Orientador: Eunice Oba / Resumo: A congelação de sêmen é uma ferramenta de grande importância na reprodução de animais domésticos, auxiliando na difusão do do material genético, preservando-o por tempo indeterminado, além do maior aproveitamento do uso de reprodutores com genética superior comprovada. Para que a congelação de sêmen seja eficiente e alcance resultados satisfatórios com a inseminação, utiliza-se no processo o emprego de diluentes, que tem como função proteger a célula contra o choque térmico e manter o espermatozoide viável até o momento da inseminação. O uso de frações de leite como meio diluidor tem se tornado muito conhecida e de grande importância no processo, usando, por exemplo, as micelas de caseína que conferem função de proteção da membrana plasmática e manutenção da viabilidade espermática. Levando em conta essas informações, este trabalho teve como objetivo avaliar a ação do caseinato de sódio nas características seminais pós descongelação do sêmen utilizando diluentes a base de gema de ovo (BB) e o mesmo diluente acrescido de caseinato de sódio 2% (BC).No experimento I, foram colhidos 3 ejaculados de 8 animais (n=24) por eletroejaculação, este sêmen foi divido em duas alíquotas, uma era diluída em meio comercial a base de gema de ovo e a outra alíquota diluída no mesmo meio mas acrescido de 2% de caseinato de sódio, em seguida foram envasadas em palhetas francesas com volume de 0,25 ml e refrigerado 4 horas á 5 °C em seguida congelado em nitrogênio líquido. Após a congelação as amo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The reproduction of domestic animals, helping in the diffusion of the genetic material, preserving it indefinitely, in addition to the greater use of reproducers with proven superior genetics. In order for semen freezing to be efficient and achieve satisfactory results with insemination, the use of diluents is used in the process, which has the function of protecting the cell against thermal shock and keeping the sperm viable until the time of insemination. The use of milk fractions as a diluting medium has become very well known and of great importance in the process, using, for example, the casein micelles that provide a protective function of the plasma membrane and maintenance of sperm viability. Taking this information into account, this study aimed to evaluate the action of sodium caseinate on semen characteristics after semen thawed using egg yolk (BB) diluents and the same diluent plus 2% sodium caseinate (BC) In experiment I, 3 ejaculates were collected from 8 animals (n = 24) by electroejaculation, this semen was divided into two aliquots, one was diluted in commercial medium based on egg yolk and the other diluted in the same medium but added of 2% sodium caseinate, then they were packaged in French straws with a volume of 0.25 ml and refrigerated 4 hours at 5 ° C then frozen in liquid nitrogen. After freezing, the samples were evaluated by computerized analysis of sperm movement (CASA), integrity of plasma and acrosomal membranes and generation of superoxide anion... (Complete abstract click electronic access below) / Mestre

This thesis examines the effects of product composition, reactant temperature, reactant pressure, fuel-air equivalence ratio, diluent addition, and fuel composition on entropy generation in a constant internal energy/constant volume combustion process. Equilibrium product composition is shown to produce less combustion-generated entropy than frozen product composition. Using methane as the fuel, it is found that increasing reactant temperature by 100 K decreases entropy generation by 6 to 9 percent, while reactant pressure has little effect on entropy generation. Total entropy generation is increased with excess air and increased diluent addition. For the three fuels considered in this analysis (CH4, C2H5OH, C8H18), iso-octane uniformly exhibits the highest entropy generation, indicating the strong effect of fuel type and structure on combustiongenerated entropy.

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Densification of tailings slurries to mature fine tailings (MFT) is important in the oil sands industry for tailings inventory reduction, pore water recovery and tailings reclamation. The cause of methane release from the tailings pond of Shell Albian Sands (Albian) and the effects this process has on densification of Albian tailings was investigated. Citrate, added to tailings with polyacrylamide and hydrocarbon-diluent, was identified as the methanogenic substrate. Bacterial and Archaeal 16S rRNA gene sequences in Albian MFT were dominated by matches to Rhodoferax, some Clostridia and sulfate-reducing bacteria, and acetoclastic methanogens. Citrate-, diluent-, and polyacrylamide-amendments to Albian MFT did not cause a microbial shift over a 10-month laboratory incubation period. A potential pathway for microbial methane production in Albian MFT is proposed. Methane production and release from citrate-amended Albian MFT correlated to accelerated densification. Though diluent and polyacrylamide did not affect methanogenesis, they potentially affect gas bubble formation and release. / Microbiology and Biotechnology

The high functionality epoxy resins tetraglycidyl-4,4’-diaminodiphenyl-methane(TGDDM) and triglycidyl-p-aminophenol (TGPAP) are the main components in most aerospace grade epoxy resin formulations. Owing to their high reactivity and high viscosity, TGDDM and TGPAP pose difficulties when used in wet layup composite manufacturing. As such, these resins are often modified to achieve the desired performance both in the liquid and cured states. The main objective of this thesis is to optimise a low viscosity multi-component epoxy resin formulation suitable for use as an aerospace grade composite matrix. The formulation will allow for the addition of high levels of thermoplastic to improve the fracture toughness of the resin whilst also maintaining resin processability. Through the use of thermal analytical techniques this thesis aims to study the effects of varying the TGDDM/TGPAP ratio, incorporation of a low viscosity bi-functional epoxy resin, the diglycidyl ether of bisphenol F (DGEBF) and changes to the stoichiometric ratio (r)between reactive groups of the epoxy resin and amine hardener (4,4’-diaminodiphenylsulphone, DDS) in multi-component epoxy resin formulations. Resin formulations were optimised using factorial experimental design (FED). Results from two FED’s showed curing multi-component resins at a low stoichiometric ratio significantly increased the processing window whilst also increasing the glass transition temperature (Tg) of the cured resin. No apparent benefit could be assigned to the inclusion of TGDDM owing to its poor processability and a Tg similar to TGPAP. Up to 60% DGEBF was incorporated in a multi-component resin formulation whilst still attaining a Tg greater than 220°C. Its inclusion at 60% had the additional benefit of increasing the processing window by 48 minutes over TGPAP, an increase of 62%. Two optimised resin formulations, 100% TGPAP (100T) and a binary mix of 60% DGEBF and 40% TGPAP (60D) were taken forward to study the effects of adding a thermoplastic toughener (polyethersulphone, PES) in incremental amounts up to 50wt%. SEM images showed all toughened 100T resins had a phase separated morphology whilst all 60D resins were homogenous. The phase separation seen in 100T did not improve the matrix fracture toughness when loaded at 10 wt% and 30 wt% PES. Only when 50 wt% PES was added did fracture toughness increase in comparison to the homogenous 60D resins. Through factorial experimental design two epoxy resin formulations which excluded TGDDM were optimised with a low stoichiometric ratio. The optimum aerospace formulation is dependent on the desired processability and fracture toughness of the resin. High DGEBF-containing formulations give the longest processing windows whilst the 100% TGPAP formulation toughened with 50% PES has the highest fracture toughness.

Salamanders are one of the most at-risk taxa in the world due to habitat destruction, pollution, climate change, invasive diseases, and more. This has led to a need for conservation breeding programs that are often associated with zoos and aquaria. Salamanders can be difficult to breed in captivity, though, due to their dependence on specific environmental cues and other unknown factors that stimulate sperm and egg production. To overcome these challenges, assisted reproductive technologies (ART) such as exogenous hormone administration, sperm cryopreservation, and in-vitro fertilization have been developed to increase offspring propagation and maintain genetic diversity. If genetically robust populations of salamander species can be sustainably managed ex situ into the future, then their species can be protected in situ through practices such as reintroductions into native habitats. Given the importance of salamanders to healthy, functioning ecosystems, my doctoral research focused on methods to advance caudate conservation efforts through ART. This dissertation addresses four key areas targeting salamander reproduction for conservation: 1) Novel, non-invasive hormone administration routes; 2) Sperm extender toxicity; 3) Novel sperm cryoprotectants; and 4) Application of ART to target salamander species. The objectives were to: 1) Compare nasal, oral, and intramuscular delivery routes of gonadotropin-releasing hormone on spermic response; 2) Compare sperm extenders at varying osmolalities for maintaining sperm quality over time; 3) Test dimethyl sulfoxide versus dimethylformamide as cryoprotectants to increase frozen-thawed sperm viability, motility, and fertilization capability in the eastern tiger salamander (Ambystoma tigrinum); and 4) Transfer ART protocols developed from the eastern tiger salamander to the eastern hellbender (Cryptobranchus alleganiensis) and spotted salamander (Ambystoma maculatum). This work answers critical questions that should help advance salamander ART research into the future and lead to more sustainably managed caudate populations.

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O objetivo deste estudo foi avaliar a influência de dois aditivos, propionaldehyde (propanal aldeído) e 2,3-butanedione (diquetona diacetil), nas propriedades de comonômeros, copolímeros e resinas compostas à base de Bis-GMA, quando diluído com TEGDMA, Bis-GMA propoxilado (CH3Bis-GMA) e Bis-GMA propoxilado fluorinado (CF3Bis-GMA). Comonômeros, copolímeros e compósitos experimentais foram preparados combinando Bis-GMA com TEGDMA, CH3Bis-GMA, CF3Bis-GMA e, aldeído (24 e/ou 32 mol%) e diquetona (24 e/ou 32 mol%). No caso dos compósitos, partículas híbridas silanizadas (bário aluminosilicato; 60 peso%) foram adicionadas aos comonômeros. Para a fotopolimerização, adicionou-se canforoquinona (0,2 peso%) e N,N-dimetil-p-toluidina (0,2 peso%). Os comonômeros e copolímeros experimentais tiveram as seguintes propriedades avaliadas: viscosidade, contração de polimerização, grau de conversão, ângulo de contato (em esmalte, dentina e vidro), temperatura de transição vítrea (DSC e equação de Fox), microdureza, alteração de rugosidade superficial e desgaste por abrasão. Os compósitos experimentais, tiveram avaliadas as seguintes propriedades: resistência flexural, módulo de elasticidade, tração diametral, módulo de resiliência, microdureza, alteração de rugosidade superficial e desgaste por abrasão. Os sistemas Bis-GMA/TEGDMA e Bis-GMA/CH3Bis-GMA tiveram suas propriedades significantemente alteradas pela incorporação de aditivos (propanal ou diquetona). Os aditivos (propanal/diquetona) não influenciaram de forma significante as propriedades do sistema Bis-GMA/CF3Bis-GMA. O efeito dos aditivos nas propriedades dos materiais analisados relaciona-se à sua abilidade em aumentar o grau de conversão de alguns sistemas resinosos / The purpose of this study was to evaluate the effect of two additives, propionaldehyde (aldehyde) and 2,3-butanedione (diketone), on the properties of Bis-GMA based comonomer, copolymer and composites when diluted with TEGDMA, propoxylated Bis- GMA (CH3Bis-GMA) and propoxylated fluorinated Bis-GMA (CF3Bis-GMA). Experimental comonomer/copolymer/composites were prepared combining Bis-GMA and TEGDMA, CH3Bis-GMA, CF3Bis-GMA, with aldehyde (24 and/or 32 mol%) and diketone (24 and/or 32 mol%). For composites, hybrid treated filler (barium aluminosilicate glass; 60 wt%) was added to monomer mixtures. Photopolymerization was effected by using camphorquinone (0.2 wt%) and N,N-dimethyl-p-toluidine (0.2 wt%). Experimental comonomer/copolymers viscosity, polymerization shrinkage, degree of conversion, contact angle (enamel, dentin and glass surfaces), glass transition temperature (DSC and Fox equation), microhardness, surface roughness changes and wear were evaluated. Experimental composites, flexural strength, modulus of elasticity, diametral tensile strength, modulus of resilience, microhardness, surface roughness changes and wear were also assessed. Bis-GMA/TEGDMA and Bis- GMA/CH3Bis-GMA systems had properties significantly influenced by incorporation of additives (either propanal or diketone). Additives (propanal/diketone) did not significantly influence on Bis-GMA/CF3Bis-GMA system properties. The effect of additives on the evaluated material properties is mainly attributed to their ability in improving some resin systems degree of conversion

Submitted by (edna.saturno@ufrpe.br) on 2016-11-09T12:30:04Z No. of bitstreams: 1 Zoraide Fernandes Coleto.pdf: 876143 bytes, checksum: b13d1564a69ff252704812c9a3bbebcd (MD5) / Made available in DSpace on 2016-11-09T12:30:05Z (GMT). No. of bitstreams: 1 Zoraide Fernandes Coleto.pdf: 876143 bytes, checksum: b13d1564a69ff252704812c9a3bbebcd (MD5) Previous issue date: 2006-03-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Antioxidants act as protective agents of spermatozoa preventing the reactive oxygen species formation and consequent lipidic peroxidation rising the motility and the vigor and avoiding the damage provoked to the DNA. The aiming of this work was to study the effect of different concentrations of vitamin C and Trolox (water soluble analogue of vitamin E) on the viability of dog sperm cells submitted to the cryopreservation process. The Pool with the second semen fraction of four dogs, harvested through digital manipulation was supplemented with vitamin C and Trolox on the concentration of 200 X 106 sperm cells/dose, according to each group: Exp 1: G1= Tris- egg yolk (Control); G2 = Tris-egg yolk + 1200M of vitamin C; G3= Tris-egg yolk + 2400M of vitamin C; G4= Tris-egg yolk + 100M of Trolox e G5= Tris-egg yolk + 200M of Trolox; Exp 2: G1 = Tris-egg yolk (Control); G2 = Tris-egg yolk + vitamin C (1200M); G3 = Tris-egg yolk + Trolox (200M) and G4 = Tris-egg yolk + vitamin C (1200M) + Trolox (200M); Exp 3: G1 = Tris-egg yolk or Kenney (Control); G2 = Tris-egg yolk or Kenney + vitamin C (1200 M); G3= Tris-egg yolk or Kenney + Trolox (200 M); G4= Tris-egg yolk or Kenney + vitamin C (1200 M) + Trolox (200 M). The samples were frozen using two freezing curves (Curve 1 = -0,25oC/min until 5 oC, -15 oC/min until -5 oC, -10 oC/min until –120 oC; Curve 2 = -0,25 oC/min until 5 oC, -20 oC/min until -5 oC, -20 oC/min until –120 oC), being C1 on the 1, 2, and 3 Experiments and C2 on the 3 Experiment. The samples were stored in liquid nitrogen. After thawed, it was obshigher (P<0.05) among Control, vitamin C (1200M) and Trolox (200M) groups. The vigor, motility, acrosomal and DNA integrity, as well as the percentage of sperm cells stained with nitroblue tetrazolium were not different among experimental groups. On the Exp. 2, the spermatic motility after thawing did not differ among the groups or between the two freezing curves. On the C1, the group diluted with vitamin C + Trolox showed more acrosomal integrity, but on the C2 there was no difference among groups. The percentage of intact acrosome from curve 1, did not differ between the control group (G1) and with vitamin C (G2), but were inferior (P < 0,05) than the vitamin C + Trolox (G4), meanwhile in the Curve 2, there was no difference among the groups. Comparing the freezing curves, it was found a difference (P < 0,05) on the percentage of acrosome prevailed from G2 (vitamin C). Big percentages of sperm cells showed no oxidative stress or, when it occurred, it was concentrated in the middle section of the cells. On the Exp. 3, the sperm motility of the group diluted with Tris- egg yolk supplemented with vitamin C + Trolox were higher than the others. Higher percentage of the cells with intact acrosome were observed on the group supplemented with vitamin C + Trolox. Samples diluted with Kenney (no antioxidant) showed higher percentage of intact acrosome than the diluted on the Tris-egg yolk (no antioxidant). It was observed higher percentage of cells (P<0.05) with head and tail showing the formation of formazana ++ on the samples added with Trolox (G3) and diluted with Tris – egg yolk than those diluted in Kenney. It is concluded that vitamin C (1200M) and Trolox (200M) cab be used to freeze dog semen; The addition of vitamin C and Trolox in Tris – egg yolk diluted samples rise the viability of the spermatic cellserved on the Exp.1 that the frozen at -150 oC/min and -10 oC/min on the negative curves; the addition of vitamin C associated with Trolox minimize the deleterious effects of the cryopreservation of semen on the sperm acrosomal integrity on the diluted samples in Tris – egg yolk. / Anti-oxidantes funcionam como agentes protetores dos espermatozóides impedindo a formação de espécies de oxigênio reativo (ROS) e conseqüente peroxidação lipidica, aumentando a motilidade e o vigor espermático, e evitando os danos provocados ao DNA. Objetivou-se com este trabalho estudar o efeito da adição de vitamina C e Trolox na congelação de sêmen de cão da raça Cocker Americano. O Pool da segunda fração do sêmen de quatro cães, colhida através de manipulação peniana, foi diluído e suplementado com vitamina C e Trolox na concentração de 200 x 106 espermatozóides/dose, de acordo com cada grupo. Exp. 1: G1= Tris-gema (Controle); G2= Tris-gema + 1200M de vitamina C ; G3= Tris-gema + 2400M de vitamina C; G4= Tris-gema + 100M de Trolox e G5= Tris-gema + 200M de Trolox; Exp. 2: G1= Tris-gema (Controle); G2= Tris-gema + vitamina C (1200M); G3= Tris-gema + vitamina E (200M); G4= Tris-gema + vitamina C (1200M) + E (200M); Exp. 3: G1= Tris-gema ou Kenney (Controle); G2 = Tris-gema ou Kenney + vitamina C (1200 M); G3= Tris-gema ou Kenney + Trolox (200 M); G4= Tris-gema ou Kenney + vitamina C (1200 M) + Trolox (200 M). As amostras foram congeladas utilizando duas curvas (C1 = -0,25 oC/min até 5 oC, -15 oC/min até -5 oC, -10 oC/min até –120 oC; C2 = -0,25 oC/min até 5 oC, -20 oC/min até -5 oC, -20 oC/min até –120 oC), sendo C1 nos Exp. 1, 2 e 3, e C2 no Exp. 2, e armazenadas em nitrogênio líquido. Após descongelação a 37 oC durante 30 segundos, observou-se no Exp.1, motilidade espermática significativamente superior (P<0,05) nos grupos controle e tratados com vitamina C (1200M) ou Trolox (200M). O vigor, a integridade do acrossoma e do DNA, bem como o percentual de células espermáticas coradas com Nitroblue tetrazolium não diferiram entre os grupos experimentais. No Exp. 2, a motilidade não diferiu entre grupos ou entre curvas de congelação. Na curva C1, o grupo adicionado de vitamina C + Trolox apresentou mais células com acrossomas intactos, enquanto na C2 não houve diferença entre os grupos. O porcentual de acrossomas íntegros da curva 1, não diferiu entre os grupos controle (G1) e com vitamina C (G2), mas foram inferiores (P < 0,05) ao de vitamina C + Trolox (G4), enquanto na curva 2, não houve diferença entre os grupos. Ao se comparar curvas de congelação encontrou-se diferença (P<0,05) no porcentual de acrossomas reagidos do G2 (vitamina C). Grandes porcentuais de espermatozóides apresentaram-se sem estresse oxidativo ou, quando ocorria, concentrava-se na peça intermediária das células. No Exp. 3, a motilidade espermática dos grupos diluídos com Tris-gema e Tris-gema + vitamina C + Trolox foram superiores aos demais grupos. Maior porcentual de células com acrossomas íntegros foi observado no grupo suplementado com vitamina C + Trolox. Amostras diluídas em Kenney (sem anti-oxidante) apresentaram maior porcentual de acrossomas íntegros do que as diluídas em Tris-gema (sem anti-oxidante). Observou-se maior formação de formazana na cabeça e cauda de células diluídas em Tris-gema + Trolox, do que nas diluídas em Kenney. Conclui-se que a vitamina C (1200M) e Trolox (200M de Trolox) podem ser utilizadas para congelação de sêmen de cão; A adição de vitamina C e Trolox em amostras diluídas em Tris-gema aumenta a viabilidade das células espermáticas congeladas a -15 oC/min e -10 oC/min nas curvas negativas; A suplementação de vitamina C + Trolox minimiza os efeitos deletérios da criopreservação do sêmen sobre a integridade do acrossoma espermático de amostras diluídas em Tris-gema.