In vivo and in vitro antifungal effect of fungal chitosan nanocomposite edible coating against strawberry phytopathogenic fungi

This study compared the effectiveness of fungal chitosan nanocomposite, chitosan gel and chitosan nanoparticles against strawberry phytopathogenic fungi (Botrytis cinerea; Rhizopus stolonifer and Aspergillus niger). Nanoparticles were prepared by ionic gelation method and characterised by dynamic light scattering and scanning electron microscopy. The influence of the edible coatings on fungal growth was analysed in vitro and in vivo The fungal chitosan nanoparticles presented an average size = 331.1 nm (±7.21) with a narrow size distribution (PDI = 0.377) and a zeta potential = +34 mV. The edible coating made by the nanocomposite exhibited important changes in fungal morphology, and the best control of the growth of the assayed fungal strains in artificially infected strawberries. Therefore, nanotechnology brought some benefits to the conventional chitosan gel edible coating, improving its antifungal activity and forming a new eco-friendly coating.     

Sloths (Bradypus variegatus) as a polygastric mammal

Fermentative herbivorous animals have peculiar conformations of the digestive system. It is known that B. variegatus obtained the capacity for evolutionary adaptation, due to their ecology and eating habits. However, despite the literature on feeding management for this species, there is a lack of published information regarding its gastric morphology, and such information would support a better understanding on the diet and digestion of these individuals. We found seven gastric compartments, which histologically revealed three distinct patterns: an aglandular keratinized fraction (mechanical stomach) and two glandular fractions, one a mucus secretor and the other one composed of acid secreting cells (chemical stomach). With these evidences we understand that these individuals have gastric resemblance to ruminants, with some inherent peculiarities of this species, including the transit of the bolus.     

Experimental evaluation of different strengthening techniques of traditional timber connections

A series of monotonic and cyclic tests were performed on unstrengthened specimens, in order to characterize the original behavior of connections, representative of traditional timber trusses. Subsequently, connections strengthened with metal devices were tested under monotonic and cyclic loading. Test data of original connections has been gathered with the purpose of characterizing their behavior, in particular, the post-elastic response and the failure mode. Observing the behavior of strengthened connections under cyclic loading gave straight indications on the positive and negative characteristics of the different strengthening techniques analyzed.     

Kairomonal Response of Predators to Three Pine Bast Scale Sex Pheromones

The kairomonal activity of the sex pheromones of three pine bast scales, Matsucoccus feytaudi, Matsucoccus josephi, and Matsucoccus matsumurae, as well as a new analog of the M. feytaudi sex pheromone, were investigated in pine forests of France, Portugal, and Italy. The response of the maritime pine bast scale predators, Elatophilus spp. and Hemerobius stigma, was used to test the influence of trapping methods, kairomone composition, and dose. Both predators showed significant attraction to all compounds except to the sex pheromone of M. josephi. Significant increase in captures was observed as a function of dose, and within the studied dose range, up to 2200 μg, no threshold saturation limits were observed for any of the attractive compounds. Trap design and size did not significantly influence predator captures, except for high population levels of Elatophilus crassicornis, when plate traps were more efficient than delta traps. Geographic variations were found in the kairomonal responses patterns of both predators, with the M. matsumurae sex pheromone being more attractive to the oriental populations from Corsica and Italy, whereas the western populations in Aquitaine and Portugal were more attracted to the M. feytaudi sex pheromone.     

Comparative study of ZnO thin films prepared by plasma deposition and electron beam evaporation for use in photovoltaic devices

Undoped zinc oxide thin films were grown at room temperature using two techniques: plasma deposition (PD) and electron beam evaporation in an argon atmosphere. PD offers some advantages, such as low ion damage and low deposition temperature. The optical transmittance of the films deposited by both methods was higher than 80% in the near UV–VIS range; the energy band gap and index of refraction agree with values reported in the literature. The resistivity of films grown by PD was 3.1 × 10⁻² Ω cm, lower than the value of 1.2 × 10⁻¹ Ω cm found for plasma assisted e‐beam evaporated films. Copyright © 2010 John Wiley & Sons, Ltd.