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In this work, the industrial sintering response of the commercial aluminum powder metallurgy alloy ‘Alumix 123’ has been examined and the resulting microstructure investigated by optical microscopy, scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction. Alumix 123 is similar in composition to wrought aluminum alloy 2014 and was revealed to develop a sintered density of 92% of theoretical using standard practices for industrial sintering. Microstructural investigations proved that as a result of industrial sintering, a number of embrittling iron-containing intermetallics are developed in addition to the desirable copper-rich intermetallics. To improve the density of sintered components, procedures were developed for secondary processing by ‘sizing’ (repressing) in a laboratory setting. The results showed that sizing to the industry standard reduction in height of 5% only closed a portion of open surface porosity and that higher sizing pressures should be used in applications that are sensitive to this microstructural feature.

Over the last few decades, the concept of the self has come under close scrutiny, from the work of Charles Taylor (The Sources of the Self, 1989) to Christopher Gill (The Structured Self in Helleni...

The objective of this research was to assess the SPS-forge response of fully pre-alloyed aerospace grade 7055 (Al–8Zn–2.1Mg–2.3Cu–0.2Zr) powder. The core variables investigated were the sintering temperature, time, and atmosphere employed, as well as the average particle size and the manner of uni-axial loading. Samples sintered in vacuum at 500°C for 40 min with delayed loading offered the most desirable combination of density, hardness, and bend properties but remained relatively brittle. Hot forging of the sintered preforms was found to impart sizable gains in mechanical properties. The SPS-forge product exhibited tensile yield strength of 603 MPa coupled with a ductility of 9.1% and a hardness of 93 HRB. All such properties were largely equivalent to those measured for the wrought counterpart.

This article offers an explanation for the wide spatial variations in choice of insolvency route by personal debtors across local authorities in England and Wales. It is argued that formal bankruptcy has a more negative impact on social capital through stigma effects than the alternative of Individual Voluntary Arrangements. Consequently, spatial variations in choices are related to variations in social capital. The hypotheses derived from this approach are tested through the use of spatial econometric models utilising data from England and Wales. The results provide support for a positive link between variables related to social capital (age, mobility and home ownership) and choice of IVAs. It is argued that avoidance of stigma costs provides an explanation for the apparent paradox of the significant growth of IVAs despite their high cost to debtors compared to bankruptcy. Whilst there is only limited support for impacts directly related to the urban-rural environment, significant spatial interdependencies in choices across neighbouring areas are also uncovered.

Spatial variations in entrepreneurial activity have been shown to be a time persistent phenomenon in many countries. This paper analyses how these spatial variations have been affected by the recent financial crisis within the context of theories of regional resilience and adaptability. The analysis applies Exploratory Spatial Data Analysis techniques to data on firm births across Local Authority Districts of Great Britain during the period 2004–2012. The results demonstrate that, whilst the overall shape of the spatial distribution of firm births remained persistent, there is evidence of an increase in regional inequality. This is primarily associated with a divergence between London and the rest of the distribution. London, together with part of its surrounding area, appears to constitute a resilient entrepreneurial regime that has generated a dynamic, adaptive response to the crisis with high rates of new firm formation in contrast to other regions which have remained locked into lower rates of...

‘Playful yet serious, expansive yet intimate […] a veritable Eden pregnant with the promise of delight and knowledge’ – as Fayaz S. Alibhai reminds us, gardens in Islam are ‘quintessential represen...

Book review of The Pope and the Professor: Pius IX, Ignaz von Dollinger, and the Quandary of the Modern Age, by Thomas Albert Howard, New York, Oxford University Press, 2017, xx + 339 pp., US$45.00 (hardback), ISBN 978 0 1987 2919 8

Plato’s allegory of the cave provides us with a useful conceptual framework in which to approach the major texts of German Political Thought; in other words, the tradition of German Political Thought is informed at a deep level by the discourse of Platonism. The message of the allegory of the cave is an eminently political one, inasmuch as it encourages the reader to go out into the world and to discover whether it is, in the Greek sense of the word, a kosmos or not. Whether this kosmos involves a model of an Ideal kind (as Plato argued), or remodelling or reshaping the world from within the individual (as the modern world since Romanticism has believed), is the biggest political decision we face in the future.

This chapter contextualizes Plato chronologically and geographically, providing a detailed reading of the allegory of the cave in book 7 of the Republic. The allegory itself provides us with a clue to its political implications: the people in the cave are prisoners; they are sitting there in chains, and while they may think they are free, they are not. These individuals are prisoners who have to be liberated; they have to undertake, literally, a revolution by turning their heads around from the wall of the cave to the fire. For all the mystical connotations in this passage, Plato insists that the dialectic is an essentially rational process, and the state he describes—however odd from a modern perspective—is one ultimately founded on reason.

Despite advances in cancer treatment and prevention, familial cancers remain a leading cause of cancer-related deaths worldwide. Familial cancers, particularly breast, ovarian, and hereditary nonpolyposis colorectal cancer, are a group of complex and heterogeneous tumors which contain germline mutations, complicating their clinical diagnosis and treatment. Recently, genome profiling has emanated as a diagnostic and prognostic tool to assist clinicians in making better decisions in response to therapy. Such approaches identify mutations in the coding, as well as the noncoding (nc) genome, which is now appreciated to impact gene regulation. Current studies have confirmed the involvement of ncRNAs (miRNAs, snRNAs, piRNAs, siRNAs, and snoRNAs) in promoting altered gene expression patterns and the development of cancer. This can be harnessed to develop noninvasive diagnostic tools and novel treatments; indeed, miRNAs can circulate stably in body fluids. In this chapter, we have focused on the discovery, characterization, toxicity, and involvement of ncRNAs in precision medicine for managing and diagnosing familial cancers.

The addition of scandium as the primary alloying element to aluminum alloys has made them useful for aeronautical and automotive industrial applications due to their low inherent density and thermal stability. In the present work, a powder metallurgy approach premised on spark plasma sintering coupled with asymmetric rolling was considered as a means of processing an Al-Sc-Zr alloy. Increasing SPS temperatures were found to promote progressively greater extents of precipitate coarsening coupled with a reduction in strength yet an improvement in ductility. The application of asymmetric rolling improved the properties of all as-sintered products significantly and was particularly beneficial at the lower range of hot rolling temperatures considered. TEM analyses revealed that rolling temperature had negligible effects on the coarsening behavior of pre-existing Al3(Sc,Zr) precipitates in the sintered product, while EBSD studies implied that subgrain strengthening was the primary mechanism underpinning the superior tensile properties measured in the rolled products.

Moving from Kant to Hegel we find many of the central themes of Kantian thought enriched, enhanced, and developed in the work of this great philosopher. His reception has proved remarkably important in the genesis of existentialism, psychoanalysis, and post-structuralism, yet the discourse of Platonism continues to make its subterranean presence felt in Hegel’s political philosophy. His thought has three guiding ideas: first, the principle that “what is rational, is real; and what is real, is rational”; second, the dialectic; and third, his relation to Kant and to Idealism. For Hegel, we must learn to see the world through the eye of reason and, if we do so, we shall see the world from “the sum total of all philosophical perspectives.”

Habermas stands as a symbol of continuity with the Platonic tradition, which operates through dialogue, such as the ones conducted by Socrates and reconstructed by Plato. For Habermas, central to any philosophical activity is a setting he calls the “ideal speech situation,” and this Habermasian notion brings us back to the discourse of Platonism and to the allegory of the cave. First, it returns us to the importance of speech, dialogue, and discourse; second, it is ideal and yet, without it, we cannot be truly rational; third, it highlights the ethical dimension of political theory; and fourth, it reveals a religious dimension to politics. In the famous debate in 2004 between Habermas and Cardinal Ratzinger (later Pope Benedict XVI), the question of religion moves to the fore.

Thanks to Friedrich Schleiermacher, a translator and commentator in Plato, the nineteenth century had seen a revival of interest in Platonism in Germany. If Marx is the totemic thinker for the political Left, Nietzsche is frequently, albeit mistakenly, associated with the political Right. Nietzsche’s correspondence reveals a fundamental ambivalence in his attitude towards Plato, while Heidegger’s relation to the Greeks in general and to Plato in particular helps clarify the relation between the discourse of Platonism and the tradition of German Political Thought. In his lecture course On the Essence of Truth and in his Rectoral Address, Heidegger offers an analysis of the allegory of the cave and discusses Socrates’s remark in the Republic, “all that is great stands in the storm” (497d).

In the course of our discussion of the German tradition in political thought, we shall focus on the following five main themes: the relation between the individual and society; the primacy of the economic; our engagement with the material world; the notion of the contract; and the function of the state. Using these five ideas as “benchmarks” for the thinkers discussed in the pages that follow will help illustrate both the specificities of the thought of each individual thinker as well as the common thread of concerns which, albeit in different ways and in varying degrees, runs through all of them. And the common thread which runs through them is the discourse of Platonism, centered on the famous allegory of the cave in Plato’s Republic.

The sense that the individual human being is both temporal and eternal, phenomenal and noumenal, links Kant with the discourse of Platonism in the German tradition of political thought. Despite the normative (i.e., rule-based) emphasis of Kant’s ethics as compared with the prudential (i.e., virtue-based) emphasis of Plato’s, there are important parallels between Kant and Plato. Although in the “Introduction” to the first Critique Kant initially criticizes Plato, in the “Transcendental Dialectic” of that work Kant expounds his understanding of the Platonic doctrine of the Idea and aligns his critical philosophy with Plato’s metaphysics. In this way Kant activates, using the discourse of Platonism, the important notion of the ideal, in the specific sense that this term is used in German Idealism.

The Frankfurt School emerges from a confluence of three major traditions in German Political Thought, namely Marx, Nietzsche, and Freud. Like the Frankfurt School, all three thinkers believe that reality is usually in some way fundamentally misunderstood, and we must look “behind” the phenomena of society in order to understand what is “really” going on. To use the phrase of Paul Ricœur, they are “masters of suspicion,” and what they offer is something the Frankfurt School sought to make its own—a tradition and technique of critique. At the heart of the allegory of the cave lies a huge suspicion about our ontological and existential delusions, so there is good reason for arguing that the archetypal “master of suspicion” is Plato himself.

Raphael’s painting The School of Athens illustrates in an iconic way the difference in emphasis between the founder of the Academy, Plato, and its most famous pupil, Aristotle. While Plato and Aristotle share a good deal in terms of outlook, their difference of approach is crucial: while Plato begins with the first-order questions (what is justice? what is the Good?), Aristotle begins with what is actually happening on the ground, and builds up his system from there: his method is analytic and genetic. Aristotle discerns six different forms of government, three of which he regards as positive (kingship, aristocracy, constitutional government), three as negative (tyranny, oligarchy, democracy). These six different forms are judged in relation to their performance in delivering the telos of politics, that is, the good life.

The main philosophical context for Marx was the thought of Hegel, which Marx modified in a crucial respect: he removed its idealist perspective. Marx can also, however, be placed in a much longer philosophical tradition, which takes us back to the ancient Greeks, for in his doctoral thesis he engaged with pre-Platonic and post-Platonic thought. The entire thrust of Marx’s argumentation is anti-Platonic, and it cannot be sufficiently emphasized how Marx saw his work as a contribution to the science of economics. For Marx, there is no path out of the cave, for there is nothing outside the cave: rather, the revolutionary politics he and Engels espoused aimed at changing how the prisoners governed themselves, and the Marxist conception of liberation is entirely materialist and immanent.

In this chapter we leap several centuries from Plato and Aristotle to Rousseau, whose thought offers a good point to pick up our analysis of political thought as an attempt to find a way out of the cave described in the allegory in book 7 of the Republic. In the arresting opening lines of Rousseau’s Social Contract, we find ourselves back in the world of Plato’s cave: that is to say, we find ourselves in chains, an image that plays an almost obsessive role in the thought of Rousseau. There are important areas of affinity and agreement between Rousseau and Plato, but there are also some important areas of difference and disagreement too, not least around the roles played by liberty, equality, and sovereignty.

Asymmetric rolling is achieved usually by deforming a material through rollers of the same diameter driven at different velocities or via rollers of different diameters but the same velocity. Asymmetric rolling has become important particularly because it can be used to modify the microstructure and in turn improve the mechanical properties of most materials. This is especially true for various metals such as iron, magnesium and aluminum alloys. The objective of this of this research was to investigate the effects of the core processing parameters of interest (roller velocities, velocity ratio, rolling direction, starting thickness of specimen and extent of reduction) on aluminum alloy AA6061 (Al-0.6Si-1.0 Mg). Experimental findings indicated that ASRed specimens exhibited superior tensile properties to symmetrically rolled counterparts provided that the net reduction was achieved in a minimum number of passes. Conversely, no significant gains were recorded in the mechanical properties due to increases in roller velocities or altering the rolling direction. Comparisons of the resultant microstructures within asymmetrical and conventionally rolled counterparts as assessed through electron back scatter diffraction (EBSD) are also presented. The undeformed base metal revealed the presence of a cubic texture {100} . This texture however evolved into shear {111} and brass {110} texture components in specimens subjected to asymmetric (VR = 2.2) and symmetric rolling respectively.

Metal-matrix composites (MMC) of a 2000-series aluminum alloy coupled with AlN were fabricated through a commercially-relevant aluminum powder metallurgy (APM) approach. Cylindrical preforms containing 0–5 vol% AlN were produced to investigate the mechanical properties and microstructure evolution through hot upset forging. Specimen were deformed to a maximum strain of 0.15–1.55 mm/mm at rates of 0.1–1.0 s−1. TEM observations of forged products indicated the Al–AlN interfaces were free of defects and of high quality. Near-full (>99.5% theoretical) densities were observed at 1.40 mm/mm. At this strain, a substantial increase in all tensile properties was observed. An elastic modulus of 77 GPa was realized in a forged product with 5% AlN, accompanied by a 0.2% offset yield strength of 325 MPa and a UTS of at least 400 MPa. Versus an undeformed sample, forged MMC’s exhibited up to a five-fold increase in tensile ductility. Likewise, improvements of up to 98 MPa (57%) in fatigue strength were recorded. Mechanical gains were a result of densification and residual oxide disruption, as well as the enhanced dispersion of the AlN phase.

Spark plasma sintering (SPS) is a fairly novel powder metallurgy (PM)-based process. Compared with more traditional PM processes, SPS technology provides greater sintering efficiency for the Ti-48Al alloy, due to its fast heating and cooling rates, combined with an applied pressure and electric field during the process. In this study, three fundamental processing parameters (i.e. sintering temperature, time and particle size) are investigated, and their effects on densification, hardness and phase transformations are studied. Three grain morphologies were found in the microstructures, present in different ratios in the samples, depending on the sintering parameters. A model is proposed to explain the (α2) grain-phase growth and the transformation of two types (fine and coarse) of lamellar structural development. The pore configurations (i.e. size and quantity) are examined, and their interactions with the phases, which suggest the phase-formation sequence and sintering state, are also discussed.

Ubiquitin C-terminal hydrolase L1 (UCH-L1) is an extremely abundant protein in the brain where, remarkably, it is estimated to make up 1–5% of total neuronal protein. Although it comprises only 223 amino acids it has one of the most complicated 3D knotted structures yet discovered. Beyond its expression in neurons UCH-L1 has only very limited expression in other healthy tissues but it is highly expressed in several forms of cancer. Although UCH-L1 is classed as a deubiquitinating enzyme (DUB) the direct functions of UCH-L1 remain enigmatic and a wide array of alternative functions has been proposed. UCH-L1 is not essential for neuronal development but it is absolutely required for the maintenance of axonal integrity and UCH-L1 dysfunction is implicated in neurodegenerative disease. Here we review the properties of UCH-L1, and how understanding its complex structure can provide new insights into its roles in neuronal function and pathology.

The timing of landscape change, post-settlement alluvium (PSA) deposition and gully erosion in the southeastern Australian Tablelands remains at the centre of a long-standing discussion over the geomorphological effects of European land-use compared with Aboriginal land-use and climate change. Few quantitative studies date the onset of gully erosion and subsequent PSA deposition in the Tablelands and those that do determine the timing of landscape change for individual catchments rather than across the region. In this study, we present optically stimulated luminescence (OSL) burial ages of swampy meadow (SM) sediment and PSA from six sites spread throughout the Goulburn Plains to place better regional constraints on the timing of landscape change. PSA burial ages at each of our sample sites range between 213 and 81 years before AD 2013, the year during which all samples were collected and measured – corresponding to AD 1800–1932. All measured PSA burial ages post-date European arrival to Australia and are therefore consistent with the generic name and implied age assigned to these sediments before quantitative age estimates were available for them. We suggest, however, that the term ‘post-European settlement alluvium’ may be more appropriate in the Australian context as Aboriginal Australians were living in the Tablelands prior to European arrival. Associations between the occurrence of gully incision and PSA deposition throughout the Tablelands and climatic factors are tenuous, and we suggest that European land-use practices in the region dominate landscape evolution, which had been driven by climatic factors throughout the Holocene.

The corrosion behaviour of the commercial aluminium powder metallurgy alloy ‘Alumix 123’ after undergone ‘sizing’, a standard cold forming operation, has been studied in naturally aerated 3.5 wt-% NaCl solution through open circuit potential (OCP), cathodic potentiodynamic polarisation, cyclic potentiodynamic polarisation and potentiostatic polarisation experiments, and the subsequent corrosion morphology was characterised by scanning electron microscopy and energy dispersive X-ray spectroscopy. The results were compared to those obtained for Alumix 123 in the ‘as-sintered’ condition and to a compositionally similar wrought alloy, AA2014-T6. The sizing operation significantly affected the OCP, corrosion control, cathodic process, corrosion rate and corrosion morphology of Alumix 123. These changes are attributed to the reduction in open surface porosity brought about by the sizing operation. It appears that with a single secondary operation, sizing, the corrosion resistance of Alumix 123 is significantly ...

Human land-use changes leading to widespread erosion and gully incision have been well studied, but the effects that erosion and sediment mixing, which accompany the deposition of post-(European) settlement alluvium (PSA), have in valley bottoms and wetlands receive considerably less attention. PSA overlying pre-disturbance swampy meadow (SM) wetland sediments is commonly exposed along incised stream channel gully walls throughout the south-eastern Australian Tablelands, providing an ideal setting in which to assess and understand better how PSA deposition affects valley bottoms and the wetland environments that often occupy them. Portable optically stimulated luminescence (pOSL) reader data were measured on bulk sediment samples from SM-PSA stratigraphies at 16 locations throughout the south-eastern Australian Tablelands to assess the effects of erosion and sediment mixing at the SM-PSA boundary. Trends of pOSL data with depth at each profile were used in conjunction with visual profile descriptions to identify the stratigraphic boundary between SM and PSA sediment and to infer the degree of valley bottom erosion and sediment mixing during PSA deposition. At most sites, SM sediments experienced minimal, if any, disturbance during PSA deposition, and we refer to these as non-eroded sites. Many sites, however, experienced a significant degree of erosion and sediment mixing – eroded sites – often corresponding to visually diffuse sedimentary boundaries between the two stratigraphic units. Our findings demonstrate that SM landscapes in the Tablelands can be preserved with minimal disturbance under PSA at non-eroded sites and are preserved beneath a mixing zone at all eroded sites. Copyright © 2016 John Wiley & Sons, Ltd.

The objective of this research was to develop a powder metallurgy (PM) counterpart to the wrought aluminum alloy 2618 utilizing press-and-sinter technology. Each starting blend was prepared from a strategic combination of prealloyed aluminum coupled with elemental and master alloy additions and was processed through uni-axial die compaction coupled with controlled atmosphere sintering. All of the PM alloys responded well to sintering with near full theoretical density realized. The most desirable PM product contained minor additions of tin and silicon. Whereas tin imparted enhanced densification, silicon promoted appreciable gains in hardness and tensile properties. It was also determined that the beneficial effects of silicon persevered after prolonged thermal exposure at 260 °C provided that a nominal concentration of 0.2 wt% was maintained. The final press-and-sinter PM product offered mechanical properties and thermal stability that were comparable to the wrought target.

The objective of this research was to commence work on the spark plasma sintering (SPS) of Al–Sc alloys in an effort to develop fundamental data in this area. In this precursory study, a series of binary systems containing 0.1 to 0.4 wt% Sc were processed in laboratory and industrial-scale equipment. Data revealed that all powders were responsive to SPS in both scenarios and that sintering temperature was a variable of critical importance. Hardness of as-sintered products scaled directly with Sc concentration but varied inversely with SPS temperature owing to in-situ aging of the raw powders. Hardness losses could be recovered through a post-SPS heat treatment into the T6 condition. Industrially processed slugs of Al-0.4Sc-T6 exhibited full densification and offered the highest hardness (786+/−8 MPa). This was accompanied by a nominal tensile yield strength of 197 MPa, UTS of 226 MPa and tensile ductility of 11%.

Despite, or perhaps because of, the uncertainty of its origins, the strand of Islamic spirituality known as Sufism has increasingly attracted the attention of scholars and popular culture alike. Th...

During sintering of blended powders by spark plasma sintering (SPS), short sintering times are opposed by the requirement of sufficient diffusion times to obtain chemical homogenization. In this study, commercially blended Al-alloy powder Alumix 431D was sintered by SPS at 425 °C for various sintering times. Microstructure analysis and mechanical properties of the consolidated components in the T1 and T6 states were evaluated. Densities between 97.5 and 99.7%TD were obtained across all hold times. After sintering for 60 min, microhardnesses of 91±8 and 143±6 HV were attained in the T1 and T6 conditions, respectively. The T1 samples had a flexural strength of 659±37 MPa and a flexural strain of 5.7±0.3%, compared to 552±43 MPa and 3.8±0.2% in the T6 temper. The mechanical properties of the T6 components were lower than those found in the literature. Extensive solution heat treatments of 2 and 4 h were performed prior to aging.

Aluminum-based metal matrix composite (MMC) materials containing SiC, AlN, Si3N4 or BN were processed by spark plasma sintering (SPS). Ceramic powder type, size and content were investigated to determine their effect on sinter quality. SiC, AlN and Si3N4 proved to be amenable to this style of processing whereas all systems containing BN were not. Full densification of MMCs that incorporated finer ceramic particles was problematic due to the presence of ceramic clusters and the extent to which aluminum could be forced into these regions. MMCs that incorporated coarser ceramic particles were more easily densified, but their hardness benefits were inferior. Three point bend tests proved to be an effective tool in determining the relative sinter quality of MMC systems. SiC outperformed AlN MMC samples in bend tests. Excellent ductility and bend strength was developed at low temperatures, while equivalent AlN-bearing materials required significantly higher temperatures to achieve comparable properties.

Portable optically stimulated luminescence (OSL) readers are increasingly being used in geomorphological and archaeological investigations, but information regarding data reproducibility and the reliability of interpretations based on portable OSL reader data has not yet been presented to the wider geomorphological community. This Letter addresses these two issues by returning to Grabben Gullen Creek in the southeastern Australian Tablelands where we remeasure a sediment profile that was first measured by other researchers 3 years earlier. We also compare portable OSL reader data measured on sediment interpreted to have been deposited in swampy meadow wetlands and flood alluvium settings with data measured on known swampy meadow and flood deposits. Our data show that portable OSL reader data are reproducible. Moreover, we confirm the earlier interpretation that stratigraphies commonly exposed in southeastern Australian Tablelands valley bottoms reflect pre-European swampy meadow wetlands and flood alluvium. Copyright © 2015 John Wiley & Sons, Ltd.

This review discusses Jung and Intuition: On the Centrality and Variety of Forms of Intuition in Jung and Post-Jungians, a study of the notion of intuition in the work of Jung. It concludes that the chief of many insights brought by Nathalie Pilard’s work is an appreciation of the importance in Jung’s thought of the notion of empathy.

Although this volume appears in a series entitled Historical Dictionaries, it is (as its two authors, Graham Harvey and Robert J. Wallis, point out) difficult to provide a strict chronology or clea...