Integration of a microprobe into a CMM

Various microprobes have been developed in the last decade to address the needs of micrometrology. However, most microprobes are only employed in specialized measuring machines located in a few research institutes and are not widespread in the industry. This work aims to extend the capabilities of conventional coordinate measuring machines (CMMs) towards measuring microgeometries through the low-cost integration of a tactile microprobe. In order to demonstrate this, a gear measuring instrument (GMI), which is a commercial CMM not specialized for measurements at the microscale, has been equipped with a recently developed silicon-membrane-based microprobe. In the first part of this work, the working principle of the microprobe, its assembly and its integration into the GMI are described. Two different mounting setups of the microprobe onto the GMI were evaluated and tested. Measurements on the GMI were performed solely with the microprobe or by combining the microprobe and the measurement system already present on the GMI. This combination makes it possible to use the microprobe advantageously and to exchange it in a comfortable semi-automatic way. To test these two mounting setups, a new involute scanning artifact (SAFT) with superimposed waviness was measured

Integration of an isotropic microprobe and a microenvironment into a conventional CMM

This paper describes the experimental verification of the novel IMT-PTB microprobe combined with a uniquely designed microenvironment. The microprobe consists of three silicon-based parallelograms stacked orthogonally, which leads to high isotropy. The probe tip deflections are detected in 3D with the help of piezoresistors placed in the parallelograms. The microenvironment facilitates and improves the measurement of workpieces with submillimeter features. The new microprobe and the microenvironment were integrated into a commercial coordinate measuring machine (CMM). To evaluate the microprobe performance, PTB produced and calibrated three reference objects: a cube, a sphere, and a microgear measurement standard. The differences between the calibration values and the measurement results obtained by the microprobe were in the sub-micrometer range. Furthermore, the microprobe was compared with the standard probing system of the gear measuring machine by measuring the reference objects with identical parameters. The results show the excellent performance of the micro probing system, thereby extending the capability of the CMM for high-precision measurements of complex workpieces at the microscale

Third Report on Chicken Genes and Chromosomes 2015

Following on from the First Report on Chicken Genes and Chromosomes [Schmid et al., 2000] and the Second Report in 2005 [Schmid et al., 2005], we are pleased to publish this long-awaited Third Report on the latest developments in chicken genomics. The First Report highlighted the availability of genetic and physical maps, while the Second Report was published as the chicken genome sequence was released. This report comes at a time of huge technological advances (particularly in sequencing methodologies) which have allowed us to examine the chicken genome in detail not possible until now. This has also heralded an explosion in avian genomics, with the current availability of more than 48 bird genomes [Zhang G et al., 2014b; Eöry et al., 2015], with many more planned

[Avian cytogenetics goes functional] Third report on chicken genes and chromosomes 2015

High-density gridded libraries of large-insert clones using bacterial artificial chromosome (BAC) and other vectors are essential tools for genetic and genomic research in chicken and other avian species... Taken together, these studies demonstrate that applications of large-insert clones and BAC libraries derived from birds are, and will continue to be, effective tools to aid high-throughput and state-of-the-art genomic efforts and the important biological insight that arises from them

Individual personality does not predict learning performance in a foraging context in female guppies, Poecilia reticulata.

Considerable interindividual variation in behaviour, including learning ability and personality, exists within populations. Recent research has suggested that these two traits might covary; that is, the expression of certain personality traits might be correlated with learning ability. We experimentally tested this hypothesis under controlled laboratory conditions using female Trinidadian guppies. We tested for individual learning performance, measured as time to learn an association between a physical object and the presentation of food, both without (individual learning) and with (social learning) public information from conspecifics. Further, we quantified three ecologically relevant personality traits in individual fish in a fixed sequence: namely, exploration of a novel environment, sociability as the tendency to associate socially with conspecifics and boldness in the face of a simulated threat of predation. Each of these three personality traits was significantly repeatable, but they were not intercorrelated (i.e. did not form a behavioural syndrome). Individuals that needed fewer trials to feed from the objects initially had a higher probability of reaching the learning criterion and needed fewer trials to do so, but this learning performance was not related to repeatable personality traits across individuals. More exploratory individuals tended to learn faster during individual learning. When excluding individuals that had not learned, more social individuals were significantly faster at associative learning during social learning than less social individuals. Overall, we found no compelling evidence for any link between individual personality traits and learning performance, nor between the two modes of learning. Our results therefore suggest that individual personality does not predict learning performance and the observed independence of the two modes of learning tested suggests a lack of a domain-general learning capacity in female Trinidadian guppies, at least under our experimental conditions