This paper describes the finite element method using ABAQUS to model the axial compressive behaviour of inclined, tapered and straight-tapered-straight (STS) concrete filled steel tubular stub (CFST) columns with square hollow sections. The accuracy of the numerical model was verified by comparing the numerical predictions with experimental study of the 200×200×3.75 RHS filled with C60 concrete with inclined angle of 0-9° and tapered angle of 0-4°. The results show that the compressive behaviours, load vs. strain relationship and failure mode predicted by the numerical simulations were agreeable with experimental results. After the validation, a parametric study was performed with 3 typical steel hollow sections (200×200×3.75 RHS, 300×300×6.3 RHS and 400×400×8.0 RHS) and extended the inclined angle and tapered angle to 0-15° and 0-12° respectively. The parametric study highlights some of the behaviour observed in test and extends the application range. In addition, reduction factor for calculating the axial capacity of this form of CFST columns are proposed.

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No / Nowhere in the world is the demand for peace more prominent and challenging than in Africa. From state collapse and anarchy in Somalia to protracted wars and rampant corruption in the Congo; from bloody civil wars and extreme poverty in Sierra Leone to humanitarian crisis and authoritarianism in Sudan, the continent is the focus of growing political and media attention. This book presents the first comprehensive overview of conflict and peace across the continent. Bringing together a range of leading academics from Africa and beyond, "Peace and Conflict in Africa" is an ideal introduction to key themes of conflict resolution, peacebuilding, security and development. The book's stress on the importance of indigenous Africa approaches to creating peace makes it an innovative and exciting intervention in the field.

No / This volume critically examines what happens when war formally ends, the difficult and complex challenges and opportunities for winning the peace and reconciling divided communities. By reviewing a case study of the West African state of Sierra Leone, potential lessons for other parts of the world can be gained. Sierra Leone has emerged as a 'successful' model of liberal peacebuilding that is now popularly advertised and promoted by the international community as a powerful example of a country that they finally got right. Concerns about how successful a model Sierra Leone actually is, are outlined in this project. As such this volume: provides a critical understanding of the nature, dynamics and complexity of post-war peacebuilding and development from an internal perspective; critically assesses the role and contribution of the international community to state reconstruction and post-war peacebuilding and evaluates what happens when war ends; and explores the potential relevance and impact of comparative international efforts of post-war state building and reconstruction in other parts of Africa and the world. The collection focuses not only on understanding the root causes of conflict but also identifying and appreciating the possibilities and opportunities for peace. The lessons found in this book resonate well beyond the borders of Sierra Leone and Africa in general.

No description available.

Concrete-filled steel tubes are gaining increasing prominence in a variety of engineering structures, with the principal cross-section shapes being square, rectangular and circular hollow sections. A recent addition to this range has been that of elliptical hollow sections. The structural response of empty elliptical tubes has been examined in previous studies. In this paper, the cross-sectional axial behaviour of concrete-filled elliptical hollow sections is investigated. An experimental programme comprising a total of 21 test specimens, with three nominal tube thicknesses (4 mm, 5 mm and 6.3 mm) and three concrete grades (C30, C60 and C100) has been performed. The effects of steel tube thickness, concrete strength and constraining factor on elastic stiffness, ductility and ultimate strength were studied. To simulate the effects of concrete shrinkage, the inner surfaces of 6 of the 21 test specimens were coated with grease prior to casting. To investigate confinement effects, a further 6 of the 21 test specimens were loaded through the concrete core only. The results of the tests presented herein were combined with those from previous studies, and compared with existing design provisions for square, rectangular and circular concrete-filled tubes. The design expressions from current European, North American, Japanese, British and Chinese Standards were assessed. On the basis of the comparisons, design recommendations for concrete-filled elliptical hollow sections have been made.

No / This paper presents experimental results of temperature distribution in fire in four typical types of steel-concrete composite joint (web cleat, fin plate, flush endplate and flexible endplate) with different fire-protection schemes. The test specimens were unloaded and the steelwork of each joint assembly was exposed to a standard fire condition [ISO 834, 1975: Fire Resistance Tests, Elements of Building Construction, International Organization for Standardization, Geneva] in a furnace. In total, 14 tests were conducted, including 4 tests without any fire protection and 10 tests with different schemes of fire protection. The main objective of these tests was to investigate the effects of three practical fire-protection schemes as alternatives to full fire protection of the entire joint assembly. The three alternative methods of fire protection were: (1) protecting a segment, instead of the entire length, of the beams; (2) unprotected bolts and (3) protecting the columns only. The main results of these tests are: (1) if all the steel work (excluding the bolts) in the joint assembly was protected, whether or not protecting the bolts had very little effect on temperatures in the protected steelwork other than the bolts. The bolt temperatures were higher if they were not protected than if they were protected, but the unprotected bolt temperatures in a joint with fire protection to other steelwork were much lower than bolt temperatures in a totally unprotected joint; (2) as far as joint temperatures are concerned, protecting a segment of 400 mm of the beam was sufficient to achieve full protection and (3) if only the column was protected, only the joint components that were in the immediate vicinity of the column (such as welds) developed noticeably lower temperatures than if the joint assembly was unprotected, but due to heat conduction from the unprotected steel beams, these temperature values were much higher than if the joint assembly was protected. Furthermore, the column temperatures in the joint region were much higher than the protected column temperatures.

A doubly resonant cavity was used to search for nonlinear radiofrequency (RF) energy conversion in a range of biological preparations, thereby testing the hypothesis that living tissue can demodulate RF carriers and generate baseband signals. The samples comprised high-density cell suspensions (human lymphocytes and mouse bone marrow cells); adherent cells (IMR-32 human neuroblastoma, G361 human melanoma, HF-19 human fibroblasts, N2a murine neuroblastoma (differentiated and non-differentiated) and Chinese hamster ovary (CHO) cells) and thin sections or slices of mouse tissues (brain, kidney, muscle, liver, spleen, testis, heart and diaphragm). Viable and non-viable (heat killed or metabolically impaired) samples were tested. Over 500 cell and tissue samples were placed within the cavity, exposed to continuous wave (CW) fields at the resonant frequency (f) of the loaded cavity (near 883 MHz) using input powers of 0.1 or 1 mW, and monitored for second harmonic generation by inspection of the output at 2f. Unwanted signals were minimised using low pass filters (</= 1 GHz) at the input to, and high pass filters (>/= 1 GHz) at the output from, the cavity. A tuned low noise amplifier allowed detection of second harmonic signals above a noise floor as low as -169 dBm. No consistent second harmonic of the incident CW signals was detected. Therefore, these results do not support the hypothesis that living cells can demodulate RF energy, since second harmonic generation is the necessary and sufficient condition for demodulation.

Our purpose is to examine the possibilities of Bakhtinian dialogical analysis for understanding students' experiences of medical training. Twenty-three interviews were conducted with eleven British medical students intercalating in psychology. Forty emotionally resonant key moments were identified for analysis. Our analysis illustrates students' use of the professional genre to present their training as emotionally neutral. However, we show how medical training can be framed in more unofficial and affective-laden ways in which threshold moments of crisis are presented as space-time breaches characteristic of the genres of adventure-wonder and adventure-ordeal. This affect was often depotentiated in the narratives through brief allusion to the professional genre. This cycling between genres suggests that the students were searching for an appropriate way in which to frame their experiences, a central dilemma being the extent to which medical training makes sense within an immediate and affect-laden, or future-orientated and affect-neutral, pedagogy. Finally, we identify how consultants are an important aspect of the affective experience of medical training who, at their best, offer inspiring exemplars of flexible movement between official and unofficial ways of being a doctor. In conclusion, we demonstrate the potential of genres to make sense, and to organize the experience, of medical training spatially in terms of moving between personal and impersonal contact, temporally in terms of moving between the extraordinary and routine, and affectively in terms of moving between potent and neutral affect. Learning to use the professional genre is part of enculturation as a doctor and can be helpful in providing a framework restoring coherence and composure through engaging with, and reformulating, difficult experiences. However, it is important to take seriously the resistance many of the students demonstrated to the professional genre as a possible barometer of its acceptability to the general public.

Two key themes of this special issue are: how violence challenges democracy and how democratic politics might, over time, diminish violence. This paper explores how violence(s) embedded in Latin America's state formation process are multiplied rather than diminished through democratization, generating a securitizing logic which fundamentally distorts democratic principles. Known for its high levels of historic violence(s), Latin America today is second only to Southern Africa in levels of homicide in the world. Some see contemporary violence in the region as a rupture from the past: ‘new violence’ characterized by its urban and social nature in contrast to the rural and political nature of the past. Violence, however, has a reproductive quality, by which it is transmitted through space as well as time. This article argues that rather than reflecting a rupture with the past, violence in Latin America has merely accelerated its complex reproduction in many forms across (gendered) spaces of socialization. The paradox is that the proliferation of this violence has occurred alongside democratic transitions. Although the state is not directly responsible for all the violence which is taking place, this article argues that in many countries it is the very trajectory of the state-formation process which has facilitated this rapid reproduction of violence. I call this process ‘perverse’. Democracy is increasingly subject to the fears and insecurities of the population, enabling the state to build its authority not on the protection of citizens' rights, but on its armed encounters and insidious collusions with violent actors in the name of ‘security provision’. Categories of people become non-citizens, subjected to abuse by state, para-state and non-state violent actors. If this process continues, democracy will ultimately be securitized.