773 research outputs found
Spatial flocking: Control by speed, distance, noise and delay
Fish, birds, insects and robots frequently swim or fly in groups. During
their 3 dimensional collective motion, these agents do not stop, they avoid
collisions by strong short-range repulsion, and achieve group cohesion by weak
long-range attraction. In a minimal model that is isotropic, and continuous in
both space and time, we demonstrate that (i) adjusting speed to a preferred
value, combined with (ii) radial repulsion and an (iii) effective long-range
attraction are sufficient for the stable ordering of autonomously moving agents
in space. Our results imply that beyond these three rules ordering in space
requires no further rules, for example, explicit velocity alignment, anisotropy
of the interactions or the frequent reversal of the direction of motion,
friction, elastic interactions, sticky surfaces, a viscous medium, or vertical
separation that prefers interactions within horizontal layers. Noise and delays
are inherent to the communication and decisions of all moving agents. Thus,
next we investigate their effects on ordering in the model. First, we find that
the amount of noise necessary for preventing the ordering of agents is not
sufficient for destroying order. In other words, for realistic noise amplitudes
the transition between order and disorder is rapid. Second, we demonstrate that
ordering is more sensitive to displacements caused by delayed interactions than
to uncorrelated noise (random errors). Third, we find that with changing
interaction delays the ordered state disappears at roughly the same rate,
whereas it emerges with different rates. In summary, we find that the model
discussed here is simple enough to allow a fair understanding of the modeled
phenomena, yet sufficiently detailed for the description and management of
large flocks with noisy and delayed interactions. Our code is available at
http://github.com/fij/flocComment: 12 pages, 7 figure
Trust is a Process
Abstract
The paper briefly overviews the growing literature on ‘trust’ and proposes a new definition. The authors define Trust as a process, as a verb, as action that enables the individual to be pro active in improving relationships. The Relationship Audit is described as a tested aid to monitor different aspects of working with others inside and outside the organisation
Choices and Responsibilities: A Human Centric Approach to University-Industry Knowledge Transfer
The paper reflects on the growing complexities of management education in which business practitioners invite selected academic institutions to develop partnerships for resolving practical challenges and equipping those in the workplace to make more reflective and enlightened choices. European examples from Cambridge and Nottingham illustrate that successful industry and academic collaborations embody long-established themes of mentor-mentee, master-learner relationships. This human centric approach yields personal characteristics for reflective practitioners which enhance innovation, productivity and reputation building. The examples presented in this paper are then placed in a broader university – industry knowledge transfer context, using a so-called ‘bow tie’ model.
The authors believe that by shifting the attention from processes to people, from productivity to individual and collective growth and maturity, and by starting to apply the best practices of our human heritage we can make a difference. It is the responsibility of all stakeholders of education to support and contribute to this shift
Scientometrics: Untangling the topics
Measuring science is based on comparing articles to similar others. However,
keyword-based groups of thematically similar articles are dominantly small.
These small sizes keep the statistical errors of comparisons high. With the
growing availability of bibliographic data such statistical errors can be
reduced by merging methods of thematic grouping, citation networks and keyword
co-usage.Comment: 2 pages, 2 figure
Patterns of gene expression in schistosomes: localization by whole mount in situ hybridization
rom the identification of genes to the characterization of their functions and interactions. Developmental biologists have long used whole mount in situ hybridization (WISH) to determine gene expression patterns, as a vital tool for formulating and testing hypotheses about function. This paper describes the application of WISH to the study of gene expression in larval and adult schistosomes. Fixed worms were permeablized by proteinase K treatment for hybridization with digoxygenin-labelled RNA probes, with binding being detected by alkaline phosphatase-coupled anti-digoxygenin antibodies, and BM Purple substrate. Discrete staining patterns for the transcripts of the molecules Sm29, cathepsin L, antigen 10.3 and chorion were observed in the tegument cell bodies, gut epithelium, oesophageal gland and vitelline lobules, respectively, of adult worms. Transcripts of the molecules SGTP4, GP18-22 and cathepsin L were localized to tegument cell bodies and embryonic gut, respectively, of lung schistosomula. We also showed that Fast Red TR fluorescent substrate can refine the pattern of localization permitting use of confocal microscopy. We believe that method of WISH will find broad application, in synergy with other emerging post-genomic techniques, such as RNA interference, to studies focused at increasing our molecular understanding of schistosomes
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