Electron and ion stagnation at the collision front between two laser produced plasmas

We report results from a combined optical interferometric and spectrally resolved imaging study on colliding laser produced aluminium plasmas. A Nomarski interferometer was used to probe the spatio-temporal distribution of electron densities at the collision front. Analysis of the resulting interferograms reveals the formation and evolution of a localized electron density feature with a well-defined profile reminiscent of a stagnation layer. Electron stagnation begins at a time delay of 10 ns after the peak of the plasma generating laser pulse. The peak electron density was found to exceed 10^19 cm^−3 and the layer remained well defined up to a time delay of ca 100 ns. Temporally and spectrally resolved optical imaging was also undertaken, to compare the Al^+ ion distribution with that of the 2D electron density profile. This revealed nascent stagnation of singly charged ions at a delay time of 20 ns. We attribute these results to the effects of space charge separation in the seed plasma plumes

An agenda for creative practice in the new mobilities paradigm

Creative practices have made a standing contribution to mobilities research. We write this article as a collective of 25 scholars and practitioners to make a provocation: to further position creative mobilities research as a fundamental contribution and component in this field. The article explores how creative forms of research—whether in the form of artworks, exhibitions, performances, collaborations, and more—has been a foundational part of shaping the new mobilities paradigm, and continues to influence its methodological, epistemological, and ontological concerns. We tour through the interwoven history of art and mobilities research, outlining five central contributions that creativity brings. Through short vignettes of each author’s creative practice, we discuss how creativity has been key to the evolution and emergence of how mobilities research has expanded to global audiences of scholars, practitioners, and communities. The article concludes by highlighting the potency of the arts for lively and transdisciplinary pathways for future mobilities research in the uncertainties that lay ahead

Rumours, sects and rallies : the ethnic politics of recent Hmong Millenarian movements in Vietnam’s highlands

Contrary to modernist assumptions, millenarianism has not died out but continues to influence the politics of many marginalised groups in upland Southeast Asia, including the Hmong. This article summarises and analyses post-World War II Hmong millenarian activity in Vietnam, focusing on three case studies from the 1980s onwards, within the political backdrop of ongoing government suspicions of ethnic separatism and foreign interference. Far from being isolated or peripheral, Hmong millenarian rumours and movements interact with overseas diasporas, human rights agencies and international religious networks to influence state responses, sometimes in unexpected ways

Pesticides and Parkinson’s Disease—Is There a Link?

Parkinson’s disease (PD) is an idiopathic disease of the nervous system characterized by progressive tremor, bradykinesia, rigidity, and postural instability. It has been postulated that exogenous toxicants, including pesticides, might be involved in the etiology of PD. In this article we present a comprehensive review of the published epidemiologic and toxicologic literature and critically evaluate whether a relationship exists between pesticide exposure and PD. From the epidemiologic literature, there does appear to be a relatively consistent relationship between pesticide exposure and PD. This relationship appears strongest for exposure to herbicides and insecticides, and after long durations of exposure. Toxicologic data suggest that paraquat and rotenone may have neurotoxic actions that potentially play a role in the development of PD, with limited data for other pesticides. However, both the epidemiology and toxicology studies were limited by methodologic weaknesses. Particular issues of current and future interest include multiple exposures (both pesticides and other exogenous toxicants), developmental exposures, and gene–environment interactions. At present, the weight of evidence is sufficient to conclude that a generic association between pesticide exposure and PD exists but is insufficient for concluding that this is a causal relationship or that such a relationship exists for any particular pesticide compound or combined pesticide and other exogenous toxicant exposure

'Gain with no pain’: anabolic-androgenic steroids trafficking in the UK

Anabolic-androgenic steroids are performance and image enhancing drugs (PIED) that can improve endurance and athletic performance, reduce body fat and stimulate muscle growth. The use of steroids has been studied extensively in the medical and psychological literature, as well as in the sociology of sport, health and masculinity. From the late 2000s, the worldwide trade in steroids increased significantly. However, trafficking in steroids remains a largely under-researched criminological phenomenon with a few notable exceptions. Currently in the UK there are only small and fragmented pieces of information available relating to steroids trafficking in autobiographical accounts of professional criminals. Drawing on original empirical data, the purpose of this article is to provide an account of the social organization of the steroids trafficking business in the UK. The trade in steroids is decentralized, highly flexible with no hierarchies, and open to anyone willing to either order the merchandise online or travel to producing countries and obtain steroids in bulk from legitimate manufacturers. The patterns of trafficking of this specific type of substance are patently conditioned by its embeddedness in the gym/bodybuilding scene and this greatly affects relations between actors in the business. In the steroids market, one typically encounters a multitude of individuals likely to drift between legality and illegality, online and offline, use and supply

第16巻 第2号 表紙

Background The effectiveness of using point-of-care (POC) urine culture in primary care on appropriate antibiotic use is unknown. Aim To assess whether use of the Flexicult™ SSI-Urinary Kit, which quantifies bacterial growth and determines antibiotic susceptibility at the point of care, achieves antibiotic use that is more often concordant with laboratory culture results, when compared with standard care. Design and setting Individually randomised trial of females with uncomplicated urinary tract infection (UTI) in primary care research networks (PCRNs) in England, the Netherlands, Spain, and Wales. Method Multilevel regression compared outcomes between the two groups while controlling for clustering. Results In total, 329 participants were randomised to POC testing (POCT) and 325 to standard care, and 324 and 319 analysed. Fewer females randomised to the POCT arm than those who received standard care were prescribed antibiotics at the initial consultation (267/324 [82.4%] versus 282/319 [88.4%], odds ratio [OR] 0.56, 95% confidence interval [CI] = 0.35 to 0.88). Clinicians indicated the POCT result changed their management for 190/301 (63.1%). Despite this, there was no statistically significant difference between study arms in antibiotic use that was concordant with laboratory culture results (primary outcome) at day 3 (39.3% POCT versus 44.1% standard care, OR 0.84, 95% CI = 0.58 to 1.20), and there was no evidence of any differences in recovery, patient enablement, UTI recurrences, re-consultation, antibiotic resistance, and hospitalisations at follow-up. POCT culture was not cost-effective. Conclusion Point-of-care urine culture was not effective when used mainly to adjust immediate antibiotic prescriptions. Further research should evaluate use of the test to guide initiation of ‘delayed antibiotics’

Differential profiles of <i>c-fos</i> expression within primary cultures of mouse cerebellar granule cells stimulated with the excitatory amino acid L-glutamate: correlation with excitotoxic outcome and derivation of a predictive index.

Exposure of mouse cerebellar granule cells to L-glutamate (Glu) at low non-excitotoxic concentrations results in a transient expression of the c-fos proto-oncogene. Higher excitotoxic concentrations of Glu result in a change in the temporal profile of c-fos expression to a delayed but sustained response. We have derived a ratio for the steady-stare levels of c-fos mRNA after 30 min and 240 min of exposure to Glu, which suggests that a 240 min/30 min ratio of greater than 1 correlates with excitotoxicity (as measured by elevated LDH release), whereas a ratio of less than 1 correlates with a non-excitotoxic outcome. (C) 1997 Elsevier Science Ltd.</p