465 resultados para mold


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Le sel (NaCl) joue plusieurs rôles importants dans les fromages aux niveaux technologique, microbiologique et organoleptique. Cependant, le sodium, un facteur de risque des maladies cardiovasculaires, est consommé en trop grande quantité par les Canadiens. Comme la réduction du sodium pourrait affecter la texture des fromages à pâte molle à croûte fleurie et la libération des nutriments pendant la digestion, l’impact de la réduction du sodium sur la bioaccessibilité des protéines dans le fromage Brie a été étudié. Ainsi, la composition et les caractéristiques texturales de fromages Brie ayant différentes teneurs en sodium (standard, réduite, substituée au KCl) ont été analysées. Une réduction du sodium de 23 % a été obtenue pour les fromages réduits en sodium. Le temps d’affinage affecte la protéolyse et la texture des fromages. La cinétique de dégradation de la matrice fromagère et la libération des protéines ont été déterminées par une approche de digestion in vitro. La désintégration de la matrice fromagère et la libération des protéines pendant la digestion in vitro ne sont pas différentes entre les fromages expérimentaux. Ces travaux démontrent qu’il est possible de réduire le sodium sans affecter le profil de protéolyse et la texture pendant l’affinage du fromage Brie ainsi que son comportement à la digestion.

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Compaction control using lightweight deflectometers (LWD) is currently being evaluated in several states and countries and fully implemented for pavement construction quality assurance (QA) by a few. Broader implementation has been hampered by the lack of a widely recognized standard for interpreting the load and deflection data obtained during construction QA testing. More specifically, reliable and practical procedures are required for relating these measurements to the fundamental material property—modulus—used in pavement design. This study presents a unique set of data and analyses for three different LWDs on a large-scale controlled-condition experiment. Three 4.5x4.5 m2 test pits were designed and constructed at target moisture and density conditions simulating acceptable and unacceptable construction quality. LWD testing was performed on the constructed layers along with static plate loading testing, conventional nuclear gauge moisture-density testing, and non-nuclear gravimetric and volumetric water content measurements. Additional material was collected for routine and exploratory tests in the laboratory. These included grain size distributions, soil classification, moisture-density relations, resilient modulus testing at optimum and field conditions, and an advanced experiment of LWD testing on top of the Proctor compaction mold. This unique large-scale controlled-condition experiment provides an excellent high quality resource of data that can be used by future researchers to find a rigorous, theoretically sound, and straightforward technique for standardizing LWD determination of modulus and construction QA for unbound pavement materials.

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“Parallel Ruptures: Jews of Bessarabia and Transnistria between Romanian Nationalism and Soviet Communism, 1918-1940,” explores the political and social debates that took place in Jewish communities in Romanian-held Bessarabia and the Moldovan Autonomous Soviet Socialist Republic during the interwar era. Both had been part of the Russian Pale of Settlement until its dissolution in 1917; they were then divided by the Romanian Army’s occupation of Bessarabia in 1918 with the establishment of a well-guarded border along the Dniester River between two newly-formed states, Greater Romania and the Soviet Union. At its core, the project focuses in comparative context on the traumatic and multi-faceted confrontation with these two modernizing states: exclusion, discrimination and growing violence in Bessarabia; destruction of religious tradition, agricultural resettlement, and socialist re-education and assimilation in Soviet Transnistria. It examines also the similarities in both states’ striving to create model subjects usable by the homeland, as well as commonalities within Jewish responses on both sides of the border. Contacts between Jews on either side of the border remained significant after 1918 despite the efforts of both states to curb them, thereby necessitating a transnational view in order to examine Jewish political and social life in borderland regions. The desire among Jewish secular leaders to mold their co-religionists into modern Jews reached across state borders and ideological divides and sought to manipulate respective governments to establish these goals, however unsuccessful in the final analysis. Finally, strained relations between Jews in peripheral borderlands with those at national/imperial cores, Moscow and Bucharest, sheds light on the complex circumstances surrounding the inclusion versus exclusion debates at the heart of all interwar European states and the complicated negotiations that took place within all minority communities that responded to state policies.

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El creciente peso que han alcanzado los mercados y diferentes actores económicos dentro de la escena política mundial, sugieren que estamos frente a un nuevo paradigma en lo que concierne al funcionamiento del Estado nación. El concepto de Geoeconomía surge como respuesta a los cambios que se han comenzado a configurar a partir de la segunda mitad del siglo XX, a su vez que ilustra como a través de la concepción de estrategias de control económico se puede alcanzar dominio y poder en términos internacionales, bien sea a través de los Estados de manera directa o bajo su influencia o beneplácito a través de grandes grupos económicos. En efecto, el presente trabajo de investigación aborda desde la óptica Geoeconómica la progresiva colonización que ha emprendido el sistema financiero colombiano, y más propiamente el Grupo Bancolombia, sobre una serie de activos financieros estratégicos en Centroamérica. Del mismo modo, explica cómo este fenómeno ha traído consigo cambios sustanciales en la dinámica de las relaciones internacionales de Colombia con sus vecinos, a su vez que ha propiciado las condiciones de legitimidad necesarias para una serie de actores privados que podrían llegar incluso a ser capaces de moldear en cierta medida la política interior y exterior del país, tal y como ha sucedido en algunos episodios recientes.

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At present, in large precast concrete enterprises, the management over precast concrete component has been chaotic. Most enterprises take labor-intensive manual input method, which is time consuming and laborious, and error-prone. Some other slightly better enterprises choose to manage through bar-code or printing serial number manually. However, on one hand, this is also labor-intensive, on the other hand, this method is limited by external environment, making the serial number blur or even lost, and also causes a big problem on production traceability and quality accountability. Therefore, to realize the enterprise’s own rapid development and cater to the needs of the time, to achieve the automated production management has been a big problem for a modern enterprise. In order to solve the problem, inefficiency in production and traceability of the products, this thesis try to introduce RFID technology into the production of PHC tubular pile. By designing a production management system of precast concrete components, the enterprise will achieve the control of the entire production process, and realize the informatization of enterprise production management. RFID technology has been widely used in many fields like entrance control, charge management, logistics and so on. RFID technology will adopt passive RFID tag, which is waterproof, shockproof, anti-interference, so it’s suitable for the actual working environment. The tag will be bound to the precast component steel cage (the structure of the PHC tubular pile before the concrete placement), which means each PHC tubular pile will have a unique ID number. Then according to the production procedure, the precast component will be performed with a series of actions, put the steel cage into the mold, mold clamping, pouring concrete (feed), stretching, centrifugalizing, maintenance, mold removing, welding splice. In every session of the procedure, the information of the precast components can be read through a RFID reader. Using a portable smart device connected to the database, the user can check, inquire and management the production information conveniently. Also, the system can trace the production parameter and the person in charge, realize the traceability of the information. This system can overcome the disadvantages in precast components manufacturers, like inefficiency, error-prone, time consuming, labor intensity, low information relevance and so on. This system can help to improve the production management efficiency, and can produce a good economic and social benefits, so, this system has a certain practical value.

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Soybean plays an important role in the Brazilian agriculture being one of the products most exported by the country. Its yield may be affected by diseases such as white mold, caused by the fungus Sclerotinia sclerotiorum Lib. de Bary, which, under favorable field conditions prevents the crop of expressing all its productive potential. The fungus is cosmopolitan and infects more than 400 species of plants. This disease is difficult to control, and the use of chemicals has not been sufficient to avoid significant losses, thus, this products are expensive and may cause environmental damage. Alternative methods, such as foliar fertilizers based on potassium phosphite, can also be used in the management of this disease. In this context, this work aimed to study different sources of potassium phosphite and its effects in the control of white mold in soybeans, as well as the time of application in culture, its action in inducing plants defense responses and/or its influence over the seeds quality. The effect of phosphites, over the pathogen, was evaluated in vitro, on mycelial inhibition, the mass of dry mycelium and germination of sclerotia. In all tests, the following phosphites were utilized: Phosphite A (P2O5-40%; K2O-20% - 1 L/ha); Phosphite B (P2O5-40%; K2O-28% - 1 L/ha); Phosphite C (P2O5-40%; K2O-20% - 1 L/ha) e Phosphite D (P2O5-30%; K2O-20% - 2,4 L/ha). At the induction of resistance tests were evaluated the synthesis of phytoalexin in soybean cotyledons and the enzymes FAL and POX evaluated in seedlings in growing chamber, sprayed with phosphites and the fungicide fluazinam. Field experiment was carried out at Coronel Domingos Soares-PR, in the 2012/2013 season, in an area with natural infestation of the pathogen. Soybean cultivar BMX Active was no-till seeded with 0,5m between rows. The experimental was laid out as a factorial 5 x 4 scheme (treatment x application time). Phosphites sources were used, as described above, and water was sprayed in the control treatment. Treatments were applied at four different growth stages: V4, V4 + R1, R1 and R2 at the rates recommended by the manufacturer. Soybean yield components and seeds and health and physiological quality were evaluated after harvesting. None of the tested phosphites affected mycelial growth and sclerotia germination or influenced phytoalexin synthesis. Phosphites C and D stood out due to an increasing in the phenylalanine ammonia-lyase activity 48 hours after its inoculation. These same products also induced the synthesis and peroxidases and phosphite C kept the levels of this enzyme elevated up to 72 hours after inoculation. At the field trials, phosphites C and D stood out in the control of white mold. There was no significant interaction of potassium phosphite on physiological and sanitary quality of the seeds.

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The engineering of liquid behavior on surfaces is important for infrastructure, transportation, manufacturing, and sensing. Surfaces can be rendered superhydrophobic by microstructuring, and superhydrophobic devices could lead to practical corrosion inhibition, self-cleaning, fluid flow control, and surface drag reduction. To more fully understand how liquid interacts with microstructured surfaces, this dissertation introduces a direct method for determining droplet solid-liquid-vapor interfacial geometry on microstructured surfaces. The technique performs metrology on molten metal droplets deposited onto microstructured surfaces and then frozen. Unlike other techniques, this visualization technique can be used on large areas of curved and opaque microstructured surfaces to determine contact line. This dissertation also presents measurements and models for how curvature and flexing of microstructured polymers affects hydrophobicity. Increasing curvature of microstructured surfaces leads to decreased slide angle for liquid droplets suspended on the surface asperities. For a surface with regularly spaced asperities, as curvature becomes more positive, droplets suspended on the tops of asperities are suspended on fewer asperities. Curvature affects superhydrophobicity because microscopic curvature changes solid-liquid interaction, pitch is altered, and curvature changes the shape of the three phase contact line. This dissertation presents a model of droplet interactions with curved microstructured surfaces that can be used to design microstructure geometries that maintain the suspension of a droplet when curved surfaces are covered with microstructured polymers. Controlling droplet dynamics could improve microfluidic devices and the shedding of liquids from expensive equipment, preventing corrosion and detrimental performance. This dissertation demonstrates redirection of dynamic droplet spray with anisotropic microstructures. Superhydrophobic microstructured surfaces can be economically fabricated using metal embossing masters, so this dissertation describes casting-based microfabrication of metal microstructures and nanostructures. Low melting temperature metal was cast into flexible silicone molds which were themselves cast from microfabricated silicon templates. The flexibility of the silicone mold permits casting of curved surfaces, which this dissertation demonstrates by fabricating a cylindrical metal roller with microstructures. The metal microstructures can be in turn used as a reusable molding tool. This dissertation also describes an industrial investment casting process to produce aluminum molds having integrated microstructures. Unlike conventional micromolding tools, the aluminum mold was large and had complex curved surfaces. The aluminum was cast into curved microstructured ceramic molds which were themselves cast from curved microstructured rubber. Many structures were successfully cast into the aluminum with excellent replication fidelity, including circular, square, and triangular holes. This dissertation demonstrates molding of large, curved surfaces having surface microstructures using the aluminum mold. This work contributes a more full understanding of the phenomenon of superhydrophobicity and techniques for the economic fabrication of superhydrophobic microstructures.

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Sodium is an essential nutrient with important functions in the organism, however, its ingestion in excess may cause various health problems such as arterial hypertension, brain diseases, heart failure and chronic renal failure. In this context, the present study proposes to prepare Minas Padrão cheese with different contents of sodium with the objective of evaluating the effect of the addition of potassium chloride in sensory characteristics and hysicochemical properties, as well as in the proximal composition and in microbiological quality. The cheeses were elaborate in concentrations of 100% of NaCl (C), 80% of NaCl + 20% of KCl (T1), 60% of NaCl + 40% of KCl (T2), 40% of NaCl + 60% of KCl (T3) and 20% of NaCl + 80% of KCl (T4) and stored for 20 days at 10 ºC. The proximal composition and physicochemical was based on the determination of moisture content, fat, protein, ash, chloride, sodium, potassium, titratable acidity and pH of all treatments after 20 days of storage. The microbiological quality of the samples was monitored through the count of Total Coliforms and Escherichia coli, Staphylococcus aureus, Salmonella spp., mold and yeast in the first and fifteenth day of storage. The sensorial characterization was performed by the technique of Free Profile choice. The results showed that the replacement of sodium chloride by potassium in the Minas Padrão cheese in concentration higher than 40% presented significantly higher moisture contents. Cheese with a reduction greater than 60% of sodium obtained significantly effect in the titratable acidity, presenting higher values compared to the other treatments. The cheese with 20% of salt replacement did not differ statistically in relation to the control. When the proportion of substituent was increased, a significant reduction of the sodium content of up to 73% was observed. As the sodium was replaced by potassium in cheese, the potassium content increased significantly, stablishing a reduction of 82% in relation to the control. There was no effect to sodium substitution by potassium in fat, protein, ash and chlorides, as well as the pH values. The microbiological results were in accordance with the current legislation, therefore suitable to be eaten. According to the Free Profile Choice technique it was observed that the control C cheese (100% of NaCl) showed results very close to the other treatments, differing only in flavor attributes. The replacement of sodium by potassium in proportions of 20% contributed to a bitter taste detected by the tasters. Whereas, the appearance, flavor and texture attributes showed no significant differences compared to the Minas Padrão cheese.

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In many occupational settings an exposure to fungi occurs. Fungal exposure may occur for instance in the form of dermatocytes, yeasts or mold. Associated to the fungi themselves an exposure to cell wall components like ß(1 ? 3)-D-glucans, to mycotoxins or to microbial volatile compounds can occur. Health hazards may differ across species because fungi may produce different allergens and mycotoxins, and some species can infect humans. Occupational settings are often characterized by special exposure conditions with respect to duration, frequency and especially to the level of exposure resulting at least sometimes to high or very high fungal exposure. Because of these special conditions occupational settings are suitable for epidemiologic studies. However, the knowledge about occupational exposure to fungi and associated compounds like mycotoxins is still fragmentary and not well disseminated. An indication for a high fungal exposure is for instance the handling of dry natural products like grain, hay or herbal plants with a high specific surface and the tendency to release dust during handling. The fungal components often form the determinative part of such dusts and might be a vehicle to respiratory airways. The authors will present results of exposure measurements of occupational settings and exposure conditions which are only rarely investigated.

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A descriptive study was developed in order to compare indoor and outdoor air contamination caused by fungi and particles in seven poultry units. Twenty eight air samples of 25 litters were collected through the impaction method on malt extract agar. Air sampling and particles concentration measurement were done in the interior and also outside premises of the poultries’ pavilions. Regarding the fungal load in the air, indoor concentration of mold was higher than outside air in six poultry units. Twenty eight species / genera of fungi were identified indoor, being Scopulariopsis brevicaulis (40.5%) the most commonly isolated species and Rhizopus sp. (30.0%) the most commonly isolated genus. Concerning outdoor, eighteen species/genera of fungi were isolated, being Scopulariopsis brevicaulis (62.6%) also the most isolated. All the poultry farms analyzed presented indoor fungi different from the ones identified outdoors. Regarding particles’ contamination, PM2.5, PM5.0 and PM10 had a statistically significant difference (Mann-Whitney U test) between the inside and outside of the pavilions, with the inside more contaminated (p=.006; p=.005; p=.005, respectively). The analyzed poultry units are potential reservoirs of substantial amounts of fungi and particles and could therefore free them in the atmospheric air. The developed study showed that indoor air was more contaminated than outdoors, and this can result in emission of potentially pathogenic fungi and particles via aerosols from poultry units to the environment, which may post a considerable risk to public health and contribute to environmental pollution.

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Nonlinear thermo-mechanical properties of advanced polymers are crucial to accurate prediction of the process induced warpage and residual stress of electronics packages. The Fiber Bragg grating (FBG) sensor based method is advanced and implemented to determine temperature and time dependent nonlinear properties. The FBG sensor is embedded in the center of the cylindrical specimen, which deforms together with the specimen. The strains of the specimen at different loading conditions are monitored by the FBG sensor. Two main sources of the warpage are considered: curing induced warpage and coefficient of thermal expansion (CTE) mismatch induced warpage. The effective chemical shrinkage and the equilibrium modulus are needed for the curing induced warpage prediction. Considering various polymeric materials used in microelectronic packages, unique curing setups and procedures are developed for elastomers (extremely low modulus, medium viscosity, room temperature curing), underfill materials (medium modulus, low viscosity, high temperature curing), and epoxy molding compound (EMC: high modulus, high viscosity, high temperature pressure curing), most notably, (1) zero-constraint mold for elastomers; (2) a two-stage curing procedure for underfill materials and (3) an air-cylinder based novel setup for EMC. For the CTE mismatch induced warpage, the temperature dependent CTE and the comprehensive viscoelastic properties are measured. The cured cylindrical specimen with a FBG sensor embedded in the center is further used for viscoelastic property measurements. A uni-axial compressive loading is applied to the specimen to measure the time dependent Young’s modulus. The test is repeated from room temperature to the reflow temperature to capture the time-temperature dependent Young’s modulus. A separate high pressure system is developed for the bulk modulus measurement. The time temperature dependent bulk modulus is measured at the same temperatures as the Young’s modulus. The master curve of the Young’s modulus and bulk modulus of the EMC is created and a single set of the shift factors is determined from the time temperature superposition. The supplementary experiments are conducted to verify the validity of the assumptions associated with the linear viscoelasticity. The measured time-temperature dependent properties are further verified by a shadow moiré and Twyman/Green test.

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Mycotoxins are an important group of naturally occurring substances known to contaminate a huge variety of agricultural products, feed and food commodities. The main concern is their widespread presence and toxic effects on humans and animals as they have been described as cytotoxic, nephrotoxic, hepatotoxic, teratogenic, immunosuppressive, mutagenic and/or carcinogenic. However, until now, risk assessments and regulations have usually been performed on individual mycotoxins despite humans and animals are being frequently exposed to a multitude of mycotoxins simultaneously. Moreover, even though some exposures through inhalation and dermal contact may potentially occur, only oral ingestion has been considered as the sole route of exposure in all the evaluations. However, more recent studies have also demonstrated airborne exposure to mycotoxins in different occupational settings with emphasis on agricultural professions. In these cases, skin contact with mold-infested substrates and inhalation of spore-borne toxins are the most important sources of exposure. Still, mycotoxins are not normally recongnize as na occupational hazard and exposure is different from the one ocurring by food intake. In this case, exposure is charaterized to be acute and simultaneous to other mycotoxins and also to fungi and dust. All these features increase the challenge implicated in the risk assessment process. Some topics will be presented and discussed in detailed such as: What occupational settings should be consider in this case; possible exposure routes; exposure characterization; how to assess exposure; co-exposure; aggregate exposure and cumulative risk assessment.

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Résumé : PROBLÉMATIQUE: L’exposition résidentielle à l’humidité excessive ou aux moisissures est maintenant reconnue comme un facteur important influençant la santé respiratoire. Cette problématique a été peu étudiée chez les étudiants universitaires, bien que vulnérables par leur faible revenu et leur statut de locataire. OBJECTIFS: Cette maîtrise vise à décrire la prévalence (a) de l’exposition résidentielle à l’humidité excessive ou aux moisissures et (b) des maladies respiratoires chez les étudiants universitaires, ainsi qu’à (c) examiner l’association entre l’exposition résidentielle à l’humidité excessive ou aux moisissures et ces maladies. MÉTHODES: En 2014, une enquête électronique a été réalisée auprès de 2097 étudiants enregistrés à l’Université de Sherbrooke (Québec, Canada). Lorsque possible, des questions et des scores validés ont été utilisés pour estimer les prévalences des maladies respiratoires (rhinite allergique, asthme et infections respiratoires), de l’exposition résidentielle à l’humidité excessive ou aux moisissures et des covariables (ex. : revenu annuel familial, statut tabagique, atopie familiale, caractéristiques de l’étudiant). Les associations entre cette exposition et ces maladies ont d’abord été examinées par des tests de chi-carré en utilisant un seuil alpha de 0,05. Des régressions logistiques multivariées ont ensuite été utilisées pour déterminer les associations brutes et ajustée entre cette exposition et les maladies respiratoires. Les analyses descriptives ont été pondérées pour le sexe, l’âge et le campus d’étude. RÉSULTATS: L’exposition à l’humidité excessive ou aux moisissures était fréquente parmi les participants (36,0%; Intervalle de confiance (IC)95% : 33,9-38,1). Ceux-ci ont également été nombreux à rapporter une rhinite allergique (23,9%; IC95% :22,0-25,8), de l’asthme (32,6%; IC95% : 30,5-34,7) et des infections respiratoires (19,4%; IC95% :17,7-21,2) au cours de la dernière année. Après ajustement, les associations demeuraient significatives entre l’exposition à l’humidité excessive ou aux moisissures et la rhinite allergique (Rapport de cote (RC) : 1,30; IC95% : 1.05-1.60), l’asthme RC : 1,75; IC95% : 1,42-2,16), mais pas les infections respiratoires (RC : 1,07; IC95% : 0,85-1.35). CONCLUSIONS: La prévalence élevée de l’exposition résidentielle des étudiants universitaires à l’humidité excessive ou aux moisissures, de même que son association avec l’asthme et la rhinite allergique, mettent en lumière sa contribution potentielle à la forte prévalence des maladies respiratoires ayant une composante allergique dans cette population. Cette étude fournit un nouveau levier pour les organisations de santé publique et leurs partenaires afin d’adapter les stratégies préventives ciblant les logements insalubres, particulièrement chez les populations vulnérables.

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The generation of functional, vascularized tissues is a key challenge for the field of tissue engineering. Before clinical implantations of tissue engineered bone constructs can succeed, in vitro fabrication needs to address limitations in large-scale tissue development, including controlled osteogenesis and an inadequate vasculature network to prevent necrosis of large constructs. The tubular perfusion system (TPS) bioreactor is an effective culturing method to augment osteogenic differentiation and maintain viability of human mesenchymal stem cell (hMSC)-seeded scaffolds while they are developed in vitro. To further enhance this process, we developed a novel osteogenic growth factors delivery system for dynamically cultured hMSCs using microparticles encapsulated in three-dimensional alginate scaffolds. In light of this increased differentiation, we characterized the endogenous cytokine distribution throughout the TPS bioreactor. An advantageous effect in the ‘outlet’ portion of the uniaxial growth chamber was discovered due to the system’s downstream circulation and the unique modular aspect of the scaffolds. This unique trait allowed us to carefully tune the differentiation behavior of specific cell populations. We applied the knowledge gained from the growth profile of the TPS bioreactor to culture a high-volume bone composite in a 3D-printed femur mold. This resulted in a tissue engineered bone construct with a volume of 200cm3, a 20-fold increase over previously reported sizes. We demonstrated high viability of the cultured cells throughout the culture period as well as early signs of osteogenic differentiation. Taking one step closer toward a viable implant and minimize tissue necrosis after implantation, we designed a composite construct by coculturing endothelial cells (ECs) and differentiating hMSCs, encouraging prevascularization and anastomosis of the graft with the host vasculature. We discovered the necessity of cell to cell proximity between the two cell types as well as preference for the natural cell binding capabilities of hydrogels like collagen. Notably, the results suggested increased osteogenic and angiogenic potential of the encapsulated cells when dynamically cultured in the TPS bioreactor, suggesting a synergistic effect between coculture and applied shear stress. This work highlights the feasibility of fabricating a high-volume, prevascularized tissue engineered bone construct for the regeneration of a critical size defect.

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The fish meat has a particular chemical composition which gives its high nutritional value. However, this food is identified for being highly perishable and this aspect is often named as a barrier to fish consumption. The southwestern Paraná region, parallel to the country's reality, it is characterized by low fish consumption; and one of the strategies aimed at increasing the consumption of this important protein source is encouraging the production of other species besides tilapia. Within this context, it is necessary to know about the meat characteristics. In this sense, the objective of this study was to evaluate the technological potential of pacu, grass carp and catfish species. To do so, at first, it was discussed the chemical and biometric assessment under two distinct descriptive statistical methods, of the three species; and it was also evaluated the discriminating capacity of the study. In a second moment, an evaluation of effects done by two different processes of washing (acid and alkaline) regarding the removal of nitrogen compounds, pigments and the emulsifying ability of the proteins contained in the protein base obtained. Finally, in the third phase, it was aimed to realize the methodology optimization in GC-MS for the analysis geosmin and MIB (2-metilisoborneol) compounds that are responsible for taste/smell of soil and mold in freshwater fish. The results showed a high protein and low lipid content for the three species. The comparison between means and medians revealed symmetry only for protein values and biometric measurements. Lipids, when evaluated only by the means, overestimate the levels for all species. Correlations between body measurements and fillet yield had low correlation, regardless of the species analyzed, and the best prediction equation relates the total weight and fillet weight. The biometric variables were the best discriminating among the species. The evaluation of the washings, it was found that the acidic and basic processes were equally (p ≥ 0.05) efficient (p ≤ 0.05) for the removal of nitrogen compounds on the fish pulps. Regarding the extraction of pigments, a removal efficiency was recorded only for the pacu species, the data were assessed by the parameters L *, a *, b *. When evaluated by the total color difference (ΔE) before and after washing for both processes (acid/alkaline) the ΔE proved feasible perceived by naked eye for all species. The catfish was characterized as the fish that presents the clearest meat with the basic washing considered the most effective in removing pigments for this species. Protein bases obtained by alkaline washes have higher emulsifying capacity (p ≤ 0.05) when compared to unwashed and washed in acid process pulps. The methodology applied for the quantification of MIB and geosmin, allowed to establish that the method of extraction and purification of analytes had low recovery and future studies should be developed for identification and quantification of MIB and geosmin on fish samples.