Photonic-Enabled Microwave and Terahertz Communication Systems

Abstract: An optical heterodyne technique for generating millimetre-wave and THz carriers with high spectral purity and low phase noise is described, for application to Gb/s wireless communications systems. Progress on key integrated optical components is reported. Introduction Microwave photonics research [1] has found applications in areas as diverse as electronic warfare and medical imaging, and the development of wireless-over-fibre systems for distribution of cellular radio and other wireless signals within large buildings and other areas where coverage from conventional hill-top sites is poor, has proved to be of considerable commercial importance, with sales of systems reaching some $250 m annually. Now, with wireless local area networks (LANs) ubiquitous and demand for higher wireless transmission rates using IEEE 802.16 and similar standards growing, new potential applications for photonics in wireless communications are emerging, to generate, modulate and detect signals at higher carrier frequencies (>60 GHz) that can support Gb/s data rate

Eureka and beyond: mining's impact on African urbanisation

This collection brings separate literatures on mining and urbanisation together at a time when both artisanal and large-scale mining are expanding in many African economies. While much has been written about contestation over land and mineral rights, the impact of mining on settlement, notably its catalytic and fluctuating effects on migration and urban growth, has been largely ignored. African nation-states’ urbanisation trends have shown considerable variation over the past half century. The current surge in ‘new’ mining countries and the slow-down in ‘old’ mining countries are generating some remarkable settlement patterns and welfare outcomes. Presently, the African continent is a laboratory of national mining experiences. This special issue on African mining and urbanisation encompasses a wide cross-section of country case studies: beginning with the historical experiences of mining in Southern Africa (South Africa, Zambia, Zimbabwe), followed by more recent mineralizing trends in comparatively new mineral-producing countries (Tanzania) and an established West African gold producer (Ghana), before turning to the influence of conflict minerals (Angola, the Democratic Republic of Congo and Sierra Leone)

Turning collegial governance on its head : symbolic violence, hegemony and the academic board

This article draws on Bourdieu’s theorisation of domination and Gramsci’s notions of hegemony within the context of a larger empirical study of Australian university academic governance, and of academic boards (also known as academic senates or faculty senates) in particular. Reporting data that suggest a continued but radically altered form of collegial governance in which hegemony is exercised by management rather than by the professor, it theorises the domination of academic boards within western democratic universities. However, traditional collegial governance is also dependent upon a community of scholars, a role historically played by the academic board. In view of the suggested transition in collegial governance and the resultant convergence of academic work and management, the article concludes with questions about whether academic boards can continue to serve as communities of scholars in future

Quantum dash mode-locked lasers for millimeter wave signal generation and transmission

In this paper we present the remarkable characteristics of quantum dash mode-locked lasers and how they could be used for low phase noise signal generation, for high data rate wireless transmission and radar in the millimeter wave frequency range

The mEPN scheme: an intuitive and flexible graphical system for rendering biological pathways

<p>Abstract</p> <p>Background</p> <p>There is general agreement amongst biologists about the need for good pathway diagrams and a need to formalize the way biological pathways are depicted. However, implementing and agreeing how best to do this is currently the subject of some debate.</p> <p>Results</p> <p>The modified Edinburgh Pathway Notation (mEPN) scheme is founded on a notation system originally devised a number of years ago and through use has now been refined extensively. This process has been primarily driven by the author's attempts to produce process diagrams for a diverse range of biological pathways, particularly with respect to immune signaling in mammals. Here we provide a specification of the mEPN notation, its symbols, rules for its use and a comparison to the proposed Systems Biology Graphical Notation (SBGN) scheme.</p> <p>Conclusions</p> <p>We hope this work will contribute to the on-going community effort to develop a standard for depicting pathways and will provide a coherent guide to those planning to construct pathway diagrams of their biological systems of interest.</p

From the Shell-shocked Soldier to the Nervous Child: Psychoanalysis in the Aftermath of the First World War

This article investigates the development of child analysis in Britain between the wars, as the anxious child succeeded the shell-shocked soldier as a focus of psychoanalytic enquiry. Historians of psychoanalysis tend to regard the Second World War as a key moment in the discovery of the ‘war within’ the child, but it was in the aftermath of the First War that the warring psyche of the child was observed and elaborated. The personal experience of war and its aftermath, and the attention given to regression in the treatment of war neuroses, encouraged Melanie Klein, Anna Freud and others to turn their attention to children. At the same time, however, the impact of the First World War as a traumatic event, with inter-generational consequences, remained largely unaccounted for within psychoanalysis as Klein and others focused on the child's riven internal world

Unhealthy Gambling Amongst New Zealand Secondary School Students: An Exploration of Risk and Protective Factors

This study sought to determine the prevalence of gambling and unhealthy gambling behaviour and describe risk and protective factors associated with these behaviours amongst a nationally representative sample of New Zealand secondary school students (n = 8,500). Factor analysis and item response theory were used to develop a model to provide a measure of ‘unhealthy gambling’. Logistic regressions and multiple logistic regression models were used to investigate associations between unhealthy gambling behaviour and selected outcomes. Approximately one-quarter (24.2 %) of students had gambled in the last year, and 4.8 % had two or more indicators of unhealthy gambling. Multivariate analyses found that unhealthy gambling was associated with four main factors: more accepting attitudes towards gambling (pp = 0.0061); being worried about and/or trying to cut down on gambling (p p = 0.0009). Unhealthy gambling is a significant health issue for young people in New Zealand. Ethnic and social inequalities were apparent and these disparities need to be addressed

Safety and Immunogenicity of an HIV Adenoviral Vector Boost after DNA Plasmid Vaccine Prime by Route of Administration: A Randomized Clinical Trial

In the development of HIV vaccines, improving immunogenicity while maintaining safety is critical. Route of administration can be an important factor.This multicenter, open-label, randomized trial, HVTN 069, compared routes of administration on safety and immunogenicity of a DNA vaccine prime given intramuscularly at 0, 1 and 2 months and a recombinant replication-defective adenovirus type 5 (rAd5) vaccine boost given at 6 months by intramuscular (IM), intradermal (ID), or subcutaneous (SC) route. Randomization was computer-generated by a central data management center; participants and staff were not blinded to group assignment. The outcomes were vaccine reactogenicity and humoral and cellular immunogenicity. Ninety healthy, HIV-1 uninfected adults in the US and Peru, aged 18-50 were enrolled and randomized. Due to the results of the Step Study, injections with rAd5 vaccine were halted; thus 61 received the booster dose of rAd5 vaccine (IM: 20; ID:21; SC:20). After the rAd5 boost, significant differences by study arm were found in severity of headache, pain and erythema/induration. Immune responses (binding and neutralizing antibodies, IFN-γ ELISpot HIV-specific responses and CD4+ and CD8+ T-cell responses by ICS) at four weeks after the rAd5 booster were not significantly different by administration route of the rAd5 vaccine boost (Binding antibody responses: IM: 66.7%; ID: 70.0%; SC: 77.8%; neutralizing antibody responses: IM: 11.1%; ID: 0.0%; SC 16.7%; ELISpot responses: IM: 46.7%; ID: 35.3%; SC: 44.4%; CD4+ T-cell responses: IM: 29.4%; ID: 20.0%; SC: 35.3%; CD8+ T-cell responses: IM: 29.4%; ID: 16.7%; SC: 50.0%.)This study was limited by the reduced sample size. The higher frequency of local reactions after ID and SC administration and the lack of sufficient evidence to show that there were any differences in immunogenicity by route of administration do not support changing route of administration for the rAd5 boost.ClinicalTrials.gov NCT00384787