RESUMO

The genus Ctenomys comprises about 70 species with great chromosome diversity. The Corrientes group is one of the most chromosomally variable lineages in the genus, where the diploid number (2n) varies from 41 to 70. In this group, three nominal species and numerous polymorphic and polytypic populations have been described. In order to get insight into the chromosomal evolution of this species complex, we applied different banding and molecular cytogenetic techniques. The results were interpreted in an evolutionary context, based on mitochondrial cytochrome b analyses. Studied samples are representative of the broad chromosomal variability in the group, including specimens with 2n = 42 to 2n = 70. Heterochromatin was scarce but concentrated in a few chromosomes. Centromeric DAPI-negative heterochromatin was observed in some autosomal pairs, which differed among populations. Location and amount of DAPI-neutral heterochromatin within the Y chromosome varied among populations. The variable distribution of heterochromatin indicates its dynamic behavior. NORs were detected in one pair of autosomes, which also differed among some populations. Telomeric FISH signals were observed in all complements only at the chromosome ends. The Corrientes group belongs to a clade that also includes C. pearsoni, C. lami, C. minutus, C. ibicuiensis and C. torquatus. Almost all of these species are variable at the chromosomal level, suggesting that this is the ancestral condition of the clade. Within the Corrientes group, the observed low genetic divergence, in contrast with its high chromosomal variability, is indicative of decoupling between the rates of chromosomal and mitochondrial evolution.

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To deal with complex systems, microscopic and global approaches become of particular interest. Our previous results from the dynamics of large cell colonies indicated that their 2D front roughness dynamics is compatible with the standard Kardar-Parisi-Zhang (KPZ) or the quenched KPZ equations either in plain or methylcellulose (MC)-containing gel culture media, respectively. In both cases, the influence of a non-uniform distribution of the colony constituents was significant. These results encouraged us to investigate the overall dynamics of those systems considering the morphology and size, the duplication rate, and the motility of single cells. For this purpose, colonies with different cell populations (N) exhibiting quasi-circular and quasi-linear growth fronts in plain and MC-containing culture media are investigated. For small N, the average radial front velocity and its change with time depend on MC concentration. MC in the medium interferes with cell mitosis, contributes to the local enlargement of cells, and increases the distribution of spatio-temporal cell density heterogeneities. Colony spreading in MC-containing media proceeds under two main quenching effects, I and II; the former mainly depending on the culture medium composition and structure and the latter caused by the distribution of enlarged local cell domains. For large N, colony spreading occurs at constant velocity. The characteristics of cell motility, assessed by measuring their trajectories and the corresponding velocity field, reflect the effect of enlarged, slow-moving cells and the structure of the medium. Local average cell size distribution and individual cell motility data from plain and MC-containing media are qualitatively consistent with the predictions of both the extended cellular Potts models and the observed transition of the front roughness dynamics from a standard KPZ to a quenched KPZ. In this case, quenching effects I and II cooperate and give rise to the quenched-KPZ equation. Seemingly, these results show a possible way of linking the cellular Potts models and the 2D colony front roughness dynamics.

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Abstract Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) is an important predator of the insect pest Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). The present study investigated the pre-imaginal development of S. decastigmus at different temperatures. The temperatures were: 20, 25, and 30 °C, with a relative humidity of 70 ± 10% and a photofase of 12 h, and the nymphs were fed larvae of M. ochroloma. We evaluated the duration and viability of the egg and nymphal stages, the duration of each instar, and the predation potential. The incubation time decreased with increasing temperature, and the viability was highest at 25 °C. The duration of the nymphal stage was inversely proportional to the temperature, ranging from 18 days at 30 °C to 40.6 days at 20 °C. The highest S. decastigmus predation rates were found at 20 °C (90.4 larvae) and 30 °C (72.5 larvae). S. decastigmus showed the highest viability and lowest consumption of larvae of M. ochroloma at 25 °C.(AU)

Resumo Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) é um importante predador do inseto-praga Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). O objetivo deste trabalho foi estudar o desenvolvimento pré-imaginal de S. decastigmus em diferentes temperaturas. Foram utilizadas as temperaturas de 20, 25, e 30 °C, umidade relativa do ar de 70 ± 10% e fotofase de 12 h, sendo as ninfas alimentadas com larvas de M. ochroloma. Foram avaliados a duração e viabilidade dos estágios de ovo e ninfa, a duração de cada instar e o potencial de predação. O período de incubação diminuiu com o aumento da temperatura e apresentou maior viabilidade a 25 °C. A duração do estágio ninfal foi inversamente proporcional a temperatura com 18 dias a 30 °C e 40,6 dias a 20 °C. A maior taxa de predação de S. decastigmus foi encontrada a 20 °C (90,4 larvas) e 30 °C (72,5 larvas). S. decastigmus teve maior viabilidade e menor consumo de larvas de M. ochroloma a 25 °C.(AU)

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RESUMO

Abstract Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) is an important predator of the insect pest Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). The present study investigated the pre-imaginal development of S. decastigmus at different temperatures. The temperatures were: 20, 25, and 30 °C, with a relative humidity of 70 ± 10% and a photofase of 12 h, and the nymphs were fed larvae of M. ochroloma. We evaluated the duration and viability of the egg and nymphal stages, the duration of each instar, and the predation potential. The incubation time decreased with increasing temperature, and the viability was highest at 25 °C. The duration of the nymphal stage was inversely proportional to the temperature, ranging from 18 days at 30 °C to 40.6 days at 20 °C. The highest S. decastigmus predation rates were found at 20 °C (90.4 larvae) and 30 °C (72.5 larvae). S. decastigmus showed the highest viability and lowest consumption of larvae of M. ochroloma at 25 °C.

Resumo Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) é um importante predador do inseto-praga Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). O objetivo deste trabalho foi estudar o desenvolvimento pré-imaginal de S. decastigmus em diferentes temperaturas. Foram utilizadas as temperaturas de 20, 25, e 30 °C, umidade relativa do ar de 70 ± 10% e fotofase de 12 h, sendo as ninfas alimentadas com larvas de M. ochroloma. Foram avaliados a duração e viabilidade dos estágios de ovo e ninfa, a duração de cada instar e o potencial de predação. O período de incubação diminuiu com o aumento da temperatura e apresentou maior viabilidade a 25 °C. A duração do estágio ninfal foi inversamente proporcional a temperatura com 18 dias a 30 °C e 40,6 dias a 20 °C. A maior taxa de predação de S. decastigmus foi encontrada a 20 °C (90,4 larvas) e 30 °C (72,5 larvas). S. decastigmus teve maior viabilidade e menor consumo de larvas de M. ochroloma a 25 °C.

Assuntos

RESUMO

Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) is an important predator of the insect pest Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). The present study investigated the pre-imaginal development of S. decastigmus at different temperatures. The temperatures were: 20, 25, and 30 °C, with a relative humidity of 70 ± 10% and a photofase of 12 h, and the nymphs were fed larvae of M. ochroloma. We evaluated the duration and viability of the egg and nymphal stages, the duration of each instar, and the predation potential. The incubation time decreased with increasing temperature, and the viability was highest at 25 °C. The duration of the nymphal stage was inversely proportional to the temperature, ranging from 18 days at 30 °C to 40.6 days at 20 °C. The highest S. decastigmus predation rates were found at 20 °C (90.4 larvae) and 30 °C (72.5 larvae). S. decastigmus showed the highest viability and lowest consumption of larvae of M. ochroloma at 25 °C.

Assuntos

RESUMO

Abstract Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) is an important predator of the insect pest Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). The present study investigated the pre-imaginal development of S. decastigmus at different temperatures. The temperatures were: 20, 25, and 30 °C, with a relative humidity of 70 ± 10% and a photofase of 12 h, and the nymphs were fed larvae of M. ochroloma. We evaluated the duration and viability of the egg and nymphal stages, the duration of each instar, and the predation potential. The incubation time decreased with increasing temperature, and the viability was highest at 25 °C. The duration of the nymphal stage was inversely proportional to the temperature, ranging from 18 days at 30 °C to 40.6 days at 20 °C. The highest S. decastigmus predation rates were found at 20 °C (90.4 larvae) and 30 °C (72.5 larvae). S. decastigmus showed the highest viability and lowest consumption of larvae of M. ochroloma at 25 °C.

Resumo Stiretrus decastigmus (Herrich-Schaeffer) (Hemiptera: Pentatomidae) é um importante predador do inseto-praga Microtheca ochroloma Stal (Coleoptera: Chrysomelidae). O objetivo deste trabalho foi estudar o desenvolvimento pré-imaginal de S. decastigmus em diferentes temperaturas. Foram utilizadas as temperaturas de 20, 25, e 30 °C, umidade relativa do ar de 70 ± 10% e fotofase de 12 h, sendo as ninfas alimentadas com larvas de M. ochroloma. Foram avaliados a duração e viabilidade dos estágios de ovo e ninfa, a duração de cada instar e o potencial de predação. O período de incubação diminuiu com o aumento da temperatura e apresentou maior viabilidade a 25 °C. A duração do estágio ninfal foi inversamente proporcional a temperatura com 18 dias a 30 °C e 40,6 dias a 20 °C. A maior taxa de predação de S. decastigmus foi encontrada a 20 °C (90,4 larvas) e 30 °C (72,5 larvas). S. decastigmus teve maior viabilidade e menor consumo de larvas de M. ochroloma a 25 °C.

RESUMO

Microtheca spp. (Coleoptera: Chrysomelidae) are insect pests primarily related to Brassicaceae crops. In the State of Rio Grande do Sul (RS), southern Brazil, they are found on forage turnip, Raphanus sativus L. var. oleiferus Metzg., which is commonly grown during fall/winter seasons. This work reports the predation of Microtheca spp. larvae by Toxomerus duplicatus Wiedemann, 1830 (Diptera: Syrphidae) larvae, on forage turnip crop, in Santa Maria, RS. This register provides new information about Microtheca spp. natural enemies in Brazil, which might be a new option for integrate pest management of these species.

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The interfacial two-dimensional spreading dynamics of quasilinear Vero cell colony fronts in methylcellulose (MC)-containing culture medium, under a constant average front displacement velocity regime, was investigated. Under comparable experimental conditions, the average colony front displacement velocity becomes lower than that reported for a standard culture medium. Initially, the presence of MC in the medium hinders both the colony spreading, due to a gradual change in the average size and shape of cells and their distribution in the colony, and the cell motility in the gelled medium. Furthermore, at longer culture times enlarged cells appear at random in the border region of the colony. These cells behave as obstacles (pinning sites) for the displacement of smaller cells towards the colony front. The dynamic scaling analysis of rough fronts yields the set of exponents α=0.63±0.04,ß=0.75±0.05, and z=0.84±0.05, which is close to that expected for a quenched Kardar-Parisi-Zhang model.

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RESUMO

Microtheca spp. (Coleoptera: Chrysomelidae) are insect pests primarily related to Brassicaceae crops. In the State of Rio Grande do Sul (RS), southern Brazil, they are found on forage turnip, Raphanus sativus L. var. oleiferus Metzg., which is commonly grown during fall/winter seasons. This work reports the predation of Microtheca spp. larvae by Toxomerus duplicatus Wiedemann, 1830 (Diptera: Syrphidae) larvae, on forage turnip crop, in Santa Maria, RS. This register provides new information about Microtheca spp. natural enemies in Brazil, which might be a new option for integrate pest management of these species.(AU)

Microtheca spp. (Coleoptera: Chrysomelidae) são insetos-praga relacionados principalmente às culturas da família Brassicaceae. No Estado do Rio Grande do Sul (RS), no sul do Brasil, são encontrados no nabo forrageiro, Raphanus sativus L. var. oleiferus Metzg, comumente cultivado no outono/inverno. Este trabalho relata a predação de larvas de Microtheca spp. por larvas de Toxomerus duplicatus Wiedemann, 1830 (Diptera: Syrphidae), em nabo forrageiro, em Santa Maria, RS. Este registro oferece nova informação sobre os inimigos naturais de Microtheca spp. no Brasil os quais podem ser uma nova opção para o manejo integrado dessas espécies.(AU)

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RESUMO

Microtheca spp. (Coleoptera: Chrysomelidae) are insect pests primarily related to Brassicaceae crops. In the State of Rio Grande do Sul (RS), southern Brazil, they are found on forage turnip, Raphanus sativus L. var. oleiferus Metzg., which is commonly grown during fall/winter seasons. This work reports the predation of Microtheca spp. larvae by Toxomerus duplicatus Wiedemann, 1830 (Diptera: Syrphidae) larvae, on forage turnip crop, in Santa Maria, RS. This register provides new information about Microtheca spp. natural enemies in Brazil, which might be a new option for integrate pest management of these species.

Microtheca spp. (Coleoptera: Chrysomelidae) são insetos-praga relacionados principalmente às culturas da família Brassicaceae. No Estado do Rio Grande do Sul (RS), no sul do Brasil, são encontrados no nabo forrageiro, Raphanus sativus L. var. oleiferus Metzg, comumente cultivado no outono/inverno. Este trabalho relata a predação de larvas de Microtheca spp. por larvas de Toxomerus duplicatus Wiedemann, 1830 (Diptera: Syrphidae), em nabo forrageiro, em Santa Maria, RS. Este registro oferece nova informação sobre os inimigos naturais de Microtheca spp. no Brasil os quais podem ser uma nova opção para o manejo integrado dessas espécies.

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Um experimento foi conduzido com o objetivo de avaliar as características da carcaça e dos componentes não carcaça de cordeiros nascidos de parto simples ou duplo. Dezesseis cordeiros mestiços Texel × Ile de France, machos não castrados, foram desmamados aos 56 dias de idade e abatidos com aproximadamente 28kg de peso corporal. Imediatamente após o abate, cada componente corporal foi pesado separadamente, sendo as carcaças avaliadas após 24 horas de refrigeração a 2°C. Os cordeiros oriundos de parto simples apresentaram superioridade no peso e nos rendimentos da carcaça, além de maior área de olho de lombo. Por outro lado, proporcionalmente ao peso de corpo vazio, o rúmen é maior em cordeiros nascidos de parto duplo, o que resulta incremento da proporção de conteúdo gastrintestinal ao abate. Os resultados deste estudo indicam que, quando abatidos a um mesmo peso, cordeiros oriundos de parto simples possuem carcaças de melhor qualidade, em comparação a cordeiros nascidos de parto gemelar.(AU)

An experiment was conducted to evaluate the carcass and non-carcass traits of single and twin lambs. Sixteen Texel × Ile de France crossbred, non-castrated male lambs were weaned at 56 days of age and slaughtered at 28kg of body weight. Immediately after the slaughter each body component was individually weighed, while carcasses were evaluated after a 24h period of refrigeration at 2°C. Single lambs presented higher values of carcass weight and carcass dressing percentage. Moreover, the Longissimus muscle area was also greater for single lambs. On the other hand, as a proportion of empty body weight, rumen was greater for twin lambs, increasing their gastrointestinal content at slaughter. The results of this study indicated that at a same slaughter weight single lambs have better quality carcasses in comparison with those from twin lambs.(AU)

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RESUMO

Um experimento foi conduzido com o objetivo de avaliar as características da carcaça e dos componentes não carcaça de cordeiros nascidos de parto simples ou duplo. Dezesseis cordeiros mestiços Texel × Ile de France, machos não castrados, foram desmamados aos 56 dias de idade e abatidos com aproximadamente 28kg de peso corporal. Imediatamente após o abate, cada componente corporal foi pesado separadamente, sendo as carcaças avaliadas após 24 horas de refrigeração a 2°C. Os cordeiros oriundos de parto simples apresentaram superioridade no peso e nos rendimentos da carcaça, além de maior área de olho de lombo. Por outro lado, proporcionalmente ao peso de corpo vazio, o rúmen é maior em cordeiros nascidos de parto duplo, o que resulta incremento da proporção de conteúdo gastrintestinal ao abate. Os resultados deste estudo indicam que, quando abatidos a um mesmo peso, cordeiros oriundos de parto simples possuem carcaças de melhor qualidade, em comparação a cordeiros nascidos de parto gemelar...

An experiment was conducted to evaluate the carcass and non-carcass traits of single and twin lambs. Sixteen Texel × Ile de France crossbred, non-castrated male lambs were weaned at 56 days of age and slaughtered at 28kg of body weight. Immediately after the slaughter each body component was individually weighed, while carcasses were evaluated after a 24h period of refrigeration at 2°C. Single lambs presented higher values of carcass weight and carcass dressing percentage. Moreover, the Longissimus muscle area was also greater for single lambs. On the other hand, as a proportion of empty body weight, rumen was greater for twin lambs, increasing their gastrointestinal content at slaughter. The results of this study indicated that at a same slaughter weight single lambs have better quality carcasses in comparison with those from twin lambs...

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The objective of this study was to evaluate the clinical and histological effects of occluding the nasolacrimal ducts and points of rabbits. For this study, 20 adult New Zealand rabbits, both males and females, weighing 3.2±0.4kg were allocated into two groups for n-butyl-cyanoacrylate occlusion (GB, n=10) or 2-octyl-cyanoacrylate occlusion (GO, n=10). The contralateral eyes served as the controls. The persistence of tears was evaluated daily using the Schirmer I test. Discomfort, eye discharge, epiphora, and conjunctival hyperemia were assessed prior to the procedure (T0) and during the 14 subsequent days (T1-T14). On days seven and 14, five animals from each group were euthanized, and their nasolacrimal ducts were collected, processed and analyzed by histology. In the GB group, the Schirmer test values differed from that at T0 at all of the subsequent time points, whereas there was no difference in the values observed from the GO group. Compared with the corresponding controls, the GO and GB groups differed significantly at almost all of the time points. When comparing the treatment groups, differences were found at T6, T7, T9, T10, T11, T12 and T14, with higher Schirmer values in the GB group. Epiphora was observed in the GB group from T1 to T8 and in the GO group from T1 to T6. Within seven days post-occlusion, histology revealed a moderate foreign body reaction, with marked necrosis and sloughing of the canalicular epithelium, in the GO group, which was absent at day 14. In the GB group, a marked inflammatory reaction and a mild foreign body reaction were found at day seven, and the foreign body reaction was prevalent at day 14. This study demonstrated that both adhesives were effective in obstructing the nasolacrimal ducts and points of rabbits and that their application and handling are easy and free of complications. However, both adhesives promoted inflammatory and foreign body reactions that evolved to repair and regeneration at day 14 of evaluation.(AU)

Avaliaram-se os efeitos clínicos e histológicos da oclusão do ponto e do duto nasolacrimais de coelhos. Para isso, utilizaram-se 20 coelhos adultos da raça Nova Zelândia, machos e fêmeas, com peso de 3,2±0,4kg, distribuídos em dois grupos: oclusão com n-butil cianoacrilato (GB, n=10) e oclusão com 2-octil cianoacrilato (GO, n=10). Os olhos contralaterais foram utilizados como controle. A permanência da lágrima foi avaliada diariamente pelo teste de Schirmer I. Foram avaliados o desconforto, secreção ocular, epífora e hiperemia conjuntival, previamente ao procedimento (T0) e durante 14 dias (T1-T14). Aos sete e aos 14 dias, cinco animais de cada grupo foram submetidos à eutanásia, e os dutos nasolacrimais, colhidos, processados e analisados à histologia. Em GB, os valores de Schirmer diferiram de T0 em todos os momentos; em GO não houve diferença. Na comparação com o respectivo controle, GB e GO diferiram significativamente em quase todos os momentos. Ao compararem-se os tratamentos, houve diferença em T6, T7, T9, T10, T11, T12 e T14, sendo os valores de Schirmer superiores em GB. Epífora esteve presente em GB de T1 a T8 e em GO de T1 a T6. À histologia, em GO, aos sete dias, notou-se moderada reação de corpo estranho com marcante necrose e descamação do epitélio canalicular; tais alterações estiveram ausentes aos 14 dias. Em GB, verificou-se, aos sete dias, acentuada reação inflamatória e discreta reação de corpo estranho; aos 14 dias, houve predomínio da reação de corpo estranho. Concluiu-se que ambos os adesivos foram eficazes na obstrução do ponto e do duto nasolacrimais de coelhos, sendo sua aplicação e manuseio fáceis e livres de intercorrências e ambos promoveram reação inflamatória e de corpo estranho que evoluíram para reparação e regeneração aos 14 dias de avaliação.(AU)

Assuntos

RESUMO

The objective of this study was to evaluate the clinical and histological effects of occluding the nasolacrimal ducts and points of rabbits. For this study, 20 adult New Zealand rabbits, both males and females, weighing 3.2±0.4kg were allocated into two groups for n-butyl-cyanoacrylate occlusion (GB, n=10) or 2-octyl-cyanoacrylate occlusion (GO, n=10). The contralateral eyes served as the controls. The persistence of tears was evaluated daily using the Schirmer I test. Discomfort, eye discharge, epiphora, and conjunctival hyperemia were assessed prior to the procedure (T0) and during the 14 subsequent days (T1-T14). On days seven and 14, five animals from each group were euthanized, and their nasolacrimal ducts were collected, processed and analyzed by histology. In the GB group, the Schirmer test values differed from that at T0 at all of the subsequent time points, whereas there was no difference in the values observed from the GO group. Compared with the corresponding controls, the GO and GB groups differed significantly at almost all of the time points. When comparing the treatment groups, differences were found at T6, T7, T9, T10, T11, T12 and T14, with higher Schirmer values in the GB group. Epiphora was observed in the GB group from T1 to T8 and in the GO group from T1 to T6. Within seven days post-occlusion, histology revealed a moderate foreign body reaction, with marked necrosis and sloughing of the canalicular epithelium, in the GO group, which was absent at day 14. In the GB group, a marked inflammatory reaction and a mild foreign body reaction were found at day seven, and the foreign body reaction was prevalent at day 14. This study demonstrated that both adhesives were effective in obstructing the nasolacrimal ducts and points of rabbits and that their application and handling are easy and free of complications. However, both adhesives promoted inflammatory and foreign body reactions that evolved to repair and regeneration at day 14 of evaluation.

Avaliaram-se os efeitos clínicos e histológicos da oclusão do ponto e do duto nasolacrimais de coelhos. Para isso, utilizaram-se 20 coelhos adultos da raça Nova Zelândia, machos e fêmeas, com peso de 3,2±0,4kg, distribuídos em dois grupos: oclusão com n-butil cianoacrilato (GB, n=10) e oclusão com 2-octil cianoacrilato (GO, n=10). Os olhos contralaterais foram utilizados como controle. A permanência da lágrima foi avaliada diariamente pelo teste de Schirmer I. Foram avaliados o desconforto, secreção ocular, epífora e hiperemia conjuntival, previamente ao procedimento (T0) e durante 14 dias (T1-T14). Aos sete e aos 14 dias, cinco animais de cada grupo foram submetidos à eutanásia, e os dutos nasolacrimais, colhidos, processados e analisados à histologia. Em GB, os valores de Schirmer diferiram de T0 em todos os momentos; em GO não houve diferença. Na comparação com o respectivo controle, GB e GO diferiram significativamente em quase todos os momentos. Ao compararem-se os tratamentos, houve diferença em T6, T7, T9, T10, T11, T12 e T14, sendo os valores de Schirmer superiores em GB. Epífora esteve presente em GB de T1 a T8 e em GO de T1 a T6. À histologia, em GO, aos sete dias, notou-se moderada reação de corpo estranho com marcante necrose e descamação do epitélio canalicular; tais alterações estiveram ausentes aos 14 dias. Em GB, verificou-se, aos sete dias, acentuada reação inflamatória e discreta reação de corpo estranho; aos 14 dias, houve predomínio da reação de corpo estranho. Concluiu-se que ambos os adesivos foram eficazes na obstrução do ponto e do duto nasolacrimais de coelhos, sendo sua aplicação e manuseio fáceis e livres de intercorrências e ambos promoveram reação inflamatória e de corpo estranho que evoluíram para reparação e regeneração aos 14 dias de avaliação.

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The two-dimensional (2D) growth dynamics of HeLa (cervix cancer) cell colonies was studied following both their growth front and the pattern morphology evolutions utilizing large population colonies exhibiting linearly and radially spreading fronts. In both cases, the colony profile fractal dimension was d(f)=1.20±0.05 and the growth fronts displaced at the constant velocity 0.90±0.05 µm min(-1). Colonies showed changes in both cell morphology and average size. As time increased, the formation of large cells at the colony front was observed. Accordingly, the heterogeneity of the colony increased and local driving forces that set in began to influence the dynamics of the colony front. The dynamic scaling analysis of rough colony fronts resulted in a roughness exponent α = 0.50±0.05, a growth exponent ß = 0.32±0.04, and a dynamic exponent z=1.5±0.2. The validity of this set of scaling exponents extended from a lower cutoff l(c)≈60 µm upward, and the exponents agreed with those predicted by the standard Kardar-Parisi-Zhang continuous equation. HeLa data were compared with those previously reported for Vero cell colonies. The value of d(f) and the Kardar-Parisi-Zhang-type 2D front growth dynamics were similar for colonies of both cell lines. This indicates that the cell colony growth dynamics is independent of the genetic background and the tumorigenic nature of the cells. However, one can distinguish some differences between both cell lines during the growth of colonies that may result from specific cooperative effects and the nature of each biosystem.

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Microtheca semilaevis Stal is a phythophagous insect associated to Brassicaceae, and frequently occurs with other species of beetles, such as Microtheca ochroloma Stal. Despite its importance to organic farmers, there is no information in the Brazilian literature about its natural enemies. Stiretrus decastigmus (Herrich-Schaeffer) was first found and here reported preying an adult of M. semilaevis in Chinese cabbage in Santa Maria, RS, Brazil (29°43'28″S, 53°43'19″W).

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The dynamics of two-dimensional (2D) radially spreading growth fronts of Vero cell colonies was investigated utilizing two types of colonies, namely type I starting from clusters with a small number of cells, which initially exhibited arbitrary-shaped rough growth fronts and progressively approached quasicircular ones as the cell population increased; and type II colonies, starting from a relatively large circular three-dimensional (3D) cell cluster. For large cell population colonies, the fractal dimension of the fronts was D(F) = 1.20±0.05. For low cell populations, the mean colony radius increased exponentially with time, but for large ones the constant radial front velocity 0.20±0.02 µm min(-1) was reached. Colony spreading was accompanied by changes in both cell morphology and average size, and by the formation of very large cells, some of them multinuclear. Therefore the heterogeneity of colonies increased and local driving forces that set in began to influence the 2D growth front kinetics. The retardation effect related to the exponential to constant radial front velocity transition was assigned to a number of possible interferences including the cell duplication and 3D growth in the bulk of the colony. The dynamic scaling analysis of overhang-corrected rough colony fronts, after arc-radius coordinate system transformation, resulted in roughness exponent α = 0.50±0.05 and growth exponent ß = 0.32±0.04, for arc lengths greater than 100 µm. This set of scaling exponents agreed with that predicted by the Kardar, Parisi, and Zhang continuous equation. For arc lengths shorter than 2-3 cell diameters, the value α = 0.85±0.05 would be related to a cell front roughening caused by temporarily membrane deformations occasionally interfered by cell proliferation.

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