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Objective: Our goals were to validate stone comminution with an investigational burst wave lithotripsy (BWL) system in patient-relevant conditions and to evaluate the use of ultrasonic propulsion to move a stone or fragments to aid in observing the treatment endpoint. Materials and Methods: The Propulse-1 system, used in clinical trials of ultrasonic propulsion and upgraded for BWL trials, was used to fragment 46 human stones (5–7 mm) in either a 15-mm or 4-mm diameter calix phantom in water at either 50% or 75% dissolved oxygen level. Stones were paired by size and composition, and exposed to 20-cycle, 390-kHz bursts at 6-MPa peak negative pressure (PNP) and 13-Hz pulse repetition frequency (PRF) or 7-MPa PNP and 6.5-Hz PRF. Stones were exposed in 5-minute increments and sieved, with fragments >2 mm weighed and returned for additional treatment. Effectiveness for pairs of conditions was compared statistically within a framework of survival data analysis for interval censored data. Three reviewers blinded to the experimental conditions scored ultrasound imaging videos for degree of fragmentation based on stone response to ultrasonic propulsion. Results: Overall, 89% (41/46) and 70% (32/46) of human stones were fully comminuted within 30 and 10 minutes, respectively. Fragments remained after 30 minutes in 4% (1/28) of calcium oxalate monohydrate stones and 40% (4/10) of brushite stones. There were no statistically significant differences in comminution time between the two output settings (p = 0.44), the two dissolved oxygen levels (p = 0.65), or the two calyx diameters (p = 0.58). Inter-rater correlation on endpoint detection was substantial (Fleiss' kappa = 0.638, p

This study provides two mathematical tools to best estimate the gravity direction when using a pair of non-orthogonal inclinometers whose measurements are affected by zero-mean Gaussian errors. These tools consist of: (1) the analytical derivation of the gravity direction expectation and its covariance matrix, and (2) a continuous description of the geoid model correction as a linear combination of a set of orthogonal surfaces. The accuracy of the statistical quantities is validated by extensive Monte Carlo tests and the application in an Extended Kalman Filter (EKF) has been included. The continuous geoid description is needed as the geoid represents the true gravity direction. These tools can be implemented in any problem requiring high-precision estimates of the local gravity direction.

INTRODUCTION AND OBJECTIVE:Our goals were to validate stone comminution with an investigative clinical burst wave lithotripsy (BWL) system and to evaluate the use of ultrasonic propulsion to move t...

INTRODUCTION AND OBJECTIVE:Artificial stone models are used in lithotripsy research. While the value of models is their availability and reproducibility in shape and characteristics, a challenge re...

Anthony Gardner traces the discomfiting symmetries between documenta 14 and austerity-ridden Athens.

The question this article asks is how exhibition histories of contemporary art shift when seen not from the perpetually insistent demands of the north, but from the viewpoints and aspirations of the South. What might a Southern perspective of biennials look like? These largely occluded histories do not quite fit the habitual framings of biennials as beginning with a first wave at the close of the nineteenth century and segueing neatly into the neo-imperial tidal force of the 1990s and 2000s. They instead coincide with what we consider to be a second wave of biennialization that developed from the mid-1950s into the 1980s, and which insisted upon a self-conscious, critical regionalism as the means for realigning cultural networks across geopolitical divides. Biennials of the South had grasped their place in the postwar arc of neo-colonial globalism. But, even more importantly, they then converted that place into the resistant image of cultural, art historical and international reconstruction.

Conventional analyses of the Cold War rely on a static binary division between the US and the USSR. This article, focusing on art and film production in Italy between 1946 and 1963, reveals a more complex and dynamic interaction between cultures beyond this binary. In Cold War Italy, important cultural exchanges and networks emerged across political, national and intellectual boundaries. By placing an Italian case study at the centre of the analysis, we propose more generally that Cold War art and cinema should be read as culturally inventive, politically charged and globally networked in unexpected ways. These networks provide us with new directions for understanding Cold War cultures and how they presage present-day globalisation.

Why, since the late 1980s, have a number of European artists critiqued democracy as the political, critical and aesthetic frame within which to identify their work? How have they done this? And what aesthetic and political discourses have artists proposed in lieu of the democracy they critique? Using these questions as its guide, this article examines the work of Soviet artist Ilya Kabakov, and its influence on artists such as Christoph Buchel and Gianni Motti, to present an alternative to the aesthetics of democratization that have dominated much contemporary art theory in Western Europe, such as the relational aesthetics of Nicolas Bourriaud and the contextual aesthetics of Paul Ardenne. Rather than absorb and reiterate existing discourses of democracy—discourses made especially problematic after 9/11 and during the wars in Iraq and Afghanistan—this article proposes that post-communist rethinkings of democracy can instead provide different ways for imagining art's political potential, or even the aesthe...

Politics of memory are absolutely crucial to rethinking the conditions of the contemporary. Returning to specific histories of the ‘avant‐garde’ remains problematic, however, for it still leaves open the questions of which histories or even whose histories serve as the font for ‘legitimate’ critique, and thus whose ‘avant‐garde’? Are there other politics of memory to consider beyond these ubiquitous conceptual frames? This article follows the lead of a number of artists who have remobilised different cultural histories as a font for contemporary collective action. These are histories of dissident aesthetics and potentials that do not belong to the ‘avant‐garde’, but instead stem from Indigenous rebellion in colonial Australia (in Tom Nicholson’s marches) and critiques developed in late Communist Europe (Lia Perjovschi’s workshops). Drawn together, these retracings can advance our knowledge of still‐marginalised histories, as was Third Text’s original brief back in the 1980s, while opening up pros...

The focus of this essay is the indisputably important 1979 Biennale of Sydney, which launched Sydney's biennial as an international event seeking out adventurous art from Western Europe and the USA. We will argue that it sought both to present an image of the world of contemporary art and also, more critically, to embody a key strand of the globalising art world's emerging contemporaneity.By the end of the 1970s, the arrival of relatively affordable international flights had pushed Australian artists, along with their peers from other 'margins' of contemporary art, into closer contact with North Atlantic art centres. The result was the beginning of a Balkanisation of art worlds beyond New York and Western Europe: within each art centre, a division into two overlapping art worlds, a provincial ghetto represented by one set of commercial art galleries or an international art world enclave represented by another, usually smaller and more exclusive, number of galleries and, increasingly, some artist-run spaces.1This was as true in Tokyo as it was in Sydney or Melbourne. The two art worlds overlapped but the latter world-that which saw itself as international and part of a nascent, globalised art world-did not at that time or later necessarily renew itself from the former's talent-pool of the best and brightest, and then only reluctantly or in such a way as to reinforce North Atlantic primacy over the image of what was contemporary art. Many scholars' recent work, particularly that of John Clark, has shown that this remained true even of the huge Asian biennials that flourished from the 1990s onwards though, increasingly, many younger artists moved easily from international artist residency to residency and from biennial to biennial.2Founding the Sydney BiennaleBoth the Sao Paulo and Sydney Biennales were founded by immigrants from post-War Europe-in Sao Paulo, Francisco Matarazzo Sobrinho; in Sydney, Franco Belgiorno-Nettis. Their motivations were similar, and they had been affected by their own experiences of post-World War Π diaspora. They were European migrants who established themselves as important industrialists, proudly participating in their chosen city's civic and national desires for international recognition as nascent global cities and as nodes of business and capital in their respective regions in the Southern Hemisphere. Needless to say, civic and national aspirations were never identical nor necessarily in harmony, nor was the balance between the two always equal. Whereas the Federal Government's new Australia Council for the Arts wished primarily to support art-making nationwide and far less to project Australian art internationally. Its aim was to maximise direct support to Australian artists in the form of grants. Belgiorno-Nettis, on the other hand, wanted to replicate and import the cultural institutions of his homeland to his beloved Sydney, and in particular the venerable institution of the Biennale of Venice:My love affair with Venice, where I have been a frequent visitor for years, is the source of inspiration for the Biennale. How do you break the isolation of Australia, which I felt strongly myself in the early 50s? How do you inject that flavor of international extravaganza, originality and explosive vision that you see at gatherings in Venice, in the Giardini, in the Corderia, in the Arsenale, with their centuries of tradition?3Other biennial models than that of Venice were already available, principally the idea of a biennial of the South, current from 1955 onwards, that we have written about elsewhere.4 These ideas might just as easily have been adopted, but there is no evidence that they were discussed and Belgiorno-Nettis's civic-minded boosterism, nostalgia and philanthropy prevailed. He invented, underpinned and financially supported the new biennial with the organisational and curatorial resources provided by his family conglomerate, the powerful Transfield Corporation, which built bridges, railways and major infrastructure projects. …

How are we to understand the nexus of art, televisual imagery and the politics of democracy in the early twenty-first century, at a time when “democracy” has supposedly reached an apotheosis in global politics, and documentary imagery on television screens has returned as a core trope within contemporary art? And what role is art sometimes made to play in promoting certain political discourses within problematic contexts? In 2004, these questions emerged as central to the inauguration of the National Museum of Contemporary Art in Bucharest, Romania – a museum whose location and date of inauguration were dictated by Romania’s then-Social Democratic government, in the run-up to the country’s important 2004 elections and its accession to the European Union. Invited to participate in the museum’s inauguration, two Swiss-based artists, Christoph Buchel and Gianni Motti, devised an untitled installation that took “democracy” as its subject. A close examination of this work reveals a subtle critique of television’s place, and installation’s potential, within histories of postcommunist art and politics, as well as of the various presumptions made – of the artists, of television, and of encounters between “East” and “West” – in the name of “democracy”.

Institute of Occupational Medicine dual-fraction samplers equipped with porous polyurethane foam inserts have been introduced as a cheaper alternative to cyclone pre-selectors for measuring respirable dust. Initial data from a variety of industries suggested that the dual-fraction sampler yielded similar results as personal cyclones and that the respirable selection of the foam was not adversely affected by particle loading. We conducted a similar study, but specifically in the brick industry to assess the validity of this dual-fraction sampler as an alternative to personal cyclones in this industry. A total of 72 side-by-side samples using Higgins-Dewell cyclones and dual-fraction samplers were taken in seven UK factories manufacturing a variety of bricks. A priori measurements were assigned to any of the three groups based on the dominant source of the particulates in the exposure matrix (clay, sand or mixed) at the location in the factories where the measurements were taken. After log transformation, Higgins-Dewell cyclone-measured concentrations were on average 1.9 times higher than the concentrations measured by the dual-fraction samplers, with a Pearson correlation of 0.78 (95% confidence interval 0.66-0.85). Stratified analysis by main source of exposure suggested that the correlation was best for silica dust-based exposures r(p) = 0.88 (0.63-0.96), but decreased with the relative importance of clay particulates in the exposure matrix to r(p) = 0.82 (0.59-0.93) in the 'mixed-source' group and r(p) = 0.74 (0.55-0.85) in the 'clay particulates' group. Similarly, performance of the dual-fraction sampler relative to the cyclone sampler was negatively associated with increased relative importance of clay particulates in the exposure matrix and ranged from similar measured concentration beta = 0.96 (0.54-1.39) for silica to 50% under sampling beta = 0.50 (0.33-0.67) for clay particulates. These results suggested that the overall performance of the dual-fraction sampler in the brick industry depends on the relative importance of clay particulates in the exposure matrix. As such, results from occupational hygiene compliance surveys close to the occupational exposure limit can lead to erroneous decisions on compliance.

As originally conceived by President Ronald Reagan, the Strategic Defense Initiative was potentially more disruptive of transatlantic relations than the Sentinel antiballistic missile system of 1967 or the Safeguard system of 1969. While Sentinel and Safeguard were short-term programs with specific and limited objectives, SDI was a vague, longterm program aimed at substituting an ambitious area defense of the United States for the doctrine of Mutual Assured Destruction, which many Western Europeans believe is responsible for 40 years of peace in Europe. Unlike Sentinel and Safeguard, SDI posed a serious threat to a major arms control agreement. Many Western European leaders consider the 1972 ABM Treaty to be a crucial component of Western security and an important symbol of superpower cooperation. Given current budgetary constraints and SDI's more modest objectives under the Bush administration, the ABM Treaty is no longer perceived in Western Europe to be in jeopardy. Moreover, SDI no longer appears to be an insurmountable obstacle to the successful completion of the Strategic Arms Reduction Talks.