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The litter deposited on the soil surface at various stages of decomposition is important for primary productivity that impacts the microbial communities and soil carbon storage. The objective of this study was to evaluate the accumulation and decomposition of cultural residues of Theobroma grandiflorum (Willd. ex. Spreng) Schum, Paullinia cupana (Mart.) Ducke, Bixa orellana L., and forest in the Amazon region. The study was carried out in the São Francisco settlement, Canutama in the south of Amazonas, in a randomized block experimental design, and the treatments consisted of four areas with different crops: 1 - P. cupana; 2 - T. grandiflorum; 3 - B. orellana; 4 - Native woodland area (forest), in time subdivided plots: 7, 15, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, and 330 days after the distribution of the bags in the field, all with four repetitions. To evaluate the contribution and fractions of litter, conical collectors were used in each area, and collections were performed monthly in the period from March 2020 to February 2021. The estimate of the decomposition rate of the litter was done by quantifying the loss of mass, using litter bags, which allow for a direct analysis of the rate of decay over time. The forest and P. cupana environments presented the highest litter production, and greater deposition when compared to environments cultivated with T. grandiflorum and B. orellana. The forest and B. orellana areas showed the highest speed of decomposition, while the opposite situation occurred under T. grandiflorum and P. cupana cultivation.

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The litter deposited on the soil surface at various stages of decomposition is important for primary productivity that impacts the microbial communities and soil carbon storage. The objective of this study was to evaluate the accumulation and decomposition of cultural residues of Theobroma grandiflorum (Willd. ex. Spreng) Schum, Paullinia cupana (Mart.) Ducke, Bixa orellana L., and forest in the Amazon region. The study was carried out in the São Francisco settlement, Canutama in the south of Amazonas, in a randomized block experimental design, and the treatments consisted of four areas with different crops: 1 - P. cupana; 2 - T. grandiflorum; 3 - B. orellana; 4 - Native woodland area (forest), in time subdivided plots: 7, 15, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, and 330 days after the distribution of the bags in the field, all with four repetitions. To evaluate the contribution and fractions of litter, conical collectors were used in each area, and collections were performed monthly in the period from March 2020 to February 2021. The estimate of the decomposition rate of the litter was done by quantifying the loss of mass, using litter bags, which allow for a direct analysis of the rate of decay over time. The forest and P. cupana environments presented the highest litter production, and greater deposition when compared to environments cultivated with T. grandiflorum and B. orellana. The forest and B. orellana areas showed the highest speed of decomposition, while the opposite situation occurred under T. grandiflorum and P. cupana cultivation.

A serrapilheira depositada na superfície do solo, em vários estágios de decomposição tem importância na produtividade primária que impacta nas comunidades microbianas e estocagem de carbono no solo. Objetivouse neste trabalho avaliar o acúmulo e decomposição dos resíduos culturais de cupuaçu, guaraná, urucum e floresta na região do Amazonas. O estudo foi realizado no assentamento São Francisco, Canutama no Sul do Amazonas, em delineamento experimental de blocos casualisados, sendo que os tratamentos constaram de quatro áreas com diferentes culturas: 1- Guaraná; 2 ­ Cupuaçu; 3 ­ Urucum; 4 ­ Área de mata nativa (floresta), em parcelas subdivididas no tempo: 07, 15, 30, 60, 90, 120, 150, 180, 210, 240, 270 e 300, 330 dias após a distribuição das sacolas no campo, todas com 04 repetições. Para avaliar o aporte e frações dá serapilheira, foram utilizados coletores cônicos em cada área, sendo as coletas realizadas mensalmente no período de março de 2020 a fevereiro de 2021. A estimativa da taxa de decomposição da serrapilheira foi realizada pela quantificação da perda de massa, utilizando-se litter bags, os quais permitem analisar de forma direta a taxa de decaimento ao longo do tempo. Os ambientes de floresta e guaraná apresentaram as maiores produções de serapilheira, e maior deposição quando comparados aos ambientes cultivados com cupuaçu e urucum. As áreas de floresta e urucum apresentaram a maior velocidade de decomposição, já a situação inversa ocorreu sob o cultivo do cupuaçu e guaraná.

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Several emerging viral agents related to gastroenteritis are distributed in human and animal populations and may contaminate the environment due to anthropic activities. The objective of this study was to analyze the seasonal contamination by enteric virus and coliforms in water from streams in the Vale do Taquari, draining a large number of pig farms. Microbiological contamination was evidenced by the detection of total and thermotolerant coliforms, reaching their peak in December. Hepatitis E virus (HEV), Enterovirus-G (EV-G) genome, and Sapelovirus-A (SV-A) genome were not detected. On the other hand, Rotavirus (RV) was detected in 3% (1/32) of the samples, whereas Teschovirus-A (PTV) was detected in 6% (2/32). This is the first detection of PTV in environmental samples in Brazil, pointing that the virus is being shedded from swine herds to watersheds. Human mastadenovirus (HAdV) was the most frequent detected viral agent in 9.3% (3/32) with values of 2.54 × 105, 7.13 × 104, and 3.09 × 105 genome copies/liter (gc/L). The circulation of coliforms and viral pathogens is noticeable due to anthropic activities and to the management of animal waste from the pig farming. In this way, enteric viruses can assist in monitoring the quality of watersheds and in tracking sources of contamination.

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We have investigated the structural, bonding, and electronic properties of both ferroelectric (FE) and paraelectric (PE) phases of the hexagonal LuMnO3 compound using calculations based on density functional theory. The structural properties have been determined by employing the generalized gradient approximation with Perdew-Burke-Ernzerhof and Wu-Cohen parameterization. The bonding and electronic properties have been treated by recently developed modified Becke-Johnson exchange potential, which succeeded to open a band gap for both PE and FE phases, in agreement with experimental predictions. The Bader's topological analysis of electronic density showed that the character of the Lu-O axial bonds changes when the crystal exhibits the PE → FE structural transition. This fact is in agreement with experimental findings. The covalent character of the Lu-O bond significantly increases due to orbital hybridization between the Lu 5dz(2) and O 2pz-states. This bonding mechanism causes the ferroelectricity in the hexagonal LuMnO3 compound.

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Structural, electronic and optical properties of the antisite BiMO4 defect in Bi12MO20 sillenites (BMO, M=Si, Ge, Ti) were investigated using density functional theory. The defect is studied in neutral, positively and negatively charged states. It is demonstrated that within the neutral defect the Bi 6s(2) lone pair is broken and the valence state of the Bi is 4+ (6s(1)). Within the charged defects, the Bi 6s orbital is found to be either full (Bi(3+): 6s(2)) or empty (Bi(5+): 6s(0)). All three charged states introduce energy bands within the BMO gap. By analyzing possible transitions between them we deduced a simple model of functioning of the BiMO4 defect that is able to explain the photochromic and photorefractive effect in sillenites and that reproduces almost all known experimental facts.

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Since all analgesics currently available for use in dogs have been associated with some adverse effects, the search for an effective analgesic that does not cause harm is important. This study investigated the postoperative analgesic effects of ozone administered either intrarectally or into acupoints in bitches undergoing ovariohysterectomy (OH). Twenty-four healthy adult bitches were randomly assigned to one of the three treatments 10 min after sedation, as follows: 0.2mg/kg of intramuscular (IM) meloxicam (M); rectal insufflation of 10 mL of 30 µg/mL ozone (OI), or acupoint injection of 0.5 mL ozone (30 µg/mL; OA). Following sedation with acetylpromazine, anaesthesia was induced with propofol and fentanyl and maintained with isoflurane/O2. Pain was assessed using the modified Glasgow pain scale (MGPS) and the visual analogue scale (VAS) on the day before surgery, before anaesthesia, and at 1, 2, 4, 6, 8, 12 and 24h after surgery. Rescue analgesia was performed using 0.5mg/kg of morphine IM if MGPS was >3.33 points. No statistically significant differences in pain scales were found among the three analgesic protocols or the time points in each group (P>0.05). Two dogs treated with OA required rescue analgesia. Meloxicam, rectal insufflation of ozone and ozone injected into acupoints provided satisfactory analgesia for 24h in bitches undergoing elective OH. Ozone had no measurable adverse effects and is an alternative option to promote pain relief.

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Studies focusing on communities of helminths from Brazilian lizards are increasing, but there are many blanks in the knowledge of parasitic fauna of wild fauna. This lack of knowledge hampers understanding of ecological and parasitological aspects of involved species. Moreover, the majority of research has focused on parasitic fauna of lizards from families Tropiduridae and Scincidae. Only a few studies have looked at lizards from the family Leiosauridae, including some species of Enyalius. This study presents data on the gastrointestinal parasite fauna of Enyalius perditus and their relationships with ecological aspects of hosts in a disturbed Atlantic rainforest area in the state of Minas Gerais, south-eastern Brazil. Two nematode species, Oswaldocruzia burseyi [(Molineidae) and Strongyluris oscari (Heterakidae) were found. Nematode species showed an aggregated distribution in this host population, with O. burseyi being more aggregated than S. oscari. The present study extends the range of occurrence of O. burseyi to the Brazilian continental area.

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The aim of this study was to evaluate the influence of tooth bleaching on the push-out bond strength of a composite resin based on dimethacrylates and silorane to cavities that involve both enamel and dentin. A total of 80 bovine incisors were sectioned on the buccal surface to obtain specimens (10 × 10 mm) presenting enamel and dentin (1-mm thick each substrate). The specimens were randomly distributed into eight groups (n=10), according to the bleaching protocol (1--none; 2--10% carbamide peroxide [CP] for 21 days, six hours each day; 3--three applications of 35% hydrogen peroxide [HP] in 15-minute sessions, one session every seven days for three weeks; 4--10% CP for 18 days, six hours each day + three applications of 35% HP in 15-minute sessions, one session every seven days for three weeks) and the restorative system applied (Adper Single Bond 2 + Filtek Supreme; Filtek Silorane adhesive and composite resin). After treatment, cavities were made (1.2-mm diameter on dentin; 1.5-mm diameter on enamel) with a diamond bur. At 24 hours after restoration, a push-out bond strength test was performed at a crosshead speed of 0.5 mm/min. The bleaching treatments did not significantly affect the bond strengths of either restorative system to enamel-dentin. Regardless of the bleaching treatment, the dimethacrylate-based resin system exhibited significantly higher bond strengths to enamel-dentin than did the silorane-based system.

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This in vitro study evaluated microleakage in Class II cavities restored with dental composite and varying light-curing units and the temperature of the composite when subjected to a thermocycling test. Ninety cavities were prepared on the proximal surfaces of bovine teeth and randomly divided according to the light-curing mode (QTH-420 mW/cm2, LED 2nd generation-1100 mW/cm2, or LED 3rd generation-700 mW/cm2) and temperature of the resin composite (23°C, 54°C and 60°C). Following the restorative procedures and thermocycling, the samples were immersed in methylene blue for 12 hours. The samples were ground and the powder prepared for analysis in an absorbance spectrophotometer. All the results were statistically analyzed using the nonparametric tests of Kruskal-Wallis and Dunn (p ≤ 0.05). The results showed that there was no statistical difference between the light-curing modes at a temperature of 23°C. For 54°C, QTH showed a microleakage mean that was significantly lower than those of the LED groups, and for 60°C, QTH had a microleakage mean significantly lower than that of the LED 2nd generation group. There was no statistical difference between the temperatures of the resin composite when LEDs were used. For QTH, 54°C showed statistically lower microleakage than 23°C. The group preheated to 60°C showed no difference when compared to the group heated to 23°C. Preheating the resin composite (54°C and 60°C) did not improve the microleakage means when high-irradiance LED was used; however, it decreased the microleakage means when a QTH with low irradiance was used.

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OBJECTIVES: This study evaluated the effects of the exposure time of eugenol-based provisional restorative material and the time elapsed between the provisional material removal and the adhesive procedure on the bond strength of the composite to dentin. MATERIALS AND METHODS: Human third molars were sectioned into two halves that were enclosed in resin cylinders. The cavities were prepared over the buccal/lingual faces with diamond burs. Zinc oxide and eugenol (ZOE) provisional material was inserted into cavities and left for 24 hours, 7 days or 14 days. The cavities not restored with ZOE were used as controls. After ZOE removal or over fresh dentin (control), self-etching Adper SE Plus was applied immediately, after a 7- or 14-day delay. The cavity was restored with non-eugenol provisional material during this delay period. Cylinders of resin cement were built-up over the hybridized dentin. A shear load was applied to the cylinders at a crosshead speed of 0.5 mm/minute until failure. The data were statistically analyzed using two-way ANOVA and Tukey's tests (α=0.05). RESULTS: Using IRM as a provisional restoration for 24 hours followed by its removal and immediate adhesive application resulted in the lowest values of shear bond strength. There was no significant difference between the other experimental conditions. CONCLUSIONS: The use of IRM for 24 hours adversely affected the shear bond strength of a self-etching adhesive to dentin. The recovery of the proper bond strength occurred one week after IRM removal.

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A contracepção cirúrgica é utilizada no controle populacional, por impedir definitivamente a reprodução e ser mais econômica em relação à eutanásia. As complicações ocorrem pela intervenção cirúrgica ou por efeitos sistêmicos da privação do estrógeno. Objetivou-se monitorar o período pós-operatório de cadelas e gatas castradas em projeto de extensão universitária, com o intuito de avaliar os benefícios e a incidência de efeitos adversos. Foram questionados por telefone os proprietários de 178 fêmeas castradas (135 caninas e 43 felinas), entre um e dois anos após a cirurgia. As questões envolviam o estado atual do animal, possível mortalidade, neste caso a causa da morte e quanto tempo após a cirurgia ocorreu, se ocorreram alterações físicas como ganho de peso, incontinência urinária e dermatite peri-vulvar e alterações comportamentais positivas, como docilidade e diminuição do comportamento de perambulação, ou negativas, como apatia, agressividade e agitação excessiva. Das 135 cadelas castradas, 12 (8,89%) apresentaram óbito, apenas um relacionado à cirurgia, 87 (64,44%) apresentaram ganho de peso após a cirurgia, uma (0,74%) apresentou incontinência urinária e quatro (2,96%) dermatite peri-vulvar. Alterações de comportamento positivas foram relatadas em 38 (28,15%) cadelas e negativas em seis (4,44%). Das 43 gatas castradas, seis (13,95%) apresentaram óbito, nenhum relacionado

RESUMO

A procriação excessiva de cães e gatos no ambiente urbano é um problema de saúde pública e de bem estar animal. Para se desenvolver campanhas de controle populacional necessita-se de protocolos cirúrgicos seguros, rápidos e de baixo custo. A abraçadeira auto-estática de náilon aparentemente se encaixa neste perfil. Objetivou-se avaliar por laparoscopia e histologia, a reação tecidual após a ligadura dos pedículos ovarianos com abraçadeira auto-estática ou mononáilon agulhado na ovariosalpingohisterectomia em 18 cadelas. Após 60 dias do procedimento cirúrgico não foi observada pela laparoscopia nenhuma aderência ou alteração macroscópica e a histologia dos fragmentos dos pedículos ovarianos demonstrou que a resposta tecidual não diferiu entre os métodos, revelando que a abraçadeira auto-estática pode ser usada como método de ligadura dos pedículos ovarianos de cadelas submetidas à ovariosalpingohisterectomia.

RESUMO

A contracepção cirúrgica é utilizada no controle populacional, por impedir definitivamente a reprodução. As complicações ocorrem pela intervenção cirúrgica ou por efeitos sistêmicos da privação do estrógeno. Objetivou-se monitorar o período pós-operatório de cadelas e gatas castradas em projeto de extensão universitária, com o intuito de avaliar os benefícios e a incidência de efeitos adversos. Foram questionados por telefone os proprietários de 178 fêmeas castradas (135 caninas e 43 felinas), entre um e dois anos após a cirurgia. As questões envolviam o estado atual do animal, possível mortalidade, neste caso a causa da morte e quanto tempo após a cirurgia ocorreu, se ocorreram alterações fisicas como ganho de peso, incontinência urinária e dermatite peri-vulvar e alterações comportamentais positivas, como docilidade e diminuição do comportamento de perambulação, ou negativas, como apatia, agressividade e agitação excessiva. Das 135 cadelas castradas, 12 (8,89%) apresentaram óbito, apenas um relacionado à cirurgia, 87 (64,44%) apresentaram ganho de peso após a cirurgia, uma (0,74%) apresentou incontinência urinária e quatro (2,96%) dermatite peri-vulvar. Alterações de comportamento positivas foram relatadas em 38 (28,15%) cadelas e negativas em seis (4,44%). Das 43 gatas castradas, seis (13,95%) apresentaram óbito, nenhum relacionado à cirurgia, 25 (58,14%) apresentaram ganho de peso, uma (2,32%) incontinência urinária e duas (4,65%) dermatite peri-vulvar. Alterações de comportamento positivas ocorreram em 20 fêmeas (46,51%) e alterações negativas em nenhuma fêmea (0%). Pode-se concluir que a contracepção cirúrgica apresenta boa relação custo-benefício no que diz respeito a alterações pós-operatórias de longo prazo.

Surgical contraception is widely used for animal population control. Both the surgical intervention and estrogen deprivation may produce postoperative complications. This was a retrospective study to investigate postoperative outcome of dogs and cats after surgical contraception. A number of 178 owners of 135 bitches and 43 cats were interviewed by phone from one to two years after surgery. Questions involved the actual state of the animals, possible deaths, in this case the cause of the deaths, and how long death occurred after surgery, physical changes after surgery, like weight gain, urinary incontinence, and perivulvar dermatitis and positive and negative behavior changes. Death was reported in 12 (8,89%) bitches, but in only in one case this was associated with surgery. Weight gain was reported in 87 (64,44%), urinary incontinence in one (0,74%) and perivulvar dermatitis in four (2,96%) bitches. Positive and negative behavior changes were reported in 38 (28,15%) and six (4,44%) bitches respectively. Six cats died (13.95%) in the period, but none death was associated with surgery. Weight gain as reported in 25 (58,14%), urinary incontinence in one (2,32%) and perivulvar dermatitis in two (4,65%) cats. Positive behavior changes were reported in 20 (46,51%) cats. No negative behavior change was observed in the cats. It was possible to conclude that surgical contraception shows a good cost-benefit relation when long term postoperative changes are concerned.

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A procriação excessiva de cães e gatos no ambiente urbano é um problema de saúde pública e de bem estar animal. Para se desenvolver campanhas de controle populacional necessita-se de protocolos cirúrgicos seguros, rápidos e de baixo custo. A abraçadeira auto-estática de nailon aparentemente se encaixa neste perfil. Objetivou-se avaliar por laparoscopia e histologia, a reação tecidual após a ligadura dos pedículos ovarianos com abraçadeira auto-estática ou mononáilon agulhado na ovariossalpingohisterectomia em 18 cadelas. Após 60 dias do procedimento cirúrgico não foi observada pela laparoscopia nenhuma aderência ou alteração macroscópica e a histologia dos fragmentos dos pedículos ovarianos demonstrou que a resposta tecidual não diferiu entre os métodos, revelando que a abraçadeira auto-estática pode ser usada como método de ligadura dos pedículos ovarianos de cadelas submetidas à ovariossalpingohisterectomia.

The excessive population of dogs and cats in cities is a public health and animal welfare problem. Safe, rapid and low cost antinoceptive surgical protocols should be used under these circumstances for population control. The nylon tide apparently fits in this profile. The aim of this study was to investigate the macroscopical and histological changes after nylon tide or nylon line for ovarian pedicle ligature in 18 bitches submitted to ovariohisterectomy. Adherence and macroscopical changes were not observed sixty days after the surgical procedure and there was no difference between the two techniques at the histological evaluation. It was concluded that nylon tide may be used for ovarian pedicle ligature in bitches submitted to ovariohysterectomy.

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The aim of this study was to investigate the impact of a 24-h cooling period prior to freezing on domestic cat epididymal sperm viability. Fifteen tomcats were submitted to routine orchiectomy and sperm samples were retrieved from both epididymides in a Tris-glucose-20% egg yolk extender. For each tomcat, the diluted sperm was split into two equal volumes and cooled to 5 degrees C at a rate of 0.5 degrees C/min; one sample for 60 min (control) and the other for 24 h (cooled). After the cooling period, samples from both groups were frozen using an identical freezing protocol. Sperm samples were evaluated in three different periods: immediately after harvesting, after cooling at 5 degrees C for 24 h (cooled group) and after freezing-thawing of control and cooled groups. Evaluations consisted of sperm motility and progressive status, sperm morphology and plasma membrane integrity (PMI) using two fluorescent probes. After cooling for 24 h, a decrease (p < 0.05) in sperm motility, progressive status and PMI was observed when compared to sperm samples immediately after collection. Comparing the results obtained after thawing, no difference (p < 0.05) was found regarding sperm motility, progressive status, PMI and sperm morphology between control and cooled groups. The results from the present study show that cooling cat epididymal spermatozoa at 5 degrees C for 24 h prior to freezing does not lead to major damage of spermatozoa impairing the freeze-thaw process.

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Avaliou-se o comportamento mecânico do polímero de mamona, tendo por variáveis o tempo de produção e a presença de catalisador, e utilizando como padrão comparativo o cimento ósseo (polimetilmetacrilato). Foram estabelecidos três grupos experimentais, de acordo com o tipo de corpo de prova (cilindro ou barra) e polímero utilizado, que foram posteriormente subdivididos em subgrupos conforme o tempo após produção, ou seja, 24, 48 e 72 horas. O ensaio de compressão analisou a carga máxima e a tensão e o ensaio de dobramento estudou o módulo de dobramento e a resistência. Estatisticamente não houve diferenças nos valores de resistência à compressão ou ao dobramento às 24, 48 e 72 horas após a produção do polimetilmetacrilato e da poliuretana, com ou sem catalisador. A poliuretana com catalisador foi a mais resistente nos ensaios de compressão, apresentando módulo de dobramento semelhante ao do polimetilmetacrilato e resistência ao dobramento superior à da poliuretana sem catalisador. Conclui-se que: o tempo não alterou as propriedades mecânicas dos compósitos avaliados; o catalisador melhorou o desempenho mecânico da poliuretana de mamona; na resistência mecânica à compressão, a poliuretana com catalisador suportou mais carga que o polimetilmetacrilato.(AU)

The mechanical properties of castor oil-based polyurethane was evaluated considering post-production time and the presence of a catalyst as variables and using bone cement (polymethylmetacrylate) as a comparative pattern. According to proof body type (cylinders or bars) and the used polymer, three experimental groups were established. Such groups were later subdivided according to post-production time, namely, 24, 48, and 72 hours. A compression assay analyzed maximum load and tension, and a folding assay evaluated the folding module and resistance. There were no statistical differences in the values for resistance to compression or folding at 24, 48, and 72 hours after the production of polymethylmetacrylate and polyurethane with or without a catalyst. Castor oil-based polyurethane with a catalyst showed to be the most resistant during the compression assays as its folding module was similar to that of polymethylmetacrylate, and its folding resistance was higher than that of polyurethane without a catalyst. In conclusion, time did not change the mechanical properties of the evaluated composites; the catalyst improved the mechanical performance of castor oil-based polyurethane; castor oil-based polyurethane with a catalyst supported more load during the assay for mechanical resistance to compression than did polymethylmetacrylate.(AU)

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Avaliou-se o comportamento mecânico do polímero de mamona, tendo por variáveis o tempo de produção e a presença de catalisador, e utilizando como padrão comparativo o cimento ósseo (polimetilmetacrilato). Foram estabelecidos três grupos experimentais, de acordo com o tipo de corpo de prova (cilindro ou barra) e polímero utilizado, que foram posteriormente subdivididos em subgrupos conforme o tempo após produção, ou seja, 24, 48 e 72 horas. O ensaio de compressão analisou a carga máxima e a tensão e o ensaio de dobramento estudou o módulo de dobramento e a resistência. Estatisticamente não houve diferenças nos valores de resistência à compressão ou ao dobramento às 24, 48 e 72 horas após a produção do polimetilmetacrilato e da poliuretana, com ou sem catalisador. A poliuretana com catalisador foi a mais resistente nos ensaios de compressão, apresentando módulo de dobramento semelhante ao do polimetilmetacrilato e resistência ao dobramento superior à da poliuretana sem catalisador. Conclui-se que: o tempo não alterou as propriedades mecânicas dos compósitos avaliados; o catalisador melhorou o desempenho mecânico da poliuretana de mamona; na resistência mecânica à compressão, a poliuretana com catalisador suportou mais carga que o polimetilmetacrilato.

The mechanical properties of castor oil-based polyurethane was evaluated considering post-production time and the presence of a catalyst as variables and using bone cement (polymethylmetacrylate) as a comparative pattern. According to proof body type (cylinders or bars) and the used polymer, three experimental groups were established. Such groups were later subdivided according to post-production time, namely, 24, 48, and 72 hours. A compression assay analyzed maximum load and tension, and a folding assay evaluated the folding module and resistance. There were no statistical differences in the values for resistance to compression or folding at 24, 48, and 72 hours after the production of polymethylmetacrylate and polyurethane with or without a catalyst. Castor oil-based polyurethane with a catalyst showed to be the most resistant during the compression assays as its folding module was similar to that of polymethylmetacrylate, and its folding resistance was higher than that of polyurethane without a catalyst. In conclusion, time did not change the mechanical properties of the evaluated composites; the catalyst improved the mechanical performance of castor oil-based polyurethane; castor oil-based polyurethane with a catalyst supported more load during the assay for mechanical resistance to compression than did polymethylmetacrylate.

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ABSTRACT This note reports parasitism by Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae) on the cigarette beetle that was found infesting opened pet-food bags in Rio de Janeiro retail pet store. The larvae were maintained under controlled laboratorial conditions in order to obtain the adult stage. From the pupae obtained from the laboratory, 84.6% were parasitized, 10.27% produced beetles and 5.13% had no emergence. This hymenoptera is an important natural enemy of some vectors and stored-product pests, being an alternative in the biological control of the species Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae).

RESUMO Nesta nota é relatada o parasitismo de Anisopteromalus calandrae (Hymenoptera: Pteromalidae) sobre Lasioderma serricorne encontrado infestando rações de animais domésticos em loja de produtos veterinários na Cidade do Rio de Janeiro. As larvas deste coleóptero foram mantidas vivas sob temperatura, umidade relativa controladas e fotoperíodo de 12h, objetivando-se o desenvolvimento das formas adultas. Das pupas obtidas em laboratório, 84,6% emergiram parasitóides, 10,27% emergiram besouros e de 5,13% das pupas não foi verificada nenhuma emergência. Este parasitóide é considerado um eficiente inimigo natural de alguns vetores e pragas de produtos armazenados sendo, portanto, uma alternativa no controle biológico de Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae).