420 research outputs found

    Comparison of Monomethylhydrazine/Hydroxypropylcellulose and Hydrocarbon/Silica Gels

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    Experimental studies have been performed to investigate rheology and droplet burning with different types of gelled propellants. Monomethylhydrazine has been gelled with organic hydroxypropylcellulose. JP-8 and RP-1 hydrocarbon gels have been produced with inorganic fumed silica particles. Rheological characterization showed the differences in terms of viscosity and yield stress behavior due to different types of gelling agents. Herschel-Bulkley and Carreau-Yasuda models have been used to characterize the gels with inorganic and organic gelling agents, respectively. First experiments with the Monomethylhydrazine/hydroxypropylcellulose gels showed a typical swelling process during combustion with a flexible viscous droplet surface. Contrary to that, the hydrocarbon/silica gels burned while a rigid silica structure was built, which remained unburned. Burning drop measurements have been compared to the d^2-squared law

    FOULING IN A CENTRITHERM EVAPORATOR WITH WHEY SOLUTIONS

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    Fouling caused by sweet cheese whey and reconstituted whey powder solutions was studied in a Centritherm evaporator, the behaviour being estimated by measuring the change in the overall heat transfer coefficients with the time. It was found that there was no fouling detectable for the reconstituted whey powder solution. For sweet cheese whey, the fouling rate was linked strongly with the evaporating temperature and temperature difference. Visual observation showed that the deposit layer on the evaporator surface was very thin and soft, and like the type A milk deposit described by other investigators. A high velocity of liquid film delayed the formation of deposit on the surface. Some interactions between the evaporation temperature, feed flow rate, rotating speed and temperature difference are discussed. The fouling is caused by denaturation of bovine serum albumin in a second order rate reaction

    An energy efficiency analysis of single point incremental forming as an approach for sheet metal based component reuse

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    Producing materials causes about 25% of all anthropogenic CO2 emissions. Metals play a significant role, steel and aluminum account for 24% and 3% of worldwide material related emissions respectively. Fostering resources efficiency strategies in the field of sheet components could lead to a significant environmental impact reduction. Reshaping could be one of the most efficient strategy to foster material reuse and lower the environmental impact due to material production. Specifically, for aluminum recycling, the overall energy efficiency of conventional route is very low and, more importantly, permanent material losses occur during re-melting because of oxidation. The present paper aims at presenting the technical feasibility of Single Point Incremental Forming (SPIF)-based reshaping approach. Change in shape of aluminum stamped part is obtained through SPIF process implementation. Preliminary energy savings quantification through life cycle energy and material flows modelling are provided, energy efficiency of conventional recycling approach and SPIF-based reshaping routes are analyzed and compared

    Biomarkers Identification in the Microenvironment of Oral Squamous Cell Carcinoma: A Systematic Review of Proteomic Studies

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    an important determinant for oral squamous cell carcinoma (OSCC) onset and outcome is the composition of the tumor microenvironment (TME). thus, the study of the interactions occurring among cancer cells, immune cells, and cancer-associated fibroblasts within the TME could facilitate the understanding of the mechanisms underlying OSCC development and progression, as well as of its sensitivity or resistance to the therapy. In this context, it must be highlighted that the characterization of TME proteins is enabled by proteomic methodologies, particularly mass spectrometry (MS). aiming to identify TME protein markers employable for diagnosing and prognosticating OSCC, we have retrieved a total of 119 articles spanning 2001 to 2023, of which 17 have passed the selection process, satisfying all its criteria. We have found a total of 570 proteins detected by MS-based proteomics in the TME of OSCC; among them, 542 are identified by a single study, while 28 are cited by two or more studies. these 28 proteins participate in extracellular matrix remodeling and/or energy metabolism. here, we propose them as markers that could be used to characterize the TME of OSCC for diagnostic/prognostic purposes. noteworthy, most of the 28 individuated proteins share one feature: being modulated by the hypoxia that is present in the proliferating OSCC mass

    Evaluación mediante teledetección del efecto de canalizaciones sobre el humedal del Saladillo, Argentina

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    Los humedales son ecosistemas naturales cuya dinámica está determinada principalmente por la presencia de agua. Generalmente se los identifica como áreas que se inundan temporariamente donde el agua subterránea aflora en la superficie, o con áreas con suelos de baja permeabilidad que permanecen cubiertos por agua poco profunda. El agua, por lo tanto, juega un rol fundamental en la determinación de su estructura y funciones ecológicas. Los datos provistos por imágenes satelitales son una herramienta apropiada para analizar humedales y los cambios ocurridos en ellos a lo largo del tiempo. Los Bañados del Saladillo son un complejo de humedales en el centro de Argentina, de gran importancia para la preservación de aves acuáticas. Estos bañados han sufrido profundos cambios por el avance de la agricultura y las canalizaciones realizadas para mitigar el efecto de inundaciones en el sudeste de la provincia de Córdoba de este país. El objetivo del trabajo fue conocer la condición histórica y presente de los Bañados del Saladillo, y analizar los efectos de las canalizaciones sobre los mismos. Se estudiaron 6 imágenes satelitales que se clasificaron con ENVI 4.8 (ITT, 2010), representando la estación seca y húmeda en tres períodos: previo a las canalizaciones (1996); posterior a las canalizaciones (2004-2006); período reciente (2010-2011). Éstas fueron seleccionadas de acuerdo a las precipitaciones acumuladas en 6 meses previos para que fueran comparables. El área de lagunas se redujo entre un 70% (estación húmeda) y un 33% (estación seca). Los mayores cambios observados en la estación húmeda se reflejaron también en la reducción del número de lagunas (40%), la variabilidad de su tamaño (66%), el perímetro de las mismas (28%) y el incremento de la distancia entre ellas. Más allá de la mitigación de las inundaciones, las canalizaciones favorecieron el avance de la agricultura sobre áreas históricamente inundadas en la estación lluviosa, poniendo en riesgo la persistencia de este importante humedal del sudeste de Córdoba en el centro de Argentina. Los resultados obtenidos representan una herramienta útil al momento de tomar decisiones para el manejo y conservación de estos relictos de hábitat natural y su biodiversidad.Wetlands are natural ecosystems whose dynamics is mainly determined by the presence of water. They are generally identified as temporarily flooded areas where groundwater emerges at the surface, or areas with low permeability soils that remain covered by shallow water. The water, therefore, plays a key role in determining the structure and ecological functions of wetlands. Data provided by satellite images are an appropriate tool for analyzing wetlands and their changes over time. The Saladillo Wetlands are a complex of marshlands in the centre of Argentina, of great importance to the preservation of birds. These marshes have suffered profound changes caused by the advancement of agriculture and channels made to mitigate the effects of flooding in the southeast of the province of Cordoba in this country. The objective of our work was to know the historical and present condition of the Saladillo Wetlands, and to analyze the effects of the channelization on them. We studied six satellite images classified with ENVI 4.8. These images represented the dry and the wet season into three periods: prior to the channelization (1996), after the channelization (2004-2006); and recent period (2010- 2011). They were selected according to the accumulated rainfall during the previous 6 months to make them comparable. The pond area was reduced by 70% (wet season) and 33% (dry season). The major changes observed in the wet season also reflected in the reduction in the number of ponds (40%), the variability of their size (66%), the perimeter of flooded areas (28%) and an increasing the distance between ponds. Beyond the flood mitigation, the channelization favoured the advancement of agriculture on areas historically flooded in the rainy season, threatening the persistence of this important wetland of the southeast of Cordoba in central Argentina. Our results represent a useful tool for the management and conservation of these remnants of natural habitat and biodiversity.Fil: Lopez, C.. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; ArgentinaFil: Brandolin, Pablo Germán. Asociación Civil Amigos para la Conservación de las Aves, Córdoba; ArgentinaFil: Campanella, O. R.. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Departamento de Geologia; ArgentinaFil: Martino, A. L.. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; ArgentinaFil: de Angelo, Carlos Daniel. Universidad Nacional de Misiones. Facultad de Ciencias Forestales. Instituto de Biologia Subtropical - Sede Puerto Iguazu; Argentin

    Thermo-mechanical behaviour of a compacted swelling clay

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    Compacted unsaturated swelling clay is often considered as a possible buffer material for deep nuclear waste disposal. An isotropic cell permitting simultaneous control of suction, temperature and pressure was used to study the thermo-mechanical behaviour of this clay. Tests were performed at total suctions ranging from 9 to 110 MPa, temperature from 25 to 80 degrees C, isotropic pressure from 0.1 to 60 MPa. It was observed that heating at constant suction and pressure induces either swelling or contraction. The results from compression tests at constant suction and temperature evidenced that at lower suction, the yield pressure was lower, the elastic compressibility parameter and the plastic compressibility parameter were higher. On the other hand, at a similar suction, the yield pressure was slightly influenced by the temperature; and the compressibility parameters were insensitive to temperature changes. The thermal hardening phenomenon was equally evidenced by following a thermo-mechanical path of loading-heating-cooling-reloading

    ODTN: Open Disaggregated Transport Network. Discovery and Control of a Disaggregated Optical Network through Open Source Software and Open APIs

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    ONOS discovers and manages a topology made of Transponders and a dedicated OLS, using standard protocols (NETCONF/RESTCONF) and models (OpenConfig/TAPI). The demo is a joint collaboration, towards production deployment, between 3 operators and 2 equipment vendors

    Occupational exposure to electromagnetic fields in magnetic resonance environment: an update on regulation, exposure assessment techniques, health risk evaluation, and surveillance

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    Magnetic resonance imaging (MRI) is one of the most-used diagnostic imaging methods worldwide. There are ∼50,000 MRI scanners worldwide each of which involves a minimum of five workers from different disciplines who spend their working days around MRI scanners. This review analyzes the state of the art of literature about the several aspects of the occupational exposure to electromagnetic fields (EMF) in MRI: regulations, literature studies on biological effects, and health surveillance are addressed here in detail, along with a summary of the main approaches for exposure assessment. The original research papers published from 2013 to 2021 in international peer-reviewed journals, in the English language, are analyzed, together with documents published by legislative bodies. The key points for each topic are identified and described together with useful tips for precise safeguarding of MRI operators, in terms of exposure assessment, studies on biological effects, and health surveillance. Graphical abstract: [Figure not available: see fulltext.

    A Deep Learning based Pipeline for Efficient Oral Cancer Screening on Whole Slide Images

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    Oral cancer incidence is rapidly increasing worldwide. The most important determinant factor in cancer survival is early diagnosis. To facilitate large scale screening, we propose a fully automated pipeline for oral cancer detection on whole slide cytology images. The pipeline consists of fully convolutional regression-based nucleus detection, followed by per-cell focus selection, and CNN based classification. Our novel focus selection step provides fast per-cell focus decisions at human-level accuracy. We demonstrate that the pipeline provides efficient cancer classification of whole slide cytology images, improving over previous results both in terms of accuracy and feasibility. The complete source code is available at https://github.com/MIDA-group/OralScreen.Comment: Accepted to ICIAR 202
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