Avaliação imunoistoquímica de CD34 e triptase em cistos odontogênicos radiculares e cistos dentígeros inflamados

Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq

Avaliação imunoistoquímica de CD34 e triptase em cistos odontogênicos radiculares e cistos dentígeros inflamados

Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq

Advanced Aerogel Composites for Oil Remediation and Recovery

Oil spills in marine environments often damage marine and coastal life if not remediated rapidly and efficiently. In spite of the strict enforcement of environmental legislations (i.e., Oil Pollution Act 1990) following the Exxon Valdez oil spill (June 1989; the second biggest oil spill in U.S. history), the Macondo well blowout disaster (April 2010) released 18 times more oil. Strikingly, the response methods used to contain and capture spilled oil after both accidents were nearly identical, note that more than two decades separate Exxon Valdez (1989) and Macondo well (2010) accidents.

The goal of this dissertation was to investigate new advanced materials (mechanically strong aerogel composite blankets-Cabot® Thermal Wrap™ (TW) and Aspen Aerogels® Spaceloft® (SL)), and their applications for oil capture and recovery to overcome the current material limitations in oil spill response methods. First, uptake of different solvents and oils were studied to answer the following question: do these blanket aerogel composites have competitive oil uptake compared to state-of-the-art oil sorbents (i.e., polyurethane foam-PUF)? In addition to their competitive mechanical strength (766, 380, 92 kPa for Spaceloft, Thermal Wrap, and PUF, respectively), our results showed that aerogel composites have three critical advantages over PUF: rapid (3-5 min.) and high (more than two times of PUF’s uptake) oil uptake, reusability (over 10 cycles), and oil recoverability (up to 60%) via mechanical extraction. Chemical-specific sorption experiments showed that the dominant uptake mechanism of aerogels is adsorption to the internal surface, with some contribution of absorption into the pore space.

Second, we investigated the potential environmental impacts (energy and chemical burdens) associated with manufacturing, use, and disposal of SL aerogel and PUF to remove the oil (i.e., 1 m3 oil) from a location (i.e., Macondo well). Different use (single and multiple use) and end of life (landfill, incinerator, and waste-to-energy) scenarios were assessed, and our results demonstrated that multiple use, and waste-to-energy choices minimize the energy and material use of SL aerogel. Nevertheless, using SL once and disposing via landfill still offers environmental and cost savings benefits relative to PUF, and so these benefits are preserved irrespective of the oil-spill-response operator choices.

To inform future aerogel manufacture, we investigated the different laboratory-scale aerogel fabrication technologies (rapid supercritical extraction (RSCE), CO2 supercritical extraction (CSCE), alcohol supercritical extraction (ASCE)). Our results from anticipatory LCA for laboratory-scaled aerogel fabrication demonstrated that RSCE method offers lower cumulative energy and ecotoxicity impacts compared to conventional aerogel fabrication methods (CSCE and ASCE).

The final objective of this study was to investigate different surface coating techniques to enhance oil recovery by modifying the existing aerogel surface chemistries to develop chemically responsive materials (switchable hydrophobicity in response to a CO2 stimulus). Our results showed that studied surface coating methods (drop casting, dip coating, and physical vapor deposition) were partially successful to modify surface with CO2 switchable chemical (tributylpentanamidine), likely because of the heterogeneous fiber structure of the aerogel blankets. A possible solution to these non-uniform coatings would be to include switchable chemical as a precursor during the gel preparation to chemically attach the switchable chemical to the pores of the aerogel.

Taken as a whole, the implications of this work are that mechanical deployment and recovery of aerogel composite blankets is a viable oil spill response strategy that can be deployed today. This will ultimately enable better oil uptake without the uptake of water, potential reuse of the collected oil, reduced material and energy burdens compared to competitive sorbents (e.g., PUF), and reduced occupational exposure to oiled sorbents. In addition, sorbent blankets and booms could be deployed in coastal and open-ocean settings, respectively, which was previously impossible.

Reporting on data monitoring committees in neonatal randomised controlled trials is inconsistent

Aim: To evaluate the reported use of Data Monitoring Committees (DMCs), the frequency of interim analysis, pre-specified stopping rules and early trial termination in neonatal randomised controlled trials (RCTs). Methods: We reviewed neonatal RCTs published in four high impact general medical journals, specifically looking at safety issues including documented involvement of a DMC, stated interim analysis, stopping rules and early trial termination. We searched all journal issues over an 11-year period (2003-2013) and recorded predefined parameters on each item for RCTs meeting inclusion criteria. Results: Seventy neonatal trials were identified in four general medical journals: Lancet, New England Journal of Medicine (NEJM), British Medical Journal and Journal of American Medical Association (JAMA). 43 (61.4%) studies reported the presence of a DMC, 36 (51.4%) explicitly mentioned interim analysis; stopping rules were reported in 15 (21.4%) RCTs and 7 (10%) trials were terminated early. The NEJM most frequently reported these parameters compared to the other three journals reviewed. Conclusion: While the majority of neonatal RCTs report on DMC involvement and interim analysis there is still scope for improvement. Clear documentation of safety related issues should be a central component of reporting in neonatal trials involving newborn infants.

Reduced calcification decreases photoprotective capability in the Coccolithophorid Emiliania huxleyi

Intracellular calcification of coccolithophores generates CO2 and consumes additional energy for acquisition of calcium and bicarbonate ions; therefore, it may correlate with photoprotective processes by influencing the energetics. To address this hypothesis, a calcifying Emiliania huxleyi strain (CS-369) was grown semi-continuously at reduced (0.1 mM, LCa) and ambient Ca2+ concentrations (10 mM, HCa) for 150 d (>200 generations). The HCa-grown cells had higher photosynthetic and calcification rates and higher contents of Chl a and carotenoids compared with the naked (bearing no coccoliths) LCa-grown cells. When exposed to stressfull levels of photosynthetically active radiation (PAR), LCa-grown cells displayed lower photochemical yield and less efficient non-photochemical quenching (NPQ). When the LCa- or HCa-grown cells were inversely shifted to their counterpart medium, LCa to HCa transfer increased photosynthetic carbon fixation (P), calcification rate (C), the C/P ratio, NPQ and pigment contents, whereas those shifted from HCa to LCa exhibited the opposite effects. Increased NPQ, carotenoids and quantum yield were clearly linked with increased or sustained calcification in E. huxleyi. The calcification must have played a role in dissipating excessive energy or as an additional drainage of electrons absorbed by the photosynthetic antennae. This phenomenon was further supported by testing two non-calcifying strains, which showed insignificant changes in photosynthetic carbon fixation and NPQ when transferred to LCa conditions

Applying life cycle assessment to analyze the environmental sustainability of public transit modes for the City of Toronto

One challenge related to transit planning is selecting the appropriate mode: bus, light rail transit (LRT), regional express rail (RER), or subway. This project uses data from life cycle assessment to develop a tool to measure energy requirements for different modes of transit, on a per passenger-kilometer basis. For each of the four transit modes listed, a range of energy requirements associated with different vehicle models and manufacturers was developed. The tool demonstrated that there are distinct ranges where specific transit modes are the best choice. Diesel buses are the clear best choice from 7-51 passengers, LRTs make the most sense from 201-427 passengers, and subways are the best choice above 918 passengers. There are a number of other passenger loading ranges where more than one transit mode makes sense; in particular, LRT and RER represent very energy-efficient options for ridership ranging from 200 to 900 passengers. The tool developed in the thesis was used to analyze the Bloor-Danforth subway line in Toronto using estimated ridership for weekday morning peak hours. It was found that ridership across the line is for the most part actually insufficient to justify subways over LRTs or RER. This suggests that extensions to the existing Bloor-Danforth line should consider LRT options, which could service the passenger loads at the ends of the line with far greater energy efficiency. It was also clear that additional destinations along the entire transit line are necessary to increase the per passenger-kilometer energy efficiency, as the current pattern of commuting to downtown leaves much of the system underutilized. It is hoped that the tool developed in this thesis can be used as an additional resource in the transit mode decision-making process for many developing transportation systems, including the transit systems across the GTHA.

Co-production of bio-oil and propylene through the hydrothermal liquefaction of polyhydroxybutyrate producing cyanobacteria

A polyhydroxybutyrate (PHB) producing cyanobacteria was converted through hydrothermal liquefaction (HTL) into propylene and a bio-oil suitable for advanced biofuel production. HTL of model compounds demonstrated that in contrast to proteins and carbohydrates, no synergistic effects were detected when converting PHB in the presence of algae. Subsequently, Synechocystis cf. salina, which had accumulated 7.5wt% PHB was converted via HTL (15% dry weight loading, 340°C). The reaction gave an overall propylene yield of 2.6%, higher than that obtained from the model compounds, in addition to a bio-oil with a low nitrogen content of 4.6%. No propylene was recovered from the alternative non-PHB producing cyanobacterial strains screened, suggesting that PHB is the source of propylene. PHB producing microorganisms could therefore be used as a feedstock for a biorefinery to produce polypropylene and advanced biofuels, with the level of propylene being proportional to the accumulated amount of PHB.

Co-production of bio-oil and propylene through the hydrothermal liquefaction of polyhydroxybutyrate producing cyanobacteria

A polyhydroxybutyrate (PHB) producing cyanobacteria was converted through hydrothermal liquefaction (HTL) into propylene and a bio-oil suitable for advanced biofuel production. HTL of model compounds demonstrated that in contrast to proteins and carbohydrates, no synergistic effects were detected when converting PHB in the presence of algae. Subsequently, Synechocystis cf. salina, which had accumulated 7.5wt% PHB was converted via HTL (15% dry weight loading, 340°C). The reaction gave an overall propylene yield of 2.6%, higher than that obtained from the model compounds, in addition to a bio-oil with a low nitrogen content of 4.6%. No propylene was recovered from the alternative non-PHB producing cyanobacterial strains screened, suggesting that PHB is the source of propylene. PHB producing microorganisms could therefore be used as a feedstock for a biorefinery to produce polypropylene and advanced biofuels, with the level of propylene being proportional to the accumulated amount of PHB.

Gas Solubility and Vapor Pressure of Electrolytes Based on Alkylcarbonates Containing Litfsi, Lifap, and LiPF6 Lithium Salt: Measurement and Prediction

Most liquid electrolytes used in commercial lithium-ion batteries are composed by alkylcarbonate mixture containing lithium salt. The decomposition of these solvents by oxidation or reduction during cycling of the cell, induce generation of gases (CO2, CH4, C2H4, CO …) increasing of pressure in the sealed cell, which causes a safety problem [1]. The prior understanding of parameters, such as structure and nature of salt, temperature pressure, concentration, salting effects and solvation parameters, which influence gas solubility and vapor pressure of electrolytes is required to formulate safer and suitable electrolytes especially at high temperature.

We present in this work the CO2, CH4, C2H4, CO solubility in different pure alkyl-carbonate solvents (PC, DMC, EMC, DEC) and their binary or ternary mixtures as well as the effect of temperature and lithium salt LiX (X = LiPF6, LiTFSI or LiFAP) structure and concentration on these properties. Furthermore, in order to understand parameters that influence the choice of the structure of the solvents and their ability to dissolve gas through the addition of a salt, we firstly analyzed experimentally the transport properties (Self diffusion coefficient (D), fluidity (h-1), and conductivity (s) and lithium transport number (tLi) using the Stock-Einstein, and extended Jones-Dole equations [2]. Furthermore, measured data for the of CO2, C2H4, CH4 and CO solubility in pure alkylcarbonates and their mixtures containing LiPF6; LiFAP; LiTFSI salt, are reported as a function of temperature and concentration in salt. Based on experimental solubility data, the Henry’s law constant of gases in these solvents and electrolytes was then deduced and compared with values predicted by using COSMO-RS methodology within COSMOthermX software. From these results, the molar thermodynamic functions of dissolution such as the standard Gibbs energy, the enthalpy, and the entropy, as well as the mixing enthalpy of the solvents and electrolytes with the gases in its hypothetical liquid state were calculated and discussed [3]. Finally, the analysis of the CO2 solubility variations with the salt addition was then evaluated by determining specific ion parameters Hi by using the Setchenov coefficients in solution. This study showed that the gas solubility is entropy driven and can been influenced by the shape, charge density, and size of the anions in lithium salt.

References

[1] S.A. Freunberger, Y. Chen, Z. Peng, J.M. Griffin, L.J. Hardwick, F. Bardé, P. Novák, P.G. Bruce, Journal of the American Chemical Society 133 (2011) 8040-8047.

[2] P. Porion, Y.R. Dougassa, C. Tessier, L. El Ouatani, J. Jacquemin, M. Anouti, Electrochimica Acta 114 (2013) 95-104.

[3] Y.R. Dougassa, C. Tessier, L. El Ouatani, M. Anouti, J. Jacquemin, The Journal of Chemical Thermodynamics 61 (2013) 32-44.

Techno-Economic and Life Cycle Assessment for the Production of Green Composites

Botanically, green composites belong to an economically important seed plant family that includes maize, wheat, rice, and sorghum known as Saccharum offi cinarum. There are so many natural fibers available in the environment such as rice husk, hemp fibers, flax fibers, bamboo fibers, coconut fiber, coconut coir, grawia optiva and many others also. Life Cycle Assessment (LCA) is a process to estimate the environmental feature and potential impacts related to a product, by organizing a directory of pertinent inputs and outputs of a product system, assessing the potential environmental impacts related with the said inputs and outputs, explaining the results of the inventory analysis and impact evaluation phases in connection to the objectives of the study. Particularly Bagasse, an agricultural residue not only becomes a problem from the environmental point of view, but also affects the profitability of the sugarcane industries. This chapter discusses the properties, processing methods and various other aspects including economic and environmental aspects related to green composites.

La compétence sociale des enfants et des adolescents atteints de déficience motrice cérébrale

Les enfants atteints de déficience motrice cérébrale (DMC) intégrés en milieu scolaire ordinaire vivent davantage de difficultés relatives à la compétence sociale que les autres enfants. En lien avec le modèle SOCIAL de Beauchamp et Anderson (2010) (The socio-cognitive integration of abilities model), deux questions sont abordées afin de comprendre ces difficultés. Dans le premier article, les attributions d’intentions (AI) hostiles sont mesurées par le Home Interview with Child (HIWC), un ensemble de vignettes représentants des situations sociales ambigües. Les résultats montrent que l’acceptation sociale, plus que le statut de naissance, est associé à l’hostilité des AI à 15 ans. Les enfants rejetés et populaires ont un niveau d’AI hostiles supérieur aux enfants de la catégorie d’acceptation sociale moyenne. Il est proposé que l’acceptation sociale soit un médiateur important à considérer dans le développement d’un biais d’AI hostile chez les enfants atteints de DMC. Dans le deuxième article, la dominance sociale (i.e., une forme de leadership) est évaluée dans une situation de résolution de problème en équipe. Les comportements relatifs à la dominance sociale (i.e., les comportements prosociaux et coercitifs) sont codifiés à l’aide d’une grille créée et validée pour cette étude. Les résultats révèlent que, sans égard au score d’acceptation sociale, les enfants atteints de DMC effectuent significativement moins de comportements prosociaux et coercitifs que les enfants sans DMC au cours de la résolution de problème. De plus, leur équipe de travail émet un nombre de comportements prosociaux et coercitifs inférieur à celui observé dans l’équipe des deux enfants témoins. Les difficultés de compétence sociale observées chez les jeunes atteints de DMC pourraient être en partie expliquées par une faible dominance sociale lors d’activités sollicitant les fonctions exécutives. Enfin, les deux articles présentés permettent d’explorer de nouvelles avenues pour comprendre et soutenir le développement de la compétence sociale chez les enfants et les adolescents atteints de DMC. Les interventions auprès de cette clientèle devraient avoir lieu tôt et devraient cibler autant les habiletés motrices de ces jeunes que leur compétence sociale, avant que des signaux clairs ne compromettent déjà leur expérience sociale globale en milieu scolaire ordinaire.

Correlación entre los resultados de valoración funcional y de fuerza de la rodilla en pacientes con rotura del ligamento cruzado anterior

Programa de doctorado: Avances en Traumatología. Medicina del Deporte. Cuidado de Heridas. La fecha de publicación es la fecha de lectura

Un esempio di Economia Circolare: il riciclo e il riuso dei dispositivi Tessili per Sala Operatoria

Negli ultimi decenni l’attenzione alle tematiche della sostenibilità ambientale e dell’inquinamento globale da parte dell’opinione pubblica e delle imprese è in costante aumento. Una tra le principali fonti di inquinamento è costituita dai rifiuti, e di conseguenza, la loro gestione e il loro smaltimento sono diventate una priorità, non solo per le istituzioni, ma anche per le imprese e per i cittadini. Inoltre la crescita della domanda delle risorse presenti in natura è in costante aumento e l’approvvigionamento di esse si è rivelato essere invece soggetto a significativi limiti. In questo attuale contesto quindi, il modello economico lineare fino ad oggi utilizzato, “take-make-dispose”, non risulta più idoneo. Si è sviluppato così il concetto di “Economia Circolare”. L’obiettivo di questa economia è quello di eliminare il concetto di scarto, il rifiuto deve essere considerato una vera e propria risorsa. In questo sistema tutte le attività, a partire dall’ estrazione fino ad arrivare alla produzione, sono organizzate in modo che i rifiuti di uno diventino risorse per un altro. L’obiettivo della tesi è quello di applicare il concetto di Economia Circolare al mercato dei dispositivi tessili per sala operatoria (DTSO), utilizzando la valutazione del ciclo di vita di un prodotto (analisi LCA) in modo da individuare le fasi più critiche e poter operare dei miglioramenti. Dopo essere stati sottoposti a 70 cicli di lavaggio e sterilizzazione i dispositivi TTR (Tessuti Tecnici Riutilizzabili) non sono più idonei ad essere utilizzati in ambito ospedaliero e vengono smaltiti in discarica , così come vengono smaltiti altri miliardi di rifiuti ogni giorno.Questi tessuti, seppur non conformi agli standard qualitativi richiesti dalle norme ospedaliere, possono essere riciclati o riutilizzati in prodotti di altro tipo. L’obiettivo di questo lavoro è quello di reimmettere questi dispositivi in un ciclo di vita di un nuovo prodotto, in ottica appunto di economia circolare.

Biopolttoaineilla kestävyyttä merenkulkuun? Elinkaariarviointi kestävyyden mittarina

Merenkulun ilmapäästöillä on laajoja vaikutuksia sekä ilmanlaatuun, ilmaston-muutokseen että ihmisten terveyteen. Muiden liikennemuotojen päästöihin on puututtu jo pitkään, mutta merenkulun yhteydessä International Maritime Organisation IMO on asettanut rajoituksia mm. rikkipäästöille vasta viime vuosina. Itämeri on saanut erityisaseman ns. SECA-alueena, jolla operoivien alusten polttoaineen rikkipitoisuus ei saa ylittää 0,1 prosenttia. Yhtenä ratkaisuna päästöongelmiin voivat toimia biopolttoaineet. Liikennekäyttöön tarkoitettuja biopolttoaineita on jo kaupallisessa käytössä ja mm. jätepohjaisia raaka-aineita tutkitaan parhaillaan. EU:n biopolttoaineita käsittelevät säädökset edellyttävät, että tuotannon on oltava kestävää, jotta sillä saavutetaan todellisia kasvihuonekaasupäästöjen vähennyksiä. Kestävyyden arviointiin paras keino on elinkaariarviointi eli LCA, jonka avulla voidaan laskennallisesti osoittaa päästövähennykset verrattuna fossiilisen poltto-ainetuotannon ja käytön tuottamiin päästöihin. Elinkaariarviointi ottaa huomioon tuotantoketjun kaikki päästöt aina raaka-aineen tuottamisesta tuotteen hävittämiseen saakka. Tässä tutkimuksessa elinkaariarviointi suoritettiin Turussa sijaitsevan VG-Shipping -varustamon tarpeisiin. Tuloksia käytetään lain edellyttämän toiminnan-harjoittajan kestävyysjärjestelmän luomiseen sekä sen arviointiin, miten elinkaariarviointi toimii kestävyyden mittarina. VG-Shipping tuottaa oman varustamotoimintansa tarpeisiin jätepohjaisista raaka-aineista tuotettua bioöljyä ja -dieseliä. Elinkaariarviointi osoitti tuotannon olevan kestävällä tasolla ja päästövähennysten olevan fossiiliseen vertailukohtaan nähden eri tuotantoketjuilla 84-96 prosentin välillä.

Production économique d’un solvant vert à partir de dioxyde de carbone (CO2)

Depuis que l’industrie chimique vise à rejeter de moins en moins de gaz à effet de serre, cette dernière cherche à revaloriser les différents gaz à effet de serre tel que le dioxyde de carbone. Une des techniques est de combiner le dioxyde de carbone avec de l’ammoniac pour synthétiser l’urée qui pourrait par la suite être utilisé soit directement ou soit comme intermédiaire, pour la synthèse catalytique du diméthyle carbonate (DMC). Le DMC est à la base de plusieurs applications industrielles telles que la synthèse des polymères (les polycarbonates), les réactions de trans-estérification menant à d’autres carbonates comme le diphénylcarbonate et comme agent de méthylation ou d’alkylation. Plusieurs articles provenant de la littérature scientifique rapportent que le DMC peut être utilisé comme additif oxygéné dans les carburants tels l’essence [1]. Le but de ce projet est de déterminer la viabilité industrielle de la production de DMC par la méthylation de l’urée en premier lieu en méthyle carbamate puis en DMC. La première étape de ce projet reposera donc dans un premier temps sur la confirmation des résultats rapportés au sein de la littérature ouverte pour par la suite faire une étude de l’impact des différents types de catalyseurs et des conditions expérimentales sur le rendement de la réaction. Une fois que le montage batch sera optimisé, ce dernier sera modifié pour opérer en continu. Cette modification a pour but d’augmenter le rendement et la sélectivité pour éventuellement de l’adapter industriellement. Selon la littérature, les rendements anticipés pour la réaction batch sont d’environ 30 % [2] et pour un système en continu de plus de 50 %.