Collective Cell Migration: Leadership, Invasion and Segregation

A number of biological processes, such as embryo development, cancer metastasis or wound healing, rely on cells moving in concert. The mechanisms leading to the emergence of coordinated motion remain however largely unexplored. Although biomolecular signalling is known to be involved in most occurrences of collective migration, the role of physical and mechanical interactions has only been recently investigated. In this paper, a versatile framework for cell motility is implemented in-silico in order to study the minimal requirements for the coordination of a group of epithelial cells. We find that cell motility and cell-cell mechanical interactions are sufficient to generate a broad array of behaviours commonly observed in vitro and in vivo. Cell streaming, sheet migration and susceptibility to leader cells are examples of behaviours spontaneously emerging from these simple assumptions, which might explain why collective effects are so ubiquitous in nature. This analysis provides also new insights into cancer metastasis and cell sorting, suggesting in particular that collective invasion might result from an emerging coordination in a system where single cells are mechanically unable to invade.

Pathogens after shrimp: A rogue's gallery of the industry's four most destructive adversaries

The paper discusses the four most destructive shrimp pathogens, such as MBV, the monodon baculovisrus, IHHNV, the infectious hypodermal and hematopoietic necrosis virus, Vibrio harveyi, the luminous bacteria, and WSBV, the white spot syndrome-associated baculovirus. The effects, detection method and treatment for the four pathogens were also briefly discussed.

Graduate Education for Leadership in Sustainable Development Innovation , Practice and Research

This paper reflects on the motivation, method and effectiveness of teaching leadership and organisational change to graduate engineers. Delivering progress towards sustainable development requires engineers who are aware of pressing global issues (such as resource depletion, climate change, social inequity and an interdependent economy) since it is they who deliver the goods and services that underpin society within these constraints. In recognition of this fact the Cambridge University MPhil in Engineering for Sustainable Development has focussed on educating engineers to become effective change agents in their professional field with the confidence to challenge orthodoxy in adopting traditional engineering solutions. This paper reflects on ten years of delivering this course to review how teaching change management and leadership aspects of the programme have evolved and progressed over that time. As the students on this professional practice have often extensive experience as practising engineers and scientists, they have learned the limitations of their technical background when solving complex problems. Students often join the course recognising their need to broaden their knowledge of relevant cross-disciplinary skills. The course offers an opportunity for these early to mid-career engineers to explore an ethical and value-based approach to bringing about effective change in their particular sectors and organisations. This is achieved through action learning assignments in combination with reflections on the theory of change to enable students to equip themselves with tools that help them to be effective in making their professional and personal life choices. This paper draws on feedback gathered from students during their participation on the course and augments this with alumni reflections gathered some years after their graduation. These professionals are able to look back on their experience of the taught components and reflect on how they have been able to apply this key learning in their subsequent careers.

Dynamic technology leadership: The adaptive role of the CTO

OVERVIEW: The importance of the chief technology officer role is widely accepted, particularly in today's turbulent, global conditions. However, not enough is known about the key activities of CTOs or the factors that influence their priorities. Thirty in-depth interviews conducted with the CTOs in global firms identified key activities: aligning technology and corporate strategy and business models, determining technology entry and exit points, and preparing business cases to secure funding for technology development. The research also showed that priority areas for CTOs are related to technology transition points-major contextual and business discontinuities that impact the focus of the CTO. We conclude that the determination of priorities at these technology transition points is highly idiosyncratic and closely related to whether the CTO functions more or less strategically.

Physicians in leadership: the association between medical director involvement and staff-to-patient ratios

In a hospital environment that demands a careful balance between commercial and clinical interests, the extent to which physicians are involved in hospital leadership varies greatly. This paper assesses the influence of the extent of this involvement on staff-to-patient ratios. Using data gathered from 604 hospitals across Germany, this study evidences the positive relationship between a full-time medical director (MD) or heavily involved part-time MD and a higher staff-to-patient ratio. The data allows us to control for a range of confounding variables, such as size, rural/urban location, ownership structure, and case-mix. The results contribute to the sparse body of empirical research on the effect of clinical leadership on organizational outcomes.

Graduate education for leadership and organisational change in sustainable development

This paper reflects on the motivation, method and effectiveness of teaching leadership and organisational change to graduate engineers. Delivering progress towards sustainable development requires engineers who are aware of pressing global issues (such as resource depletion, climate change, social inequity and an interdependent economy) since it is they who deliver the goods and services that underpin society within these constraints. They also must understand how to implement change in the organisations within which they will work. In recognition of this fact the Cambridge University MPhil in Engineering for Sustainable Development has focussed on educating engineers to become effective change agents in their professional field with the confidence to challenge orthodoxy in adopting traditional engineering solutions. This paper reflects on ten years of delivering a special module to review how teaching change management and leadership aspects of the programme have evolved and progressed over that time. As the students who embark on this professional practice have often extensive experience as practising engineers and scientists, many have already learned the limitations of their technical background when solving complex problems. Students often join the course recognising their need to broaden their knowledge of relevant cross-disciplinary skills. The programme offers an opportunity for these early to mid-career engineers to explore an ethical and value-based approach to bringing about effective change in their particular sectors and organisations. This is achieved through action learning assignments in combination with reflections on the theory of change to enable students to equip themselves with tools that help them to be effective in making their professional and personal life choices. This paper draws on feedback gathered from students during their participation on the programme and augments this with alumni reflections gathered some years after their graduation. These professionals are able to look back on their experience of the taught components and reflect on how they have been able to apply this key learning in their subsequent careers. Copyright © 2012 September.

Non-destructive characterization of structural hierarchy within aligned carbon nanotube assemblies

Understanding and controlling the hierarchical self-assembly of carbon nanotubes (CNTs) is vital for designing materials such as transparent conductors, chemical sensors, high-performance composites, and microelectronic interconnects. In particular, many applications require high-density CNT assemblies that cannot currently be made directly by low-density CNT growth, and therefore require post-processing by methods such as elastocapillary densification. We characterize the hierarchical structure of pristine and densified vertically aligned multi-wall CNT forests, by combining small-angle and ultra-small-angle x-ray scattering (USAXS) techniques. This enables the nondestructive measurement of both the individual CNT diameter and CNT bundle diameter within CNT forests, which are otherwise quantified only by delicate and often destructive microscopy techniques. Our measurements show that multi-wall CNT forests grown by chemical vapor deposition consist of isolated and bundled CNTs, with an average bundle diameter of 16 nm. After capillary densification of the CNT forest, USAXS reveals bundles with a diameter 4 m, in addition to the small bundles observed in the as-grown forests. Combining these characterization methods with new CNT processing methods could enable the engineering of macro-scale CNT assemblies that exhibit significantly improved bulk properties. © 2011 American Institute of Physics.

Leadership of healthcare commissioning networks in England: a mixed-methods study on clinical commissioning groups.

To explore the relational challenges for general practitioner (GP) leaders setting up new network-centric commissioning organisations in the recent health policy reform in England, we use innovation network theory to identify key network leadership practices that facilitate healthcare innovation.

Structural analysis of plate-type fuel assemblies and development of a non-destructive method to assess their integrity

This work is concerned with the structural behaviour and the integrity of parallel plate-type nuclear fuel assemblies. A plate-type assembly consists of several thin plates mounted in a box-like structure and is subjected to a coolant flow that can result in a considerable drag force. A finite element model of an assembly is presented to study the sensitivity of the natural frequencies to the stiffness of the plates' junctions. It is shown that the shift in the natural frequencies of the torsional modes can be used to check the global integrity of the fuel assembly while the local natural frequencies of the inner plates can be used to estimate the maximum drag force they can resist. Finally a non-destructive method is developed to assess the resistance of the inner plates to bear an applied load. Extensive computational and experimental results are presented to prove the applicability of the method presented. © 2013 Elsevier B.V. All rights reserved.