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Magnetic systems with competing anisotropies generally exhibit asymmetry between the maximum amplitudes of the right and left maxima in a magnetoimpedance curve. Small errors in positioning the samples at the experimental setup may also produce such asymmetry. In this work, we present a study on the sources of the asymmetry between magnetoimpedance peaks in systems that present the exchange bias phenomenon, by comparing a phenomenological model to experimental data. A set of samples with different repetitions of the NiFe/FeMn exchange-biased bilayer was used in this study. From the frequency evolution of the asymmetry, together with magnetization curves, we were able to identify the sources for the observed magnetoimpedance asymmetry found on our experimental data.

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AIMS: Penicillium digitatum, Alternaria alternata and Colletotrichum gloeosporioides are pathogens responsible for large decays and production losses of citrus. They are commonly controlled by fungicides, whose excessive applications have led to the emergence of resistant P. digitatum strains. Alternative approaches are imperative for sustainable and environmental harmless citrus production, being biological control a promising strategy. The objective was to evaluate the potential of Trichoderma strains native from the rhizosphere of citrus trees to control these pathogens. METHODS AND RESULTS: Seven strains were isolated and identified as Trichoderma harzianum, T. guizhouense, T. atroviride and T. koningiopsis through morphological and molecular analyses. Five of them showed effective antagonist performance in vitro against the pathogens. The strain T. harzianum IC-30 was the best biological control agent in vivo, obtaining a reduction of rot percentage around 80% after 3 weeks of infection of oranges with P. digitatum A21 (resistant to pyrimethanil). This strain also showed the highest chitinase and glucanase activities. CONCLUSIONS: Trichoderma harzianum IC-30 is an optimal antagonist for the control of green mould spreading and other pathogens in post-harvest citrus fruits. SIGNIFICANCE AND IMPACT OF THE STUDY: The strain combined with supplementary practices could lead to sustainable management of citrus fungal diseases, dispensing with synthetic fungicides.

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Este trabalho teve como objetivo avaliar o efeito do treinamento sobre as variáveis da cinemática de equinos jovens da raça Brasileiro de Hipismo no salto em liberdade. Foram utilizados 14 equinos da raça Brasileiro de Hipismo com idade de 40 a 42 meses, peso vivo de 436,3±11,6kg e 448,2±12,7kg e altura na cernelha de 1,57±0,03m e 1,58±0,03m ao início e ao final do experimento, respectivamente. Os equinos realizaram dois protocolos de avaliação de salto, um antes e outro após o treinamento. O treinamento teve a duração de cinco meses e consistiu em 50 minutos de atividade física por dia, montados, sendo dois dias de flexionamento, dois dias de condicionamento físico e dois dias de trabalho específico de salto de obstáculos. Nos protocolos de avaliação, foram filmados cinco saltos em liberdade sobre um obstáculo oxer, com o primeiro e o segundo elemento na altura de 0,90m e 1,00m de altura, respectivamente, e 0,90m de largura. Foram fixados marcadores reflexivos nos equinos em pontos anatômicos utilizados como pontos de referência para a avaliação das características cinemáticas no salto. As filmagens foram realizadas com câmera de 100Hz, e as imagens, processadas no Simi Reality Motion Systems (r). Os resultados das variáveis avaliadas foram comparados com o teste de t pareado (P<0,05). O treinamento resultou no aumento das variáveis (P<0,05): velocidade da passada anterior ao salto, velocidade do salto, deslocamento horizontal da cernelha no salto, ângulo escapuloumeral, distância vertical entre as articulações escapuloumeral e metacarpofalângica, ângulo coxofemoral e ângulo femorotibial. No entanto, os valores dos ângulos umerorradial e tibiometatarsiano apresentaram redução após o treinamento (P>0,05). Conclui-se que o treinamento específico para salto com cinco meses de duração altera algumas variáveis cinemáticas dos equinos no salto de obstáculo proporcionando melhoria, principalmente, na trajetória do salto...

This study was carried out to evaluate the effect of training on the kinematic traits of young Brazilian Sport Horse in free jumping. 14 Brazilian Sport Horse were used, aged between 40 and 42 months, with body weight of 436.3±11.6kg and 448.2±12.7kg and height withers of 1.58±0.03m and 1.58±0.03m at the beginning and end of training, respectively. Two jumping evaluation protocols were used: before and after training. The training had the duration of five months and consisted of 50 minutes of exercise activities by day with a rider; two days of flexing, two days of physical conditioning and two days of specific jumping exercises. The evaluations were carried out, and five free jumps in each evaluation were record in an oxer, with the front fence of 0.90m and the back fence of 1.00m height and 0.90m of width. The horse's anatomical points were highlighted by reflective markers. The recordings were performed with 100Hz camera and the images processed in Simi Reality Motion Systems(r). The results were analyzed as paired data (P<0.05). The training increased the traits kinematics (P<0.05): last stride velocity speed prior to jumping, jumping velocity, horizontal withers displacement at jumping, scapulohumeral angle, vertical distance between scapulohumeral and metacarpophalangeal joint, coxofemoral angle and femorotibial angle. However, the kinematic traits reduced with training: humeroradial angle and tibiometatarsal angle (P<0.05). In conclusion, the jumping training with a five month duration changed some kinematic traits of free jumping in horses, especially the jumping trajectory...

Assuntos

RESUMO

Este trabalho teve como objetivo avaliar o efeito do treinamento sobre as variáveis da cinemática de equinos jovens da raça Brasileiro de Hipismo no salto em liberdade. Foram utilizados 14 equinos da raça Brasileiro de Hipismo com idade de 40 a 42 meses, peso vivo de 436,3±11,6kg e 448,2±12,7kg e altura na cernelha de 1,57±0,03m e 1,58±0,03m ao início e ao final do experimento, respectivamente. Os equinos realizaram dois protocolos de avaliação de salto, um antes e outro após o treinamento. O treinamento teve a duração de cinco meses e consistiu em 50 minutos de atividade física por dia, montados, sendo dois dias de flexionamento, dois dias de condicionamento físico e dois dias de trabalho específico de salto de obstáculos. Nos protocolos de avaliação, foram filmados cinco saltos em liberdade sobre um obstáculo oxer, com o primeiro e o segundo elemento na altura de 0,90m e 1,00m de altura, respectivamente, e 0,90m de largura. Foram fixados marcadores reflexivos nos equinos em pontos anatômicos utilizados como pontos de referência para a avaliação das características cinemáticas no salto. As filmagens foram realizadas com câmera de 100Hz, e as imagens, processadas no Simi Reality Motion Systems (r). Os resultados das variáveis avaliadas foram comparados com o teste de t pareado (P<0,05). O treinamento resultou no aumento das variáveis (P<0,05): velocidade da passada anterior ao salto, velocidade do salto, deslocamento horizontal da cernelha no salto, ângulo escapuloumeral, distância vertical entre as articulações escapuloumeral e metacarpofalângica, ângulo coxofemoral e ângulo femorotibial. No entanto, os valores dos ângulos umerorradial e tibiometatarsiano apresentaram redução após o treinamento (P>0,05). Conclui-se que o treinamento específico para salto com cinco meses de duração altera algumas variáveis cinemáticas dos equinos no salto de obstáculo proporcionando melhoria, principalmente, na trajetória do salto.(AU)

This study was carried out to evaluate the effect of training on the kinematic traits of young Brazilian Sport Horse in free jumping. 14 Brazilian Sport Horse were used, aged between 40 and 42 months, with body weight of 436.3±11.6kg and 448.2±12.7kg and height withers of 1.58±0.03m and 1.58±0.03m at the beginning and end of training, respectively. Two jumping evaluation protocols were used: before and after training. The training had the duration of five months and consisted of 50 minutes of exercise activities by day with a rider; two days of flexing, two days of physical conditioning and two days of specific jumping exercises. The evaluations were carried out, and five free jumps in each evaluation were record in an oxer, with the front fence of 0.90m and the back fence of 1.00m height and 0.90m of width. The horse's anatomical points were highlighted by reflective markers. The recordings were performed with 100Hz camera and the images processed in Simi Reality Motion Systems(r). The results were analyzed as paired data (P<0.05). The training increased the traits kinematics (P<0.05): last stride velocity speed prior to jumping, jumping velocity, horizontal withers displacement at jumping, scapulohumeral angle, vertical distance between scapulohumeral and metacarpophalangeal joint, coxofemoral angle and femorotibial angle. However, the kinematic traits reduced with training: humeroradial angle and tibiometatarsal angle (P<0.05). In conclusion, the jumping training with a five month duration changed some kinematic traits of free jumping in horses, especially the jumping trajectory.(AU)

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A new set of derivative thioxothiazolidinones and thioxoimidazolidinones 3,5-dissubstituted has been synthesized with satisfactory yield from the condensation Knoevenagel type between benzaldéhydes and 4-thioxothiazolidin-2-one, 2-thioxothiazolidin-4-one and 1-méthyl-2-thioxoimidazolidin-4-one compounds following by N-alkylation with aryl or acyl halides. The physico-chemical properties of the 5-benzylidene-3-[2-(4-chlorophenyl)-2-oxoethyl]-2 (or 4)-thioxothiazolidin-4 (or 2)-ones and 5-benzylidene-1-methyl-2-thioxoimidazolidin-4-ones synthesized have been described.

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Synthesis and physico-chemical properties of 3-(4-bromobenzyl)-, 3-(4-chlorobenzyl)-5-arylidene-thiazolidine-2,4-diones and 3-(4-chlorobenzyl)-4-thioxo-5-arylidene-thiazolidin-2- ones are described. Twelve new products were synthesized by the aldolisation-crotonisation reaction from aromatic aldehydes and N-alkylated thiazolidinediones or thioxothiazolidinones. Seven compounds were preliminary tested for their bacteriostatic activity.

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Previous studies have shown that Biomphalaria glabrata contains a complete cellulolytic system which includes an endoglucanase, an exoglucanase and a beta-glucosidase. In the present report, a scheme for the purification of the endoglucanase from this invertebrate is proposed. Two major problems were encountered during the study: 1) the presence of a green-brownish pigment, which could not be eliminated by thermal shock or ammonium sulfate precipitation and 2) relative instability of enzymatic activity. Various alternatives were tested and the best sequence of steps was: 1) a sample of the crude extract, obtained by homogenization of the digestive glands in 50 mM Tris-HCl buffer, pH 8.4, and ultracentrifugation, was applied to a Q-Sepharose FPLC column (50 mM Tris-HCl buffer, pH 8.4; 10 mm x 22.2 cm column; flow rate 1.5 ml/min; 0.1 to 0.5 M NaCl gradient); 2) the eluate peak containing activity was dialyzed, lyophilized and eluted from a Superdex-75 gel filtration FPLC column (50 mM ammonium acetate buffer, pH 4.8; 16 mm x 60 cm column; flow rate 1.0 ml/min). A low degree of purification (about 36-fold) and recovery (about 12%) were observed, probably due to enzyme instability. SDS-electrophoresis of the active fraction showed a major peak of 30 kDa. In order to improve the purification scheme, further studies are required to stabilize this enzyme during purification and storage.

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Previous studies have shown that Biomphalaria glabrata contains a complete cellulolytic system which includes an endoglucanase, an exoglucanase and a ß-glucosidase. In the present report, a scheme for the purification of the endoglucanase from this invertebrate is proposed. Two major problems were encountered during the study: 1) the presence of a green-brownish pigment, which could not be eliminated by thermal shock or ammonium sulfate precipitation and 2) relative instability of enzymatic activity. Various alternatives were tested and the best sequence of steps was: 1) a sample of the crude extract, obtained by homogenization of the digestive glands in 50 mM Tris-HCl buffer, pH 8.4, and ultracentrifugation, was applied to a Q-Sepharose FPLC column (50 mM Tris-HCl buffer, pH 8.4; 10 mm x 22.2 cm column; flow rate 1.5 ml/min; 0.1 to 0.5 M NaCl gradient); 2) the eluate peak containing activity was dialyzed, lyophilized and eluted from a Superdex-75 gel filtration FPLC column (50 mM ammonium acetate buffer, pH 4.8; 16 mm x 60 cm column; flow rate 1.0 ml/min). A low degree of purification (about 36-fold) and recovery (about 12 percent) were observed, probably due to enzyme instability. SDS-electrophoresis of the active fraction showed a major peak of 30 kDa. In order to improve the purification scheme, further studies are required to stabilize this enzyme during purification and storage

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Bacterial invasiveness and immunological responses were studied in germfree (GF) and conventional (CV) mice infected with Salmonella typhimurium. Bacterial counts of homogenates prepared from liver and spleen showed that the colony forming units (CFU) increased rapidly in GF mice and reached lethal proportions (10(9) cell per organ) by day 6. In CV mice, these counts increased to about 10(4.5) log cell per organ by day 6 and then declined slowly. An increase in serotype-specific IgM and IgG levels was noted in CV mice with a maximum by day 2. Very low values of these IgM and IgG were observed in GF mice during the course of infection. Delayed type hypersensitivity (DTH) response as measured by footpad swelling was higher in CV animals. Higher hypersensitivity to LPS during infection in GF animals resulted in death of all the animals tested for DTH after day 2. The data obtained suggest that during a rapid invasive bacterial infection, the slow development of immune response of GF mice may result in death of these animals.

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