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Clavibacter michiganensis subsp. michiganensis can cause severe losses to tomato crops and new types of alternative control must be identified. Induced resistance is a potential method. Among resistance inducers, the mushrooms Lentinula edodes (Le) and Agaricus subrufescens (Abl) exhibit the potential to be used in plant disease control. The objectives of this study were: (i) evaluate the potential of these mushrooms and of acibenzolar-S-methyl (aSm) to control bacterial canker; (ii) study the mode of action of these materials by measuring defense-relate enzyme activity; (iii) partially purify biologically active molecules. The aqueous extracts from mushroom isolates, as well as aSm, did not inhibit bacterial growth in vitro. However, 10% (v/v) solutions of extracts from the isolates Le-96/17 and Abl-26, as well as aSm, reduced wilt in tomato plants under greenhouse conditions. Plants treated with aSm, Abl-26 and Le-96/17 showed an increase in peroxidase and chitinase. Phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) activities increased with all treatments. Because isolate Le-96/17 induced the greatest wilt reduction, its aqueous extract was precipitated with ammonium sulfate. The fraction at 40-80% saturation was submitted to anion-exchange chromatography (AEC). The AEC fractions 3 and 4, the inducer aSm and the aqueous extract of Le-96/17 reduced the bacterial disease. The fractions 3 and 4, the 40-80% precipitate and the aqueous extract from Le-96/17 contained more than one protein band. In conclusion, the isolate Le-96/17 induced resistance to C. michiganensis in tomato and partial purification of the inducer molecules was obtained. [ABSTRACT FROM AUTHOR]

Copyright of Archivos de Medicina Veterinaria is the property of Universidad Austral de Chile, Facultad de Ciencias Veterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archivos de Medicina Veterinaria is the property of Universidad Austral de Chile, Facultad de Ciencias Veterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archivos de Medicina Veterinaria is the property of Universidad Austral de Chile, Facultad de Ciencias Veterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the present study was to compare the effects of using different intensities and types of aerobic exercise (i. e., cycle ergometer or running) during concurrent training on neuromuscular adaptations. A total of 44 young women were randomly assigned to 1 of 4 groups: concurrent strength and continuous running training (SCR, n = 10), concurrent strength and interval running training (SIR, n = 11), concurrent strength and continuous cycle ergometer training (SCE, n = 11), or strength training only (STO, n = 12). Each group trained twice a week during 11 weeks. The following strength measurements were made on all subjects before and after training period: maximal strength (1RM) in knee extension, bench press and leg press exercises; local muscular endurance (number of repetitions at 70% of 1 RM) in knee extension and bench press exercises; and isometric and isokinetic peak torque of knee extension. There were significant increases in the upper and lower-body 1 RM, isometric and isokinetic peak torque in all training groups (p < 0.001), with no differences between groups. The present results suggest that in young women, concurrent training performed twice a week promotes similar neuromuscular adaptations to strength training alone, regardless of the type and the intensity in which the aerobic training is performed. [ABSTRACT FROM AUTHOR]

In this work, an experimental study was performed on the influence of plug-filling, loading rate and temperature on the tensile strength of single-strap (SS) and double-strap (DS) repairs on aluminium structures. Whilst the main purpose of this work was to evaluate the feasibility of plug-filling for the strength improvement of these repairs, a parallel study was carried out to assess the sensitivity of the adhesive to external features that can affect the repairs performance, such as the rate of loading and environmental temperature. The experimental programme included repairs with different values of overlap length (LO = 10, 20 and 30 mm), and with and without plug-filling, whose results were interpreted in light of experimental evidence of the fracture modes and typical stress distributions for bonded repairs. The influence of the testing speed on the repairs strength was also addressed (considering 0.5,5 and 25 mm/min). Accounting for the temperature effects, tests were carried out at room temperature (&ap;23°C), 50 and 80°C. This permitted a comparative evaluation of the adhesive tested below and above the glass transition temperature (Tg), established by the manufacturer as 67°C. The combined influence of these two parameters on the repairs strength was also analysed. According to the results obtained from this work, design guidelines for repairing aluminium structures were recommended. [ABSTRACT FROM AUTHOR]

The article presents a study on the role of neutrolizing antibody (NAb) escape mutants for the maintenance of viral persistence in commercial meat-type chickens. For the study, researchers examined a J avian leukosis virus (ALVJ) molecular clone, ADOL pR5-4. They analyzed the emergence of NAb escape variants through the use of sequential autologous virus neutralization (VN) and heterologous VN. They found that the prevalence of antibody escape variants in chickens contributes to the persistence of ALVJ.

A review is presented of chemical vapour deposition (CVD) diamond coating of silicon nitride (Si[sub 3]N[sub 4]) materials. Microcrystalline and nanocrystalline diamond films were grown using microwave plasma (MPCVD) and hot filament (HFCVD) reactors, respectively. Scanning electron and atomic force microscopy, μ-Raman spectroscopy, low incident angle and classical X-ray diffraction, acoustic emission assisted Brale indentation and thermal conductivity measurements were employed for the full characterisation of the diamond/ Si[sub 3]N[sub 4] system. Using these techniques, the nucleation and growth stages as a function of substrate composition and surface pretreatment were characterised, as well as the diamond quality, the existence of residual stresses and the adhesion between the diamond film and the substrate. Based on this study, a tailored material was developed and tested in the machining of hardmetal workpieces with encouraging results. [ABSTRACT FROM AUTHOR]