steels. 相似文献
79.
F. Kahleyss R. Lima de Miranda T. Surmann C. Zamponi C. Machai D. Biermann E. Quandt 《Journal of Materials Engineering and Performance》2011,20(4-5):500-505
Nowadays, many manufacturing processes require the machining of complex forms with a high aspect ratio or cavities. Tools with a long overhang length are a common method to meet these requirements. Typical examples for this are boring bars for bore-turning and the milling with very long cutters. These tools tend to vibrate strongly due to their slender shape. The stress-induced transformation of austenite to martensite and the distinctive hysteresis loop allow the NiTi shape memory alloys (SMA) to absorb vibration energy. This article describes the innovative approach to dampen process vibrations by coating the tool shafts of cutting tools with long overhang with NiTi thin films. It explores how these thin films can be applied on polished tungsten carbide shafts and how their modal parameters are modified by these coatings. In a further step, this knowledge is used to calculate stability charts of corresponding machining processes. The study reported in this article identified the stabilizing effects of coatings with a thickness of 2-4 ??m on milling processes. The minimum stability limit was increased by up to 200%. 相似文献
80.
Ray Lara A.; Miranda Robert Jr.; MacKillop James; McGeary John; Tidey Jennifer W.; Rohsenow Damaris J.; Gwaltney Chad; Swift Robert W.; Monti Peter M. 《Canadian Metallurgical Quarterly》2009,17(2):122
Topiramate, an anticonvulsant medication, is an efficacious treatment for alcohol dependence. To date, little is known about genetic moderators of side effects from topiramate. The objective of this study was to examine 3 single nucleotide polymorphisms (SNPs) of the glutamate receptor GluR5 gene (GRIK1) as predictors of topiramate-induced side effects in the context of a laboratory study of topiramate. Heavy drinkers (n = 51, 19 women and 32 men), 75% of whom met criteria for an alcohol use disorder, completed a 5-week dose escalation schedule to a target dose of either 200 or 300 mg or matched placebo. The combined medication groups were compared with placebo-treated individuals for side effects at target dose. Analyses revealed that an SNP in intron 9 of the GRIK1 gene (rs2832407) was associated with the severity of topiramate-induced side effects and with serum levels of topiramate. Genes underlying glutamatergic neurotransmission, such as the GRIK1 gene, may help predict heterogeneity in topiramate-induced side effects. Future studies in larger samples are needed to more fully establish these preliminary findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献