13 research outputs found
Construction and characterization of a BAC-library for a key pollinator, the bumblebee Bombus terrestris L
Abstract.: The primitively social bumblebee Bombus terrestris is an ecological model species as well as an important agricultural pollinator. As part of the ongoing development of genomic resources for this model organism, we have constructed a publicly available bacterial artificial chromosome (BAC) library from males of a field-derived colony. We have shown that this library has a high coverage, which allows any particular sequence to be retrieved from at least one clone with a probability of 99.7%. We have further demonstrated the library's usefulness by successfully screening it with probes derived both from previously described B. terrestris genes and candidate genes from another bumblebee species and the honeybee. This library will facilitate genomic studies in B. terrestris and will allow for novel comparative studies in the social Hymenopter
Tibialis posterior in health and disease: a review of structure and function with specific reference to electromyographic studies
Tibialis posterior has a vital role during gait as the primary dynamic stabiliser of the medial longitudinal arch; however, the muscle and tendon are prone to dysfunction with several conditions. We present an overview of tibialis posterior muscle and tendon anatomy with images from cadaveric work on fresh frozen limbs and a review of current evidence that define normal and abnormal tibialis posterior muscle activation during gait. A video is available that demonstrates ultrasound guided intra-muscular insertion techniques for tibialis posterior electromyography
Scientific note on microsatellite DNA analyses revealing diploid and haploid drones in bumblebee mass breeding
Proprotor–wing aerodynamic interaction in the first stages of conversion from helicopter to aeroplane mode
Tiltrotors have the potential to revolutionise air transportation since they combine the flight performance of aeroplanes with the versatility of helicopters. One of the most crucial features characterising tiltrotors is represented by the aerodynamic interaction between wing and rotor. Although this phenomenon has been largely studied using both experiments and calculation, analyses were mainly focused on helicopter operative mode and hovering condition. The present work is aimed at describing the effects due to the aerodynamic interference between wing and rotor of a tiltrotor aircraft employing the tiltwing concept solution during the first stage of the conversion manoeuvre from helicopter to aeroplane configuration. Experimental tests carried out in the open test section of the Politecnico di Milano Large Wind Tunnel with a half-span scaled powered model are reported in detail and results are illustrated in terms of rotor performance and wing aerodynamic loads. Both isolated rotor and half-span model test results are presented as function of several parameters. Overall aircraft performance during the first part of the conversion manoeuvre is finally discussed