No description available.

Differential scanning calorimetry (DSC), 13C solid state nuclear magnetic resonance (SSNMR), one- and two-dimensional fourier transform infrared spectroscopes (FT-IR), Gel Permeation Chromatography (GPC) have been used to investigate the miscibility behavior and specific interactions of Poly(3-hydroxybutyrate), (PHB) blending with poly(styrene-co-vinyl phenol), (PS-co-PVPh) through hydrogen bonding complex upon varying the vinyl phenol contents in copolymer. We describe FT-IR spectra reveal that hydrogen bonding between carbonyl and phenol. A miscibility window exists when the vinyl phenol fraction in the copolymer is greater than 20 mol% in the PHB/PS-co-PVPh blend system, as predicted using the Painter¡VColeman association model. The vinyl-terminated benzoxazine (VB-a), which can be polymerized through ring opening polymerization, was synthesized through the Mannich condensation of bisphenol A, formaldehyde, and allylamine. This VB-a monomer was then blending with epoxy resin, followed by thermal curing concurrently, to form epoxy/VB-a copolymers network. To understand the curing kinetics of this epoxy/VB-a copolymer, dynamic differential scanning calorimetry measurements were performed by Kissinger and Flynn-Wall-Osawa methods. The FTIR analyses revealed the presence of thermal curing reactions and hydrogen bonding interaction of epoxy/VB-a copolymers. Meanwhile, the significant enhancement of the ring opening and allyl polymerizations of the epoxy was observed. For these IPNs, DMA and TGA results indicate that the thermal properties increase with the increase of VB-a contents in epoxy/VB-a copolymers.

In today’s progressively urbanised society, there is an increasing need for cost-effective, environmentally sound technologies for the removal of nutrients (carbon, phosphorous, nitrogen) from polluted water. Nitrogen removal from wastewater is the focus of this thesis. Conventional nitrogen removal requires the two processes of aerobic nitrification followed by anoxic denitrification, which is driven by remaining reducing power. While most wastewaters contain a significant fraction of reducing power in the form of organic substrate, it is difficult to preserve the reducing power required for denitrification, due to the necessary preceding aerobic oxidation step. Consequently, one of the major limitations to complete N-removal in traditional wastewater treatment systems is the shortage of organic carbon substrate for the reduction of oxidised nitrogen (NO2-, NO3-), produced from nitrification. This thesis followed two main research themes that aimed to address the problem of organic carbon limitation in nitrogen removal from wastewater, by management of the oxygen supply. The first theme was the study of N-removal by simultaneous nitrification and denitrification (SND) in the novel reactor type, the sequencing batch reactor (SBR). It was aimed to increase understanding of PHB metabolism and the limiting factors of SND and then to develop a suitable on-line control strategy to manage the oxygen supply and optimise nitrogen removal by SND. The second main research theme was the application of the CANON(Completely Autotrophic Nitrogen-removal Over Nitrite) process for nitrogen removal from wastewater; a novel process that requires minimal oxygen supply and has the potential to completely circumvent the requirement for organic substrate in nitrogen removal because it is catalysed by autotrophic microorganisms – Anammox (anaerobic ammonium oxidisers) and aerobic nitrifiers. For study of the SND process, a completely automated 2 L sequencing batch reactor was developed with on-line monitoring of the dissolved oxygen concentration, pH and oxidation-reduction (ORP) potential. The SBR was operated continuously for up to 2 years and, due to its separation of different phases by time, enabled the study and optimisation of different microbial activities, including acetate uptake and conversion to PHB (feast phase), PHB hydrolysis and consumption (famine phase), nitrification and denitrification (and SND). All experimental work was performed using a mixed culture Project summary and acetate as the organic substrate. Acetate consumption and PHB production was studied under different oxygen supply rates to establish conditions that allow maximum conversion of acetate to PHB during the feast phase. Lower DO supply rates (kLa 6 – 16 h-1) resulted in preservation of a higher proportion of acetate as PHB than at higher DO supply rates (kLa 30 and 51 h-1). Up to 77 % of the reducing equivalents available from acetate were converted to PHB under O2-limitation, as opposed to only 54 % under O2-excess conditions, where a higher fraction of acetate was used for biomass growth. A metabolic model based on biochemical stoichiometry was developed that could reproduce the trends of the effect of oxygen on PHB production. Experimental findings and simulated results highlighted the importance of oxygen control during the feast phase of an SBR in preserving reducing power as PHB. To develop an oxygen management strategy for the aerobic famine phase,the effect of the dissolved oxygen (DO) concentration on SND, using PHB as the electron donor, was investigated. There was a clear compromise between the rate and the percentage of SND achieved at different DO concentrations. A DO setpoint of 1 mg L-1 was optimal for both the percentage of SND (61 %) and rate of SND (4.4 mmol N. Cmol X-1. h-1). Electron flux analysis showed that most SND activity occurred during the first hour of the aerobic famine period, when the oxygen uptake rate (due to NH4 + and PHB oxidation) was highest. Aerated denitrification ceased as soon as NH4 + was depleted. The presence of NH4 + provided an oxygen “shield”, preventing excessive penetration of oxygen into the flocs and creating larger anoxic zones for SND. PHB degradation was first order with respect to the biomass PHB concentration (dfPHB/dt = 0.19 . fPHB). The slow nature of PHB degradation made it a suitable substrate for SND, as it was degraded at a similar rate to ammonium oxidation. While DO control during the aerobic famine phase could increase nitrogen removal via SND, total N-removal in the SBR was still limited by the availability of reducing power(PHB) in the anoxic phase. The length of the aerobic phase needed to be minimised to prevent over-oxidation of PHB after NH4 + depletion. The specific oxygen uptake rate (SOUR) was found to be an effective on-line parameter that could reproducibly detect the end-point of nitrification. A simple method was developed for continuous, on-line measurement of the SOUR, which was used for automated adjustment of the aerobic phase length. Minimisation of the aerobic phase length by feedback control of the Project summary SOUR improved nitrogen removal from 69 % (without phase length control) to 86 %, during one cycle. The SOUR-aeration control technique could successfully adapt the aerobic phase length to varying wastewater types and strengths and to varying aeration conditions. The medium- and long-term effects of oxygen management on nitrogen removal was investigated by operating the SBR continuously for up to one month using DO control throughout all stages of the SBR, i.e. oxygen-limitation during the feast phase, a DO setpoint of 1 mg L-1 during the famine phase and SOUR controlled aerobic phase length. Complete oxygen management resulted in minimisation of the amount of PHB that was oxidised aerobically in each SBR cycle and caused an accumulation of cellular PHB over time. The increased availability of PHB during aeration resulted in a higher SOUR and increased N-removal by SND from 34 to 54 %. After one month of continuous SBR operation, the settling efficiency of the biomass improved from 110 mL . g-1X to less than 70 mL . g-1X and almost complete N-removal (9 %) was achieved via SND during aeration, however at a reduced rate (1.5 mmol Cmol X-1 h-1). Therefore, long-term oxygen management resulted in biomass with improved settling characteristics and a higher capacity for SND. Results of the first main research theme highlighted the importance of aeration control throughout all stages of the SBR for maximum N-removal via SND. The CANON process was investigated as an alternative to the use of conventional activated sludge for treatment of wastewaters limited by organic carbon substrate. The initial study of the CANON process was performed at the Kluyver Laboratory in Delft, the Netherlands, using an already established Anammox enrichment culture. The effect of extended periods of NH4 +-limitation on the CANON microbial populations was studied, to examine their ability to recover from major disturbances in feed composition. The CANON process was stable for long periods of time until the N-loading rate reached below 0.1 kg N m 3 day-1, when a third population of bacteria developed in the system (aerobic nitrite oxidisers), resulting in a decrease in N-removal from 92 % to 57 %. Nitrite oxidisers developed due to increased levels of oxygen and nitrite. This highlighted the requirement for oxygen control during the CANON process to prevent increased DO levels and growth of undesired microbes. To initiate the CANON process from a local source, Anammox was enriched from local activated sludge (Perth, Western Australia). FISH analysis (fluorescence in situ hybridisation) of the enriched Anammox strain showed that it belonged to the Order Planctomycetales, Project summary the same as all other identified Anammox strains, but represented a new species of Anammox. The enrichment culture was not inhibited by repeated exposure to oxygen, allowing initiation of an intermittently-aerated CANON process to achieve sustained, completely autotrophic ammonium removal (0.08 kg N m-3 day-1) for an extended period of time, without any addition of organic carbon substrate. Dissolved oxygen control played a critical role in achieving alternating aerobic and anaerobic ammonium oxidation. The main conclusion drawn from the study is the important role of oxygen management in achieving improved nitrogen removal. A careful oxygen management strategy can minimise wastage of reducing power to improve PHB-driven SND by activated sludge and can prevent major disturbances to the population balance in the CANON system. Oxygen management has the potential to reduce aeration costs while significantly improving nitrogen removal from wastewaters limited by organic carbon.

Made available in DSpace on 2014-06-11T19:25:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-25Bitstream added on 2014-06-13T19:53:25Z : No. of bitstreams: 1 fuzarijunior_gc_me_ilha.pdf: 1800316 bytes, checksum: 6ffbd14d47f4e72c963f316d2bd14074 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Filmes de PHB puro e de blendas de PHB com borracha natural foram obtidos por prensagem a quente e por “casting” e foram avaliados segundo as propriedades morfológicas, estruturais, térmicas e mecânicas, além de sua suscetibilidade à biodegradação. As blendas mostraram-se imiscíveis. Verificou-se que o processamento e a presença de borracha provocaram mudanças na configuração cristalina do PHB. A presença de borracha aumentou o grau de cristalização do PHB. Filmes tratados termicamente entre 60 e 70oC, apresentaram menor grau de cristalinidade, os quais permanecem estáveis quando resfriados à temperatura ambiente. O processamento por prensagem garantiu certa estabilidade ao filme de PHB puro em relação à degradação isotérmica, por ocasionar a compactação das cadeias poliméricas, compactação essa que é influenciada pela presença de borracha. Para a degradação não isotérmica, um maior conteúdo de borracha elevou a temperatura de degradação efetiva. O aumento de borracha na blenda também ocasionou maior deformação das blendas, com decréscimo de rigidez. O processamento por prensagem garantiu uma maior deformação para filmes de PHB puro em relação ao processamento por casting, entretanto para blendas com grande quantidade de borracha o efeito mostrou-se contrário. Análises de biodegradação em solo mostraram um material potencialmente biodegradável, sendo que a presença de borracha não atrapalhou o ataque microbiano / Pure PHB films and blends of PHB and natural rubber (in films form), were obtained by hot pressing and by casting and its morphological, structural, thermal and mechanical properties were studied using appropriated techniques. The susceptibility to the biodegradation was also analyzed. The blends did not show miscibility and crystallization degree of PHB in the blend showed to be dependent of rubber content and also film processing. Lower degree of crystallization was observed on films treated in the temperature range of 60oC to 70oC. This crystallization remains stable when the temperature drops to room temperature. Pure PHB films obtained by hot pressing showed stability regards to the isothermal degradation due to the polymer chain compaction, which is influenced by the rubber inclusion. The temperature degradation was increased as the rubber content was increased. The increasing content of rubber in the blend films also provide higher deformation with decreasing of stiff. Pure PHB films obtained by hot pressing showed higher deformation then those obtained by casting. However, for blend films with high rubber content, the effect was observed in the other way around. Furthermore, biodegradation analyzes in soil showed that the material is biodegradable and the rubber inclusion does not disturb the microbial attack

Made available in DSpace on 2014-06-12T23:17:14Z (GMT). No. of bitstreams: 2 arquivo9150_1.pdf: 1264743 bytes, checksum: 2fd32c26b44f2c0109e0b16f365b063c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / O poli(hidroxibutirato), PHB, é um poliéster termoplástico sintetizado por vários tipos de bactérias. O PHB é de especial interesse na fabricação de utensílios médicos esterilizáveis por radiação gama, devido às características extraordinárias como sua grande biocompatibilidade e biodegradabilidade. Entretanto, radiação ionizante causa cisões na cadeia principal do PHB, reduzindo sua massa molecular. Destarte, o escopo deste estudo foi investigar a estabilização radiolítica na estrutura e propriedades do PHB nacional, por meio de aditivos comerciais utilizados na estabilização foto e termo-oxidativa de polímeros convencionais. Inicialmente, foram preparados filmes contendo cinco aditivos diferentes, na concentração de 0,5% da massa total do sistema polimérico. Os filmes foram irradiados com dose de 25 kGy e as mudanças na massa molecular viscosimétrica média (Mv) foram analisadas para a seleção do melhor aditivo. Dentre os aditivos testados, um designado aditivo E, do tipo antioxidante, proporcionou uma ótima radio-estabilização. O estabilizante escolhido foi estudado com mais detalhes. Novas amostras de filmes poliméricos foram preparadas com o aditivo E, cujas concentrações (%m/m) foram 0,3; 0,5; 0,7 e 1,0. Neste caso, os filmes foram submetidos a doses de irradiação que variaram de 15 a 50 kGy. Análises viscosimétricas foram realizadas com o propósito de avaliar cisões na cadeia principal induzidas pela radiação. O valor G (cisões/100 eV de energia transferida ao sistema) também foi obtido por técnica de viscosidade. O aditivo E, na concentração de 0,5% (m/m), promoveu uma redução no valor G de 8,6 para 1,5 no intervalo de dose de 0-35 kGy. As demais análises foram todas realizadas com filmes de PHB contendo o aditivo E na concentração de 0,5% (m/m). Análises espectroscópicas (FT-IR, RMN (1H)) mostraram que o aditivo E não modifica a estrutura do PHB. A análise de difração de raios-X mostrou que o aditivo E não influencia na cristalinidade do PHB. Também foi verificado que o grau de cristalinidade dos filmes permaneceu praticamente constante com a irradiação gama. Foi constatado por meio do teste de biodegradação aeróbia que o aditivo E reduz a biodegradabilidade dos filmes de PHB. Provavelmente, a presença do aditivo no sistema polimérico inibiu o metabolismo microbiano

This diploma thesis is focused on the development of organic UV filters. Organic UV filters were extracted from natural resources and encapsulated into nanomaterial-like delivery systems such as liposomes and nanofibres. SPF of particular extracts and carriers with encapsulated extracts were measured. All of the prepared extracts as well as carriers were characterised for their content of natural substances like phenolic compounds and their antioxidant acitvity, stability, cytotoxicity, micriobial acitivity and their safety were studied too. All of the prepared materials were evaluated as suitable for use in comestic industry. However, in a future, it would be appropriate to add to the study other experimental methods to increase the active substances and at the same time increase the SPF protection factor.

Os polímeros são usados em numerosas aplicações e em diferentes segmentos industriais, gerando enormes quantidades de rejeitos no meio ambiente. Entre os vários componentes de resíduos nos aterros sanitários estão os materiais poliméricos, entre eles o Polipropileno que contribuem com 20 a 30% do volume total de resíduos sólidos. Como os materiais poliméricos são imunes à degradação microbiana, permanecem no solo e nos aterros sanitários como um resíduo semipermanente. A preocupação ambiental no sentido de redução de resíduos se voltou para o desenvolvimento de polímeros renováveis para a fabricação de materiais que se decompõem na natureza, entre eles estão às espumas poliméricas biodegradáveis. Os polímeros espumados são considerados materiais do futuro, com um leque abrangente de aplicações; as espumas estruturais, de alta densidade, são usadas principalmente na construção civil, em substituição a metais, madeiras e concreto com a finalidade básica de reduzir custos com materiais. O objetivo deste trabalho foi a incorporação de blendas da matriz polimérica PP/HMSPP com bagaço de cana-de-açúcar, PHB e PLA, na produção de espumas estruturais. A degradação via tratamento térmico, nas temperaturas 100º, 120º e 160º C não foi suficiente para induzir a biodegradabilidade; já a degradação via irradiação gama, nas doses 50, 100, 150, 200 e 500 kGy se mostrou eficaz para indução da biodegradabilidade. As composições com bagaço, irradiadas, também sofreram deterioração superficial, favorecendo a absorção de água, e, consequentemente, uma maior biodegradação. / Polymers are used in various applications and in different industrial areas providing enormous quantities of wastes in environment. Among diverse components of residues in landfills are polymeric materials, including Polypropylene, which contribute with 20 to 30% of total volume of solid residues. As polymeric materials are immune to microbial degradation, they remain in soil and in landfills as a semi-permanent residue. Environmental concerning in litter reduction is being directed to renewable polymers development for manufacturing of polymeric foams. Foamed polymers are considered future materials, with a wide range of applications; high density structural foams are specially used in civil construction, in replacement of metals, woods and concrete with a final purpose of reducing materials costs. At present development, it was possible the incorporation of PP/HMSPP polymeric matrix blends with sugarcane bagasse, PHB and PLA, in structural foams production. Thermal degradation at 100, 120 and 160°C temperatures was not enough to induce biodegradability. Gamma irradiation degradation, at 50, 100, 150, 200 and 500 kGy showed effective for biodegradability induction. Irradiated bagasse blends suffered surface erosion, in favor of water uptake and consequently, a higher biodegradation in bulk structure.

A Inseminação Artificial (IA) é a biotécnica que proporciona a maior pressão de seleção no melhoramento genético de um rebanho e, portanto deveria ser imprescindível na pecuária moderna. A ineficiência na detecção de estro e a baixa ciclicidade ovariana no período pós-parto constituem um grande entrave na aplicabilidade de programas de IA. Frente a estas dificuldades, o uso da Inseminação Artificial em Tempo Fixo (IATF) vem incrementando os resultados obtidos, uma vez que elimina a necessidade de observação de estro e induz a ciclicidade de vacas em anestro pós-parto. Nos protocolos de IATF é de fundamental importância o uso dos dispositivos intravaginais para liberação de progesterona (P4). No mercado atual, estes dispositivos importados são fabricados à base de silicone, um polímero biocompatível, porém não biodegradável. Recentemente, dispositivos intravaginais de P4, incorporada à matriz polimérica biodegradável de poli-hidroxibutirato (PHB), vêm sendo estudados. Este trabalho teve como objetivo comparar a eficiência, em programa de IATF, de um novo dispositivo intravaginal (Progestar®), na taxa de prenhez, em bovinos da raça Nelore, com a do dispositivo à base de silicone, DIB®, atualmente disponível no mercado brasileiro. Foram utilizadas 240 vacas da raça Nelore, em um delineamento de blocos casualizados generalizados, divididas em dois grupos (controle - DIB® e tratamento - Progestar®, usados nos protocolos de sincronização e IATF). Foram realizados 2 experimentos distintos: no primeiro experimento utilizaram-se dispositivos de 1º uso (n=136), enquanto que no segundo experimento, dispositivos de 2º uso (n=104). As taxas de prenhez, decorrentes da IATF (TPIATF) e ao final da estação de monta (TPEM) (variáveis dependentes), foram comparadas por análise de variância, separando o efeito de tratamento, dos blocos e das interações. No experimento 1: não houve interação das variáveis com o tratamento; não houve efeito de tratamento sobre a TPIATF (DIB® - 66,7% e Progestar® - 65,8%) nem sobre a TPEM (DIB® - 95% e Progestar® - 94,7%); houve interação entre período pós-parto (PPP) e escore de condição corporal (ECC). Animais no PPP1 (45 a 70 dias) e ECC4 apresentaram resultados inferiores na TPIATF em relação aos animais ECC5 e 6; houve também interação entre PPP e escore de condição ovariana (ECO), em que animais no PPP2 (71 a 90 dias) que não estavam ciclando apresentaram resultados inferiores de TPIATF, em relação aos animais ciclando; e também não houve efeito das demais variáveis sobre a TPIATF e TPEM. No experimento 2: não houve interação das variáveis com o tratamento; não houve efeito de tratamento sobre a TPIATF (DIB® 2 - 61,6% e Progestar® 2 - 55,8%) nem sobre a TPEM (DIB® 2 - 94,2% e Progestar® 2 - 88,5%); houve interação entre categoria animal (Cat) e PPP, em que primíparas no PPP1 (32 a 55 dias) apresentaram resultados inferiores na TPEM em relação às primíparas no PPP2 (56 a 90 dias); houve também interação entre PPP e ECC, em que animais no PPP2 e com ECC4 apresentaram resultados inferiores de TPEM, em relação aos animais com ECC5; e também houve efeito negativo do PPP1 sobre a TPIATF e de um dos touros na TPEM. Após a realização do experimento concluiu-se que o Progestar® possui semelhante eficiência na taxa de prenhez, quando comparado ao DIB® e que ambos tratamentos têm potencial para proporcionar TPIATF acima de 50% e TPEM acima de 90%. / The artificial insemination (AI) is a biotechnique that causes the fastest genetic improvement of a herd and, therefore should be essential in the modern livestock. Heat detection inefficiency and low ovarian ciclicity in the postpartum period establish a great obstacle on applicability of AI programs. In front of these difficulties, the use of timed artificial insemination (TAI) improves the results, because eliminates the heat detection and induces the ciclicity of cows in anestrous postpartum. In TAI protocols is fundamental the use of intravaginal devices for releasing progesterone (P4). In the current market, these devices are imported and made of silicone, a biocompatible polymer, but not biodegradable. Recently intravaginal progesterone devices made of PHB, a biodegradable polymer, have been studied. The aim of this study was to compare the efficiency, in TAI program, of a new intravaginal device (Progestar®), on pregnancy rate, in Nelore cows, with a device made of silicone DIB®, currently available in the brazilian market. Were used 240 Nelore cows, in a generalized randomized block design, divided in two groups (control - DIB® and treatment - Progestar®, used in the synchronization protocols and TAI). Two experiments were done: the first experiment used new intravaginal devices (n=136), while the second experiment utilized used intravaginal devices (n=104). The pregnancy rates, of TAI (TAIPR) and breeding season (BSPR) (dependent variables), were compared by analysis of variance, separating the treatment, blocks and interactions effect. In experiment 1: there was no interaction between variables and treatment; there was no effect of treatment on TAIPR (DIB® - 66,7% and Progestar® - 65,8%) and on BSPR (DIB® - 95% and Progestar® - 94,7%); there was an interaction between postpartum period (PPP) and body condition score (BCS), in which animals in PPP1 (45 to 70 days) and BCS4 showed inferior results on TAIPR related to animals BCS5 and 6; there was also an interaction between PPP and ovary condition score (OCS), in which animals in PPP2 (71 to 90 days) not cyclic showed inferior results on TAIPR, related to cyclic animals; and there was also no effect of variables on TAIPR and BSPR. In experiment 2: there was no interaction between variables and treatment; there was no effect of treatment on TAIPR (DIB® 2 - 61,6% and Progestar® 2 - 55,8%) and on BSPR (DIB® 2 - 94,2% and Progestar® 2 - 88,5%); there was an interaction between animal category (Cat) and PPP, in which primiparous in PPP1 (32 to 55 days) showed inferior results on BSPR, related to primiparous in PPP2 (56 to 90 days); there was also an interaction between PPP and BCS, in which animals in PPP2 and BCS4 showed inferior results on BSPR, related animals BCS5; and there was also negative effect of PPP1 on TAIPR and one of the bulls on BSPR. This experiment showed that the Progestar® had the same efficiency on pregnancy rate, as the commercially available DIB® and both treatments have the potential to provide TAIPR above 50% and BSPR above 90%.

Dentre os inúmeros fatores para o sucesso dos programas de TE, as receptoras merecem grande destaque por serem fator determinante no sucesso desta biotecnologia. Atualmente, os produtos de liberação de progesterona disponíveis no mercado brasileiro são importados e confeccionados a base de nylon e silicone. O silicone é uma matriz biocompatível, mas não biodegradável, contrariamente aos novos dispositivos que utilizam biopolímeros obtidos a partir da fermentação bacteriana da cana-de-açúcar. O presente experimento tem como objetivo estudar a eficiência do novo dispositivo intravaginal de liberação sustentada de progesterona no programa de TETF, em novilhas e vacas cruzadas, pela avaliação das taxas de aproveitamento, concepção e de prenhez. O experimento foi realizado em parceria com a empresa de Embryo-sys®, a qual foi responsável por realizar a sincronização das receptoras, assim como das inovulações. As sincronizações e as inovulações foram realizadas em três propriedades nos municípios de Paranapanema-SP, Itapetininga-SP e Ouro Fino-MG. Todos os animais foram submetidos a rigoroso manejo sanitário e ginecológico, e mantidos a pasto (Brachiaria decumbens) com suplementação mineral e água ad libitum. As receptoras (n = 205) foram agrupadas equitativamente quanto ao escore de condição corporal, condição ovariana, categoria animal e período pós-parto, em dois grupos: Grupo Controle - dispositivo auricular (Crestar®, Intervet, Holanda) contendo 3mg de norgestomet (n=103) e Grupo Tratado - implante intravaginal (Progestar®, Innovare, Brasil) contendo 1,72g de progesterona (n=102). No início da sincronização ambos os grupos foram tratados com 2mg de benzoato de estradiol (BE, Innovare, Brasil) intramuscular (IM). Os dispositivos permaneceram nos animais por oito dias, e no momento da retirada foram administradas 400UI de eCG (Novormon®, Syntex, Argentina) IM e 530&mu;g cloprostenol sódico (Sincrocio®,Ouro Fino, Brasil) IM. Após 24 horas da retirada, foi aplicado 1mg de BE IM, como indutor de ovulação. Analisando as novilhas (n=77), vacas solteiras (n=69) e paridas (n=59), obtiveram-se os seguintes resultados, respectivamente para os grupos controle e tratamento: taxa de aproveitamento (TA) 72,8% (n=103) vs 83,3% (n=102), de concepção (TC) 47,9% (n=73) vs 42,7% (n=82) e de prenhez (TP) 34,7% (n=101) vs 35,0% (n=100). Em analise posterior, as vacas paridas foram divididas em duas classes de período pós-parto: PP1 de 2 a 4 meses (n=35) e PP2 de 4 a 8 meses (n=24). Houve efeito da interação entre PP e condição ovariana (CO) para a variável TA, obtendo no PP2, os valores, significativamente diferentes (P<0,05), foram de 83,3% para as que estavam ciclando e 50% para as que não estavam ciclando. Também houve efeito de período pós-parto para TC e os valores de PP1 foi de 48,5% e no PP2 foi de 35,3% (P<0,05). Assim como para TC, houve efeito de PP para TP: vacas no PP1 tiveram 45,7% de prenhez, enquanto as que estavam no PP2, 26,4% (P<0,05). Concluiu-se que o novo dispositivo à base de biopolímeros Progestar® foi capaz de proporcionar taxas de ovulação, de concepção e de prenhez nas inovulações em programas TETF, em novilhas e vacas cruzadas, tanto quanto dispositivos confeccionados com silicone que liberam progestágenos (Crestar®). / There are many factors for the successful of ET programs, and the recipients are the major factor on this biotechnique. Nowadays, the products available in the brazilian market for releasing progesterone are imported and made of silicone, a biocompatible polymer, but not biodegradable. Recently, intravaginal progesterone devices made of PHB, a biodegradable polymer made from bacteria fermentation of sugar cane, have been studied. The objective of this present study was to compare the efficiency in ET programs of a new intravaginal device on ovulation, conception and pregnancy rate, in croosbreed heifers and cows, with a device made of silicone Crestar®, currently available in the brazilian market. The experiment was done with help of Embryo-sys® Company, which was responsible for the recipient\'s synchronizations and inovulations. The synchronizations and inovulations were done in three different places: Paranapanema-SP, Itapetininga-SP and Ouro Fino-MG. All the animals were kept in pasture of Brachiaria decumbens with mineral supplementation and ad libitum water. The body and ovary condition score, postpartum period and animal category were utilized for equal division of recipients (n=205), in two groups: control - auricular device (Crestar®) with 3mg of norgestomet (n=103) and treatment - intravaginal device (Progestar®) with 1.72g of progesterone (n=102). On day 0, all the animals received 2mg of estradiol benzoate (IM). On day 8, the devices were removed, 400UI of eCG and 500&mu;g of PGF2&alpha; were injected (IM). After 24 hours, was injected 1mg of estradiol benzoate (IM), as ovulation inductor. The animals had the following results, respectively for control and treatment group: ovulation rate (OR) - 72.8% (n=103) vs 83.3% (n=102), conception rate (CR) - 47.9% (n=73) vs 42.7% (n=82) and pregnancy rate (PR) - 34.7% (n=101) vs 35.0% (n=100). In further analysis, postpartum cows were divided in two classes: PP1 (2 - 4 months, n=35) and PP2 (4 - 8 months, n=24). There was an interaction between PP and ovary condition (OC) on OR, in which animals in PP2 and cyclic showed better results (83.3%) than the animals not cyclic (50%). There was effect of PP on CR, and the values for PP1 and PP2 were 48.5% and 35.5%, respectively. There was also effect of PP on PR: cows in PP1 showed 45.7% of PR, while cows in PP2, 26.4%. This experiment showed that the new intravaginal device (Progestar®) had the same efficiency on ovulation, conception and pregnancy rate, in ET programs, in crossbreed heifers and cows, as the commercially available device Crestar®.

O lixo urbano tem sido apontado como um dos maiores poluentes ambientais. O lixo plástico chega a representar 20% do volume do lixo doméstico. Como alternativa aos plásticos petroquímicos, produtos plásticos menos agressivos ao meio ambiente e mais biodegradáveis têm sido estudados, entre eles os polihidroxialcanoatos (PHA). Os PHA são poliésteres biodegradáveis acumulados como material de reserva por inúmeras bactérias e que possuem aplicabilidade comercial bastante abrangente. Recentemente, os actinomicetos passaram a ser estudados para a produção destes polímeros. Em trabalho prévio, 53 novas linhagens de actinomicetos produtoras de biopolímeros foram isoladas de solo. Neste trabalho foi feita a seleção das bactérias quanto aos polímeros produzidos em diferentes de carbono. Das quatro linhagens selecionadas, duas foram analisadas quanto à produção de um novo polímero. Nas outras duas linhagens foram amplificados e estudados os genes sintetizadores dos polímeros. Em todas as linhagens foram feitas análises taxonômicas e cultivos em rejeitos industriais. / The urban waste has been described as one of the largest environmental pollutants. The plastic garbage can represent up to 20% of the volume of household waste. As an alternative to petrochemical plastics, plastic products less damaging to the environment and more biodegradable have been studied, among them polyhydroxyalkanoates (PHA). The PHA is a biodegradable polyester material accumulated as a reserve material by many bacteria and they have very broad commercial applicability. Recently, the actinomycetes have been studied for the production of polymers. In previous work, 53 new strains of actinomycetes producers of polymers were isolated from soil. In this work the bacterial the selection of bacteria was made concerning the polymers production on different carbon. Of the four strains selected, two were analyzed for the production of a new polymer. In the other two strains were amplified and studied the genes of polymers synthases. In all lineages were analyzed taxonomically and in cultivation on industrial waste.